Killer whales (Orcinus orca) recovery strategy: chapter 3

3. Critical habitat

“Critical habitatFootnote 6” is defined under the Species at Risk Act (SARA) as “the habitat that is necessary for the survival or recovery of a listed wildlife species that is identified as the species’ critical habitat in the recovery strategy or in an action plan for the species” (SARA s.2 (1)). Under SARA, defining critical habitat for killer whales to the extent possible is a legal requirement (SARA s.41 (1) (c)). Once critical habitat is identified by the Minister, no person shall destroy any part of the critical habitat (SARA S.58 (1) and the minister must describe in the public registry how the critical habitat is legally protected (SARA S.58 (5))

Defining critical habitat for any species is challenging, but especially so for mobile marine animals such as killer whales. Resident killer whales travel over large geographical distances and members of the northern and the southern resident communities may be spread over hundreds of kilometres at any given point in time. As well, much of what we know about killer whales comes from the very short period of time they spend at the surface where we can see them, and the ways in which they travel and utilize their three dimensional underwater habitat are not at all well understood. The underwater vocalizations of resident killer whales provide some insight into their behavioural state, but tell us little about how geographic features of the environment are used. According to the best knowledge at this time, the habitat most important to killer whales in the summer and fall are channels, shorelines, or other topographic or oceanographic features that concentrate their migratory prey, salmon.

There is little evidence to suggest that killer whales require or are limited by specific physical features of their environment, other than features that make prey available to them. Indeed, as top level predators, killer whales in general are not known to require refugia, and they inhabit a wide range of both nearshore and pelagic habitats worldwide and tolerate a wide range of temperature, salinity and turbidity levels. The presence of resident killer whales is closely associated with the presence of salmon (Heimlich-Boran 1988, Felleman et al. 1991, Osborne 1999, Nichol and Shackleton 1996, Ford et al. 1998), and it is this overwhelming feature of the environment that affects their distribution, although knowledge is limited temporally to summer and fall months. For the rest of the year there is much less information available on their diet or distribution and movement patterns. Clearly, determining whether there are additional habitats, that the whales utilize during the winter and spring, which are critical for recovery, must be a specific objective for the action plan. Such criteria will need to take into account the likelihood that changes in the relative strength of major salmon stocks may cause corresponding shifts in the geographic location of critical habitat for resident killer whales.


3.1 Identification of the species' critical habitat

Two seasonal concentration areas for resident killer whales off northeastern and southeastern Vancouver Island have been well documented and meet the requirements for designation as critical habitat under SARA. Critical habitat (Figures figure4 and figure5) is described by coordinates for each population (see Appendix B), and includes the identified attributes of the availability of the preferred prey (specifically Chinook and Chum salmon) and the lack of acoustic disturbance or chemical contamination which would prevent the area from being used by the species for foraging, socialising, mating, resting, and in the case of the northern residents, beach rubbing."

Both of these areas are characterized by narrow channels with strong currents, and appear to be geographical 'funnels' that tend to concentrate migrating salmon bound for the Fraser River, which has the largest salmon production in the region (Northcote and Larkin 1989), and other smaller river systems flowing into the Strait of Georgia and Puget Sound. Rational for the designation of critical habitat and a general description of the habitat and its features is presented in Section section3.1.1 and section3.1.2 for northern and southern residents respectively.

There are likely other areas that are important for killer whales at various times, but these have not yet been studied in sufficient detail to be identified with confidence. Measures to identify and effectively protect other critical habitat areas will be described in the action plan that follows this recovery strategy.


3.1.1 Southern residents

The critical habitat for southern resident killer whales includes the transboundary areas of southern British Columbia and Washington State. These include Haro Strait and Boundary Pass and adjoining areas in the Strait of Georgia and the Strait of Juan de Fuca, as depicted in Figure 4 (see Appendix B for description of the area designated). This area represents a very important concentration area for southern resident killer whales. Analyses of existing data on coast-wide occurrence patterns of southern resident killer whales has been completed by the US, National Oceanic and Atmospheric Administration (NOAA) as part of the Endangered Species Act (ESA) designation of critical habitat in collaboration with Fisheries and Oceans Canada (DFO) (National Marine Fisheries Service (NMFS), 2006). This assessment provides quantitative documentation of the importance of these transboundary areas to these animals and forms, along with previously published information, the basis for the critical habitat identification. The following provides a general summary of the rationale for the identification and the important aspects of the habitat for southern resident killer whales.

