Daily consumption of nectar by Rufous Hummingbirds at a feeder in Victoria, British Columbia

Geoffrey L. Holroyd1 and J. Cam Finlay2


1 Box 33, Site 2, RR 2, Tofield, AB, T0B 4J0 email: geoffholroyd@gmail.com
2 270 Trevlac Place, Victoria, BC, V8X 3X1


Abstract: Estimating the number of hummingbirds at a feeder is difficult because of the activity and brief visits by multiple birds. The number of Rufous Hummingbirds (Selasphorus rufus) at feeders near Victoria, British Columbia, was estimated from hourly trapping and recapture data. After 6.5 hours of trapping effort, 56 hummingbirds were banded. Using mark-recapture results we estimated 72 hummingbirds were present. On the day before trapping, hummingbirds drank 345 ml of 25% sugar water or an average of 4.8 ml each. We estimated that each Rufous Hummingbird drank 1.4 times its own weight each day. We estimate 52 hummingbirds would drink 250 ml (1cup) in a day.

Key words: Rufous Hummingbird, Selasphorus rufus, mark-recapture, syrup consumption rates, British Columbia.


PDFicon Holroyd, G.L. and J. Cam Finlay. 2016. Daily consumption of nectar by Rufous Hummingbirds at a feeder in Victoria, British Columbia. British Columbia Birds 26:32–34. First published on-line October 2015.

 


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