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Razorbill (Alca Torda)

Razorbill (Alca Torda)

STATE THREATENED

Razorbill (Alca torda)

Description In the northern hemisphere, ’s puffins, , and are the ecological equiva- lent of . Appropriately dressed in “formal attire,” these tuxedoed fly underwater, capture fish, and live in large colonies. Another relative, the extinct great , used to winter off the coast of Maine.

Razorbills are short (17 inches long), chunky Linda Welch with short, stubby . They are members of the auk family and are closely related to puffins, southern edge of their range. Razorbills nest on guillemots, and murres. The breeding adult rocky, isolated islands, although they occasionally is distinguished by a black back and head, white nest on mainland cliff faces or headlands if mam- belly, thick bill, and uptilted tail (when swimming). malian predators are absent. Islands must have The black bill is flat with a vertical white mark suitable nesting sites, which include ledges with midway along its length. A white line extends from crevices and boulder fields, and deep rock fissures. the eye to the bill. Winter plumage is similar; the Razorbills only nest on three islands in Maine: bill covering is shed, and the throat, cheeks, and ear Matinicus Rock, Freeman Rock, and Old Man coverts are white. Legs and feet are black. On Island. The largest colony in the Gulf of Maine is on breeding grounds, razorbills make a low guttural or Machias Seal Island on the Maine/New Brunswick croaking urrr sound. border. After breeding, razorbills stay out to sea along pack ice areas of the North Atlantic. In the Range and Habitat western Atlantic, razorbills winter at sea off Atlantic The razorbill is Canada south to . found in arctic and subarctic marine waters Life History and Ecology from Maine to north- Razorbills breed for the first time when they are ern Russia. There are 4-6 years of age. Immatures return annually to about 700,000 razor- breeding colonies, with the youngest birds arriving bills in the North later in the breeding period and staying the shortest Atlantic, and over 70 amount of time. As birds get older, each year they percent of the popula- arrive at the breeding colonies progressively earlier tion nests in . and spend more time at the colony prospecting for About 330 pairs nest in mates and nesting sites. Most return to breed at the

Range in Maine the Gulf of Maine, colony where they were born, and keep the same Known locations which is the extreme mate for several years. Razorbills return to breeding

• Maine’s Endangered and Threatened Wildlife ©2003 Maine Department of Inland Fisheries & Wildlife • colonies in Maine in February and early March, grams on Matinicus Rock and Machias Seal Island about three months before egg laying begins. benefit razorbills. Active programs are underway to During this period, they alternate time at the colony establish new colonies at Eastern Egg and Petit displaying and defending nest sites with time at sea Manan Islands. Razorbills were listed as threatened feeding. Nest sites are typically under rocks and in in Maine in 1997 because of their small population crevices. Egg laying occurs during May and June, size and limited distribution. All razorbill islands in and is closely related to sea surface temperature. A Maine are in conservation ownership and protected single egg is laid on bare rock, and is incubated by by Significant Wildlife Habitat provisions of the both adults for about 35 days. Natural Resource Protection Act. After hatching, the chick is closely brooded by the parents until it can regulate its own body tem- Recommendations: perature at about 9-10 days of age. When about 18 ✔ Protect nesting islands and adjacent days old, the partially grown and flightless chick waters from further development, especially human leaves the colony in the middle of the night to avoid dwellings, fishing piers, docks, and aquaculture predation. Primary and secondary feathers facilities. Review Essential Habitat maps and develop after the young has left the colony. The guidelines prior to development near roseate tern adult male accompanies its chick to sea, where it islands. Consult with a biologist from MDIFW and feeds the chick for several weeks. Adults feed the U.S. Fish and Wildlife Service to assist with primarily on fish, including , Atlantic planning. , Atlantic , and . Fall migration ✔ Municipalities should strive to prevent develop- begins in mid-September in Maine. Longevity may ment of seabird nesting islands and adjacent waters exceed 30 years. and identify these areas in comprehensive plans. Consider protecting a ¼ mile buffer around seabird Threats nesting islands. Historically, razorbills were more numerous, but ✔ Use voluntary agreements, conservation ease- not abundant, at the southern edge of their range. ments, conservation tax abatements and incentives, They declined from overharvest for food, feathers, and acquisition to protect important habitat for and eggs. In the last 50 years, expanding popula- threatened and endangered . tions of black-backed and herring became ✔ Stay off seabird nesting islands during the serious predators of razorbills, their chicks and eggs. nesting season (April 1 to August 15). If visitation is The presence of gulls inhibits razorbills from recolo- approved (e.g., commercial tours to a seabird nizing some former nesting areas. The availability of island), remain on designated paths and in blinds to food can affect breeding success. Incidental take in minimize disturbance. gill nets can be a serious problem in some areas. Oil ✔ Keep boat activity more than 660 feet from pollution and spills have the potential to kill large seabird nesting islands. If birds flush from the island, numbers of birds. Maine razorbill nesting islands are you’re too close. remote and rarely visited by humans, so human ✔ Keep all pets off islands. Do not introduce disturbance is not typically a concern. mammalian predators. ✔ Locate aquaculture facilities farther than ¼ mile Conservation and Management from seabird nesting islands. ✔ Historic data on razorbills in Maine are nonexist- Avoid overfishing and polluting nursery areas for ent. Hunting and egg collecting eliminated the herring, hake, and other fish stocks important as species from Maine islands by 1890. At some time food for seabirds. ✔ in the 1900s, they began to return to some former Do not use gill nets near seabird islands or nesting islands, and by the 1970s there were about known feeding areas. ✔ 25 pairs on two islands. About 180 pairs currently Do not dump oil, litter, or waste overboard. nest on three islands, and the population is believed Even small amounts of oil can kill birds. Seabirds to be slowly increasing. About 150 pairs nest on are often injured by eating plastic particles from Machias Seal Island. Unlike most other endangered trash that are mistaken for food. ✔ seabirds, razorbills still exist on unmanaged islands Avoid overboard discharge of fish waste or bait. (Old Man Island and Freeman Rock). These rocky Predatory gull populations have increased because enclaves are unsuitable for nesting gulls, thus provid- of this readily available supply of food. ing predator-free habitat for razorbills. Ongoing gull control and management pro-

• For more information: MDIFW Endangered Species Program • 207-941-4466 • www.mefishwildlife.com •