Color Variation in House Finches

CAPTAIN SAMS

It was a slow day of banding out on the spit today with 14 new birds and 11 recaptures of only 5 species.  The most interesting bird of the day was the last bird that I captured - a male House Finch.  What made this bird unique was that it had orange coloration on the head, breast, and rump instead of the typical red coloration.  So what caused this?  When birds are molting their feathers, the pigments they ingest from their food are deposited in the feather.  Red, yellow, and orange colors are produced by carotenoid pigments.  There are several different types of carotenoids each responsible for producing a certain color.  When this bird was molting in late summer/early fall, the carotenoids that produces the normal red coloration was lacking it its food but high in the carotenoid(s) that produces orange and/or yellow.  This bird may not always be "orange".  Next year when it molts, if its food source is high in carotenoids that produce red colors in the feathers, he will be red.   

House Finch "orange" variant (hatch-year, male)

normal House Finch (hatch-year, male)

-Aaron

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

Species	Captain Sams		Little Bear
	New	Recaps	New	Recaps
Ruby-crowned Kinglet	1	-	-	-
Gray Catbird	2	4	-	-
Hermit Thrush	-	2	-	-
Swamp Sparrow	-	1	-	-
House Finch	1	-	-	-
Yellow-rumped Warbler (Myrtle)	10	4	-	-

Today's Banding Stats	Captain Sams	Little Bear	TOTAL
# Birds Banded	14	-	-
# of Recaptures	11	-	-
# of Species	5	-	-
Effort (net-hours)	182.4	-	-
Capture Rate (birds/100 net-hours)	13.7	-	-
# of Nets	32	-	-

2023 Fall Cumulative Banding Stats	Captain Sams	Little Bear	TOTAL
# Birds Banded	4,489	3,380	7,869
# of Recaptures	1,157	729	1,886
# of Species	85	86	100
Effort (net-hours)	15,638.85	9,293.95	24,932.8
Capture Rate (birds/100 net-hours)	36.1	44.2	39.1
# of Days	95	78	-

Banding Staff

Aaron Given (CS)