MD Osprey ... FYI ...


>From: "Alvaro Jaramillo" <>
>To: <>,
>         <>,
>         <>
>Cc: <>,
>         <>
>Subject: RE: Southern Lapwing chase - 6/22
>Date: Fri, 23 Jun 2006 10:25:26 -0700
>
>Jay
>
>     Thanks for the comments, which are great points, although I would 
> argue that there is not enough information on what South American 
> tropical birds do, particularly waterbirds to come to any rigid 
> conclusion regarding Southern Lapwings. The southernmost population of 
> Southern Lapwing (fretensis) is indeed migratory. However, vagrant 
> records north of the range of Southern Lapwing have never included any of 
> the southern forms (fretensis or chilensis). These forms, which I think 
> may be better considered a separate species, are closely tied to 
> temperate climates; they are found nowhere that is tropical. The Southern 
> Lapwing has undergone a rather rapid expansion into Trinidad, and then 
> Tobago. As these are islands, obviously some birds must have been making 
> longer distance movements even though they are considered non-migratory. 
> The same seems to be the case in Central America where there are now at 
> least a couple of records in Costa Rica, and one record from the Yucatan 
> in Mexico (Martin, J.P. 1997. The First Southern Lapwing Vanellus 
> chilensis in Mexico. Cotinga 8: 52 -53). The Mexico bird was a 
> cayennensis, and I recall seeing photos of a Costa Rica bird, also 
> cayennensis. Assuming these are wild birds, it does seem that cayennensis 
> is the one that wanders north, not the southern forms. One has to keep in 
> mind the distances involved here, the migratory southern subspecies 
> winter in the summer hemisphere latitude equivalent to that of northern 
> California. So they winter over 35 degrees in latitude south of the 
> equator! The subspecies cayennensis on the other hand is much, much 
> closer to the US, breeding in the northern hemisphere. Still in this 
> distance and latitude train of thought, the vagrant from the Yucatan was 
> much closer to Florida than it was to its regular range; the Yucatan is 
> at the latitude of Cuba. I have examined a vagrant record (specimen) from 
> the Falkland Islands and it was not of the Patagonian migratory 
> subspecies, fretensis, but the more northern (cayennensis group) form 
> lampronotus! It seems like cayennensis does move around, although the 
> nature of the movements are not understood or documented at this time. So 
> putting it all together, I do think that cayennensis is the most likely 
> form to show up in the US as a wild bird, not the temperate migratory 
> birds from the far south.
>             The question of migration in the tropics is a big unknown. 
> There are big movements of birds in the South American tropics which are 
> not understood yet, many of these are migratory movements. Several 
> species of hummingbirds and even parrots (Lilac-tailed Parrotlets) seem 
> to disappear from Trinidad and Tobago for periods of time, I am sure they 
> are migrating to mainland South America during these times. Similarly, 
> some swifts migrate to Trinidad, Tobago and the southern Lesser Antilles 
> to breed, and winter elsewhere. A well documented case of migration 
> within the tropics in South America is that of the Azure Gallinule, a 
> species that does show up as a vagrant now and again in the temperate 
> region. Many waterbirds appear to make regular migrations within the 
> tropics, or even out of the tropics (cinarescens Black Skimmer which 
> breeds in the Amazon and winters outside of the basin). Whistling-Ducks 
> make regular movements which are not understood as of yet in South 
> America, as do many other ducks. The case of the Gallinule is an 
> interesting one. The bird was thought to be a resident in tropical 
> America until a careful study of dates of sightings and specimens 
> revealed seasonality in their occurrence, so they appear to be migratory. 
> Here is a link to the paper:
>
>http://elibrary.unm.edu/sora/Wilson/v102n03/p0380-p0399.pdf
>
>I don't think that one has to invoke hurricanes as a cause for vagrancy, 
>but you never know.
