Neglected sending this to the whole group, as intended. Dave From: daleather...@msn.com To: quetza...@comcast.net Subject: RE: [cobirds] Boulder surprising hawk kill Date: Fri, 27 Feb 2015 10:28:38 -0700
David, Nick, Gary, et al, Interesting observations, all. I would throw in seeing a Northern Pygmy-Owl fly past with a Steller's Jay in its talons one time in Rist Canyon west of Fort Collins. The owl is 2.5 oz (70g), the jay 3.7 (105g). The literature talks about a pygmy-owl that was threatening a Dusky Grouse (1050g) , but that report was unclear as to whether it was a predator-prey thing or territorial harassment thing. For sure, hunger and brood protection are both strong motivators. As for Sharp-shin numbers, I was always under the impression the majority migrate south. Maybe how many stick around is somehow driven by autumn weather and the sudden cold snap we had in early November made up the minds of birds sitting on the fence, so to speak. Sort of like kestrels, Great Blue Herons, meadowlarks and other semi-hardy species that we have a few of in winter, but not in bulk. Just a thought. Dave Leatherman Fort Collins Subject: Re: [cobirds] Boulder surprising hawk kill From: quetza...@comcast.net Date: Fri, 27 Feb 2015 10:04:41 -0700 CC: cobirds@googlegroups.com To: djwalt...@comcast.net Sharpies take Eurasian Collared-Doves on a regular basis. The dove is almost 50% larger than the hawk by mass. This brings up a question: why are there not more Sharp-shinned Hawks around? There must be more influential constraints on the hawks population than winter food supply. Any thoughts on what those constraints might be? Nick Komar Fort Collins CO Sent from my iPhone On Feb 27, 2015, at 9:29 AM, David Waltman <djwalt...@comcast.net> wrote: I just witnessed a Sharp-shinned Hawk successfully kill a Steller's Jay. It's sitting on the ground eating the jay right now. The Steller's Jay is about the same size as the hawk, although the Sharp-shinned would outweigh the jay at about 5 oz. vs.3.7 oz. I'm amazed that a Sharp-shinned Hawk would go for a bird that large. David Waltman Boulder County foothills, 1/2 between Boulder and Lyons -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+unsubscr...@googlegroups.com. To post to this group, send email to cobirds@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/1558816715.19306476.1425054599681.JavaMail.zimbra%40comcast.net. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+unsubscr...@googlegroups.com. To post to this group, send email to cobirds@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/B0E4A4EC-CA16-4E08-9211-1A840FEA3DBB%40comcast.net. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+unsubscr...@googlegroups.com. To post to this group, send email to cobirds@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/SNT148-W3457C6931CF536F01C7C14C1150%40phx.gbl. For more options, visit https://groups.google.com/d/optout.
