Author Topic: Fall Migration 2014  (Read 1195 times)

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Offline The Peregrine Chick

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Fall Migration 2014
« on: August 01, 2014, 17:04 »
Yup, fall hawk watches has begun. 

Waggoner's Gap outside of Harrisburg, Pennsylvania has opened up & first day, 4 raptors: 1 broad-winged Hawk & 3 American Kestrels. 


Offline The Peregrine Chick

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Re: Fall Migration 2014
« Reply #1 on: August 01, 2014, 21:51 »
Nuts, Corpus Christi Texas just reported their first peregrine ... only bird reported today (their opening day).

Offline Kinderchick

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Re: Fall Migration 2014
« Reply #2 on: August 01, 2014, 23:21 »
What?! :o Fall migration already?! Seems like the birds just arrived!

Offline The Peregrine Chick

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Re: Fall Migration 2014
« Reply #3 on: August 04, 2014, 10:55 »
First birds to move are usually the Mississippi Kites ... in the first 3 days at Corpus Christi there have been 57 MIKIs ... that's out of a total of 63 raptor sightings.  Actually, both the Texas sites currently reporting show MIKIs.  Went back through my emails and the site at Veracruz was reporting Orchard Orioles, Least Flycatchers & Yellow Warblers already on migration south ...

We'll have to see if it really is the start or just some early starters ...

Offline The Peregrine Chick

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Re: Fall Migration 2014
« Reply #4 on: September 12, 2014, 21:51 »
Big day at one of the Veracruz, Mexico hawk migration sites ... at least for Mississippi Kites ... 15,591 over a 6.5 hour period.  That brings the total to just under 174,000 kites (70,755 in Aug and 102,968 so far in Sept) through that site since the site opened on August 20th.  The day with the highest count was August 29th with over 27,000 in a 10 hour period and there have been no days between August 20th and today that MIKIs have not been observed at this site.  Imagine having 174,000 peregrines ...  :o

Offline sparkster

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Re: Fall Migration 2014
« Reply #5 on: September 13, 2014, 09:02 »
Big day at one of the Veracruz, Mexico hawk migration sites ... at least for Mississippi Kites ... 15,591 over a 6.5 hour period.  That brings the total to just under 174,000 kites (70,755 in Aug and 102,968 so far in Sept) through that site since the site opened on August 20th.  The day with the highest count was August 29th with over 27,000 in a 10 hour period and there have been no days between August 20th and today that MIKIs have not been observed at this site.  Imagine having 174,000 peregrines ...  :o

That is an amazing number of birds of any kind! It would be especially wonderful to see that many peregrine falcons.  :-*

How, exactly, is an accurate count done? I just did a web search to learn more about the migration site and found a photo of a large number of birds in the sky, but how is it possible to determine the species and the number when there are so many at one time?  And are there territory issues, or is it not a problem because they are all flying through so, therefore, not in anyone's territory?   ???

Offline The Peregrine Chick

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Re: Fall Migration 2014
« Reply #6 on: September 14, 2014, 11:44 »
How, exactly, is an accurate count done? I just did a web search to learn more about the migration site and found a photo of a large number of birds in the sky, but how is it possible to determine the species and the number when there are so many at one time?  And are there territory issues, or is it not a problem because they are all flying through so, therefore, not in anyone's territory?   ???

The observers at these sites are a) very skilled at identifying birds as they fly by and b) very skilled at counting large numbers - which is a bit like cooking or maybe baking is a better analogy.  Everyone knows someone who doesn't measure when they bake/cook and their food always comes out head-and-shoulders above those of us who always measure.  For hawk site observers and for researchers doing surveys of species like waterfowl, you count out a set number of birds - 10, 25 whatever and then you use the physical amount of space those birds take up to let you quickly "count" the rest of a flock or kettle in the case of raptors.  And it is a surprisingly accurate way to count birds - the margin of error for experienced counters is very small, statistically irrelevant in fact.  So counting 15,000 MIKIs is a question of experience and technique.  And they get a fair whack of practice - Turkey Vultures and Broad-winged Hawks also tend to migrate in alarmingly large numbers.

And no, no territorial issues.  Territorial conflict is primarily a nesting issue - want territory to nest, have territory and am nesting or have pre-fledge age chicks on territory.  After that, the pressure is off for the most part.  Doesn't mean there aren't territorial spats outside of the nesting period, but raptors know they can't afford to get hurt so unless there is a real need to defend/offend, they don't.  And migrating birds aren't interested in territories or really anyone on territories, they are just going from point A to point B.  And migrating raptors aren't spread out over the landscape, they have very specific routes that make use of the land's topography to aid them in their travels, either by helping make them travel more efficiently thereby conserving energy and resources (ridges, coastlines) or ensuring abundant food resources (wetlands, sometimes urban areas) or safe havens for roosting or waiting out weather (urban areas, protected areas).  They are much more tolerant of others of their own species - we had 7 adult peregrines on a building one night during migration - and all but one was gone before dawn the next day and none of them were our resident birds and our resident birds were still around and paid no attention.  Bald eagles can be very territorial during the nesting season but they will congregate in large numbers on the wintering grounds.  And they will often be much more tolerant of other species on their travels, though they can still become lunch to something bigger and meaner - but that isn't territorial, that's just the hierarchy of predation.

