Churchill Community of Knowledge

Permanent URI for this community

https://hdl.handle.net/10315/8089

An online resource of data and media about the Town of Churchill, its people, Wapusk National Park, and the extensive research supported by the Churchill Northern Studies Centre. This Digital Archive is hosted by the Yorkspace Institutional Repository, York University, Toronto. The first collection in the project celebrates the life and work of Professor Bob Jefferies, who carried out field research in ecology in and near Churchill, for 30 years.

Robert L. Jefferies Collection

How to submit an item: Undigitized items (lke your old Kodachrome slides) can be sent to Ms. Netta Untershats and her team for digitizing.

We will send you a receipt for the items, and send them back to you after they are digitized. Please include any information about the item - in the case of photos, what, where, when and who? And, please remember to confirm in writing in an email or letter, that you are the owner of the image.

QUESTIONS? For items related to Bob Jefferies and other La PĂ©rouse Bay research and to send digitized items, please contact:

Dawn Bazely: dbazely@yorku.ca

Netta Untershats: nettauntershats@osgoode.yorku.ca

For items relating to the broader Churchill community: Mike Goodyear and Leeann Fishback of the Churchill Northern Studies Centre, can advise you about items that do not directly relate to Prof. Jefferies’ life and research, but which do relate to the broader Churchill community, including the Studies Centre.

goodyear@churchillscience.ca

fishback@churchillscience.ca

To browse by particlar area, please click on one of the hyperlinks below:

Camp Finney

Hudson Bay

La PĂ©rouse Bay

Wapusk National Park of Canada

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Browsing Churchill Community of Knowledge by Author "Bradley, R. W."

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    ItemOpen Access
    Sex Differences in Nest Visitation by Chick-Rearing Marbled Murrelets
    (University of California Press, 2002) Bradley, R. W.; McFarlane Tranquilla, L. A.; Vanderkist, B. A.; Cooke, F.
    We report a significant male bias in dawn and dusk nest visitations of breeding, radio-marked Marbled Murrelets (Brachyramphus marmoratus) during the chick rearing period in Desolation Sound, British Columbia, Canada, from 1998-2000. Overall visitation rates of males during chick rearing were 1.3 times greater than those of females. Dusk visitation rates by males with active nests were 1.8 times greater than those of females. Male visitation rates were similar between early and late chick rearing, both within and among individuals. However, female visitation rates duringl ate chick rearingw ere significantlyl ower than female rates early in rearing, both within and between individuals. In addition, between-sex comparisons of nest visitation during early and late chick rearing showed significant reductions in female effort relative to males, only during late chick rearing. These results suggest that male birds may provision chicks more often than females, especially during the last half of chick rearing. These findings offer a behavioral explanation for the annual male bias of birds flying inland during the chick rearing period at Theodosia Inlet in Desolation Sound from 1994-1999. Although female- biased provisioning has been documented in several species, male-biased provisioning has not been widely reported in other alcids.

All items in the YorkSpace institutional repository are protected by copyright, with all rights reserved except where explicitly noted.