Valley Grasshopper (Oedaleonotus enigma): COSEWIC assessment and status report 2024

Official title: COSEWIC assessment and status report on the Valley Grasshopper (Oedaleonotus enigma) in Canada

Committee on the status of Endangered Wildlife in Canada (COSEWIC)

Endangered 2024

COSEWIC assessment summary

Assessment summary – November 2024

Common name: Valley Grasshopper

Scientific name: Oedaleonotus enigma

Status: Endangered

Reason for designation: This grasshopper is known from one very small area near Osoyoos, British Columbia, where it occurs in some of the hottest and driest grassland habitat in Canada. The species is at risk from potential housing developments and there is a continuing decline in the quality of its habitat due to recreational activities (unregulated camping and all-terrain vehicle use) and garbage accumulation.

Occurrence: British Columbia

Status history: Designated Endangered in November 2024.

COSEWIC executive summary

Valley Grasshopper

Oedaleonotus enigma

Wildlife species description and significance

Valley Grasshopper is identified at the adult life stage by three distinguishing features: a narrow, conspicuously white to cream-coloured band or collar on the anterior edge of the pronotum; the hindleg femur with distinct dark brown chevrons separated by tan lines; and blue hindleg tibia. Adults show wing dimorphism: the hard leathery front wings can be short (individuals cannot fly) or long (individuals can fly). The proportion of these wing forms varies between years.

Valley Grasshopper is of interest to entomologists due to its rarity and close association with the Antelope-brush and sagebrush ecological communities of the south Okanagan.

Aboriginal (Indigenous) knowledge

All species are significant, interconnected, and interrelated. There is no species-specific Aboriginal traditional knowledge in this status report.

Distribution

Valley Grasshopper ranges in western North America from southern British Columbia (B.C.), south through eastern Washington, Oregon, Idaho, Montana and Nevada, and southwest to southern California and northern Mexico, with a potentially disjunct subpopulation in Utah. In Canada, Valley Grasshopper has a restricted range and occurs in extreme southern B.C. There is one known resident subpopulation on untitled provincial land (Osoyoos West Bench) adjacent to the international border.

Valley Grasshopper was first recorded in Canada from pitfall traps in 2010, and the most recent records are from hand collections in 2023. Pitfall trapping (2013, 2023), grasshopper-specific wandering transect surveys using hand collection (2021, 2023), and incidental collections throughout the species’ potential range and habitat in Canada have not revealed additional subpopulations. There is some partially surveyed habitat adjacent to Osoyoos West Bench in the South Okanagan Grasslands Protected Area and the Sage and Sparrow Conservation Area, where there are likely additional subpopulations.

Habitat

Valley Grasshopper inhabits the lower elevation (<700 m) areas of the Bunchgrass (BG) Okanagan Very Dry Hot (BGxh1) biogeoclimatic variant, which includes some of the hottest and driest habitats in the country. The dominant shrubs are Big Sagebrush and Antelope-brush, with some Common Rabbit-bush. The dominant forbs and grasses are Bluebunch Wheatgrass, Prickly Pear Cactus, Needle-and-thread Grass, June Grass, Sandberg’s Bluegrass, and Low Pussytoes.

Biology

Valley Grasshopper has an annual life cycle. The species overwinters as an egg (Aug/Sept-April) and hatches as a nymph in the early spring (April/May). Nymphs grow by gradual metamorphosis through the six nymphal instars from May through August before becoming adults in August. Adults are active from early August through late September, and mating and oviposition occurs during this time.

Valley Grasshopper nymphs hatch from overwintering eggs earlier than most other grasshopper species. They grow slowly (likely due to cooler spring temperatures) and have more nymphal instars than most other grasshoppers (grasshoppers typically have five instars). Warmer temperatures yield more short-winged adults, and cooler temperatures yield more long-winged adults. The species is a polyphagous herbivore, feeding on forbs, shrubs, and to a lesser extent on grasses.

Population sizes and trends

There is no information on the Canadian population size or trends. Fewer than 10 specimens have been collected and deposited as museum vouchers. Surveys from 2010 to present have focused on recording new subpopulations, natural history, and habitat information; these methods do not allow for population estimates.

Threats

The most serious and plausible threat to Valley Grasshopper is the potential for Osoyoos West Bench to be lost to urban development within the next 10 years. Other threats include drought resulting from climate change, ongoing cumulative loss, as well as degradation and fragmentation of this property and adjacent habitats from intensive all-terrain vehicle use, long-term camping, and garbage accumulation. Threats to the private lands adjacent to and within 1 km of Osoyoos West Bench include habitat loss to agricultural land conversion (for example, the conversion of natural habitat) or intensification (for example, conversion of tree fruit crops to vineyards).

Protection, status, and recovery activities

Valley Grasshopper is not listed or protected under provincial or federal legislation. It is known from the Osoyoos West Bench, a large parcel of untitled provincial land. The entire Osoyoos West Bench is within a Notation of Interest and Section 16 Map Reserve, which is a land tenure (under the B.C. Land Act) that serves to inform government and other tenure holders (or would-be tenure holders or developers) about the potential interest in a given parcel for environmental and conservation purposes. However, this does not protect the land from being sold, leased, or developed. The Osoyoos West Bench is also within the working boundaries of the South Okanagan National Park Reserve, but until the park is formally established, this offers no formal protection. NatureServe lists the species’ global status as G5 (Secure), and the Canadian national and B.C. status ranks are N1 and S1, respectively (both Critically Imperilled). It is not part of any species-specific conservation activities.

Technical summary

Oedaleonotus enigma

Valley Grasshopper

Criquet énigmatique

Indigenous names: None known

Range of occurrence in Canada: British Columbia

Demographic information

Generation time (usually average age of parents in the population)

1 year

Eggs hatch in early spring and nymphs grow by incomplete metamorphosis over the summer months; mating and egg laying occur in Aug-Sept; adults die late fall.

Is there an [observed, estimated, inferred, or projected] continuing decline in number of mature individuals?

Unknown

Insufficient data to calculate.

[Observed, estimated, or projected] percent of continuing decline in total number of mature individuals within 3 years [or 1 generation; whichever is longer up to a maximum of 100 years]

Unknown

Unknown

Observed, estimated, or projected] percent of continuing decline in total number of mature individuals within 5 years [or 2 generations; whichever is longer up to a maximum of 100 years]

Unknown

Unknown

[Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over the last 10 years [or 3 generations; whichever is longer]

Unknown

Unknown

[Projected, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over the next [10 years, or 3 generations, up to a maximum of 100 years]

Unknown

Unknown

[Observed, estimated, inferred, projected, or suspected] percent [reduction or increase] in total number of mature individuals over any period of 10 years [or 3 generations; whichever is longer, up to a maximum of 100 years], including both the past and future (up to a maximum of 100 years in future)

Unknown

Unknown

Are the causes of the decline clearly reversible?

No

Potential habitat loss to urban development in the next 10 years; decline in habitat quality from ongoing recreational use, long-term camping, garbage accumulation, and other threats.

Are the causes of the decline clearly understood?

Yes

Potential habitat loss to urban development in the next 10 years; decline in habitat quality from ongoing recreational use, long-term camping, garbage accumulation, and other threats.

Are the causes of the decline clearly ceased?

No

Potential habitat loss to urban development in the next 10 years; decline in habitat quality from ongoing recreational use, long-term camping, garbage accumulation, and other threats.

Are there extreme fluctuations in number of mature individuals

Unknown

Not observed in Canada or at the periphery of its global range but data are scant; data from other areas in its North American range suggest the species may experience extreme fluctuations.

Extent and occupancy information

Estimated extent of occurrence (EOO)

4 to 9.3 km²

The minimum EOO, as measured with a convex polygon around known records is <1 km²; therefore, the value of the minimum IAO is used. The maximum EOO is an estimate based on a polygon around known occurrences and potential habitat in nearby protected areas.

Index of area of occupancy (IAO), reported as 2x2 km grid value

4 to 20 km²

Calculated based on known occurrences from 2010 to 2023 and potential habitat in nearby protected areas.

Is the population “severely fragmented”, that is, is > 50% of individuals or > 50% of the total area “occupied” (as a proxy for number of individuals) in habitat patches that are both (a) smaller than required to support a viable subpopulation, and (b) separated from other habitat patches by a distance larger than the species can be expected to disperse?

1. No
2. Unknown

1. The minimum patch size to sustain a viable subpopulation is unknown. However, based on the presence of the grasshopper at the Osoyoos West Bench since 2010, there is likely sufficient habitat to sustain a subpopulation
2. The species is only known from one subpopulation; dispersal distance is unknown although individuals may disperse up to 1 km through suitable habitat

Number of “locations” (use plausible range to reflect uncertainty if appropriate)

1 to 5

Based on differing threats within the habitat patches where the grasshopper is known to occur.

Is there an [observed, inferred, or projected] continuing decline in extent of occurrence?

Unknown

Insufficient data to calculate.

Is there an [observed, inferred, or projected] continuing decline in area of occupancy?

Unknown

Insufficient data to calculate.

Is there an [observed, inferred, or projected] continuing decline in number of subpopulations?

No

Only a single subpopulation is known.

Is there an [observed, inferred, or projected] continuing decline in number of “locations”?

Unknown

Insufficient data to calculate.

Is there an [observed, inferred, or projected] continuing decline in [area, extent and/or quality] of habitat?