The occurrence of southern residents in this area is strongly correlated with the timing of salmon migration through these waters (Heimlich-Boran 1988, Felleman et al. 1991, Osborne 1999). Within this area, locations that are particularly important for foraging are the nearshore waters along the west and southwest sides of San Juan Island, the southern tip of Vancouver Island, Swanson Channel off North Pender Island, and off the mouth of the Fraser River (Heimlich-Boran 1988, Hoelzel 1993, Ford et al. 2000; unpublished data Centre for Whale Research (CWR) and Cetacean Research Program-Fisheries and Oceans Canada (CRP-DFO).

Figure 4: Critical Habitat for Southern Resident Killer Whales. The hatched area in US waters shows the approximate areas designated as southern resident critical habitat under the US Endangered Species Act (ESA).

Critical habitat for southern resident killer whales. The hatched area in US waters shows the approximate areas designated as southern resident critical habitat under the US Endangered Species Act (ESA).

The critical habitat area is utilized regularly by all three southern resident pods during June through October, in most years (Osborne 1999, Wiles 2004). J pod appears to be present in the area throughout much of the remainder of the year, but two southern resident pods, K and L, are typically absent during December through April. This critical habitat is clearly of great importance to the entire southern resident community as a foraging range during the period of salmon migration, and thus meets the definition of critical habitat as described in the Species at Risk Act.

Much of the area that qualifies as critical habitat for southern resident killer whales falls within US jurisdiction, and thus the identification of critical habitat under SARA only applies to the portion of the area that is within Canadian waters (Figure 4). In November 2005, the United States listed southern resident killer whales as endangered under the Endangered Species Act (ESA),(NMFS 2005a). As a result 6630 square km of US inland waters of Washington State and the Strait of Juan de Fuca were designated as critical habitat under the ESA in November 2006 (see Figure 4), (NMFS, 2006b).


3.1.2 Northern residents

The critical habitat for northern resident killer whales includes the waters of Johnstone Strait and southeastern Queen Charlotte Strait, and the channels connecting these straits as depicted in Figure 5 (see Appendix B for legal description of the area designated). This area represents a very important concentration area for northern resident whales. Analyses of existing data on coast-wide occurrence patterns of northern resident killer whales has been completed (Ford, 2006) which provides quantitative documentation of the importance of Johnstone Strait to these animals and forms, along with previously published information, the basis for the critical habitat designation. Hereafter, the area designated as critical habitat is referred to as the 'Johnstone Strait critical habitat", and has long been the focus of research and whale watching activity involving the northern resident community (Johnstone Strait Killer Whale Committee (JSKWC) 1991). The following provides a general summary of the rationale for identification and the important aspects of the habitat for northern resident killer whales.

Northern residents frequent the area on most days during July through October, with peak numbers generally in mid-July to mid-September (JSKWC 1991, Nichol and Shackleton 1996). Whales become more sporadic in the area during November, and are scarce, but nevertheless occasionally seen, from December through May. Although all northern resident pods have been identified in the area, it is used most frequently by only part of the community, particularly groups belonging to A Clan (Ford 1984, Nichol and Shackleton 1996). Members of G Clan tend to be seen in the area more often in September and October than during summer in some years (Nichol and Shackleton 1996, unpublished data CRP–DFO). Northern resident killer whales in the Johnstone Strait area spend the majority of time foraging for salmon, primarily chinook, during July-September and chum in October (Ford 1989, Ford et al. 1998, unpublished data CRP-DFO). Other activities undertaken in the area include resting, socializing, and beach rubbing (Ford 1989, Ford et al. 2000).

Figure 5: The critical habitat for northern resident killer whales in summer and fall in British Columbia

The critical habitat for northern resident killer whales in summer and fall in British Columbia

Beach rubbing appears to be an important activity for northern resident killer whales. Ninety percent of whales in Johnstone Strait visit the rubbing beaches, and spend about 10% of their time there (Briggs 1991). During this time they are very sensitive to disturbance. In recognition of the importance of this habitat to killer whales, the province of British Columbia in 1982 established the Robson Bight–Michael Bigg Ecological Reserve to protect a portion of western Johnstone Strait and the foreshore near Robson Bight, where the rubbing beaches are located (Figure 5). However, in response to growing concerns about the impacts of human activities in and around Robson Bight, in 1990 the British Columbia and Canadian governments jointly appointed the Johnstone Strait Killer Whale Committee to develop management recommendations to ensure the conservation and protection of killer whales (JSKWC 1991, 1992). One of the key recommendations of the Committee called for the establishment of a Special Management Zone to encompass a larger marine area than the existing Ecological Reserve, and establish a seasonal patrol vessel program to monitor whale-oriented vessel activity and mitigate potential disturbance. The area identified as critical habitat encompasses the area recommended as a Special Management Zone.

