[Pollinator] Hummingbird Pollinators on Chayote #1

[Bill Hilton Jr. (RESEARCH)]

During 11 citizen scientist expeditions to Guanacaste Province in western Costa Rica I've banded nearly 800 Ruby-throated Hummingbirds (RTHU). These long-distance migrants from North America feed on nectar-rich blossoms of non-native Aloe Vera in large plantations that produce juice used in everything from suntan balm to health foods. Aloe propagates clonally, so RTHU don't seem to play any pollination role--nor do the other eight hummer species we've captured incidentally.

However, I've just returned from my first trip to EASTERN Costa Rica to study and band a previously undocumented population of RTHU at Ujarrás in the Orosi Valley. There the wintering RTHU are nectaring on monocultures of Chayote (Sechium edule), a native squash that grows on arbors that cover 1,500+ acres of rich bottomland. Because agriculturalists have used insecticides for years to protect the Chayote from various six-legged pests there remain very few insect pollinators. That the Chayote still produces a commercially viable crop for domestic use and export indicates ruby-throats and other non-migratory hummers are doing most of the pollinating--a phenomenon acknowledged even by local farmers.

In my current installment of "This Week at Hilton Pond" I offer a day-by-day account of our latest expedition and thought members of the Pollinator listserv would be interested in reading the account. Next week I'll devote a follow-up installment to photos of ALL the kinds of hummers we caught (13 species, plus 11 more observed but not captured!) and include further discussion of the pollination situation.

The current edition for 12-20 November 2011 is at http://www.hiltonpond.org/ThisWeek111112.html

Happy (Neotropical) Nature Watching!

BILL

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RESEARCH PROGRAM
c/o BILL HILTON JR. Executive Director
Hilton Pond Center for Piedmont Natural History
1432 DeVinney Road, York, South Carolina 29745 USA
office & cell (803) 684-5852
fax (803) 684-0255

Please visit our web sites (courtesy of Comporium.net):
Hilton Pond Center for Piedmont Natural History at http://www.hiltonpond.org 
"Operation RubyThroat: The Hummingbird Project" at http://www.rubythroat.org

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