Yes

Observed and inferred decline in area, extent and quality of habitat based on potential land development, recreational use, garbage accumulation, and potentially agricultural development.

Are there extreme fluctuations in number of subpopulations?

No

Only a single subpopulation is known.

Are there extreme fluctuations in number of “locations”?

No

Unlikely based on lack of historical and recent records from elsewhere in its potential habitat in Canada.

Are there extreme fluctuations in extent of occurrence?

No

Unlikely based on lack of historical and recent records from elsewhere in its potential habitat in Canada.

Are there extreme fluctuations in index of area of occupancy?

No

Unlikely based on lack of historical and recent records from elsewhere in its potential habitat in Canada.

Number of mature individuals (by subpopulation)

Subpopulation 1: Osoyoos West Bench

Unknown

No data available. From 2010 to 2023, nine specimens/ observations have been recorded.

Total

Unknown

No data available. From 2010 to 2023, nine specimens/observations have been recorded.

Quantitative analysis

Is the probability of extinction in the wild at least 20% within 20 years [or 5 generations], or 10% within 100 years]

Unknown

Analysis not conducted.

Threats

Was a threats calculator completed for this species?

Yes (see Appendix 1)

Overall assigned threat impact: High

Key threats were identified as:

1. Housing and urban areas (IUCN 1.1) – High impact
2. Commercial and industrial areas (IUCN 1.2) – Low impact
3. Recreational activities (IUCN 6.1) – Low impact
4. Garbage and solid waste (IUCN 9.4) – Low impact
5. Droughts (IUCN 11.2) – Low impact
6. Annual and perennial non-timber crops (IUCN 2.1) – Unknown impact
7. Livestock farming and ranching (IUCN 2.3) – Unknown impact
8. Fire and fire suppression (IUCN 7.1) – Unknown impact
9. Other ecosystem modifications (IUCN 7.3) – Unknown impact
10. Invasive non-native/alien species (IUCN 8.1) – Unknown impact
11. Agricultural and forestry effluents (IUCN 9.3) – Unknown impact

What limiting factors are relevant?

• Abundance, morphological form, and development influenced by weather patterns.
• Native predators and parasites.

Rescue effect (from outside Canada)

Status of outside population(s) most likely to provide immigrants to Canada.

Likely stable

Idaho S5 (Secure) (NatureServe 2024). All other jurisdictions where it is known to occur (Washington, Montana, Oregon, Wyoming, Utah, California) have no status rank (SNR). The species is considered a potential agricultural pest in Oregon and Idaho.

Is immigration known or possible?

Possible

Possible immigration based on natural habitat adjacent to Canadian habitat. There are no available records from nearby habitat in Washington State, but search effort there is likely low.

Would immigrants be adapted to survive in Canada?

Yes

Subpopulations in the northern part of the U.S. range occur in similar habitat with similar climate to what is found in Canada.

Is there sufficient habitat for immigrants in Canada?

Yes

Habitat in Canada is developed and patchy, although there are natural areas.

Are conditions deteriorating in Canada?

Yes

Cumulative threats from land development, recreational use, garbage accumulation, and long-term camping.

Are conditions for the source (that is, outside) population deteriorating?

Unknown but likely

Habitat adjacent to Osoyoos West Bench is likely experiencing similar threats (within 100 km of the international border).

Is the Canadian population considered to be a sink?

Unlikely

There is no evidence of the Canadian population being a sink.

Is rescue from outside Canada likely, such that it could lead to a change in status?

Unknown, but likely no

Habitat adjacent to Osoyoos West Bench may be experiencing similar threats. It is unlikely individuals from the U.S. move to this area in large numbers.

Wildlife species with sensitive occurrence data (general caution for consideration)

Could release of certain occurrence data result in increased harm to the Wildlife Species or its habitat?

No

Current Status

COSEWIC status history: Designated Endangered in November 2024

Recommended status and reasons for designation

Recommended status: Endangered

Alpha-numeric codes: B1ab(iii)+2ab(iii)

Reason for change in status: Not applicable

Reasons for designation: This grasshopper is known from one very small area near Osoyoos, British Columbia, where it occurs in some of the hottest and driest grassland habitat in Canada. The species is at risk from potential housing developments and there is a continuing decline in the quality of its habitat due to recreational activities (unregulated camping and all-terrain vehicle use) and garbage accumulation.

Applicability of criteria

A: Decline in total number of mature individuals

Not applicable.

Not applicable. Insufficient data to reliably infer, project, or suspect population trends

B: Small Range and Decline or Fluctuation

Meets Endangered B1ab(iii)+2ab(iii)

Meets Endangered, B1ab(iii)+2ab(iii). EOO (4 to 9.3 km²) and IAO (4 to 20 km²) are below the threshold for Endangered, and the population is (a) known to exist at < or = 5 locations, and (b) experiencing a continuing observed and inferred decline in (iii) area, extent, and quality of habitat.

C: Small and declining number of mature individuals

Not applicable.

Not applicable. Number of mature individuals is unknown.

D: Very small or restricted population

Meets Threatened, D2.

Meets Threatened, D2. Restricted to an IAO of 4 to 20 km² and < or = 5 locations and it faces an uncertain future in a site negatively impacted by human activities and is thus capable of becoming extinct, extirpated or critically endangered in a very short period of time.

E: Quantitative analysis

Not applicable.

Not applicable. Analysis not conducted.

If a species is proposed as Special Concern, Data Deficient, Extirpated or Extinct, list the applicable guidelines, examples, or other considerations from O&P Appendix E3.

COSEWIC history

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) was created in 1977 as a result of a recommendation at the Federal-Provincial Wildlife Conference held in 1976. It arose from the need for a single, official, scientifically sound, national listing of wildlife species at risk. In 1978, COSEWIC designated its first species and produced its first list of Canadian species at risk. Species designated at meetings of the full committee are added to the list. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. SARA establishes COSEWIC as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process.

COSEWIC mandate

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. Designations are made on native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fishes, arthropods, molluscs, vascular plants, mosses, and lichens.

COSEWIC membership

COSEWIC comprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non-government science members and the co-chairs of the species specialist subcommittees and the Aboriginal Traditional Knowledge subcommittee. The Committee meets to consider status reports on candidate species.

Definitions (2024)

Wildlife Species

A species, subspecies, variety, or geographically or genetically distinct population of animal, plant or other organism, other than a bacterium or virus, that is wild by nature and is either native to Canada or has extended its range into Canada without human intervention and has been present in Canada for at least 50 years.

Extinct (X)

A wildlife species that no longer exists.

Extirpated (XT)

A wildlife species no longer existing in the wild in Canada, but occurring elsewhere.

Endangered (E)

A wildlife species facing imminent extirpation or extinction.

Threatened (T)

A wildlife species likely to become endangered if limiting factors are not reversed.

Special Concern (SC)^*

A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats.

Not at Risk (NAR)^**

A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.

Data Deficient (DD)^***

A category that applies when the available information is insufficient (a) to resolve a species’ eligibility for assessment or (b) to permit an assessment of the species’ risk of extinction.

*

Formerly described as “Vulnerable” from 1990 to 1999, or “Rare” prior to 1990

**

Formerly described as “Not In Any Category”, or “No Designation Required”

***

Formerly described as “Indeterminate” from 1994 to 1999 or “ISIBD” (insufficient scientific information on which to base a designation) prior to 1994. Definition of the (DD) category revised in 2006

The Canadian Wildlife Service, Environment and Climate Change Canada, provides full administrative and financial support to the COSEWIC Secretariat.

Wildlife species description and significance

Name and classification

Valley Grasshopper (Oedaleonotus enigma) was first described in 1876 from specimens collected in Santa Barbara, California (the type locality).

Current classification:

Class: Arthropoda

Order: Orthoptera

Family: Acrididae – grasshoppers, short-horned grasshoppers

Genus: Oedaleonotus

Species: Oedaleonotus enigma (Scudder 1876)

Subspecies in Canada: None.

Common names:

English: Valley Grasshopper

French: Criquet énigmatique

Indigenous: None known.

Synonyms and notes:

In the early literature (for example, Scudder 1876; Bruner 1893), there was some taxonomic disagreement that resulted in numerous synonyms (see synonym list). However, for the past 100 years, Oedaleonotus enigma has been a long-standing taxonomic entity, and there are no disputes in the literature or amongst orthopteran taxonomists.

The following are synonyms of Valley Grasshopper:

Caloptenus flavolineatus Bruner 1893

Melanoplus collaris Scudder 1878

Melanoplus jucundus (Scudder 1876)

Pezotettix enigma Scudder 1876

Pezotettix jucundus Scudder 1876

Genetic/molecular data:

Most species have a unique barcode index number (BIN). The DNA barcoding process enables specimens to be differentiated based on their BIN via comparison to the online barcode library (for further information on barcoding methods, see Ratnasingham and Hebert 2007, 2013; BOLD Systems 2023). Twelve Valley Grasshopper specimens from Oregon, Idaho, and California (none from B.C.) have been DNA barcoded using the mitochondrial cytochrome oxidase-1 (CO1) gene (BOLD Systems 2023). Results from barcoding (that are publicly accessible; BIN BOLD: ABV1951) show all specimens of Valley Grasshopper have the same BIN (BOLD Systems 2023).

