Friday, August 23, 2013

A Little Hint of Fall Migration

The north winds last night help bring in some migrants!  We banded 26 new birds and 7 recaptures of 14 different species. 

A good mix of neotropical warblers were banded including Prairie Warbler, American Redstart, Northern Waterthrush, Prothonotary Warbler, and the first Hooded Warbler of the season.    

We also banded the first Empidonax flycatchers of the season with two "Traill's" Flycatcher and one Acadian Flycatcher.  Willow and Alder Flycatchers are collectively know as "Traill's" Flycatchers when a positive identification cannot be made.  In the field the only way to separate Willow and Alder Flycatcher is by their call as they look nearly identical.  When the bird is in the hand, it is also extremely difficult separate and most cases they can only be identified as "Traill's".  Several very precise and tedious measurements are taken including the difference in length between the longest primary and the longest secondaries, the longest primary and p6, p6 and p10, p9 and p5, nares to tip of bill, bill width, and tail length.  Even after all of these measurements there is usually too much overlap between the two. 

"Traill's" Flycatcher (HY, sex unknown)



Acadian Flycatcher (AHY, sex unknown)
 
This time of year when the birds rarely vocalize, it is difficult to separate "Traill's" from Acadian Flycatchers in the field but it can be done in the hand using leg color.  "Traill's" have black legs and Acadian have gray legs as shown in the photo below. 

- Aaron


 
NEW BIRDS
2 Common Ground-Dove
1 Downy Woodpecker
2 "Traill's" Flycatcher
1 Acadian Flycatcher
1 Red-eyed Vireo
1 Brown Thrasher
1 Northern Mockingbird
4 Prairie Warbler
5 American Redstart
1 Prothonotary Warbler
1 Northern Waterthush
1 Hooded Warbler
5 Painted Bunting

RECAPTURES
1 Red-eyed Vireo
1 Northern Cardinal
5 Painted Bunting

BANDING STATS
# of Birds Banded:  26
# of Recaptures:  7
# of Species:  14
Effort:  124.0 net-hours
Capture Rate:  26.6 birds/100 net-hours
# of Nets:  20 

2 comments:

  1. Your blog and photos are wonderful. Thanks!

    ReplyDelete
  2. Thanks, Ruth! I'm glad you are enjoying it.

    ReplyDelete