Black-footed albatross (Phoebastria nigripes) COSEWIC assessment and status report: chapter 11
Technical Summary
Phoebastria nigripes
Black-footed Albatross – Albatros à pieds noirs
Range of Occurrence in Canada:
Canadian territorial waters off British Columbia
Extent and Area Information
Extent of occurrence (EO) (km²)
- Approx 70,000 km²
- Area of Canadian territorial waters on Pacific Coast
Specify trend in EO
Stable
Are there extreme fluctuations in EO?
No
Area of occupancy (AO) (km²)
- Approx. 70,000 km² (ca. 22 km² on breeding colonies; BirdLife International 2004a)
- Area of Canadian territorial waters on Pacific Coast and total terrestrial area of breeding colonies (outside Canadian waters)
Specify trend in AO
Unknown
Are there extreme fluctuations in AO?
No, though there may be seasonal and annual distributional shifts within the EO, based on changing oceanographic conditions
Number of known or inferred current locations
Not applicable in Canadian waters; 12 established breeding locations worldwide (see Distribution section)
Specify trend in #
Not applicable in Canada; stable or increasing worldwide with four new breeding localities (see Distribution section)
Are there extreme fluctuations in number of locations?
No
Specify trend in area, extent or quality of habitat
Breeding habitat stable
Population Information
Generation time (average age of parents in the population)
- 17-20 years (Niel and Lebreton 2005, Lewison and Crowder 2003; NatureServe 2006);
- 18.67 years (following IUCN calculation; BirdLife International 2004a,b)
- See text for discussion of generation time estimates
Number of mature individuals
123,140 (see Table 1) Estimated number of breeding pairs × 2
Total population trend:
Unknown. Published sources: declining (See Population Sizes and Trends section)
% decline over the last/next 10 years or 3 generations.
- Laysan Island, 1992-2005, decline (p < 0.002);
- Midway Atoll, 1992-2005, no trend (p > 0.5; Fig. 11).
- Three of four largest colonies summed (French Frigate Shoals, Laysan Island, Midway Atoll), 1992-2005, no trend (p > 0.5; Fig. 13)
- Limited historical data precludes an analysis of % decline over 3 generations (ca. 60 years)
Are there extreme fluctuations in number of mature individuals?
No, though pronounced interannual fluctuation in number of adults returning to breed
Is the total population severely fragmented?
No – island colonies isolated, but genetic exchange possible
Specify trend in number of populations
Stable: although incipient Mexican colonies are geographically isolated, they will not be genetically isolated from NWHI population (see Distribution section) and are not considered a separate population for this report
Are there extreme fluctuations in number of populations?
No
List populations with number of mature individuals in each:
- Northwestern Hawaiian Islands – 118,240;
- Japan – 4,900 (see Table 1)
Threats (actual or imminent threats to populations or habitats)
Incidental mortality in longline and driftnet fisheries; mortality from oil spills; loss of breeding habitat from climate change and associated sea level changes; climate-change induced changes in marine productivity; habitat alteration and depredation by invasive species (plants, rabbits, cats, rats); pollution, including plastic ingestion and bioaccumulation of organochlorines; volcanic eruption at Torishima and Revillagigedo Is. (see Limiting Factors and Threats section).
Rescue Effect (immigration from an outside source)
Status of outside population(s)?
Not applicable
Is immigration known or possible?
Not applicable
Would immigrants be adapted to survive in Canada?
Not applicable
Is there sufficient habitat for immigrants in Canada?
Not applicable
Is rescue from outside populations likely?
Not applicable
Quantitative Analysis
Some models predict 60% decline in 3 generations, others predict stable population
See discussion of competing models. Also see Arata et al. (in review). Niel and Lebreton (2005) modelled the mortality level that would result in a population decline; estimates of fisheries bycatch mortality approximate this number.
Current Status
COSEWIC: Special Concern (2007)
IUCN: Endangered (A3bd)
Status and Reason for Designation
Status: Special Concern
Alpha-numeric code: not applicable
Reasons for Designation: This long-winged, long-lived (up to 40 years) seabird breeds on remote islands in the Hawaiian chain, but significant numbers feed off the coast of British Columbia each year, including adults making long foraging trips to feed their young. Black-footed Albatross numbers declined at one of the two major colonies in the 1990s, but the population seems generally stable. Many are caught as bycatch in longline fisheries; most suffer from ingestion of plastic and accumulate high levels of pollutants. The long-term effects of these threats are unclear.
Applicability of Criteria
Criterion A: (Declining Total Population): No significant declining trend.
Criterion B: (Small Distribution, and Decline or Fluctuation): No significant declining trend.
Criterion C: (Small Total Population Size and Decline): Population too large.
Criterion D: (Very Small Population or Restricted Distribution): Comes close to meeting restricted distribution category (22 km² area of 12 colonies).
Criterion E: (Quantitative Analysis): conflicting results; some predict 60% decline over 3 generations, others predict a more or less stable population.