Description of wildlife species

Valley Grasshoppers (Figure 1) are of typical grasshopper form, and characterized by slender bodies, large powerful hind legs for jumping, chewing mouth parts, and lengthwise folding wings. The species grows and develops by gradual metamorphosis through three life stages: egg, nymph (with six separate immature forms called instars), and adult. Gradual metamorphosis refers to insect development where the nymphs are smaller versions and look like adults, progressively getting larger with each successive moult, and reaching sexual maturity as an adult at their final moult.

Figure 1. Adult Valley Grasshopper (Oedaleonotus enigma), short-winged form. Note the primary distinguishing features are a narrow, conspicuously white to cream-coloured band on the anterior (front) edge of the pronotum; the hindleg femur is characterized by distinct dark brown chevrons separated by tan lines, and the blue hindleg tibia. Specimen collected at Osoyoos West Bench on September 8, 2023, and deposited at the Royal Saskatchewan Museum in Regina, Saskatchewan. Photo by Ryan Oram (with permission).

The morphological descriptions below are summarized from Bruvsen (1972), Pfadt (1994), Capinera et al. (2004), VanDyk (2023), and photographs posted to iNaturalist (2024).

Adult. Valley Grasshopper is a relatively large grasshopper species. The male body length is 17.5 to 21.5 mm and female body length is 19.0 to 24.0 mm (males are typically smaller than females). The body colour is yellow and the pronotum^{Footnote 1}, tegmen^{Footnote 2}, and femur^{Footnote 3} can have orange or black markings. The primary distinguishing features (Figure 1) include a thick-bodied hump-back appearance with a slightly elevated pronotum; a narrow, conspicuous white to cream-coloured band on the anterior edge of the pronotum; a hind femur with distinct dark brown chevrons separated by tan lines; and a blue hind leg tibia.

Adults show wing dimorphism: the tegmina can be short or long. Short tegmina are as long as or longer than the pronotum with even shorter, nonfunctional hind wings which limits the grasshopper’s mobility because it cannot fly. The tegmina can also be long, with long functional hindwings and the grasshopper can then fly.

Nymphs lack the morphological characters of adults, such as fully developed wings, genitalia, and body sclerotization, and most notably the distinct white band at the edge of its pronotum (the distinguishing feature used to confirm identification). The body length of the first instar is 4.0 to 4.8 mm and final (sixth) instar is 9.5 to 11.7 mm. The colour patterns of immature stages vary from brownish cream to brownish green. Detailed morphological descriptions and photos that show colour patterns of the immature stages are found in Pfadt (1994).

Eggs are laid in groups (called pods) held together by a frothy secretion that forms a protective covering when dry. There are 16 to 22 eggs in a Valley Grasshopper egg pod. Females oviposit pods horizontally 3-6 mm below the soil surface. Individual eggs are elongated (4.8-5.2 mm long), olive tan in colour (resembling brown rice), and are protected with a small foam plug.

Designatable units

Valley Grasshopper is being assessed as one designatable unit. There is no evidence of discreteness or evolutionary significance within the Canadian population. There are no described subspecies or evidence of morphological, behavioural, or genetic structuring. The species occurs within the Western Interior Basin terrestrial ecozone of Canada (ESTR Secretariat 2014).

Special significance

Valley Grasshopper is of interest to entomologists due to its rarity, the first record in Canada being from 2010. The species appears to be closely associated with the Antelope-brush (Purshia tridentata) and sagebrush (various species of Artemesia) ecological communities of the southern Okanagan Valley. This region contains numerous species that are rare and at risk in the province and in Canada (CDC 2023). This grasshopper, like numerous other arthropod species unique to this region, can be considered one of several focal species representing the sensitivity and uniqueness of these grasslands in Canada.

Aboriginal (Indigenous) knowledge

Aboriginal traditional knowledge (ATK) is relationship-based. It involves information on ecological relationships between humans and their environment, including characteristics of species, habitats, and locations. Laws and protocols for human relationships with the environment are passed on through teachings and stories, and Indigenous languages, and can be based on long-term observations. Place names provide information about harvesting areas, ecological processes, spiritual significance, or the products of harvest. ATK can identify life history characteristics of a species or distinct differences between similar species.

Cultural significance to Indigenous Peoples

There is no species-specific ATK in the report. However, Valley Grasshopper is important to Indigenous Peoples who recognize the interrelationships of all species within the ecosystem.

Distribution

Global range

Globally, Valley Grasshopper ranges in western North America from extreme southern British Columbia (B.C.), south through eastern Washington, Oregon, Idaho, Nevada, Montana, west to southern California, and northern Mexico, with potentially disjunct subpopulations in Utah (Figure 2) (Capinera et al. 2004; iNaturalist 2024). The global range is approximately 1,500,000 km².

Figure 2. Global range of Valley Grasshopper (Oedaleonotus enigma), as portrayed by documented occurrences. Data from iNaturalist (2024) and GBIF (2024). Note that the range is known to extend into the Mexican states of Baja California and Sonora; however, no occurrence from them was available for mapping. Map prepared by Alain Filion (COSEWIC Secretariat).

Canadian range

In Canada, Valley Grasshopper has a restricted range and occurs in extreme southern B.C. within some of the hottest and driest areas of Canada. There is one known subpopulation located on untitled^{Footnote 4} provincial land within the Osoyoos area and adjacent to the international border (Figure 3). There are no historical^{Footnote 5} or locationally vague^{Footnote 6} records of the grasshopper in Canada (Table 1).

Valley Grasshopper does not appear to depend on a specific host plant (Pfadt 1994), although the species appears restricted to the low elevation, valley bottoms with Antelope-brush, Big Sagebrush (Artemisia tridentata), and other plant species indicative of these shrub-steppe plant communities (see Habitat). There are likely additional factors that limit the grasshopper’s geographic range (see Limiting factors). Less than 1% of the global range of Valley Grasshopper is in Canada.

Valley Grasshopper records in Canada date from 2010 to 2023 and total nine specimen/sight records (Table 1). The species was first collected in Canada in 2010 from pitfall traps set on untitled provincial land (referred to as Osoyoos West Bench) adjacent to the international border. Trap contents were sorted (Heron unpubl. data), and Miskelly (2012) confirmed the record. Enquiries made to various regional and national entomological collections have not revealed additional collections (see Collections examined). Historically, Osoyoos West Bench has not been well surveyed for arthropods, unlike other well-known parks and ecological reserves in the area (Cannings pers. comm. 2024). Focus on inventory for this property shifted in 2009, after the Town of Osoyoos expressed interest in developing the habitat for urban housing (Dyer pers. comm. 2023) (see Habitat trends). The grasshopper’s Canadian range does not appear to have expanded since it was first documented at Osoyoos West Bench in 2010, which suggests that the species’ occurrence there is not part of a recent and ongoing northward range expansion and that the species has long been established in Canada.

Figure 3. Known and potential Canadian range of Valley Grasshopper (Oedaleonotus enigma), showing 2 km X 2 km index of area of occupancy squares (IAO) and the potential EOO (extent of occurrence). Map prepared by Alain Filion (COSEWIC Secretariat).

 

Grasshoppers are surveyed by hand-collection using a sweep net or by pitfall traps, and the surveys for Valley Grasshopper are mapped in Figure 4. Orthoptera-specific hand-collection wandering transect^{Footnote 7} surveys within the potential range of Valley Grasshopper were completed in 2021, 2023, and 2024. The wandering transects were a minimum of 15 minutes of search effort per site, whereby every orthopteran encountered was collected (euthanized). In 2021, 157 sites (minimum 500 m apart) with a minimum of 15 minutes of search effort at each site was completed by two surveyors from August 3 to September 10, for a total of 78.5 person-hours (Heron unpubl. data). In 2023, grasshopper surveys were completed in preparation for this status report with these same methods. A total of 75 sites (minimum 500 m apart) were surveyed by 1 to 4 surveyors for a total of 98 person-hours between September 5 and September 13 (Heron unpubl. data). In 2024, surveys were again completed at an additional 20 sites, with approximately 66 person-hours surveyed between September 10 and September 12 (Gelling unpubl. data). Additional pitfall trap search effort is tabulated in Table 2.

Figure 4. Search effort for Valley Grasshopper (Oedaleonotus enigma). Map prepared by Alain Filion (COSEWIC Secretariat).

The southern Okanagan Valley has long been the focus of intensive entomological collection because of the high density of nationally rare insect species. Historically, this work was primarily done by entomologists and more recently by citizen scientists. Citizen science web platforms, such as iNaturalist, BugGuide, and Facebook, are emerging as important avenues for documenting species occurrences by non-professionals, especially where photographic identification is reliable. There are over 1,000 grasshopper records posted to iNaturalist from the southern Okanagan Valley (iNaturalist 2024), and only two of these observations are Valley Grasshopper, both recorded at Osoyoos West Bench (Table 1).

Population structure

The population structure of Valley Grasshopper in Canada has not been studied. There is no evidence that this species relies on a specific host plant (Pfadt 1994); therefore, subpopulation structure may not be defined by host plant communities alone (see Habitat). Taking into account data from other grasshoppers, they may be able to fly up to 1 km between habitat patches over the lifespan of an individual grasshopper (see Dispersal and Rescue effect), and NatureServe recommends a 1 km separation distance in both suitable and unsuitable habitat for defining occurrences of Valley Grasshopper, which are roughly equal to subpopulations (NatureServe 2024). Using this separation distance, there are possibly two subpopulations, given that a single record southeast of the main cluster of records is separated by about 1.3 km. However, it is assumed that the species does occur in the intervening area, and therefore all records are assumed to be of a single subpopulation.

