Noosing Adult for Banding

Geoffrey G. Hogan Department of Biological Sciences Brock University St. Catharine's, Ontario L2S 3A1

oosingis a wellknown means of capturingbirds for Between 1976 and 1979 there were 6 Great banding and marking, althoughnoose designs and colonieson Prince Edward Island containinga maximum capturetechniques vary widely (seeMcNicholl 1983).The 738 nests (Hogan 1979). By 1983 there were 8 colonies noosingtechnique reported here was usedto captureadult containing 1324 nests (Hogan 1983). All coloniesare on Great Cormorants( carbo) at a breedingcol- sandstoneseacliffs ranging in height from 6 to 33 m. ony on Prince Edward Island, during a studyof breeding parametersof this speciesand Double-crestedCormorants Between 1974 and 1978 I banded 538 Great Cormorant (P.auritus) from 1976 to 1979 (Hogan 1979).According to nestlingsat the breeding colony on Durell Point, on the Lewis (1929),Double-crested Cormorants were captured east coastof the island. The majority of nests (approx. for food by Indians with nooses,and adult PelagicCor- 95%) were built on the upper slopingshelves of the 12-27 morants (P. pelagicus)have been captured with padded m high cliff and were readily accessible.In addition, 51 leghold traps (Tenaza 1966). adultswere capturedwith a noosingpole modified from a similar technique used by Edgar (1968) for Australian Great Cormorants in breed in colonies on (Sula serrator). A diagramand detailsof the device seacliff ledges,on the level ground at the tops of cliffs, are shownin Figure 1. The noosingpole was constructed or on small,coastal islands. They rarely nestin trees (God- by a local tinsmith. frey 1966, pers. obs.),a habit common to other races of this widespreadspecies elsewhere (Cramp and Simmons 1977).While they often nestapart from other ,they PresentAddress: Department of Biology,University of Prince Edward occasionallyshare nesting colonieswith Double-crests. Island, Charlottetown, Prince Edward Island C1A 4P3

Figure 1. Diagram of noosing pole used to capture adult Great Cormorants.

A. q2-inthinwall steel tubing, 120 in B. %-in thinwall steel tubing, 30 in C. h-in tin or steel band D. s/16-insteel cable, 96 in E. %-in nipple E %-in copper tubing, 48 in G. %-in clamp

G F E ..

A B C

Page 76 North American Bander Vol. 10, No. 3 To capture a bird, the steel cable forming the noosewas Literature Cited fully extendedby sliding the outer steel tube (to which the cable is attached)forward. The noosewas then moved Cramp, S., and K.E.L. Simmons(eds.). 1977. The of slowly towards the bird and carefully slipped over the the western Palearctic.Vol. 1. Oxford University Press, bird'shead and down to coverthe upperwings and breast. Oxford. If lowered further, the bird simply steppedout of it. Once Edgar,R.L. 1968. Catching colonial seabirdsfor banding. in position,the nooseis tightenedby slidingthe outer steel Bird-Banding39:41-43. tube back to pin the wings firmly to the body. The bird Godfrey, W.E. 1966. The birds of . National was then either lifted away from the nest or held in place. Museum Canada Bull. 203. A helper was required to grab the bird. The entire pro- Hogan, G.G. 1979. Breeding parameters of Great Cor- cedure generallytook 5 to 15 minutes. Somebirds were morants (Phalacrocoroxcarbo carbo) at mixed species captured easily, while others would not tolerate the ap- colonies on Prince Edward Island, Canada. M.Sc. thesis. proach of the noose. Once captured and processed,the Brock University, St. Catharine's, Ontario. birds was released, whereupon it invariably flew to the ß 1983. P.E.I. cormorant census, 1983. Report to water, bathed, and returned to the nest, usually within and Wildlife Division, P.E.I.Department of Community 10to 15 minutes.Neighboring birds exhibited little distur- and Cultural Affairs, Charlottetown. bance.Aerial predators such as gulls (Larus spp.) and Nor- Lewis, H.F. 1929. The natural history of the Double- thern Ravens(Corvus corax) did not frequentthis colony crested Cormorant [Phalacrocorox auritus auritus while the observerswere present.The techniquework- (Lesson)].Ru-Mi-Lou Books, Ottawa. ed bestwhile smallto half-grownchicks were in the nest. McNicholl, M.K. 1983. Use of noosing pole to capture Adults were less likely to tolerate the closepresence of Common Nighthawks. NABB 8:104-105. observerswhen there were only eggs,and larger chicks Tenaza, R.R. 1966. A method for trapping cormorants. scramblefrom their nests if disturbed and may fall off Bird-Banding37:207-208. the cliff. (Eastern)

The technique describedhere is a safe, low-disturbance method for capturing adult Great Cormorants at their nests. Behavioral differences may exist between cliff- nestingand ground-nestingbirds regardingtheir tolerance to disturbance.

Acknowledgments Researchonboth cormorant species wasconducted dur- ing graduatestudies by the author under the supervision of R.D. Morris, BrockUniversity, St. Catharine's,Ontario. Field assistanceduring noosingoperations was provided by LawrenceGray and Ada Judson.Financial support was provided by the Prince Edward Island Fish and Wildlife Division, a National ResearchCouncil of Canada grant to R.D. Morris, and an Ontario Graduate Scholarshipto the author. The manuscriptwas improved on the basis of commentsby M.K. McNicholl,Daryl Guignion,and Ian MacQuarrie.

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