Hope that answers a couple of your questions   :)

Offline The Peregrine Chick

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Re: Fall Migration 2014
« Reply #7 on: September 14, 2014, 11:49 »
Big day at one of the Veracruz, Mexico hawk migration sites ... at least for Mississippi Kites ... 15,591 over a 6.5 hour period.  That brings the total to just under 174,000 kites (70,755 in Aug and 102,968 so far in Sept) through that site since the site opened on August 20th.  The day with the highest count was August 29th with over 27,000 in a 10 hour period and there have been no days between August 20th and today that MIKIs have not been observed at this site.  Imagine having 174,000 peregrines ...  :o

Apologies folks, I was passing along some numbers to other folks and added things together I shouldn't have!!  MIKI total for the season up to and including September 12th is 102,968.  Haven't seen the numbers for the weekend yet, but will post when I do.

Interestingly, the total number of all raptor species going through the Cardel Veracruz site is only 103,208 - MIKIs do like to get an early start  :D

Offline sparkster

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Re: Fall Migration 2014
« Reply #8 on: September 14, 2014, 15:01 »
The observers at these sites are a) very skilled at identifying birds as they fly by and b) very skilled at counting large numbers - which is a bit like cooking or maybe baking is a better analogy.  Everyone knows someone who doesn't measure when they bake/cook and their food always comes out head-and-shoulders above those of us who always measure.  For hawk site observers and for researchers doing surveys of species like waterfowl, you count out a set number of birds - 10, 25 whatever and then you use the physical amount of space those birds take up to let you quickly "count" the rest of a flock or kettle in the case of raptors.  And it is a surprisingly accurate way to count birds - the margin of error for experienced counters is very small, statistically irrelevant in fact.  So counting 15,000 MIKIs is a question of experience and technique.  And they get a fair whack of practice - Turkey Vultures and Broad-winged Hawks also tend to migrate in alarmingly large numbers.

And no, no territorial issues.  Territorial conflict is primarily a nesting issue - want territory to nest, have territory and am nesting or have pre-fledge age chicks on territory.  After that, the pressure is off for the most part.  Doesn't mean there aren't territorial spats outside of the nesting period, but raptors know they can't afford to get hurt so unless there is a real need to defend/offend, they don't.  And migrating birds aren't interested in territories or really anyone on territories, they are just going from point A to point B.  And migrating raptors aren't spread out over the landscape, they have very specific routes that make use of the land's topography to aid them in their travels, either by helping make them travel more efficiently thereby conserving energy and resources (ridges, coastlines) or ensuring abundant food resources (wetlands, sometimes urban areas) or safe havens for roosting or waiting out weather (urban areas, protected areas).  They are much more tolerant of others of their own species - we had 7 adult peregrines on a building one night during migration - and all but one was gone before dawn the next day and none of them were our resident birds and our resident birds were still around and paid no attention.  Bald eagles can be very territorial during the nesting season but they will congregate in large numbers on the wintering grounds.  And they will often be much more tolerant of other species on their travels, though they can still become lunch to something bigger and meaner - but that isn't territorial, that's just the hierarchy of predation.

Hope that answers a couple of your questions   :)

Thank you, TPC, for taking the time to answer my questions. I appreciate the information.

Offline The Peregrine Chick

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Re: Fall Migration 2014
« Reply #9 on: September 16, 2014, 17:20 »
More than the Mississippi Kites are moving in numbers, yesterday (Sept 15th) 10,387 Broad-winged Hawks went through Corpus Christi in 9.5 hours.

Offline des

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Re: Fall Migration 2014
« Reply #10 on: September 17, 2014, 11:13 »
How, exactly, is an accurate count done? I just did a web search to learn more about the migration site and found a photo of a large number of birds in the sky, but how is it possible to determine the species and the number when there are so many at one time?  And are there territory issues, or is it not a problem because they are all flying through so, therefore, not in anyone's territory?   ???

The observers at these sites are a) very skilled at identifying birds as they fly by and b) very skilled at counting large numbers - which is a bit like cooking or maybe baking is a better analogy.  Everyone knows someone who doesn't measure when they bake/cook and their food always comes out head-and-shoulders above those of us who always measure.  For hawk site observers and for researchers doing surveys of species like waterfowl, you count out a set number of birds - 10, 25 whatever and then you use the physical amount of space those birds take up to let you quickly "count" the rest of a flock or kettle in the case of raptors.  And it is a surprisingly accurate way to count birds - the margin of error for experienced counters is very small, statistically irrelevant in fact.  So counting 15,000 MIKIs is a question of experience and technique.  And they get a fair whack of practice - Turkey Vultures and Broad-winged Hawks also tend to migrate in alarmingly large numbers.

And no, no territorial issues.  Territorial conflict is primarily a nesting issue - want territory to nest, have territory and am nesting or have pre-fledge age chicks on territory.  After that, the pressure is off for the most part.  Doesn't mean there aren't territorial spats outside of the nesting period, but raptors know they can't afford to get hurt so unless there is a real need to defend/offend, they don't.  And migrating birds aren't interested in territories or really anyone on territories, they are just going from point A to point B.  And migrating raptors aren't spread out over the landscape, they have very specific routes that make use of the land's topography to aid them in their travels, either by helping make them travel more efficiently thereby conserving energy and resources (ridges, coastlines) or ensuring abundant food resources (wetlands, sometimes urban areas) or safe havens for roosting or waiting out weather (urban areas, protected areas).  They are much more tolerant of others of their own species - we had 7 adult peregrines on a building one night during migration - and all but one was gone before dawn the next day and none of them were our resident birds and our resident birds were still around and paid no attention.  Bald eagles can be very territorial during the nesting season but they will congregate in large numbers on the wintering grounds.  And they will often be much more tolerant of other species on their travels, though they can still become lunch to something bigger and meaner - but that isn't territorial, that's just the hierarchy of predation.

Hope that answers a couple of your questions   :)
So a kettle of raptors and a fine kettle of fish...lovely.  Thanks