Extent of occurrence and area of occupancy

Current EOO

Extent of occurrence (EOO) within Canada is 4 to 9.3 km². The minimum EOO, as measured by a polygon around all known collection sites, is <1 km²; the value of 4 km² for the low end of the range is used as it matches the lowest possible index of area of occupancy. The high end of the range, 9.3 km², is a polygon around potential habitat in the South Okanagan Grasslands Protected Area and the Sage and Sparrow Conservation Area (that is, habitat <700 m elevation; Figure 3); these habitats have not been thoroughly surveyed and the species may occur there.

Current IAO

Index of area of occupancy (IAO) based on known records is 4 km² (Figure 3). The true value is likely higher. When adjacent habitat within the South Okanagan Grasslands Protected Area and the Sage and Sparrow Conservation Area is included, the value is 20 km² (Figure 3).

Fluctuations and trends in distribution

There is no information on fluctuations and trends in the distribution of Valley Grasshopper in Canada. Elsewhere in the species’ range, it does not appear to experience fluctuations in distribution.

Biology and habitat use

Information on the biology, life cycle, and reproduction of Valley Grasshopper is summarized from general references (for example, Preston-Mafham 1990; Pfadt 1994; Capinera et al. 2004; VanDyk 2023; iNaturalist 2024).

Life cycle and reproduction

The Valley Grasshopper has an annual life cycle. The species overwinters as an egg (Aug/Sept to April) and hatches as a nymph in the early spring (April/May). Nymphs grow by gradual metamorphosis through six instars (moults) from May through August before they reach their adult form in early August. Adults are active from early August through late September, and mating and oviposition occurs during this time.

The mating and courtship behaviour of Valley Grasshopper has not been studied. However, the behaviour involves song through stridulation and is well-documented in the family Acrididae. Stridulation occurs when the grasshopper moves the inner surface of the hindleg femur across serrations situated on the folded front wing (tegmen). The serrations vary in location, number, and shape to create a species-specific song. Males produce three and up to five different song types that vary in the form of the pulse (the whole song played during stridulation), intensity of sound (loudness), and frequency of repetition (Brown 1990).

In general, male song can be categorized as normal (single or groups of males sing to attract females), courtship (females produce a stridulatory response to the male song and orientation towards the male), or copulation. Mating is likely to occur more than once, although females within 24 hours of oviposition typically do not respond to male calling.

In many species of grasshoppers, the hindwings have stiff veins that make a crackling sound (crepitation) when in flight; however, it is unknown what role, if any, this sound plays in Valley Grasshopper mating and courtship behaviour. Additional information is found in Gwynne and Morris (1983), Brown (1990), and Preston-Mafham (1990).

Mature females have well-developed and hard ovipositors that allow them to dig a deep chamber in the ground for egg deposition. The ovipositor is used to manipulate egg and pod placement, and cap egg pods with froth for protection (Thompson 1996). Oviposition has not been observed in British Columbia. Eggs develop within the soil to an advanced embryonic stage until temperatures drop and they enter diapause for the winter. Valley Grasshoppers hatch from overwintered eggs early in the spring. Hatching has not been observed in B.C.; however, in southern parts of its range, they appear to hatch in the morning at air temperatures of 7.2° to 32.2°C and soil temperatures of 24.0 to 37.0°C (Pfadt 1994).

Valley Grasshopper eggs hatch earlier than those of most other grasshopper species. The nymphs grow slowly (likely due to cooler spring temperatures), have six instar stages, which is more stages than the typical grasshopper (most grasshoppers have five instars), and become adults in August. There is a 1:1 proportion of males to females (Pfadt 1994). Temperature likely influences the proportion of short- or long-winged forms in a subpopulation (see Morphological description), and this proportion varies between years (Pfadt 1994). Temperature trials in laboratory settings show that warmer temperatures (constant 37.8°C) result in more short-winged adults, and cooler temperatures (constant 26.7°C) result in more long-winged adults. Some years are all short-winged and other years the proportion is 50% long-winged/short-winged (Pfadt 1994).

Habitat requirements

Valley Grasshopper habitat at Osoyoos West Bench (Figure 5) and at the adjacent South Okanagan Grasslands Protected Area and the Sage and Sparrow Conservation Area occurs in a large area of grassland habitat that connects the southwest end of the Okanagan Valley along the international border with the southeast end of the Similkameen Valley (see Figure 3). The lower elevation (< 700 m) areas are part of the Bunchgrass (BG) biogeoclimatic zone^{Footnote 8} Okanagan Very Dry Hot Bunchgrass Variant (BGxh1) and include some of the hottest and driest habitats in the province. The dominant shrubs are Big Sagebrush, and Antelope-brush, with some Common Rabbit-bush (Ericameria nauseosa var. speciosa). The dominant forbs and grasses are Bluebunch Wheatgrass (Agropyron spicatum), Prickly Pear Cactus (Opuntia fragilis), Needle-and-thread Grass (Hesperostipa comata), June Grass (Koeleria macrantha), Sandberg’s Bluegrass (Poa sandbergii), and Two-form Pussytoes (Antennaria dimorpha) (Meidinger and Pojar 1991; CDC 2024). In general, at climax conditions the bunchgrass ecosystems are characterized by a cover of 10% to 15% shrubs, 60% bunchgrasses, and 25% to 35% cryptogams^{Footnote 9}; widely spaced bunchgrasses and a well-developed cryptogam crust (Meidinger and Pojar 1991).

Figure 5. Osoyoos West Bench untitled provincial land facing west to the South Okanagan Grasslands Protected Area (higher hills in the background of the photo). The darker grey areas are where wildfire burned in August 2023. Photo taken September 8, 2023, by Jennifer Heron.

In Canada, the BGxh1 covers approximately 22,780 ha and includes some of the most at-risk ecological communities in the country (Iverson 2012; CDC 2024). The ecological communities within Osoyoos West Bench specifically are the Antelope-brush/Needle-and-thread Grass (Purshia tridentata / Hesperostipa comata) ecological community, the Antelope-brush/Bluebunch Wheatgrass (Purshia tridentata / Pseudoroegneria spicata) ecological community, and the Big Sagebrush / Bluebunch Wheatgrass ecological community. These communities occur at an elevation < 1,000 m asl (above sea level) and have a reduced relief in comparison with surrounding steeper areas (CDC 2024).

Valley Grasshopper uses shrubs such as Big Sagebrush for roosting and mating. The grasshopper has also been observed using the exotic Prickly Russian Thistle (Salsola tragus) for roosting (Pfadt 1994). The soil type or microhabitat used for oviposition has not been studied, but it most likely has a high component of sand. The soils at Osoyoos West Bench are > 50% sand.

Movements, migration, and dispersal

Little is known about the dispersal behaviour of Valley Grasshopper. The species is mobile, and both short- and long-form winged adults and late-instar nymphs will disperse in search of forage vegetation (Pfadt 1994). The grasshopper has evasive flight behaviour like other grasshoppers. Adults capable of flight evade predators or potential threats by flying away silently at a height of 0.10 to 0.25 m for 1.2 to 2.4 m straight. When landing, they turn and either face directly or diagonally away from the pursuer. Flightless adults can jump 0.6 to 2.4 m; larger grasshoppers are able to jump farther than smaller ones (summarized from Pfadt 1994).

In other parts of its global range, studies undertaken to assess Valley Grasshopper abundance have shown that, when in high abundance, the nymphs move together in bands of 17 to 25 individuals/metre (Pfadt 1994). This movement may be in all directions or in one direction, depending on the topography. Movements also take place from abandoned fields and rangeland to irrigated crops. Long-winged individuals will fly to new areas; however, the dispersal distance of long-winged adults has not been studied (Pfadt 1994). Temperature also plays a role in grasshopper movement, because it influences the relative proportions of long- and short-winged individuals, with only long-winged adults able to fly (Pfadt 1994). NatureServe (2024) considers that the Valley Grasshopper is unlikely to disperse farther than 1 km over its lifespan (based on element occurrence separation distance guidelines); however, this is a general guideline and not species-specific (NatureServe 2002). Valley Grasshopper does not migrate.

Interspecific interactions

Diet

Valley Grasshopper is a polyphagous herbivore, feeding on forbs, shrubs, and to a lesser extent, on grasses. Both nymphs and adults share a similar diet (see Table 3). In high abundance, the species is known to move from abandoned fields and rangeland, to irrigated crops (Pfadt 1994). When food is scarce, including during drought conditions, Valley Grasshopper will feed on dead or dying plant material, dead insects, and other material such as animal feces, fungi, lichens, and fruit (Pfadt 1994; Capinera et al. 2004).

Predators and competitors

Vertebrate predators are considered the major driving force for some of the chemical defences that have evolved within the Orthoptera (Preston-Mafham 1990). Grasshoppers are a protein-rich food source for vertebrates (Preston-Mafham 1990; Capinera et al. 2004). Birds are a major predator of grasshoppers (Preston-Mafham 1990).

Digger wasps (Crabronidae and Sphecidae) may regulate grasshopper populations, as shown by a study in Montana grasslands (O'Neill 1995). Several species of square-headed wasps (Tachysphex spp.) are specialist predators on early-instar grasshoppers. Tachysphex pompiliformis has been observed preying on Valley Grasshopper in Idaho, where it may have reduced Valley Grasshopper nymph density from 20 to 30 nymphs/m² in early June to 1 nymph/m² in late June (Newton 1956).

