In addition to the WA and BC birds Steve mentioned, there is an additional record from Nebraska in January 2006, which was not accepted because of uncertainty regarding provenance:
https://birds.outdoornebraska.gov/pink-footed-goose/?fbclid=IwAR3OYUI9K3vc69fvsrr5Sh0ioAiRiYNOvSioe3th9tYD6ZzOAp-k9rnvef8 That would make 4 separate occurrences of PFGO west of the Mississippi in the past 15 years. In my opinion, that's fairly solid evidence of a pattern of vagrancy for an infrequently-captive bird, which should probably be about that rare. This is a large goose that breeds in the North Atlantic, regularly shows up in the Eastern US, and by all accounts should be physically capable of making it to Colorado as a natural vagrant. Just food for thought. Fantastic find Steve!!! Best, Alec Hopping On Tuesday, December 11, 2018 at 7:52:03 PM UTC-5, Steven Mlodinow wrote: > > Greetings All > > The Pink-footed Goose (and friends, about 30 Canadas and 5-10 Richardson's > Cacklings) spent nearly the entire day in the large pond adjacent to Idaho > Creek Wildlife Area. The bird was typically best seen from along Weld > County Road 7, and though our cars were sticking a wee bit into the street, > no one came to shoo us off; indeed several locals came by for interested > and friendly chats. > > The wild vs non-wild question is unknowable. No bands, hind-toes intact. > So, at least no slam dunk signs of prior captivity. > Washington State had two adults appear on its outer coast in December > 2003. I was part of the WBRC when we reviewed the birds. Many of us felt > the odds of the birds being wild were high, but decided to hold off on > accepting the species onto the state list -- waiting to see if a pattern > developed > > Why did we think the birds had a goodly chance of being wild. > 1) Wild population was quickly increasing and had spread to Greenland > 2) We enlisted the aid of some of the country's most respected > aviculturalists (and avian curator at the Seattle zoo), and found only one > aviculturalist that kept this PF Goose (I can't remember where - but in > Canada, 4 birds total, all well ensconced at the time). Don't know why this > species is rare in captivity in North America but it is. This is in > contrast to Barnacle Goose, which is not rare in captivity. > 3) We looked at the migration path of Iceland breeding birds to nw Europe > (the species' usual wintering ground). Turn that around 180 degrees (a > common misorientation pattern in vagrant birds), travel the same distance, > and that puts the birds in central Saskatchewan (as I recall). Continue > that same direction... and you are on the Washington coast. Hook up with > other geese in Saskatchewan, and you might find yourself in CO. > > Also, I think if you change the breeding location (Iceland vs Greenland), > that 180 degree error might land the bird in CO. > > Sadly, the eBird reviewers for WA decided to be very conservative and did > not put those well documented birds on eBird, which makes research into > these matters more challenging. There were, interestingly, another 2 PF > Geese on southern Vancouver Island, BC (not far from the 2003 WA birds) > during the 2016-2017 winter. Same pair??? There are no other accepted PF > Geese on eBird west of NY and PA. > > Below are stats on the population increase of PF Goose. > > Taxa with rapidly increasing populations are far more prone to vagrancy, > explaining why Aleutian Cackling Geese have been found as vagrants far more > than minima Cackling Geese over the last decade, despite relatively similar > populations and migration distance. > > I hope this provides some illumination if not 100% conclusions > Steve > > > > https://monitoring.wwt.org.uk/our-work/goose-swan-monitoring-programme/species-accounts/pink-footed-goose/ > > 2017 515,852 17.1 1.85 > 2016 481,341 18.8 1.75 > 2015 536,871 18.8 1.89 > 2014 393,170 19.4 2.01 > 2013 372,074 17.3 2.16 > 2012 359,175 21.1 2.30 > 2011 260,325 8.5 1.77 > 2010 297,798 19.9 2.32 > 2009 364,212 17.3 1.87 > 2008 351,188 22.9 2.08 > 2007 284,405 20.0 2.27 > 2006 230,123 19.3 2.20 > 2005 302,774 18.1 1.7 > 2004 276,644 19.4 2.1 > 2003 280,998 19.0 2.19 > > -- 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 [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/9ad73a1b-651c-42ca-8d44-28e2237f1434%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
