ATLANTIC PUFFIN/RAZORBILL ASSESSMENT 4 November 1999 MAINE DEPARTMENT OF INLAND FISHERIES AND WILDLIFE WILDLIFE DIVISION WILDLIFE RESOURCE ASSESSMENT SECTION BIRD GROUP by MaryEllen R. Wickett Atlantic Puffin / Razorbill Assessment TABLE OF CONTENTS Page INTRODUCTION............................................................................................................. 3 NATURAL HISTORY....................................................................................................... 4 Description............................................................................................................ 4 Atlantic Puffin............................................................................................. 4 Razorbill..................................................................................................... 7 Distribution............................................................................................................ 8 Atlantic Puffin............................................................................................. 9 Razorbill..................................................................................................... 9 Migration............................................................................................................. 10 Feeding .............................................................................................................. 11 Atlantic Puffin........................................................................................... 11 Razorbill................................................................................................... 13 Breeding Biology ................................................................................................ 14 Atlantic Puffin........................................................................................... 14 Razorbill................................................................................................... 21 Survival and Longevity ....................................................................................... 25 MANAGEMENT ............................................................................................................ 27 Regulatory Authority ........................................................................................... 27 Past Goals and Objectives ................................................................................. 28 Past and Current Management........................................................................... 29 HABITAT ASSESSMENT.............................................................................................. 32 Past Habitat........................................................................................................ 33 Current Habitat ................................................................................................... 36 Habitat Projection ............................................................................................... 46 POPULATION ASSESSMENT...................................................................................... 47 Past Populations................................................................................................. 47 Current Population.............................................................................................. 48 Population Projections........................................................................................ 50 Limiting Factors .................................................................................................. 51 USE AND DEMAND ASSESSMENT ............................................................................ 54 SUMMARY AND CONCLUSIONS ................................................................................ 56 LITERATURE CITED .................................................................................................... 58 2 Atlantic Puffin / Razorbill Assessment INTRODUCTION Since 1968, the Maine Department of Inland Fisheries and Wildlife (MDIFW) has aggressively pursued development and refinement of wildlife species assessments and implementation of cost-effective comprehensive programs that support selected goals and objectives for the next 15 years. Assessments are based upon available information and the judgments of professional wildlife biologists responsible for individual species or groups of species. Precise data may not always be available or are too limited for meaningful statistical analysis; however, many trends and indications are sometimes clear and deserve management consideration. The assessment has been organized to group information in a user-meaningful way. The Natural History section discusses biological characteristics of the species that are important to its management. The Management section contains history of regulations and regulatory authority, past management, past goals and objectives, and current management. The Habitat and Population sections address historic, current, and projected conditions for the species. The Use and Demand section addresses past, current, and projected use and demand of the species and its habitat. A Summary and Conclusions sections summarizes the major points of the assessment. 3 Atlantic Puffin / Razorbill Assessment NATURAL HISTORY Description Auks (Alcidae) are the ecological counterparts of penguins in the Northern Hemisphere (Cowger 1976). Five alcid species breed in the North Atlantic below the Arctic Ocean; only the Atlantic Puffin (Fratercula arctica), Razorbill (Alca torda), and Black Guillemot (Cepphus grylle) breed as far south as Maine (Cowger 1976, Boag and Alexander 1986). Auks are a highly specialized group of seabirds, being more adapted for underwater swimming than for long-distance flying (Evans and Nettleship 1985). Their wings are short and reduced in area, improving underwater propulsion. Flight is direct and rapid but not maneuverable; wing-loading is high, and take-off is difficult (Bédard 1985). Bill shape varies by alcid species, reflecting diet and feeding method (Freethy 1987). Atlantic Puffin--Atlantic Puffins (Fig. 1) have a short, thick neck and short, blunt tail (Boag and Alexander 1986). They have large, webbed feet, with short, sturdy legs (tarsus: 26 mm) set far back on the body producing an upright stance (Knight 1908, Boag and Alexander 1986). Males are slightly heavier (429.0- 524.0 g, x=479.0 g) than females (386.0-511.0 g, x=445.5 g) (Johnsgard 1987). Beaks are longer and deeper for Fig. 1. Atlantic Puffin (photo from http://search.corbis.com/ x av.asp?id+AF001957, males than females (culmen: M=45.0-53.5 mm, =49.8 3305306.jpg. 30 Sep 99) mm; F=44.0-51.0 mm, x=48.0 mm) (Johnsgard 1987), 4 Atlantic Puffin / Razorbill Assessment giving males 10% more bill area (Harris 1984). Wingspan is 45-63 cm (Freethy 1987), with wing length ranging 157.0-168.0 mm (Johnsgard 1987). Atlantic Puffins are shorter (26-30 cm) than Razorbills (35-40 cm) (Cowger 1976, Boag and Alexander 1986, Freethy 1987). During the summer breeding period, adult male and female puffins are similarly plumaged with black above, white underparts, and pale gray cheek patches (Johnsgard 1987). The beak is compressed laterally and triangular in profile. Approximately one- half of the bill nearest the tip is bright red-orange, with a slate blue-grey basal section. These 2 areas are separated by a pale yellow ridge. The upper mandible is joined to the feathers by a pale yellow fleshy strip. There is a bright yellow wrinkled rosette where the upper and lower mandibles join (Boag and Alexander 1986). The yellowish grooves in the red area of the bill can be used to determine age and maturity, with lines increasing in length and number as the bird matures. At maturity (4-5 years old), adults have 2 complete grooves (Freethy 1987). Inside the mouth and the tongue are yellow (Johnsgard 1987). The puffin's iris is a dark brown, surrounded by a red orbital ring. Above and below the eye are 2 horny blue-grey patches; the upper patch is triangular, the lower patch more rectangular (Boag and Alexander 1986, Johnsgard 1987). Legs and feet are bright orange. The sharp, black claws on the feet are up to 1 cm long (Boag and Alexander 1986, Freethy 1987). Soon after the breeding season is completed, the outer sheaths of the bill and horny ornaments above and below the eye are shed. The puffin bill becomes smaller and loses its bright color. The blue-grey base of the bill is shed, the red fades to dull yellow, and the yellow wattle at the hinge of the bill withers away. The red eye ring 5 Atlantic Puffin / Razorbill Assessment disappears (Freethy 1987, Johnsgard 1987). Head and neck feathers are molted, the white face patch and abdomen become grey (Harris 1984, Freethy 1987). Legs turn to a dull yellow color (Bédard 1985). Puffins have a synchronous primary molt and flightless period. The wing molt occurs at sea making timing difficult to determine. The molt likely occurs in late winter; adults have complete replacement of primaries prior to returning to breeding colonies in early spring (Harris 1984). Juvenile puffins look similar to winter plumaged adults; however, the bill is smaller, duller in color, and lacking grooves or ridges (Johnsgard 1987), and the dark area in front of the eye is more extensive and blacker (Harris 1984). The bill reaches full length by the end of the first winter, but continues to increase in area (approximately 25% increase) by becoming deeper and to a lesser extent by an increase in the curvature