The Special Management Zone includes the primary foraging areas for killer whales utilizing the Johnstone Strait area, as well as at least six beaches used to various degrees by these whales for rubbing, and is included within the shaded area in Figure 5. Given the importance of this area to a significant component of the northern resident community for a major portion of the salmon feeding season, and the traditional use of rubbing beaches located there, this area is designated as critical habitat as defined in the Species at Risk Act.

There may be additional areas that will qualify as critical habitat for northern residents during other parts of the year, and for northern resident groups that infrequently utilize the Johnstone Strait area during summer and fall, but there is insufficient information to characterize them at present. Analyses of existing data on coast-wide occurrence patterns of northern resident killer whales outside the designated areas are currently underway, which will identify additional candidate areas for consideration as critical habitat (Ford 2006). These areas might include portions of Dixon Entrance, Caamano Sound, Whale Channel, and the channels surrounding King Island on the central British Columbia (BC) mainland coast. Northern resident whales frequent all these locations in at least some years, especially during May to early July (Nichol and Shackleton 1996, unpublished data CRP-DFO). Several rubbing beaches have also been identified in other locations on northern Vancouver Island and the mainland coast, and might also warrant protection as critical habitats because of the importance of this behavioural tradition to the cultural diversity of resident populations.


3.2 Examples of activities likely to result in destruction of critical habitat

Many of the threats that face resident killer whales also affect their habitat, and this is of particular concern for the critical habitat. The threats to critical habitat are briefly listed here, but the reader is referred to Section 2.2 for a more thorough discussion on threats identified below. As previously mentioned, it is important to recognize that the definition and identification of critical habitat for resident killer whales is complex. There are many gaps in our understanding of critical habitat, and this will be a focus for research in the action plan.


3.2.1 Geophysical disturbance

A key physical feature of both the northern and southern resident killer whale's critical habitat is that these areas by virtue of their underwater topography funnel salmon into areas where they concentrate before spawning. Thus, any large scale physical disturbance, such as an earthquake, could significantly alter the channelling of salmon and could be considered a serious threat. However, such catastrophic events are not predictable and have a low probability of occurrence. Industrial activities such as construction, drilling, pile driving, pipe-laying and dredging are the most likely sources of critical habitat destruction. Fisheries using nets that drag along the bottom (accidentally or intentionally) also damage habitat. Vessel anchors damage the seabed and may serve to alter a rubbing beach or cause displacement. Physical structures such as wharves and net pens for aquaculture may displace killer whales. Both the placement of individual structures and the cumulative effect of multiple structures should be assessed against the needs of killer whales in critical habitat.

A key feature of the northern resident killer whale critical habitat is the presence of several rubbing beaches. Any destruction of rubbing beaches, or disturbance of the animals while in these areas should be considered a threat. Rubbing beaches may also be vulnerable to disturbance through flooding and landslides in areas adjacent to the beach.

Acoustic degradation

There is growing awareness that the underwater acoustic environment is extremely important to cetaceans (International Union for Conservation of Nature (IUCN) 2004, International Whaling Commission (IWC) 2004) and it is important that the threat of a degraded underwater acoustic environment be managed in critical habitat, in order that killer whales can maintain communication, and detect and capture prey while in the area. There are many threats to the acoustical integrity of critical habitat, and these are discussed in detail in Section 2.2.3. Underwater Noise. These include seismic surveys, military and commercial sonars, vessel noise, construction and dredging.


3.2.2 Chemical and biological contamination

The degradation of water quality due to environmental contaminants poses a particularly serious threat to killer whales, their prey and their habitat. These contaminants and their sources are discussed in Section 2.2.1. While many contaminants are airborne and dispersed throughout the coastal waters of British Columbia, the waters surrounding the lower mainland and Vancouver Island are particularly at risk due to their proximity to human settlement. This includes the risks to habitat associated with the introduction of exotic species. Urban land use represents a significant concern for the health of coastal ecosystems (Grant and Ross 2002) and a growing population makes this situation unlikely to improve. By 2020 the Canadian portion of this area is predicted to have a population of over 3.8 million (BC Statistics 2004), and the State of Washington, which borders this area is projected to have over 7.7 million people (Office of Financial Management, State of Washington (OFM) 2004).

