Tools and Technology Article Development and Validation of a Wing Key to Improve Harvest Management of Alcids in the Northwest Atlantic SABINA I. WILHELM, 1 Canadian Wildlife Service, Environment Canada, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada SCOTT G. GILLILAND, Canadian Wildlife Service, Environment Canada, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada GREGORY J. ROBERTSON, Wildlife and Landscape Science Directorate, Environment Canada, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada PIERRE C. RYAN, Canadian Wildlife Service, Environment Canada, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada RICHARD D. ELLIOT, Wildlife and Landscape Science Directorate, Environment Canada, 17 Waterfowl Lane, Post Office Box 6227, Sackville, NB E4L 1G6, Canada ABSTRACT Murres (thick-billed [Uria lomvia] and common [U. aalge]) are legally hunted along the coast of Newfoundland and Labrador, Canada. Razorbills (Alca torda) are also incidentally taken. Only irregular estimates of the total murre harvest are available, so a tool to derive estimates of age- and species-specific harvest is required to effectively monitor the hunt and manage a sustainable harvest. We collected 293 murre and razorbill wings from hunters between 1999–2004, with the goal of identifying wing characteristics that could be used to discriminate age and species. We found that murres and razorbills could be reliably aged (first-yr vs. older) on the basis of molt limits of greater wing coverts. Using a discriminant function (DF) incorporating length of the first primary and second secondary feather, we classified 95–96% of common murres and 99–100% of thick-billed murres correctly to species. First-year thick-billed and common murres also differed in number of pale secondary coverts (median ¼ 12 and 3, respectively), providing another species-specific trait. We developed a key to age and assign species based on these results. We assessed applicability and accuracy of the wing-key with novice observers, who differentiated between murre and razorbill wings using feather-pattern coloration with high accuracy (95 6 9%) and were able to differentiate between the 2 murres species using 3 techniques: visual assessment of wing shape (83 6 14% accuracy), the DF (94 6 6%), and number of worn secondary coverts for first-year birds only (83 6 5%). Experience increased success rates of aging and species classification using wing shape and number of worn secondary coverts but not using the DF. Despite differences in measurement accuracy and repeatability among observers, the DF proved to be robust. Our results will facilitate implementation of a species composition survey for the murre hunt and will improve identification rates of carcasses found during beached bird surveys in the Northwest Atlantic, aiding in monitoring of alcid populations vulnerable to anthropogenic activities. ( JOURNAL OF WILDLIFE MANAGEMENT 72(4):1026–1034; 2008) DOI: 10.2193/2007-232 KEY WORDS aging, Alca torda, alcid, harvest management tool, murre, Newfoundland, razorbill, species classification, Uria species, wing key. Each winter, 200,000 to 300,000 murres (Uria spp.) are legally hunted off the coasts of Newfoundland and Labrador, Canada (Chardine et al. 1999). Traditionally, Newfoundlanders harvested a variety of seabirds but lost this privilege after joining Canada in 1949 when provisions of the Migratory Birds Convention Act (MBCA) were implemented. Under the MBCA, all alcid species, including murres, are defined as migratory nongame birds, and therefore nonaboriginals may not harvest these birds at any time of year. However, rural Newfoundlanders relied heavily on murres for fresh meat during winter. Therefore, the federal government established a special regulation in 1956 allowing residents of Newfoundland and Labrador to legally harvest murres in autumn and winter (reviewed in Elliot 1991). Because murres were technically nongame birds, MBCA regulations enabling management of migra- tory game bird harvests did not apply. It became apparent, however, that thick-billed murre (Uria lomvia) harvest levels were unsustainable (300,000–700,000 killed annually be- tween 1977 and 1988; Elliot et al. 1991). Consequently, an amendment to the MBCA was signed in 1995, allowing regulation of the Newfoundland and Labrador murre harvest through bag limits and season length restrictions. However, it is only since 1999, following further amend- ments to the MBCA (Parksville Protocol) that hunters are required to purchase the Migratory Game Bird Hunting Permit to hunt murres. Effective management of the murre hunt requires reliable information on harvest. In Canada, Migratory Game Bird harvest levels are monitored annually using 2 cooperatively administered surveys. The National Harvest Survey (NHS) estimates total number of birds taken, and the Species Composition Survey (SCS) provides information on the age, sex, and species composition of the harvest. Since 2001, total murre harvest has been estimated irregularly through the regional Murre Harvest Survey, modeled after the NHS. However, current harvest estimates do not provide in- formation regarding age, sex, or species composition of the hunt because techniques are lacking to allow such information to be retrieved from body parts that are easily shipped (e.g., wing or tail feathers). A comprehensive study conducted during the 1980s examining age and species composition of the murre hunt revealed that thick-billed murres comprised about 95% of the total annual harvest, with 53% of these being first-year birds (Elliot 1991). The remaining 5% of the harvest consisted of common murres (U. aalge; Elliot 1991). Common murres are primarily taken on the south coast of insular Newfoundland or early in the hunt during their southward migration to their wintering grounds (Gaston et 1 E-mail: sabina.wilhelm@ec.gc.ca 1026 The Journal of Wildlife Management  72(4)