I compiled some records/reports of Crested Caracara north of its normal range in Florida and Texas-Louisiana in eastern North America (see list below). I grouped these by year of occurrence so the dramatic increase in the past 2-3 years can be appreciated. The list for 2013 groups the New Jersey records thought to involve the same individual, one of which, a bird at Cape May, may be the same as the Nova Scotia according to Ian McLaren. I did not group the Nova Scotia records by individual; it appears at least two were involved, one being the same in the Halifax area and this past winter on Cape Breton Island. This makes the 2013 list look longer than it otherwise might appear.
To help identify individuals, good photos of the birds in flight are especially welcome. The shape of the cere, wear and notching patterns in the flight feathers, and potentially even the pattern of black bars in the outer primaries might help fingerprint birds. If you have such photos, please share them.
The most recent and nearest occurrence to Maine is of a bird photographed at Miramichi, New Brunswick, 19-21 April 2014. It wouldn't surprise me if our bird is the same as that one (photos of the NB bird are not good enough to say more than both are definitive plumage adults that look similar). In California, a review of records through 2011 showed that 60+ observations (49 records) involved only 11 individuals, one bird traveling extensively over 8 years and making a 500 mile journey northward within 11 days. So, the pattern of long-distance dispersal we are seeing here has been observed in western N. Am. along the Pacific Coast for a longer period of time. (There are records north to British Columbia.) Some of the records seemed to occur in pulses, with 2001-2002 being one pulse across much of North America, and then another larger one mostly to the west beginning in 2005. Another recent spurt toward northeastern North America clearly began in 2012; some observations may involve birds returning or circulating within the Northeast since arriving.
The pattern of dispersal is similar, though different in key ways, to the bifurcated advance of Great-tailed Grackle, which spread northward and westward on one front from west Mexico and Arizona (now nesting well north along the Pacific coast) and north and northeast from east Mexico and Texas (a front that seems to have slowed or stalled). While eventual breeding and range expansion has not been seen as much in North America, just the increased vagrancy, South American caracaras have expanded into deforested areas (mainly following livestock). The impulse for these long-distance forays of individual caracaras is a puzzle. These are birds that can roam widely at times, appearing at burns for example, and so have some innate ability to search far and wide for food. When they don't need to search, however, caracaras stay put and hold territories that are not that large. My first guess would be that drought and landscape changes in the core part of the range from eastern Mexico to Texas, rather than from Florida, is driving some of these pulses of long-ranging caracaras. It could be both areas. Black-bellied Whistling Ducks certainly did that, pushing into Texas on one front and into Florida likely from Mexico across from the Yucatan on another front.
All that aside, it's a blast to see one in Maine. I hope others can see it too.
Louis Bevier
Fairfield
Records of Crested Caracara northward in eastern North America (Newfoundland awaits you!!)
1892
July, Ontario (first record for Canada)
[see George Atkinson's account - http://biodiversitylibrary.org/page/39457429]
1994
July, Minnesota (see http://moumn.org/loon/view_frame.php?page=59&year=1995)
July, Ontario (Pelee)
1999
January, Massachusetts
2002
July, Ontario (Fort Albany)
October, New Brunswick
2007
May, Massachusetts
2011
August, Kansas
2012
August, Quebec (unconfirmed)
Sep-Oct, New Jersey (West Windsor & Columbus)
2013
January, New Jersey (Cape May)
January-February, New Jersey (New Gretna & Galloway)
January-May, New Jersey (Sharptown)
March, Nova Scotia (Lawencetown)*
May, Nova Scotia (Monastery, reported)
July, Nova Scotia (Canso)*
May, Nova Scotia (Middle West Pubnico)
August, Quebec (unconfirmed)
December, Nova Scotia (Port Hawkesbury)*
2014
January, Nova Scotia (Cape Breton Is.)*
April, New Brunswick
May, New Jersey (Cape May)
May, Wisconsin
August-Sept, Maine (Unity Twp. and Benton; Norridgewock)
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