Last Minute Worm-eating Warbler at Little Bear!

 CAPTAIN SAMS

September has brought cooler weather but we’re still waiting for a push of migrants. That being said, we’re still enjoying the usual suspects like American Redstarts and Prairie Warblers. Today we also caught an interesting Northern Waterthrush, one with some leucistic feathers! Waterthrushes typically have dark brown feathers on their wings, head, and back but this one had a single white greater covert, a band of white feathers across its rump, and a single white feather above its eye! Leucism is a partial loss of pigment caused by a genetic mutation which inhibits an individual’s ability to produce melanin. This is seen in a wide variety of animals including reptiles, mammals, and many species of birds!  

A Northern Waterthrush with a band
of leucistic feathers on its rump

A Northern Waterthrush with a
white feather above its eye 

LITTLE BEAR

Had an interesting day out at Little Bear with modest numbers, but great species diversity. Of the eleven species we had at Little Bear three, an Eastern Kingbird, a Wilson's Warbler, and a Worm-eating Warbler were all first-of-seasons! 

After Hatch Year Worm-eating Warbler

Worm-eating Warblers are olive-backed with buffy faces sporting distinctive broad, dark brown crown stripes. Many warblers are associated with foraging behaviors in live leaves high in the canopy, but Worm-eating Warblers have a particular reputation for foraging in twisted, dead leaves, often close to the understory, for invertebrates. While they do make use of this foraging strategy on the breeding grounds it is actually something that is practiced far more on their wintering grounds in the Caribbean and Central America, where this kind of foraging can be far and away the most common method depending on the month. While in the states they make ample use of live leaves, though are still often found near the ground.

Worm-eating Warblers are ground nesters and are, according to Hal. H. Harrison in his excellent book Wood Warbler World, to be held with the Virginia's Warbler as the most difficult nest to find. These are positioned like Black-and-White Warblers by some sort of larger substrate like a stump or rock on the forest floor, but are "buried in a drift of leaves" that makes the nest incredibly difficult to detect. The female does her part as well by refraining from flushing until almost stepped on. I think the strongest endorsement of the skill of the Worm-eating Warbler in concealing its nest is Mr. Harrison's admission that twenty-six years passed between his discovery of two nests despite serious effort and ample assistance.

While I don't know when (or if) I will see a Worm-eating Warbler's nest, I am grateful we decided to have one more run before close, giving us the chance to have seen this under-appreciated warbler today!

-Jeremiah

Species	Captain Sam's		Little Bear
	New	Recaps	New	Recaps
Mourning Dove	1	-	-	1
Eastern Kingbird	-	-	1	-
White-eyed Vireo	-	-	1	-
Carolina Wren	-	-	-	3
Ovenbird	-	-	1	-
Worm-eating Warbler	-	-	1	-
Northern Waterthrush	2	1	2	-
Common Yellowthroat	5	-	2	-
American Redstart	2	-	-	-
Yellow Warbler	1	-	-	-
Prairie Warbler	3	-	-	-
Wilson's Warbler	-	-	1	-
Northern Cardinal	1	-	-	3
Painted Bunting	3	2	3	1

Today's Banding Stats	Captain Sams	Little Bear	TOTAL
# Birds Banded	18	12	30
# of Recaptures	3	8	11
# of Species	8	11	14
Effort (net-hours)	134.7	100.5	235.2
Capture Rate (birds/100 net-hours)	15.6	19.9	17.4
# of Nets	32	21	53

2025 Fall Cumulative Banding Stats	Captain Sams	Little Bear	TOTAL
# Birds Banded	328	179	507
# of Recaptures	79	65	144
# of Species	30	26	37
Effort (net-hours)	2,379.45	1,112.75	3,492.2
Capture Rate (birds/100 net-hours)	17.1	21.9	18.64
# of Days	17	10

Banding Staff

Aaron Given (CS)

Michael Gamble (CS)

Liz Held (LB)

Arden Schneider (CS)

Camille Beckwith (LB)

Jeremiah Sullivan (LB)

Note:  All banding, marking, and sampling is being conducted under a federally authorized Bird Banding Permit issued by the U.S. Geological Survey’s Bird Banding Lab.