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House Finch |
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| Order Passeriformes
Family Fringillidae |
Alpha Code HOFI
AOU# 519.0
Band size(s): 1B - 1 - (1C) |
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| The
House Finch is one of the great generalists in the bird world.
Native to the western states, I have banded individuals in diverse areas
ranging from my backyard in greater Los Angeles to area deep in
the open deserts. Even in our chaparral habitat banding station,
it is the 5th most common bird we encounter. An interesting aside
is that in urban Los Angeles, its primary competitor is the slightly
larger House Sparrow (Passer domesticus). We have never caught a
HOSP at our chaparral station. House Finches seem to love feeding
stations and love to nest near human habitation. Even in the
deserts, they seem to congregate at even the smallest two building
towns. If there is no surface water, I have seen them move in
large flocks daily to springs and other water sources.
Natural History: House Finches have been documented for some spectacular population changes. Once found only in the West, it was introduced into New York in 1940. The population exploded and soon became as common in the East as it was in the West. Now we are seeing a dramatic decline in this bird. Male HOFIs have red across the head (though top is brown), on the throat and breast, and on the rump. The red can vary into oranges and yellows, which is apparently due to dietary deficiencies. The red is brighter in breeding season and duller in winter. Females and juvs. lack red and are streaked brown overall.
AHY-Me. Note extensive red vs HY- M below. One must always be aware of an occasional Purple or Cassin's Finch. In general, HOFIs are found from sea level to 2000 m, PUFI at mid elevations, and CAFIs at higher elevations. Over the last seven years at Zuma Canyon at almost sea level, we have encountered 12 PUFI vs 384 HOFI. At a station I band at 1500 m, we encounter HOFI and PUFI about 50:50. I have never encountered a CAFI, so my comments are mostly restricted to HOFI vs PUFI. First, Purple Finches are not purple; National Geographics says "rose red." Next, the red in HOFI is localized, while in PUFI it is more diffused across the body. The undertail covs are streaked in HOFI but usually plain in PUFI. Others note that the auricular is not well defined in HOFI, while the whitish eyebrow & moustachial makes the auricular more obvious in PUFI. The tail is squared in HOFI and notched in PUFI. Female HOFI are brownish, but female have a greenish sheen to them when looked at in sunlight. Peter Pyle, in his ID Guide to North American birds, almost never uses behavior as a characteristic, but this is one place where he does. HOFI almost never bites, while PUFI tend to bite when being taken out of the net When released, HOFI typically gives a call, while PUFI do not. Of course, the next time your bird will break these behavioral rules! |
Diseases - House
Finches have become infected with several diseases that have hit the
news. In the East, birds have been found with Mycoplasmal
conjunctivitis. The bacterial disease is recognized by the eyes
becoming pussy, red, and swollen. The disease is presently
restricted to the Eastern population. The birds' habit of
congregating at feeders may be a major method of transmission. The
lead in studying this disease has been Cornell
Lab of Ornithology; go there for further information.
House Finches in the West occasionally have what is called "bumblefoot." It is a catchall description of lameness in birds, but what I have seen is missing toes and wart-like growths on the foot. There seems to be many causes, but for passerines I see it more in urban birds that are on asphalt (Brewer's Blackbirds and House Finches) than in these same birds in non-urban settings. WARNING: In both cases, the bird banding protocol is to isolate the bird bag after use to be washed, and for the bander to wash his/her hands after processing the bird. Probably, all tools (ruler, pliers, etc) should have a quick dose of rubbing alcohol. Banding - Especially fledging, HOFIs are often found in loose flocks of 5-50+ birds, so we often catch them in bunches. They are relatively easy to take out of the nets. Sexing - Most HY/SY birds can be sexed starting about July onward, although some adult females have tinges of color. However, HY/SY birds without red may be difficult to separate from AHY females, if there are difficulties in ageing.
AHY-F above. Ageing - In males, the size of the red rump patch is sometimes helpful, although there is quite a bit of overlap. Pyle states "the 1st PB is quite variable" so looking at molt limits and such is very tricky.
HY-M - note reduced red as compared to AHY-M above. Note brown in central crown typical of HOFI (vs PUFI). |
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