Tuesday, September 7, 2021

A Taste of Migration

 Captain Sam's:

Hatch-year Veery. This bird had a molt limit in the greater coverts, indicating it was born this year and undergoing just a partial molt during its first cycle. Photo by Ben Stalheim

Captain Sam's was begrudgingly slow. The 'veery' first bird I plucked from the net was a hatch-year Veery. This made me ecstatic for the rest of the day, but the humidity, heat, and wind seem to still be thwarting off migration here. We found some more migrants throughout the day such as the usual Common Yellowthroats, Prairie Warblers, and White-eyed Vireos. However, the day was equally dominated by recaptures, mainly of Downy Woodpeckers. In one check, we caught a hatch-year and after-hatch-year female Downy Woodpeckers. This gave us an opportunity to compare how these birds look in varying molt cycles. For the hatch-year, we noticed completely retained juvenile primary coverts. These were really brown and frail and contrasted noticeably with the fresher, blacker, and newer-looking greater coverts. However, in the adult female, we were able to age it as a second-year because there was a molt limit within the primary coverts. The bird had replaced some outer primary coverts and 1-2 inner primary coverts, but left a block of retained coverts that were dirty brown similar to the hatch-year bird. Because of the replacement of some, but not all primary coverts, we can age the bird as a second-year individual. These two were likely mother and daughter as they were caught side by side and immediately regrouped after we banded them. Oh and the adult female had a brood patch, indicating she had indeed bred this year. Pretty cool!

Hatch-year Female Downy Woodpecker. The primary coverts, those covering the long flight feathers furthest from the body are much browner and older than the ones to the left. This is a molt limit we look for in aging this species. Photo by Josh Lefever.

There is optimism that a cold front coming in this weekend will bring with it some heavy bird days, but we will have to wait and see. You never know what will end up in the nets, or simply fly over on a given day. With the NFC bucket/microphone up and running, I'm really excited to learn and decipher the nocturnal migrants that seemingly go undetected through this area. 

-Ben

Little Bear:

Today at Little Bear we were lucky to have a busier than anticipated first net check, with a couple cool birds which made the muggy weather a little bit more tolerable. Along with 2 more Eastern Kingbirds (we're catching a lot of them this year!), we also caught a Louisiana Waterthrush (aka LOWA). The Little Bear site only caught its first ever LOWA last year, so I was a bit surprised and very excited to see another one in a net this morning. 2021 is now the first year that a LOWA has been caught at both of KIBS' banding sites in the same season. 

Louisiana Waterthrush
Louisiana Waterthrushes are an early migrant, and we were pretty lucky to get this late moving hatch-year bird a week into September. We also caught the more common Northern Waterthrush during the same round, and took an obligatory side-by-side picture.
Louisiana Waterthrush (left) and Northern Waterthrush (right)
photo by Nate Watkins
These two species are actually both warblers, but earned their 'waterthrush' moniker because of their brown plumage and habit of foraging on the ground in dark and moist areas, which is more reminiscent of thrushes than their taxonomic kinfolk who are more often found flashing bright colors from high up in the tree tops. For a more in-depth explanation of the differences between these 2 similar species, check out one of our previous blog posts HERE.

-Josh

  Species  Captain Sam'sLittle Bear
NewRecapsNewRecaps
Downy Woodpecker
12--
Eastern Kingbird
--2-
White-eyed Vireo
1---
Red-eyed Vireo
--1-
Veery
1---
Ovenbird
-1--
Louisiana Waterthrush
--1-
Northern Waterthrush
--1-
Black-and-white Warbler
--1-
Common Yellowthroat
214-
Yellow Warbler
--1-
Prairie Warbler
1-1-
Northern Cardinal
-1-2
Painted Bunting
1-2-



Today's Banding StatsCaptain Sam'sLittle BearTOTAL
# Birds Banded
7
14
21
# of Recaptures
5
2
7
# of Species
8
10
14
Effort (net-hours)
127.5
108.1
235.6
Capture Rate (birds/100 net-hours)
9.4
14.8
11.9
# of Nets
30
23
53


2021 Fall Cumulative Banding Stats Captain Sam'sLittle BearTOTAL
# Birds Banded
445
278
723
# of Recaptures
128
50
178
# of Species
38
33
44
Effort (net-hours)
3091.5
1755.1
4846.6
Capture Rate (birds/100 net-hours)
18.5
18.7
18.6
# of Days2318-

Banding Staff

Aaron Given (CS)
Kristin Attinger (CS)
Kandace Glanville (CS)
Ben Stalheim (CS)
Nate Watkins (LB)
Josh Lefever (LB)

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