>
>Regards
>
>Alvaro
>
>Alvaro Jaramillo
>Biologist
>San Francisco Bay Bird Observatory
>P.O. Box 247
>Alviso, CA 95002
>http://www.sfbbo.org
>
>
>
>----------
>From:  [mailto:[log in to unmask]]
>Sent: Friday, June 23, 2006 9:18 AM
>To: ; ; 
>Cc: 
>Subject: Re: Southern Lapwing chase - 6/22
>
>Just to add a few comments re the lapwing.  If, as most now seem to agree 
>(I do), this bird in Maryland last week was of the 'northernmost' 
>population found in South America, then this is really not what I would 
>expect to be a vagrant source.  First, the bird is clearly an adult, not a 
>bird of less than 12 months age.  Adults are very rarely found to be 
>vagrants of such an extreme as would be this case (even to Florida, if 
>this is the same bird).  Juveniles are always the most likely.  Second, 
>source populations for vagrants must also have some natural inclination to 
>at least partially migrate with the changing seasons.  The cayensis 
>population is not going to have such inclinations.  (In fact, in some 45 
>years studying banding records as a biologist for FWS, etc., I am not 
>aware of any tropical species of bird that has regular migrations beyond 
>movements to follow rains, etc.--e.g., weavers in Africa.)
>
>Lapwings in the tropics have no need to migrate....only local movements 
>that might be measured in several dozens of miles or so.  Only the most 
>southern populations should have this inclination to escape the colder 
>months of southernmost Chile and Argentina.  If a cayensis lapwing found 
>itself in Florida or Maryland, it likely would have zero idea of where it 
>is relative to its 'home'...so it is very likely to just sit...and hope 
>for a mate to find it, etc., unless cold weather really stresses it to do 
>something.  Range expansions of any bird population can be measured at 
>about 2-3 times the average dispersal distance of the juveniles from their 
>natal territory.  So if the juveniles average maybe 25 miles from natal 
>territory to first nesting territory, then range expansion into suitable 
>habitats might approach 50+ miles every year or three with a superabundant 
>number of surviving juveniles.  I cannot imagine the cayensis lapwing 
>having major expansions over a decade that would cause an adult to appear 
>anywhere in the US.....until there are birds nesting in Cuba or just south 
>of Brownsville, Texas....
>
>Not withstanding all of the above, I think it is possible for such a 
>lapwing to have gotten to the US.  Last year was very stormy, to say the 
>least.  Four major hurricanes struck Florida alone.  A juvenile somewhere 
>in the Caribbean may have been further sucked and blown to Florida last 
>year.  Once there, it had no idea of how to 'return' to South 
>America...even which way is actually "south" would be a problem for 
>it.  So it could have sat in northern Florida for the past 6-9 months, 
>molted, and then got caught up in Alberto.  My view of the photos were 
>that it was in fresh plumage...no molt in evidence, etc.  What we need are 
>some opinions from the Florida observers if the photos Mark Hoffman took 
>last weekend appear to be the same bird.
>
>My guess is that it could now be almost anywhere on the Delmarva....and 
>once found may settle in for the rest of the summer, at least.  AND there 
>are more than a few places....a needle in a very large hay stack!
>
>Keep looking folks!  Unless a local peregrine grabbed it, it should be 
>somewhere.....???
>
>Jay
>
>
>Jay M. Sheppard
>Managing Editor and Historical Data Coordinator
>Ornithological Worldwide Literature (OWL)
>www.BIRDLIT.ORG/OWL
>Laurel, MD
>
>
>In a message dated 6/23/2006 10:03:13 AM Eastern Daylight Time, 
> writes:
>
>
>
>
>Folks
>
>   I don't have any reason to think it is a captive escapee; however point 2
>is a bit misleading. The northern form, cayennensis is extremely common in
>northern South America and ranges south into Brazil. So its range is
>actually pretty large, and includes all of Venezuela. It is by no means a
>small and restricted range. If there are Southern Lapwings in captivity it
>would be interesting to find out what subspecies they belong to though.
>
>Al
>
>Alvaro Jaramillo
>Biologist
>San Francisco Bay Bird Observatory
>P.O. Box 247
>Alviso, CA 95002
>http://www.sfbbo.org
>

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Phil Davis      Davidsonville, Maryland     USA
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