Globally, seabirds are the most threatened species-groups of birds. Of the 328 species of seabirds currently known, 102 are threatened or endangered and five are thought to be extinct. However, seabirds respond well to small- to-mid-scale conservation actions, making them good candidates for conservation investment (see below).
In California alone, there are 22 seabirds on the Audubon Watchlist, just under a third of the total.
Major impacts and threats to seabirds
Introduced mammals and plants
Most seabirds breed in high densities on oceanic islands and have not evolved with predators. Introduced cats, rats, rabbits, and mice have devastated breeding colonies on islands around the world, eradicating seabird colonies. Invasive plants have made many areas inhospitable to nesting. Fortunately, when predators, herbivores and invasive plants are removed, seabirds can quickly re-colonize abandoned breeding islands.
Solution: remove introduced species and attract nesting birds.
U.S. Fish & Wildlife Service Common Murre Restoration Project:http://www.fws.gov/SFBAYREFUGES/MURRE/webcam.htm
Aleutian/Rat Island seabird restoration: http://www.seabirdrestoration.org/updates.html
Seabirds are attracted to fishing vessels and drown in hooks or on nets. An estimated 300,000 seabirds are killed each year, including 100,000 albatrosses. Due in large part to the many millions of fish hooks and nets in the ocean, 19/23 species of albatross are threatened with extinction.
Solution: Cheap, effective bycatch reduction gear such as weighted lines, bird-scaring “tori” lines, and dyed bait, which reduce seabird bycatch by up to 95%.
BirdLife International’s Save the Albatross Program:http://www.birdlife.org/action/campaigns/save_the_albatross/
Bottom trawlers destroy reefs and benthic habitats, and people and birds often target the same prey species: rockfish, anchovy, herring, squid, even tiny shrimp-like krill. Many fisheries are not managed with a precautionary approach that considers the needs of marine predators. The result may be hungry birds and chicks.
Habitat conversion and disturbance
Human habitation and use of coastal areas removes seabird breeding, foraging and resting habitats on islands and shorelines. In the California Current, most oceanic islands are part of national parks and wildlife refuges, and many have been restored for seabirds and marine mammals. However, many remain un-restored, and disturbance by fishing vessels, tourists, and shipping is chronic and increasing in many areas.
Clinate change is already affecting the California Current, by changing the timing and intensity of summer upwelling events. Other expected effects include ocean acidification, which will make it more difficult for most species shellfish to thrive, and increased dinoflagellate blooms, which are suspected to be taking place now. Overall, seabirds will be affected in different ways. Some species may do better, some worse. Currently any predictions are speculations, which is why it is critical to increase the amount of surveillance of trends in seabird populations over the long term.
Far out on the Pacific, between Hawaii and California, a huge patch of floating plastic grows in size each year. This trash kills millions of sea creatures each year, including sea turtles, seabirds and predatory fish.
Oil spills and organochlorine pollution continue to be a major threat for seabirds and the environments that support them.
How you can help, right now
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