The threat of a spill of oil or other toxic material within the areas of critical habitat pose not only an immediate and acute risk to the health of resident populations (see Section 2.2.4), but have the potential to make critical habitat areas un-inhabitable for an extended period of time.


3.2.3 Diminished prey availability

As the presence of salmon is key to the presence of killer whales in the critical habitat (Heimlich-Boran 1988, Nichol 1990, Nichol and Shackleton 1996, Osborne 1999), significant reduction to the quantity, quality and availability of salmon within critical habitat are a threat to its very function.

Prey must be physically accessible to resident killer whales in critical habitat, yet killer whales and fishing vessels targeting the same prey compete with each other for space, particularly in fishing hotspots. The presence of fishing vessels also alters fish behaviour (Mitson and Knudsen 2003) potentially making them less accessible to killer whales, although this is an area for further research.


3.3 Schedule of studies to identify critical habitat

While it is clear that protection of the habitat that serves as the primary foraging grounds for these populations during a portion of the year, through designation as critical habitat, is necessary at this time, there may be additional areas that will qualify as critical habitats for both resident populations during other parts of the year, and for northern resident groups that infrequently utilize the Johnstone Strait area during summer and fall. However, there is insufficient information to characterize these areas at present. The following table identifies these studies that are necessary to identify any additional areas for critical habitat designation.

 

Table 3: Schedule of studies to identify additional areas of critical habitat and its threats
Study Status
Year-round comprehensive surveys to identify areas of occupancy Underway
Identify key feeding areas throughout the year to determine whether they should be proposed as additional critical habitat Underway
Identify activities other than foraging that may be important functions of critical habitat Proposed
Identify sources of acoustic disturbance that may negatively impact or affect access to critical habitat Proposed
Identify sources of physical disturbance that may negatively impact or affect access to critical habitat Underway
Identify sources of biological and chemical contaminants that may negatively impact critical habitat Underway
Identify factors that may negatively affect an adequate and accessible supply of prey in areas of critical habitat Underway (due to salmon initiatives)


3.4 Mechanisms for the protection of critical habitat

A Protection Order, pursuant to subsection 58 (4) of the Species at Risk Act, has been issued to protect resident killer whale critical habitat.

In addition to the Protection Order, there are various mechanisms that will aid in the protection of resident killer whale critical habitat, including legislative tools such as acts, regulations, government policy and programs, as well as best practices, education and stewardship programs (see Table 4) that, given the current understanding of the nature and extent of the identified threats to critical habitat can provide additional protection. As the critical habitat for southern resident killer whales borders the waters of Washington State, where additional Critical Habitat exists, it is important that transboundary cooperation in protecting habitat is fostered. The following provides a summary of the applicability of the mechanisms outlined.

Within Canada, the Fisheries Act provides for the protection of habitat from physical alteration and the introduction of deleterious substances. The Marine Mammal Regulations (MMR, Section 7) of the Fisheries Act prohibit the disturbance of marine mammals; this includes activities such as the emission of high energy sounds (seismic surveys, low-mid frequency sonars) or sounds associated with various industrial activities. Garrett and Ross (In press) provide a thorough summary of the existing legislation and regulations regarding contaminants into the marine environment. Proactive efforts, to ensure that activities are assessed and controls and/or mitigative measures are implemented, are vital to the protection of the critical habitat identified for killer whales. Screening activities, such as those required under the Canadian Environmental Assessment Act (CEAA) and Integrated Management (IM) as described by the Oceans Act (OA) are essential mechanisms for protecting critical habitat. Monitoring and enforcement of all regulations is essential and complements the legislation and regulations listed above to ensure compliance.

Measures to manage threats to the foraging function of the critical habitat, primarily for salmon, can be accomplished through management activities under the Fisheries Act, directed by annual Integrated Fisheries Management Plans (IFMPs). A comprehensive approach to the management of salmon stocks that explicitly accounts for the dietary needs of killer whales should be evaluated and considered as one approach to protecting food resources.

Non-government education and stewardship programs (such as the Green Boater Program and Toxic Smart) will complement government programs and engage Canadians to take action at an individual level to protect critical habitat. In areas where critical habitat falls within a reserve or any other lands that are set apart for the use and benefits of a band under the Indian Act, the Species at Risk Act (SARA) states in Sections 58(7), 59(5) that the band must be consulted before the prohibition on the destruction of critical habitat is triggered or regulations are made to protect critical habitat on federal lands.

