Subject: Steller's Jay feeding on snow
Date: Feb 17 23:36:33 2001
From: Jim McCoy - jfmccoy at earthlink.net


I think that as suggested, familiarity and learned behavior is probably
the issue. Corvids in the northeast, including blue jays, crows, and
ravens, don't hesitate for a moment to forage in the snow; presumably
Puget Sound populations of Steller's Jays aren't so used to the white stuff.

Jim McCoy
jfmccoy at earthlink.net
Redmond, WA



-----Original Message-----
From: Fred Sharpe [mailto:fsharpe at sfu.ca]
Sent: Friday, February 16, 2001 6:38 PM
To: tweeters at u.washington.edu
Cc: Concerning Cautious Corvids:
Subject: Re: TWEETERS digest 2404



Concenring Cautious Corvids:

One could argue that birds exhibiting trepidation or neo-phobia are in fact
clever. A basic definition of animal intelligence is an ability to project
into the future and weigh the outcomes of various actions. From an
evolutionary perspective, frequently the best longterm payoff is to "stay
in the game". Thus the optimal tactic may be avoid novel situations, at
least until a conspecific has tested the water. Foraging activities often
results in a temporary decrease in vigilance, increasing the risk to
predators. Probing the head into a substrate to retrieve a food item is a
classic example.

Alternatively, the cautious behavior exhibited by the jays may be linked to
"aversion leaning" whereby the birds had a previous negative experience
with foraging on snow. Soft snow may impair an individuals ability to
avoid predators by executing a speedy takeoff. For example, the compliant
substrate may not permit a solid launch pad, or the snow may impair wing
mobility. A split second of sensory depravation may seen like an equable
tradeoff in order to procure a tasty peanut. However, you can bet that
this action wont be lost the accipter lurking in the nearby thickets.

At the simplest level, the jays may have an instinctual avoidance of
laminar surfaces, perhaps associated with their general hydrophobic
tendencies.

fred sharpe,
SFU fsharpe at sfu.ca

><>< <>< <>< <>< <>< <>< <"}}}}}}}><{
>Behavioral Ecology Research Group
>Dept. of BioSciences
>Simon Fraser University
>Burnaby BC V5A 1S6 Canada
>phone: (604) 291-4374 Lab
> 291-5864 Office
>fax: (604) 291-3496
>email: fsharpe at sfu.ca
>
>Alaska Whale Foundation
>4505 University Way NE #438
>Seattle WA 98105
>Alaska BC Whale Foundation webpage:
> http://www.biol.sfu.ca/berg/whale/abcwhale.html
>
>