Brachyramphus brevirostris
| Kingdom |
Phylum |
Class |
Order |
Family |
| ANIMALIA |
CHORDATA |
AVES |
CHARADRIIFORMES |
ALCIDAE |
| Scientific Name: |
Brachyramphus brevirostris |
| Species Authority: |
(Vigors, 1829) |
Common Name/s:
| English |
– |
Kittlitz's Murrelet |
|
Assessment Information
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| Red List Category & Criteria: |
Critically Endangered
A4bcde
ver 3.1
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| Year Assessed: |
2010 |
| Assessor/s: |
BirdLife International |
| Reviewer/s: |
Calvert, R., Symes, A., Butchart, S. |
| Contributor/s: |
Kuletz, K., Day, R. |
Justification:
This poorly known alcid has recently suffered an extremely rapid population decline owing to a variety of threats, qualifying it as Critically Endangered. However, recent surveys suggest that the population may not be undergoing such a steep downward trend, and upon clarification the species may warrant downlisting in the near future.
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| History: |
| 2009 |
– |
Critically Endangered
|
| 2008 |
– |
Critically Endangered
|
| 2005 |
– |
Critically Endangered
|
| 2004 |
– |
Critically Endangered
|
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Geographic Range
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| Range Description: |
This species has a distribution that is geographically centred on the Bering Sea where it is rare and patchily distributed in both Russia and the USA. In Alaska (where c.70% of the total population occurs2) it is found from just east of Cape Lisburne south to the Aleutian Islands and east to LeConte Bay. In Russia it is limited to the eastern Chukotskiy Peninsula in the Chukchi Sea west to Cape Schmidt and south to Anadyr Gulf, as well as Shelikov Bay in the northern Sea of Okhotsk1. The Alaskan population is estimated to number 8,190-36,193 birds17, and surveys in much of the Alaskan range indicated that populations may have declined by >80-90% during the past 15 years5. In Prince William Sound the population declined by 84% between 1989 (6,436 birds) and 2000 (1,033 birds) following a possible longer term decline since 1972 when the population was estimated at 63,000 individuals 2,6. In the Malaspina Forelands, numbers declined by 38-75% in 1992-2002. In Glacier Bay, density estimates declined by 89.1% in 1991-2000, with c.2,200 birds estimated there in 1999-20002. Total abundance in Icy Bay, Alaska, was estimated to be 1,725-2,372 birds in 2002, suggesting a decline of 59% over a three-year period4. There are no trend data from other parts of the species's range, but anecdotal information suggests population declines are occurring in at least some of these other areas. The wintering distribution includes records from coastal Kamchatka, the Kuril Islands, Hokkaido (Japan) and the continental shelf of the northern Gulf of Alaska9, and birds are present year-round at Kodiak Island (Alaska)11.
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| Countries: |
Native:
Canada; Japan; Russian Federation; United States
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| Range Map: |
Click here to open the map viewer and explore range.
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Population
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| Population: |
The population in Alaska is currently estimated at 19,578 individuals (range of 8,190-36,193; USFWS 2009). Data from Russia is scarce, but 5,100 birds are estimated to occur along Kamchatka and the Chukotka Peninsula (USFWS 2009), hence the population is best placed in the band 20,000-40,000 individuals.
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| Population Trend: |
Decreasing
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Habitat and Ecology
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| Habitat and Ecology: |
It lays a single egg on the ground amongst unvegetated scree or on cliff faces, but one recently found nest on Kodiak Island, Alaska, was on exposed bedrock11. Breeding was thought to be restricted to sites at or near the tops of mountains in glaciated regions1, but twelve active nests were recently found on Agattu in the western Aleutians, indicating that the species can nest at high densities in areas far from glaciers11. Individuals do not breed until 2 - 4 years of age, and may not breed every year8. It generally forages in different water types to the closely related Marbled Murrelet, preferring but not exclusively feeding during the breeding season in turbid waters of glacial origin3. It feeds on fish and macro-zooplankton. During winter, recent work suggests that small groups are present in the Bering and Chukchi Sea in spring and autumn, but not in summer. Birds are almost always found in open leads of pack ice during early spring, but not in other times of the year, and birds are often found near Point Barrow in the autumn16.
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| Systems: |
Terrestrial; Marine |
| Major Threat(s): |
There have been strong links made between this species's decline and areas of glacial recession (possibly as a result of climate change)5,6,7. Other threats include habitat degradation and repeated disturbance of birds owing to recreational and commercial tour-boat traffic; mortality in gill-net fisheries (documented in Prince William Sound, Yakutat Bay, and near Kodiak Island16); mortality from petroleum contamination (7-15% of the Prince William Sound population died as result of the ExxonValdez oil spill); and a change in prey species abundance adversely affecting piscivorous fish10. Boat traffic in Glacier Bay was found to cause a 30-fold increase in flight behaviour, and nearshore densities of murrelets were temporarily suppressed by vessel passage, although this was not found to result in a persistent loss of foraging habitat14. In 2008 the US Government auctioned leases to drill for oil and gas in the Chukchi Sea off Alaska, raising the potential prospect of catastrophic oil spills at in an area where the species is known to breed if drilling is allowed to commence15. Near-zero productivity in 1996-1998 for unknown reasons may lead to further future declines8. Birds breeding in the western Aleutians have been found to have low reproductive success, with losses during the incubation period primarily due to avian predators locating unattended eggs, and chick mortality during the nestling period largely due to inclement weather13.
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Conservation Actions
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| Conservation Actions: |
Conservation Actions Underway
In the USA the species is a candidate (listing priority 2) under the Endangered Species Act, and is listed in the Russia Red Data Book7,16. Guidelines have been drawn up in the USA to avoid disturbance of nesting birds. From 2005 to 2009 in Icy Bay, Alaska, 340 birds have been banded, and 122 adults and four juveniles have been radio-tracked leading to the discovery of eight nests18. The Pacific Seabird Group established the Kittlitz's Murrelet Technical Committee in 2008 to, amongst other things, act as a technical authority on ecology, distribution and ecology of the species; indentify, encourage and facilitate research; address conservation problems, and; act as a liason between research and management16.
Conservation Actions Proposed
Monitor population and trends in Alaska and Russia. Assess the impact of gill-net fisheries. Develop innovative gill-net gear and fishing methods to reduce bycatch. Assess the impact of boat traffic on use of foraging areas. Reduce habitat degradation and human disturbance through private sector codes of conduct. Enforce legislation to reduce the chances of oil-spills and other pollution. Tackle the threat of global climate change through international agreements. Estimate reproductive performance and other important population parameters to determine the most important factors affecting population stability. Identify and protect important courtship and nesting habitats. Identify important non-breeding areas.
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