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.
