I was going to respond with the same exact sentiment as Christopher Wood!! I couldn't agree more. Anything with color and/or a song is put in a cage in Latin America, sold, and cherished by its owner. As a student at Northern Arizona University, I had the opportunity to spend some time in their vertebrates collection. In there were a few trays full of South/Central American goodies that had been confiscated at the AZ/Mex border. Things like San Blas Jay and Masked Tityra stick in my mind. People will smuggle just about anything over the border. I doubt anybody would try to legitimately get some of these things through customs since it's illegal. Who knows what else customs gets, and who knows what else gets through. I really don't think Americans appreciate the situation in Latin America. In the land of hand sanitizer and golden retrievers, we don't find it appealing to have Brown-backed Solitaires hanging out in the living room, but just sit back with a margarita in any Mexican town at dusk and bask in the glory of their tremendous songs wafting from the porches and open windows all around. The Rufous-backed (Variable) Hawk is probably an escapee. Raptors of all sorts are kept in captivity around the World. The Orange-billed Nightingale-Thrush could very well be and escaped cage bird, too. Why not? Why would one fly thousands of miles out of its way, crossing vast tracks of suitable habitat on its way, to settle in SD?? Why couldn't it have been put in a cage by an immigrant from down south, carried across the border (sans paperwork, of course) and up to SD where it eventually escaped/was let go? Seems more plausible than natural vagrancy to me. Same thing with that Thick-billed Parrot down in NM a few years ago. Middle of nowhere, crap habitat, next to train tracks. Natural vagrant? Yeah right. The probability that these birds arrived with human assistance is vastly higher than the probability of natural vagrancy. Plain and simple. Humans have their fingers in everything, if you haven't noticed. "It may take a committee of experts to determine its wild vs ex-captive status."- I disagree with this. No committee of experts has a magic crystal ball that can determine provenance of birds like this. No one's speculation is more valid than another's. If the evidence isn't there, it isn't there. I was thinking long and hard about the mechanism of natural vagrancy in this case. If one thinks about the evolution of migration in other Zonotrichia sparrows, it has to be considered that at one point they were sedentary, then started to migrate. Single founding individuals probably started things off. But, it is highly unlikely that these pioneers started in huge leaps and bounds. It is more likely that they ventured forth at about the same rate that habitats were changing with climate, infiltrating suitable habitat. I don't think a single individual of a sedentary species just up and flies thousands of miles north of its range to successfully found a new population. It would happen slower, with birds progressively making their way north through suitable habitat (which there is ample for a Rufous-collared Sparrow), and eventually the harsh realities of Northern Hemisphere winters would spur the winter retreat, then in following seasons the birds would return, etc., and soon there's a migratory pattern. A bird like the Rufous-collared Sparrow is closely associated with Humanity, and it is not far-fetched to surmise that one hitched a ride with one of us. It is far-fetched for a non-migratory sparrow to up and fly such a great distance, and to survive. Neat stuff. Christian Nunes Boulder, CO [email protected]
From: [email protected] To: [email protected] Subject: Re: [cobirds] Why is the Rufous-collared Sparrow likely an escaped cage bird? Date: Tue, 10 May 2011 09:33:35 -0600 Oops, I meant to say “Chris Woods”, not “Chris Nunes” (sorry Chris, and Chris). Nick Fort Collins CO From: Nick Komar Sent: Tuesday, May 10, 2011 8:17 AM To: [email protected] Subject: [cobirds] Why is the Rufous-collared Sparrow likely an escaped cage bird? With all due respect to Chris Nunes’ knowledge of birds both north and south of the border, his suggestion that the reported RUFOUS-COLLARED SPARROW (Zonotrichia capensis) may be a released captive bird should not be construed as the probable source for this Zonotrichia sparrow. Millions of Rufous-collared Sparrows occupy their native range from the southern tip of Mexico to the southern tip of South America (and also the Caribbean Island of Hispaniola). How many are caged? What is the probability that one of those caged sparrows was transported or imported to the US? And that it was allowed through customs (which would require numerous permits)? And that it escaped? And that it ended up away from a major zoo location or human population center? And that it appears to have set up a territory in its native habitat in a montane village? Now, what is the likelihood that a genetic mutation has led to one (or many?) of those sparrows trying to migrate? This same mutation (or a similar one) has occurred, over millenia, with successful results for many hundreds of species that migrate from Central America or northern South America to North America. Even in recent rears, we have seen some evidence of odd migrants from the south turning up in Colorado and vicinity. Take, for example, the White-eared Hummingbirds, and the Broad-billed Hummingbird, and the Brown-crested Flycatcher. Perhaps better examples are the Orange-billed Nightingale-Thrush in South Dakota, and the Red-backed Hawk (from southern South America). How is the Rufous-collared Sparrow any different from the Orange-billed Nightingale-Thrush, a species which undoubtedly is also captured and placed in captivity on occasion. There are numerous examples of individuals of migratory species losing their urge to migrate (such as Blue-winged Teal that have become resident in Colombia). It stands to reason that on occasion we observe a migrant from a sedentary population, which may be the case for this Rufous-collared Sparrow. By the way, all other Zonotrichia sparrows are migrants, including White-crowned, Golden-crowned, White-throated and Harris’s Sparrows. So, I recommend trying to observe the Rufous-collared Sparrow in Georgetown (please do not disturb it or play tapes for it, so that others may too enjoy it). It may take a committee of experts to determine its wild vs ex-captive status. I personally suspect that the probability of it being a wild migrant, albeit low, is not negligible, and should be seriously considered by the Colorado Birds Record Committee. Nick Komar Fort Collins CO-- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/cobirds?hl=en. -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/cobirds?hl=en. -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/cobirds?hl=en.