Egg predators include common field crickets (Gryllus spp.), which can consume up to 50% of grasshopper eggs in an area (Government of Alberta 2023). The larvae of the genus Epicauta in the blister beetle family (Meloidae) are specialized predators of grasshopper eggs (Pinto 1991). In some areas, they have been reported destroying approximately 10% (Parker and Wakeland 1957) to up to 80% of grasshopper egg pods (Government of Alberta 2023). Bee flies (Bombyliidae) can also consume 80% of egg pods (Government of Alberta 2023). Some mite species (Acariformes) are predaceous on grasshopper eggs and may have an impact on grasshopper subpopulations (Belovsky et al. 1997).

There are numerous generalist arthropod predators of Orthopterans, including spiders (Aranae), predatory beetles (for example, tiger beetles and ground beetles [Coleoptera: Carabidae]), robber flies (Diptera: Asilidae), ants (Hymenoptera: Formicidae), and many predatory wasps (Hymenoptera) (Preston-Mafham 1990).

Host/parasite/disease interactions

Interspecific associations with grasshoppers come from their parasites and parasitoids. Several groups of Diptera (for example, Sarcophagidae, Anthomyiidae, Tachinidae, Nemestrinidae) and Hymenoptera (for example, Scelionidae) are parasitoids of grasshoppers (Smith 1940; Smith and Finlayson 1950; York and Prescott 1952; Rees 1985; Przybyszewski and Capinera 1991; Laws and Joern 2012). Egg and nymphal parasites of the genus Scelio (Hymenoptera: Scelionidae) infest 5% to 50% of grasshopper eggs (Government of Alberta 2023). Other parasites include fly larvae (Diptera) and threadworms (Nematoda). The impact of mites on most grasshopper species is not well documented; however, overall, mites are important parasites of grasshoppers (Belovsky et al. 1997). Mites are commonly found on adult grasshopper wings, although they appear to have minimal impact to the individual.

There is a report of an orthopteran-specific hairworm (Nematomorpha) parasite that alters adult grasshopper behaviour and induces them to jump into fresh water, thus killing them (Biron et al. 2005). Numerous nematodes (Nematoda) are grasshopper-specific parasites, including some used as biological control agents (Baker and Capinera 1997).

Fungal and bacterial pathogens are important factors affecting Orthoptera (Bucher and Stephens 1957; Streett and McGuire 1990; Glogoza and Weiss 1997), and one species (and probably the most important), namely Entomopthora grylli, is apparently specialized for grasshoppers and crickets (Pickford and Riegert 1964; Erlandson et al. 1988). It has been reported that the microsporidian parasite Nosema locustae can reduce a grasshopper population by 60% within a year (Ewen and Mukerji 1980; Government of Alberta 2023). The nymphal stages appear to be more susceptible than adults to fungal infection (Kistner and Belovsky 2013). The status of these pathogens in grasshopper populations, in general, in the range of Valley Grasshopper is undocumented.

Physiological, behavioural, and other adaptations

Valley Grasshopper adaptations that are potentially relevant to threats and status assessment include their dispersal ability (see Movements, Migration, and Dispersal) and the wide range of forage preferences at both the nymphal and adult life stages (see Diet). It is uncertain how Valley Grasshopper responds to wildfire; however, as with other grasshoppers, there is likely high potential for the species to recolonize burned areas over time, given a source subpopulation.

Limiting factors

Limiting factors are generally not human-induced and include intrinsic characteristics that make the species less likely to respond to conservation efforts. Limiting factors may become threats if they result in population decline. The main limiting factors for Valley Grasshopper are likely a combination of the following:

Vulnerability to weather patterns

Weather patterns (for example, temperature, rainfall, snowfall, humidity) are the main drivers of grasshopper abundance (Pfadt 1994; Capinera et al. 2004), with spring and fall temperatures being the most important factors (Pfadt 1994). Hot spring temperatures mean that the overwintering eggs can mature sooner and hatch sooner, thereby growing to adults, which can mate, and lay eggs sooner. Plants also grow earlier and faster when the weather is warmer. Valley Grasshopper nymphs appear to be hardy, with freezing temperatures having little effect on nymph survival (Pfadt 1994).

Fall temperatures can limit the number of eggs laid (for example, colder, and wetter fall weather will cause a decrease in egg abundance), and the rate of embryonic development within the egg is influenced by fall temperatures. Warmer and longer fall weather means the embryo within the egg has longer to develop before entering diapause (when growth ceases), and in the spring, the grasshopper nymph will hatch sooner (Belovsky et al. 2016; Government of Alberta 2023).

Native predators and parasites

After weather, natural enemies are considered the next greatest limiting factor to grasshopper abundance. The predators and parasites discussed under Interspecific interactions could all be included as limiting factors.

Population sizes and trends

The sections below provide rationale for the population information presented in the Technical Summary.

Data sources, methodologies, and uncertainties

The methods used to gather data on Valley Grasshopper in Canada (for example, wandering transects, pitfall traps, photographs) from 2010 to 2024 are insufficient to derive population estimates.

Abundance

There are nine observations/specimens of Valley Grasshopper recorded from Canada (Table 1), and these data are insufficient to estimate population abundance in Canada.

Fluctuations and trends

Continuing decline^{Footnote 10} in number of mature individuals:

There is likely a decline in number of mature individuals based on a decline in habitat quality at Osoyoos West Bench from long-term camping, the accumulation of garbage, all-terrain vehicle use, and other recreational use, as well as the spread of non-native/invasive plants that decrease the spatial area of bare ground.

Evidence for continuing decline (1 generation or 3 years, whichever is longer, usually up to 100 years):

No information available.

Evidence for continuing decline (2 generations or 5 years, whichever is longer, usually up to 100 years:

No information available.

Evidence for past decline (3 generations or 10 years, whichever is longer) that has either ceased or is continuing (specify):

No information available.

Evidence for projected or suspected future decline (next 3 generations or 10 years, whichever is longer, up to a maximum of 100 years):

No information available.

Long-term trends:

No information available on the long-term trends of the Canadian population.

Population fluctuations, including extreme fluctuations:

The natural subpopulation fluctuations in grasshoppers are a result of factors such as parasites, predators, and the previous years’ weather. In the core of its range in the United States, Valley Grasshopper apparently experiences extreme fluctuations, as it is reported to reach “outbreak” numbers with densities as high as > 24 adults/m² (Pfadt 1994) reported. However, because of too few specimens or observations in Canada, there is insufficient information to estimate population fluctuations or trends for the species in Canada.

Severe fragmentation

A taxon can be severely fragmented if most (> 50%) individuals or most (> 50%) of the total area occupied (as a proxy for number of individuals) is in habitat patches that are both (a) smaller than would be required to support a viable population and (b) separated from other habitat patches by a distance larger than the species can be expected to disperse. Continued observations of Valley Grasshopper at Osoyoos West Bench suggest there is sufficient habitat for a viable population, despite ongoing threats to habitat quality. Taking into account the species’ persistence, its habitat does not appear to meet the definition of severe fragmentation.

Rescue effect

The closest confirmed record of Valley Grasshopper is across the international border in Wenatchee, Washington (iNaturalist 2024), which is approximately 180 km south of Osoyoos West Bench. However, habitat adjacent to the international border (in Washington) at Osoyoos appears to be suitable for Valley Grasshopper, and the species may occur there. The Canadian population may experience some immigration from subpopulations adjacent to the international border, and vice versa.

Threats

Historical, long-term, and continuing habitat trends

The Antelope-brush and sagebrush ecological communities in the lower elevation (< 700 m) valley bottoms of the Okanagan and Similkameen areas have declined in spatial area and quality, and have become substantially fragmented since the 1800s. The Antelope-brush/Needle-and-thread Grass ecological community declined in area from 9,863 ha in 1800 to 3,217 ha in 2009: a loss of 67.4% of the original extent of this ecosystem (Iverson 2012). After European settlement, these grasslands were initially used for livestock grazing, and eventually converted to orchards, vineyards, housing, and other forms of development. From 1995 to 2003, 1,077 ha of Antelope-brush/Needle-and-thread Grass was lost to habitat conversion at an average rate of 134.6 ha/year (Iverson 2012). From 2003 to 2008, only 82 ha of habitat were lost to development, at an average rate of 16.4 ha/year (Iverson 2012). Trends in sagebrush ecological community loss are not as well documented, but much of these grasslands are used for livestock grazing, recreational all-terrain vehicle use, and incremental development such as roads, corrals, or illegal camping. Although Valley Grasshopper has not been recorded throughout much of this range, these habitat trends are applicable to Osoyoos West Bench and the surrounding converted habitat that historically may have held additional subpopulations of this species.

Trends in habitat loss continue due to high pressure to develop untitled provincial Crown land and natural areas for housing, commercial, and agricultural use. For example, agricultural conversion of orchards and other fruit trees to vineyards is prevalent throughout the region, and impacts to the landscape’s wildlife habitat capacity are projected to continue (Mullinix et al. 2021). Vineyard agriculture is typically more land-intensive, with fewer weeds and natural pockets of habitat. The rich, sandy, and well-drained soils that support the Antelope-brush ecological communities are considered an indicator for high grape crop production and specifically targeted by the wine industry for development (COSEWIC 2012; Dyer pers. comm. 2018). These trends will continue to place more pressure on Antelope-brush ecological communities, particularly those on untitled provincial Crown land that can then be sold to the private sector for further land development.

