Monday, November 7, 2016

November 7, 2016

Captain Sam's 
Once again, it was a slow morning at Captain Sam’s with 17 new birds and 12 recaptures, comprised of 8 species.  The low numbers were likely due to the windy conditions that persisted throughout the morning and it is also just getting to be that time of year.  We had a few notable captures including a late Black-throated Blue Warbler and an American Robin. 

The best way to age American Robins this time of year is to look for the presence of a molt limit in the wing.  Similar to other members of the thrush family, American Robins tend to have molt limits in the greater coverts.  Often the inner greater coverts are replaced during their first prebasic molt creating a contrast between the retained juvenile outer greater coverts.  The photo below is of an American Robin that was aged as a hatch-year with a molt limit in the greater coverts.  This individual also replaced its carpal covert, first alula(A1) and a few tertials.      
American Robin (hatch-year)

The robin we banded today was aged as an after-hatch-year based on the absence of a molt limit.  The photo below shows that its wing was uniformly adult and lacked any contrast within or between feather groups.      
American Robin (after-hatch-year)
-Mattie    


Little Bear
Today out at Little Bear we had one of the slowest days we have had this year with 3 new birds and 7 recaptures and 4 species. Again our recaptures outnumber the new birds and we didn't get a single Yellow-rumped Warbler! We had to close up early due to the wind but on our last net round we had an exciting capture, a Sharp-shinned Hawk! It was a small hatch year male. We hope that in the coming days we will catch more birds and that the wind dies down.

Sharp-shinned Hawk (Hatch Year, Male)

SpeciesCaptain Sam'sLittle Bear
NewRecapsNewRecaps
Sharp-shinned Hawk
-
1
1
-
Ruby-crowned Kinglet
2
-
-
-
Hermit Thrush
-
1
1
-
American Robin
1
-
-
-
Gray Catbird
-
4
1
6
Northern Mockingbird
-
-
-
1
Black-throated Blue Warbler
1
-
-
-
Yellow-rumped Warbler (Myrtle)
10
3
-
-
Swamp Sparrow
3
-
-
-
Northern Cardinal
-
3
-
-




 Banding StatsCaptain Sam'sLittle BearTOTAL
# Birds Banded
17
3
20
# of Recaptures
12
7
19
# of Species
8
4
9
Effort (net-hours)
130.0
57.0
187.0
Capture Rate (birds/100 net-hours)
22.3
17.5
20.8
# of Nets
26
19
45


Banding Staff
Aaron Given (CS)
Blaine Carnes (LB)
Mattie VandenBoom (CS)
Alison Nevins (LB)
Col Lauzau (LB)
Michael Gamble (CS)
Michael Rodgers (LB)
Ryan Donnelly (CS)
Nancy Raginski (CS)



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