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Pine GrosbeaksUsing Bird Feeders

byRon Pittaway

IntroductionThe Pine Grosbeak (Pinicola

mucleator) staged a majormovement into southern Ontarioduring the win ter of 1985-86 (Weir1986). An unusual aspect of PineGrosbeak behaviour in that winterwas the species' widespread use ofbird feeders (Weir 1986).

ObservationsI first noted Pine Grosbeaks eatingsunflower seeds at a feeder on 5January 1986. Throughout thatwinter, small flocks of PineGrosbeaks, of up to a dozenindividuals, regularly visited byfeeder in Minden and many otherfeeders (pers. obs.) in HaliburtonCo., Ontario. My last observation in1986 was of two females at myfeeder on 28 March. At feeders,Pine Grosbeaks were oftendominated by the more aggressiveEvening Grosbeaks (Coccothraustes

vesper-tinus). They tended tofrequen t feeders more at middayafter the Evening Grosbeaks hadlefL In 1986, Ron Tozer (pers.comm.) made his first observationsof Pine Grosbeaks at feeders in theDistrict Municipality of Muskoka.On one occasion at Dwight, he

observed six Pine Grosbeaksaggressively fighting with severalEvening Grosbeaks over sunflowerseeds.

These observations arenoteworthy because in over 30 yearsI have only once before observedPine Grosbeaks at a bird feeder (inJanuary 1984, when I observed asmall flock at a feeder nearHaliburton Village, HaliburtonCo.), although there have beenmany "irruptions" of this species insouthern Ontario during that time(Speirs 1985). Crumb (1981)reported a female Pine Grosbeak ather feeder in upstate New York. Sheconcluded, "although I havediscussed this with many peopleover the years, I have never knownof anyone who knew of a PineGrosbeak actually eating at afeeder." As a result of her note,Dorothy Crumb (pers. comm.)learned from Kim Eckert (in litt.) ofDuluth, that "Pine Grosbeaksroutinely eat sunflower seeds atMinnesota feeders." Pine Grosbeaksalso have been reported to usefeeders in Nova Scotia (Tufts 1961).

Ron Pittaway, Box 619, Minden, Ontario KOM 2KO

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DiscussionWhy Pine Grosbeaks have not un tilrecently been observed to usefeeders in southern Ontario andupstate New York, but haveelsewhere, is not known. I offerthree (probably interrelated)possible explanations.

First, Newton (1972) stated thatfood habits ofcardueline finchesare learned from conspecifics andby trial and error. Thus, the use offeeding stations by Pine Grosbeaksappears to be a learned behaviour.Since most of the Pine Grosbeaksthat visit southern Ontario breed inremote areas where there are fewfeeders, their infrequent irruptionsmay mean that some populationshave not learned to use feeders.

Second, Pine Grosbeaks feedextensively on tree buds (Newton1972), and so they may not be asdependent on feeders as are otherwin ter finches when tree seeds andberries are at low levels. However,their appearance at feeders in 1986may have been due to the failure ofan important unrecognized foodsource. Weir (1986) attributed theiruse of feeders to "a shortage ofwildseeds and berries"~

Third, Tufts (1961) believed thatincreasing numbers of EveningGrosbeaks caused a decline in theuse of feeders by Pine Grosbeaks inNova Scotia. Therefore, PineGrosbeaks may not go to feeders insouthern Ontario and New YorkState because of the presence atthose feeders oflarge numbers ofmore aggressive species such asBlueJays (Cyanociua cristata) and

ONTARIO BIRDS AUGUsr 1989

Evening Grosbeaks. However, whena large irruption of Pine Grosbeaksoccurs, there may be sufficientnumbers present that someindividuals seek out additional foodsources such as feeders. Only smallnumbers may actually go to feeders,and these may be the moreaggressive individuals that are readyto compete with other birds. PineGrosbeaks using feeders could berare in southern Ontario and NewYork State because those areas donot often have large numbers ofthis species. Perhaps they do go tofeeders more frequen tly inMinnesota because that stateusually has higher numbers ofPineGrosbeaks in win ter than dosouthern Ontario and New York.Therefore, Minnesota morefrequently has Pine Grosbeaks thatare habituated to feeders.

There may be betterexplanations of these observations.Please contact me ifyou have adifferent interpretation.

EpilogueIn January 1988 I observed one tothree Pine Grosbeaks several timesat the feeders of the Leslie M. FrostNatural Resources Centre,Haliburton Co. The observation ofPine Grosbeaks at feeders wouldhave been considered exceptionalbefore 1~86. It will be interesting tosee if the use of bird feeders by PineGrosbeaks in southern Ontarioincreases in future years.

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Acknowledgements Literature citedI am grateful to Mike Buss, Dorothy Crutllb. D. W. 1981. Pine Grosbeak eating at

Crumb, Barb Elliot, Rory MacKay, feeder. The Kingbird ~1:15~.

Nlwttm, I. 1m. Finches. William Collins SonsDan Strickland, and Ron Tozer for. and Co. Ltd., London, U. K.

their assistance during the Splin,J M. 1985. Birds ofOntario. Vol. 2.

preparation of this article. Nawral Heritage/Nawral History Inc.,Toronto.

T'lI.fts, R. W.1961. Birds of Nova Scotia. TheNova Scotia Museum, Halifax.

MWit; R. D. 1986. The winter season. Ontarioregion. American Birds 40:274-277.

NotesRoss' Goose Breeding on Akimiski Island,

Northwest Territories

During part ofJuly 1984, Peter Photographs of the adult maleBurke and the author were Ross' and the goslings (Figs. 1 andparticipating in the Ontario Breeding 2) were obtained both in the handBird Atlas project in northern and in the pens. The adult did notOntario. Part ofour assignment appear to be a hybrid and exhibitedincluded assisting the Ontario features one would expect in aMinistry of Natural Resources and "pure" Ross'. The juveniles werethe Ohio Deparunent of Natural similar to young Snow Geese, butResources staff with a goose differed in that they were muchbanding program. whiter in appearance. No notable

On 1~ July 1984 we were difference was found in billinvolved in gathering wild geese structure between them and younginto pens as part of this projecL Snow Geese. They were, however,One flock of Canada Geese (Bmnta much more aggressive than thecanadmsis) was being "rounded up" young Snow Geese while in theon the northwest shoreline of pens.Akimiski Island, Northwest Photographs were submitted toTerritories. Included in the flock the Royal Ontario Museum,of approximately 50 geese were Toronto, for evaluation. Theseveral Canadas, two or three Snow impression of the reviewers was thatGeese (Chen caerulescens) , one the birds were likely pure juvenile"Blue" Goose, and an adult male Ross' Geese, but the possibility ofand two juvenile Ross' Geese (Chen hybridization could not be ruledrossia). out definitively.

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