Current and projected future threats

There is little information on specific threats to Valley Grasshopper, and most threats are based on habitat trend information known for the south Okanagan and Similkameen valleys. The cumulative loss, degradation, and fragmentation of the bunchgrass ecological communities at Osoyoos West Bench and adjacent habitats are the primary threats to Valley Grasshopper. The biggest threat is the potential for this habitat to be lost to urban development, and ongoing cumulative threats from intensive all-terrain vehicle use, long-term camping, garbage accumulation, and soil erosion.

The nature, scope, and severity of these threats has been described in Appendix 1, following the IUCN-CMP (International Union for Conservation of Nature – Conservation Measures Partnership) unified threats classification system (see Salafsky et al. 2008 for definitions and Master et al. 2012 for guidelines). The threat assessment process consists of assessing impacts for each of 11 main categories of threats and their subcategories, based on the scope (proportion of population exposed to the threat over the next 10-year period), severity (predicted population decline within the scope during the next 10 years or 3 generations, whichever is longer, up to approximatelyv100 years), and timing of each threat. The overall threat impact is calculated by considering the separate impacts of all threat categories, and can be adjusted by the species experts participating in the threats evaluation.

The overall threat impact for Valley Grasshopper is high, corresponding to a projected decline of between 10% and 70% over the next 10 years. These values are to be interpreted with caution, as they may be based on subjective information, such as expert opinion, although efforts have been made to corroborate the scores with available studies and quantitative data.

Residential or commercial development (IUCN # 1; overall threat impact high)

1.1 Housing and urban areas (high impact)

Osoyoos West Bench is a large (> 350 ha) parcel of untitled provincial land. The town of Osoyoos has expressed an interest to the B.C. government in acquiring the property for the expansion of the adjacent housing development as part of the regional growth strategy (RDOS 2017). The entire Osoyoos West Bench is located within a Notation of Interest and Section 16 Map Reserve, which is a land tenure that serves to inform government and other tenure holders (or would-be tenure holders or developers) about the potential interest in a given parcel for environmental and conservation purposes. However, this notation does not protect the land from being sold, leased, or developed. The land is also within the working boundary of the proposed South Okanagan National Park Reserve, but until the park is established, this provides no formal protection. Further information is provided under Land Tenure and Ownership.

The lower to mid-elevation grasslands of the Okanagan Valley continue to be incrementally developed for urban and rural housing as the human population grows. The human population within this area has tripled every 30 to 40 years since 1940 (Jensen and Epp 2002). Projected human population growth for the Okanagan-Similkameen from 2016 to 2041, with an annual rate of 0.84%, is up to 13,000 new residents by 2041, not including on-reserve First Nations (Penticton Indian Band, Osoyoos Indian Band) (RDOS 2017).

Valley Grasshoppers require bare ground to lay their eggs (Pfadt 1994), and these types of soils tend to be absent from developed landscapes (for example, yards and gardens within housing or developed areas), which are often composed of relatively impervious surfaces (for example, concrete, gravel, manicured lawns). Some grasshopper species flourish in these anthropogenic habitats, while others, such as Valley Grasshopper, do not appear to maintain a presence.

1.2 Commercial and industrial areas (low impact)

This threat is applicable to unsurveyed potential habitat within some of the areas adjacent to Osoyoos West Bench. It may also affect natural habitat patches (for commercial buildings for crop storage, wine tasting, or fruit shops) on agricultural land.

Human intrusions and disturbance (IUCN # 6; overall threat impact low)

6.1 Recreational activities (low impact)

All-terrain vehicle (ATV) use and long-term camping (> two weeks) are the primary ongoing recreational activities detrimental to the Antelope-brush plant communities at Osoyoos West Bench. Extensive trampling of vegetation, garbage (including human waste), frequent campfires, and discarded camping equipment and garbage at the site all contribute to habitat degradation. There are numerous camper vans, trailers, and temporary structures on the property from April to October, and adverse impacts to habitat within 75 m of the main areas accessible by drivable roads. Valley Grasshopper uses herbaceous vegetation to forage upon, shrubs as shelter and as potential mating sites, and sandy soil to oviposit eggs. The above-mentioned recreational activities impact the integrity of these microhabitats and ultimately subpopulation abundance. People will also cut and burn these woody plants as campfire fuel.

The adjacent South Okanagan Grasslands Protected Area is large and there are hiking trails and old roads throughout the property, but much of the area is remote and inaccessible for day-use recreational users. The property is subject to occasional illegal ATV use, although access is challenging and this use is infrequent. Recreational use at South Okanagan Grasslands Protected Area is considered negligible.

Pollution (IUCN #9; overall threat impact low)

9.4 Garbage and solid waste (low impact)

Osoyoos West Bench has had large accumulations of garbage in certain areas, particularly due to long-term encampments established over the past five years. The site is frequently used by campers, who leave behind camping equipment, plastic wrappers, human waste, pallets, metal drums, defunct mechanical equipment, furniture, mattresses, and various building materials. There are at least 10 to 15 encampments, and over time each leaves behind garbage. Much of this garbage was cleaned up in fall 2024, and measures were put in place, such as a gate on the access road, to discourage future use of the site for camping and squatting. It seems likely that there will be further garbage deposition in the future, though perhaps not at the rate seen in the recent past.

Climate change and severe weather (IUCN # 11; overall threat impact low)

11.2 Droughts (low impact)

Climate change is a potential but poorly understood threat to Valley Grasshopper. Climate change, particularly an increase in the frequency and intensity of extreme and periodic climatic events such as droughts, could be a long-term threat to developing eggs (in the soil) and nymphs. Extensive and prolonged drought may impact plants and lessen the forage opportunities for insect growth.

Agriculture and aquaculture (IUCN # 2; overall threat impact unknown)

2.1 Annual and perennial non-timber crops (unknown impact)

The conversion of natural habitat to vineyards is a major threat to the lower elevation (< 700 m) valley bottom grassland habitats of the Okanagan areas (Iverson 2012). In particular, the Antelope-brush / Needle-and-thread Grass ecological community is targeted for acquisition by the grape production sector because it has ideal soil conditions for grape growth (COSEWIC 2012; Dyer pers. comm. 2018). Grape crops yield a higher return on investment than orchards or other forms of agriculture (see Habitat trends). In general, vineyards are intensively managed and use higher portions of the land base than many of the older orchards in the region, and this higher intensification means fewer pockets of natural habitat available for native insects, such as the Valley Grasshopper, among the agricultural fields.

Numerous private lands have small pockets of natural habitat, often too steep or rocky to plant an agricultural crop. These habitat refugia enable native insect populations to remain. Land is becoming more valuable in the Okanagan, and tourism demand is increasing, making it is becoming more economical to develop these habitat patches for either agricultural crops and/or infrastructure such as wine tasting rooms, restaurants, or bed-and-breakfasts (the infrastructure development is accounted for in Threat 1.1 and 1.2).

The habitat known to be occupied by Valley Grasshoppers seems more likely to be developed for housing than for agriculture. Because it is unknown whether other pockets of habitat that are occupied by Valley Grasshopper may be developed for agricultural use, the scope and therefore the threat is scored as unknown.

2.3 Livestock farming and ranching (unknown impact)

Livestock grazing occurs in Osoyoos West Bench and the adjacent South Okanagan Grassland Protected Area. Overgrazing leads to soil compaction, changes the nutrient content of the soil through urination and defecation, and reduces the survivorship of developing eggs. Valley Grasshopper persists at Osoyoos West Bench with the current grazing regime, although it is unknown if grazing impacts the species abundance at the site.

Natural system modifications (IUCN # 7; overall threat impact unknown)

7.1 Fire and fire suppression (unknown impact)

This threat is subdivided into two subcategories: fire and fire suppression. Fire suppression is scored under 7.3 (Other ecosystem modifications), but partially discussed here because of its contribution to wildfire intensity and severity.

Wildfire from lightning strikes is considered part of the natural ecosystem processes of the southern interior grasslands, although fire suppression programs over the past 100 years have altered the natural fire regime. Prior to European contact, frequent, low-intensity wildfires within the Ponderosa Pine and Bunchgrass ecosystems were more common with intervals of 4 to 50 years (low-severity surface fires) and at least 150 to 250 years for high-severity stand-initiating crown fires (ENV 1995). Fires were also ignited by First Nations Peoples to improve root crops and land stewardship (Iverson 2012; CBPF 2023).

Fire is a direct threat to Osoyoos West Bench and potential Valley Grasshopper habitat within the adjacent South Okanagan Grasslands Protected Area. Lightning strikes are frequent throughout the southern interior, and accidental fire by discarded cigarettes, unattended campfires, or vehicles (and hot engines) driving through dry vegetation are all plausible ignition scenarios at Osoyoos West Bench. In 2023, the Eagle Bluff wildfire burned from July 29 (first reported) to August 19 (fire under control) and consumed > 7,060 ha of grassland habitat within portions of South Okanagan Grasslands Protected Area, private lands (including private conservation lands), and Osoyoos West Bench (Figure 6). Provincial fire maps show the perimeter of the fire, which overlaps with the Canadian range of Valley Grasshopper as recorded in iMac (accessed May 2, 2024). When Osoyoos West Bench was visited in mid-September 2023 (after the wildfire was extinguished), the property had burned extensively; however, Valley Grasshopper adults were recorded within natural unburned areas at the site (Heron unpubl. data).