The following table summarizes the most understood potential threats to the critical habitat, along with a description of measures to protect it currently in place, and recommends additional measures that may be needed for the explicit protection of resident killer whale critical habitat, based on the current understanding of critical habitat and the associated threats. It is anticipated that the additional measures recommended will be evaluated in greater detail and articulated within the action plan for these populations. In addition, as a greater understanding develops of the important features of the habitat necessary to ensure the survival of these populations and the threats to this habitat, the mechanisms and measures needed to protect it will require revision.

 

Table 4: In addition to the Protection Order, current and recommended measures for the protection of critical habitat are listed
Threat Current Mechanisms Recommended Additional Measures
Geophysical Disturbance Fisheries Act and the

Canadian Environmental Assessment Act (CEAA) screening

Integrated management (IM) planning in northern resident critical habitat
Ensure all habitat alterations and marine use planning incorporate assessment of killer whale critical habitat

Consider IM planning for southern resident critical habitat

Apply precautionary approach in areas where critical habitat have not yet been identified
Geophysical Disturbance at Rubbing Beaches HPR

CEAA screening

BC Parks Ecological Reserve & Monitoring program (Robson Bight)

Remote surveillance technology (e.g. Orcalab)
Prohibit habitat alteration at rubbing beaches

Establish Marine Protected Areas (Oceans Act) at Robson Bight

Fisheries management actions (Fisheries Act) within rubbing beach areas

Evaluate need for protection at other rubbing beaches

Ensure all habitat alterations and marine use planning (e.g. fishing) incorporates assessment of rubbing beaches.
Acoustic degradation - seismic CEAA screening for some seismic programs and mitigation required

Non-CEAA seismic programs reviewed regionally

Marine Mammal Regulations (MMR) on disturbance
Evaluate recently developed draft standards for mitigation of seismic exploration

Apply precautionary approach in areas where critical habitat has not yet been identified

Amend MMR to provide for licensing (control) of disturbance activities

Require screening and authorization for all seismic activities

Encourage trans-boundary cooperation in mitigation measures
Acoustic Degradation- Sonar Protocols for military sonar use

MMR regulations on disturbance
Review existing military sonar use and protocols to ensure adequacy, revise as necessary

Amend MMR to provide for licensing (control) of disturbance activities

Encourage trans-boundary cooperation in mitigation measures

Apply precautionary approach in areas where critical habitat has not yet been identified
Acoustic degradation – industrial activity MMR disturbance regulations

DFO policy prohibits use of acoustic harassment devices
Consider and limit, as necessary, acoustic alteration from construction/development projects

Amend MMR to provide for licensing (control) of disturbance activities
Chemical & Biological Contaminants in Canadian watersFootnote a Stockholm Convention on Persistent Organic Pollutants (POPs)

GeorgiaBasin Action Plan (Environment Canada)

Non-Governmental Organization (NGO) environmental education programs (e.g. Green Boater Program, Toxic Smart etc.)

BC Environmental Management Act

Canadian Environmental Protection Act (CEPA) and Fisheries Act

Industry initiatives (e.g. Clean Print BC)

Integrated Pest Management Act (Integrated Pest Management Act (IPMA), Health Canada)

Canada-Wide Standards of Canadian Council of Ministers of the Environment

Fertilizers Act
Better identification and understanding of key contaminants and their sources

Increased enforcement of existing regulations

Increased funding for education at the individual, municipal and sector level

Evaluate and strengthen BC Environmental Management Act

Evaluate and strengthen the Canadian Environmental Protection Act

Continue to upgrade water treatment plants

Evaluate and strengthen the Integrated Pest Management Act, Fertilizers Act
Biological and Chemical Contaminants in US waters Numerous acts to protect critical habitat from contamination are listed in Garrett and Ross (In Press) Strengthen transboundary cooperation in reducing contaminants

Detailed recommendations in EVS (2003) including actions
Oil & Toxic Chemical Spills HPR regulations for deleterious substances

Canadian/ US spill response plan (CANUSPAC) in southern transboundary waters

CANUSDIX joint response plan in northern transboundary waters (Dixon Entrance)

BC Marine Oil Spill Contingency Plan 1992 (OSRIS)

Federal Marine Spills Contingency Plan

Regional Environmental Emergencies Team (REET)

Washington State Department of Ecology
Develop and incorporate into existing oil spill response plans measures specific to killer whales
Presence & Availability of Salmon Integrated Salmon Management Plan (Fisheries Act (FA) authority) provides for conservation of salmon

Regulations under the Fisheries Act to manage harvest activities
Evaluate resident killer whale prey and ensure that management plans incorporate adequate supply of prey for resident killer whales, even in changing climate scenarios

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