550,000
540
Manx Shearwaters—particularly the larger, protected European colonies—have recently experienced moderate increases. A surplus of potential breeders from Europe may have contributed to range expansion and the establishment of North American colonies. Manx Shearwaters were found nesting in Massachusetts in 1973 (but not since) and nesting attempts are made annually at Matinicus Rock, Maine and more are being reported off the North Carolina coast. However, during the last several centuries, declines have occurred at some North Atlantic colonies. CBC data also show declines.
During the 1600s, Manx Shearwaters were harvested extensively in Europe; fledglings were extracted from burrows with iron hooks, killed, salted, and barreled for later boiling. Historically, the birds were also used for lighting-oil in lamps, ploughed into soil as fertilizer, and caught for use as lobster bait. Passage of the Wild Birds Protection Act of 1880 in Great Britain eliminated these practices; to a lesser extent, chicks are still hunted for food in Iceland, the Faeroes, and the Balearics.
Manx shearwaters in Scotland have been found to contain organochlorines from pesticides. Heavy metals recorded in shearwater tissue include zinc, cadmium, and mercury. Manx and related shearwaters are highly prone to crashing into structures after being blinded by bright lights. Some drown via entanglement in sardine fishery nets in the Bay of Biscay. On some larger offshore breeding islands in Europe, overgrazing and the resulting erosion has limited available habitat, restricting nesting to cliffs and other inaccessible sites. Introduced animals have been implicated in reducing or eliminating shearwater populations, including pigs in Bermuda, feral cats in Iceland, and rats on the Isle of Man. Burrows may collapse, and incubating shearwaters may desert, after nest inspections by researchers, particularly if frequent.
Due to intense competition for suitable nest sites, the availability of dry, smooth burrow sites is an important factor in shearwater population expansion and breeding success. Population reduction may arise from burrow competition. Shearwaters take readily to artificial burrows; wooden burrows have been used in Newfoundland colonies where natural burrows are in short supply.
Transplanting shearwater chicks to unoccupied islands, with subsequent broadcasting of calling shearwater recordings to attract returnees, has been attempted in Great Britain, with still uncertain results. Abandoning grazing has aided shearwater recovery at several colonies in Great Britain. Gull control has also resulted in lowered shearwater mortality. The shielding of strong white lights, coupled with their replacement by subdued colored lights, and intense rescue efforts for disoriented shearwaters, are effective strategies for mitigating disorientation.
Never let balloons drift off; shearwaters can become entangled in the strings, and marine mammals can mistake the balloons for food.
Join beach cleanups in your area. Properly discarding of debris, particularly plastic, will prevent shearwaters and other seabirds from eating it.
Make environmentally-friendly seafood choices, which helps protect the marine life that Manx Shearwaters and other seabirds depend upon. Learn more at
http://seafood.audubon.org/ or
http://www.mbayaq.org/cr/seafoodwatch.asp
Reduce your use of fossil fuels and don't discard used oil into city sewers or municipal water supplies. Transporting fuel inevitably results in oil spills, which can end up in the ocean where shearwaters rest and feed; if their feathers become oiled, the birds are no longer waterproof and cannot survive.
Cut up monofilament fishing line, which can entangle seabirds, prior to discarding it.
Find out about
actions you can take including Audubon programs and activities.
Learn more about international seabird conservation efforts at the
North American Bird Conservation Initiative, and the
North American Waterbird Initiative.
Learn about ocean conservation at
http://www.livingoceans.org/index.shtml
Learn more about this species and other birds through
these resources.
Kaufman, Kenn.
Lives of North American Birds. Houghton Mifflin Company, New York, 1996
Lee, D. S., and J. C. Haney. 1996. Manx Shearwater (Puffinus puffinus). In
The Birds of North America, No. 257 (A. Poole and F. Gill, Eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
Sibley, David Allen.
The Sibley Guide to Birds. Alfred A. Knopf, Inc., New York, 2000