Impacts of wildfire on grassland grasshopper assemblages are complex. Adults are directly killed by fire, although depending on the intensity, severity, and burn mosaic, unburned areas in the landscape could be refuges for both adults and overwintering egg masses (in the soil). There are numerous studies on the impacts of grassland fires on grasshopper assemblages (for example, Evans 1984; Nadeau et al. 2006). In general, it appears grassland fires do not adversely impact grasshopper diversity or abundance in the long term, as long as there are sufficient nearby adjacent subpopulations and intact habitat for migration, and the burned habitat is allowed to naturally regenerate. The impacts of fire on Valley Grasshopper subpopulations have not been studied, but grass-feeding grasshopper species tend to rebound faster than forb-feeding species (Evans 1984), and Valley Grasshopper appears to be a forb- and grass-feeding species. It is unknown how long it would take an adjacent Valley Grasshopper subpopulation to recolonize a burned area and for its abundance to return to pre-fire numbers.

Figure 6. Recent fires in the vicinity of the Osoyoos West Bench. The southernmost burn is the Eagle Bluff fire from 2023 (K52318), which overlaps with Osoyoos West Bench (known range of Valley Grasshopper, Oedaleonotus enigma) and the South Okanagan Grasslands Protected Area. The Eagle Bluff fire crosses the Canada–United States border. Just north of the Eagle Bluff fire is the 2015 Testalinden Creek fire (K50615). East of that (northeast of Osoyoos Lake) is the Nk'Mip Creek 2021 fire (K52061). The smaller polygons between the two are also from 2015 fires (K50438 and K50619). Data from the B.C. Ministry of Water, Land and Resource Stewardship, Penticton office.

7.3 Other ecosystem modifications (unknown impact)

The cumulative effects of fire suppression activities (7.1) and the spread of non-native/alien plants (8.1) may be changing the quality and quantity of habitat available to Valley Grasshopper. These threats gradually change the habitat rather than directly kill or injure Valley Grasshopper individuals, which is why they are scored under this threat heading. However, over time these ecosystem modifications may reduce the number of oviposition sites, mating territories, and habitat structure necessary to maintain a viable subpopulation of Valley Grasshopper. Non-native Cheatgrass (Bromus tectorum), Dalmatian Toadflax (Linaria dalmatica), and other invasive plants form thick, dense mats, and decrease the amount of open bare ground. These can impact habitat quality for Valley Grasshopper oviposition and egg overwintering sites.

Fire suppression is considered an ecosystem modification and has resulted in a buildup of fuels (both live growth and dead organic matter) on the ground. When fires do occur, they are more intense, including stand-replacing fires, as opposed to less intense, patchy fires that leave some grassland ecological community patches intact. Reduced wildfire also leads to tree encroachment, which reduces the size and extent of bare soil and open sandy areas, due to shading and competition. Natural succession of both native and non-native plants may reduce females’ ability to access open bare ground. When plants grow into softer soil, the plant roots create thick mats that may make it difficult for females to find suitable oviposition sites. On the other hand, Valley Grasshopper does not appear to rely on a specific host plant, and more forage may benefit the species overall and lead to higher abundance. Overall, the impacts of fire suppression on Valley Grasshopper are unknown.

Invasive and other problematic species and genes (IUCN # 8; overall threat impact unknown)

8.1 Invasive non-native/alien species (unknown impact)

The overall impact of invasive plants on the Valley Grasshopper diet is unknown. The species is known to consume non-native species that are present in the Okanagan-Similkameen, such as Redstem Stork's-bill (Erodium cicutarium), Heart-podded Hoary Cress (Lepidium draba cited as Draba Mustard in Pfadt 1994), and Cheatgrass (Pfadt 1994). The species does not appear to consume the exotic Prickly Russian Thistle (Pfadt 1994), which is widely abundant in the Okanagan-Similkameen. These invasive plants may impact oviposition sites and other behaviours, which is discussed and scored under 7.3 (Other ecosystem modifications).

Pollution (IUCN # 9; overall threat impact unknown)

9.3 Agricultural and forestry effluents (unknown impact)

Valley Grasshopper (both immature and adult forms) is considered a rangeland pest in Oregon (Oregon Department of Agriculture 2022) and Idaho (USDA 2020). Nymphs hatch in the spring and develop through incomplete metamorphosis, growing and consuming vegetation during all these life stages. It is unlikely that Valley Grasshopper ever occurs at pest levels in Canada. In general, grasshopper outbreaks have not been monitored in the south Okanagan, and over the past few decades widespread grasshopper control has not been implemented (B.C. Ministry of Agriculture 2015). However, the use of small-scale application and chemical control to manage insect populations on private farms is left to the individual landowner/manager, and not tracked at a regional scale. Therefore, the scope and severity are unknown.

Number of threat locations

There are one to five locations of Valley Grasshopper. The rationale for the number of locations is:

• a minimum of one location based on housing development at Osoyoos West Bench. Most of this property where Valley Grasshopper is known to occur has the potential to be developed within the next 10 years. While there may be conservation set-asides established or maintained for imperilled species on the Osoyoos West Bench (based on the presence of plant species at risk, there are already three set-asides to protect from ATV use and grazing; at present these areas are < 0.5 ha each), a development could rapidly impact most or all of the population
• the spatial footprint of Osoyoos West Bench includes substantial bedrock and steep rocky cliffs (< 50 m height), old mining shafts, and other areas that may not be feasible for development. If these areas are suitable habitat for Valley Grasshopper and large enough to support the species, they potentially represent a second location
• a portion of the extant subpopulation is likely on the adjacent South Okanagan Grassland Protected Area and the Sage and Sparrow Conservation Area (although not confirmed), which is not part of the development area. In particular, areas of habitat that are <700 m in elevation are the most likely places to host the species. The South Okanagan Grassland Protected Area and the Sage and Sparrow Conservation Area experienced extensive wildfire in 2023, and the habitat quality for Valley Grasshopper remains unknown. The fire was patchy, and the habitat quality is likely variable, suggesting there could be a few locations in this area. These could represent a third, fourth, and fifth location

Protection, status, and recovery activities

Legal protection and status

Valley Grasshopper is not specifically listed or protected under provincial or federal legislation.

The grasshopper is known from one large parcel of untitled provincial land (Osoyoos West Bench) that is under review for acquisition by the Town of Osoyoos for future housing development (see Threats).

Valley Grasshopper is a candidate for listing as Identified Wildlife under the Forest and Range Practices Act and the Oil and Gas Activities Act, as part of the Identified Wildlife Management Strategy (IWMS). The IWMS goals are to “minimize the effects of forest and range practices on Identified Wildlife situated on Crown land.” Identified Wildlife are managed through the establishment of wildlife habitat areas (WHAs) and the implementation of general wildlife measures (GWMs) and wildlife habitat area objectives. If Valley Grasshopper was listed under this act, it would be eligible for WHA establishment.

In the United States, the species is not protected by any legislation.

Non-legal status and ranks

The conservation status ranks for Valley Grasshopper:

1. Global Status: G5 (Secure) (last reviewed 2000) (NatureServe 2024)
2. Canada National Status: N1 (NatureServe 2024)
3. B.C. provincial status: S1 (Critically Imperilled, pending review because it was last reviewed in 2015) (CDC 2023)
4. United States: N5 (Secure) (NatureServe 2024)
5. State ranks: Idaho S5 (Secure) (NatureServe 2024). All other jurisdictions where it is known to occur (Washington, Montana, Oregon, Wyoming, Utah, California) have no status rank (SNR)
6. Mexico: Not assessed
7. IUCN: Not assessed

Land tenure and ownership

The one subpopulation of Valley Grasshopper in Canada is known from untitled provincial land. The entire Osoyoos West Bench is located within a Notation of Interest and Section 16 Map Reserve, which is a land tenure (under the B.C. Land Act) that serves to inform government and other tenure holders (or would-be tenure holders or developers) about the potential interest in a given parcel for environmental and conservation purposes. However, this notation does not protect the land from being sold, leased, or developed. Similar habitat is within the adjacent South Okanagan Grasslands Protected Area (owned by the B.C. government and managed by B.C. Parks and Protected Areas), and Sage and Sparrow Conservation Area (owned and managed by the private non-government organization, The Nature Conservancy of Canada). It is likely the grasshopper occurs within these properties, although there are no confirmed records.

Both the known subpopulation and the potentially occupied habitat in South Okanagan Grasslands Protected Area and the Sage and Sparrow Conservation Area are within the working boundary of the proposed South Okanagan National Park Reserve (Figure 7). This working boundary was established in 2019 through a memorandum of understanding between the governments of Canada, British Columbia, and the Syilx Okanagan Nation (Parks Canada 2024). Should the park become established with these working boundaries, the Valley Grasshopper’s habitat would be protected. Until that time, the working boundaries do not provide any formal protection.

Figure 7. Working boundaries of the proposed South Okanagan National Park Reserve. Area containing the single known Valley Grasshopper occurrence circled in red. Map from Regional District of Okanagan-Similkameen (2023).

Recovery activities

This species is not part of any species-specific conservation activities. Non-government conservation organizations, such as the South Okanagan Similkameen Conservation Program (and affiliated organizations), work with private landowners towards protecting arthropod species at risk on private land. Should additional information become available on Valley Grasshopper, these organizations may be willing to initiate stewardship actions within their current management and outreach planning.

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Collections and databases examined/queried

• Canadian National Collection of Insects, Arachnids and Nematodes, Agriculture and Agri-Food Canada, Ottawa, ON (Lonsdale pers. comm. 2023) (no specimens of Valley Grasshopper in the collection)
• iNaturalist https://www.inaturalist.org/observations?taxon_id=153314 [accessed November 19, 2024]
• Royal Alberta Museum, Invertebrate Zoology, Edmonton, Alberta (Matthias Buck pers. comm. 2023) (no specimens of Valley Grasshopper in the collection)
• Pacific Forestry Centre, Natural Resources Canada, Victoria, British Columbia (John pers. comm. 2023) (no specimens of Valley Grasshopper in the collection)
• Royal British Columbia Museum, Victoria, British Columbia (Claudia Copley pers. comm. 2023) (Valley Grasshopper in the collection, see Table 1)
• Royal Saskatchewan Museum, Regina, Saskatchewan (Cory S. Sheffield) (no specimens of Valley Grasshopper in the collection)
• Spencer Entomological Collection, Beaty Biodiversity Museum, University of British Columbia, Vancouver, British Columbia (Needham pers. comm. 2023) (no specimens of Valley Grasshopper in the collection)
• Strickland Entomological Museum, Department of Biology, University of Alberta, Edmonton, Alberta, online database [accessed August 7, 2023] (no specimens of Valley Grasshopper in the collection)
• Summerland Research and Development Centre. Entomology Collection. Agriculture and Agri-Food Canada, Summerland, British Columbia (Nelson pers. comm. 2024) (no specimens of Valley Grasshopper in the collection)
• University of Calgary, Insects and Invertebrate Zoology Museum, Department of Biological Sciences, Calgary, Alberta (Swann pers. comm. 2023) (no specimens of Valley Grasshopper in the collection)
• VanDyk, J. (ed.) 2023. BugGuide.Net: Identification, Images, and Information for Insects, Spiders and Their Kin for the United States and Canada. Iowa State University. Website: https://bugguide.net [accessed April 12, 2024]
• Vickery, V.R., and D.K.M. Kevan. 1985. The grasshopper, crickets, and related insects of Canada and adjacent regions. Biosystematics Research Institute, Ottawa, Ontario. Publication Number 1777. 918 pp
• Wallis Roughley Museum of Entomology, Department of Entomology, University of Manitoba, Winnipeg (Gibbs pers. comm. 2023) (no specimens of Valley Grasshopper in the collection)

Authorities contacted

• Bunge, Sarah. Area Supervisor, Parks and Protected Areas, British Columbia Ministry of Environment and Climate Change Strategy, Penticton Office, Penticton, British Columbia
• Cannings, Syd. Species at Risk Biologist (retired), Canadian Wildlife Service, Environment and Climate Change Canada, Whitehorse, Yukon
• Copley, Claudia. Entomology Collections Manager, Royal British Columbia Museum, Victoria, British Columbia
• Dyer, Orville. Amphibians, Reptiles and Small Mammals Species at Risk Biologist (retired), Ministry of Environment and Climate Change Strategy, Penticton, British Columbia
• Gelling, Lea. Zoologist, British Columbia Conservation Data Centre, British Columbia Ministry of Water, Land and Resource Stewardship, Victoria, British Columbia
• Gross, Eric. Species at Risk Biologist. Canadian Wildlife Service, Environment and Climate Change Canada, Delta, British Columbia
• Leatham, Jamie. Ecosystems Biologist, Ministry of Water, Land and Resource Stewardship, Penticton, British Columbia
• Marks, Dawn. Ecosystems Biologist, British Columbia Ministry of Water, Land and Resource Stewardship, Penticton, British Columbia
• Needham, Karen. Curator of Entomology, Spencer Entomological Collection, Beaty Biodiversity Museum, University of British Columbia, Vancouver, British Columbia
• Nelson, Tyler. Research Technician, Agriculture and Agri-Foods Canada, Summerland, British Columbia
• Safford, Kirk. Conservation Specialist, British Columbia Parks and Protected Areas, Penticton, British Columbia
• Sheffield, Cory S. Curator of Invertebrates and Botany. Royal Saskatchewan Museum, Regina, Saskatchewan
• Symonds, Josie. Ecosystems Biologist, British Columbia Ministry of Water, Land and Resource Stewardship, Penticton, British Columbia
• Weston, Mark. Area Supervisor, Parks and Protected Areas, British Columbia Ministry of Environment and Climate Change Strategy, Penticton, British Columbia

Acknowledgements

Thank you to the B.C. Ministry of Water, Land and Resource Stewardship for providing time and resources to complete this report. The following people provided field support and scientific advice: Dawn Marks, Claudia Copley, Darren Copley, Kirk Safford, Orville Dyer, Sara Bunge, Mark Weston, Brenda Costanzo, Josie Symonds, Katie Calon, Jamie Leatham, Jeevan Sandhu, Lea Gelling, Paul Catling, James Miskelly, Julie Wray, Pascale Archibald, Kihan Yoon-Henderson, Madison Koshuba, Bruce Bennett, Joni Reimer, Adrienne Canty, Purnima Govindarajulu, and Mike Badry. Joni Reimer (Osoyoos Desert Centre) and Mark Weston (B.C. Parks) enabled access to the properties they manage. Claudia Copley (Royal BC Museum, Victoria) provided access to museum specimens, and Ryan Oram (Royal Saskatchewan Museum) took photographs of specimens. James Miskelly provided invaluable search effort and species advice and identification of specimens. Sarah Bayliff of the Nature Conservancy of Canada provided a KMZ file for the Sage and Sparrow Conservation Area. Review was provided by members of the Arthropods Specialist Subcommittee (Robert Buchkowski, Syd Cannings, Lisa Capar, Jeremy deWaard, Allan Harris, Colin Jones, Jayme Lewthwaite, Jessica Linton, Dawn Marks, Julia Mlynarek, Tyler Nelson, Jeff Ogden, Robert Pivar, Leah Ramsay, Brian Starzomski, Roger Gallant, and Dan Benoit).

Maps in this status report were prepared by Alain Filion (COSEWIC Secretariat). Funding for the preparation of this report was provided by B.C. Ministry of Water, Land and Resource Stewardship, and Environment and Climate Change Canada (COSEWIC Secretariat).

Biographical summary of report writer

Jennifer M. Heron is the provincial Invertebrate Conservation Specialist with the Conservation Science Section, B.C. Ministry of Water, Land and Resource Stewardship. She directs and manages the provincial approach to invertebrate conservation, including the development and implementation of provincial legislation, policy, procedures, and standards for conservation, and recovery of invertebrate species at risk, their habitats, and ecosystems, and actions to keep these species from becoming at risk. Her background includes an M.Sc. from the University of British Columbia. She has written/co-written numerous COSEWIC reports. Her interests include the native bees of western Canada and thermal spring invertebrates.

Appendix 1. Valley Grasshopper (oedaleonotus enigma) threats assessment in Canada

The classification below is based on the IUCN-CMP (International Union for Conservation of Nature–Conservation Measures Partnership) unified threats classification system. For a detailed description of the threat classification system, see Salafsky et al. 2008; Master et al. 2012; open standard 2016. Threats may be observed, inferred, or projected to occur in the near term. Threats are characterized here in terms of scope, severity, and timing. Threat “impact” is calculated from scope and severity. For information on how the values are assigned, see Master et al. (2012) and footnotes to this table.

Scientific name: Valley Grasshopper (Oedaleonotus enigma)

Date: September 25, 2024

Assessors: Jennifer Heron (report writer), John Klymko (Arthropods SSC Co-chair), Joanna James (COSEWIC Secretariat), Dawn Marks (B.C. Water, Land and Resource Stewardship) and review by Arthropods SSC.

Assigned overall threat impact: B = High

Impact adjustment reasons: None

Overall threat comments: The grasshopper is known from one subpopulation in an area with high urban housing development potential; ongoing recreational threats from long-term encampments/camping, garbage, and all-terrain vehicle use.

^a Impact – The degree to which a species is observed, inferred, or suspected to be directly or indirectly threatened in the area of interest. The impact of each stress is based on Severity and Scope rating and considers only present and future threats. Threat impact reflects a reduction of a species population or decline/degradation of the area of an ecosystem. The median rate of population reduction or area decline for each combination of scope and severity corresponds to the following classes of threat impact: very high (75% declines), high (40%), medium (15%), and low (3%). Unknown: used when impact cannot be determined (for example, if values for either scope or severity is unknown).

^b Scope – Proportion of the species that can reasonably be expected to be affected by the threat within 10 years. Usually measured as a proportion of the species’ population in the area of interest. (Pervasive = 71 to 100%; Large = 31 to 70%; Restricted = 11 to 30%; Small = 1 to 10%)

^c Severity – Within the scope, the level of damage to the species from the threat can reasonably be expected to be affected by the threat within a 10-year or three-generation timeframe. Usually measured as the degree of reduction of the species’ population (Extreme = 71 to 100%; Serious = 31 to 70%; Moderate = 11 to 30%; Slight = 1 to 10%).

^d Timing – High = continuing; Moderate = only in the future (could happen in the short term [< 10 years or 3 generations]) or now suspended (could come back in the short term); Low = only in the future (could happen in the long term) or now suspended (could come back in the long term); Insignificant/Negligible = only in the past and unlikely to return, or no direct effect but limiting.