Erie Bird Observatory

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Thrush I.D.

I caught this Gray-cheeked Thrush earlier today.




It was the sixth and final thrush species I expect to band this spring (Varied and Bicknell's would be nice but are highly improbable). Since I've photographed at least one individual of each species I've banded so far, I thought it'd be fun to take a look at this group and show the main differences between the species and when to expect them in NW Pennsylvania.


The easiest way is to check your calendar. The only species you're likely to see year-round is American Robin. It's everywhere, has yellow bill, dark head and rusty underparts. The juveniles are spotted, but only for a short time in summer.



If you see a thrush with a spotted chest during the winter months (November-March), it's almost guaranteed to be a Hermit Thrush. Look for the contrast between the rusty tail and brownish back

Tail-Back contrast in direct sunlight
Tail-Back contrast under cloudy conditions
It also has a compete pale eye-ring.



As you can see from the above photos, lighting makes a big difference in how the bird looks, but the relative size of the eye-ring remains the same.

Most Hermit Thrushes are gone by the end of April. I banded my last one on 4 May and don't expect to see any more this spring.

The next thrush to arrive is usually the Wood Thrush. It shows up in let April and breeds in our area. Wood Thrush are much larger than the other spot-breasted species, but also very brightly colored and with distinctive black spotting on its breast.


Its large size, reddish-brown back and boldly spotted underparts set it apart from the others.

After that, things get a little trickier. The remaining three species, Veery, Swainson's Ihrush and Gray-cheeked Thrush can be difficult to tell apart. All three arrive in May, but only the Veery stays to breed.

The easiest way to separate them is by comparing their facial patterns.

Swainson's Thrush has a bold yellowish eye-ring, yellowish super cilium above the lores and a yellowish wash on its throat.


Veery has an indistinct eye-ring set on a rusty brown to brown face. There's no yellow or pale areas that stand out.

This photo is a bit more indicative of what you'll see in the field. Veeries aren't often seen in direct sunlight, preferring to stay in shaded forests.

In addition, Veeries have few spots on their chest, and the spots are indistinct.


Compare to the Swainson's Thrush, where the spots are distinct and set on a yellowish background.


And finally, the Gray-cheeked Thrush. It has an indistinct eye-ring set on a pale face with no yellowish or rusty tint.


The spots on its chest tend to be darker than what you see on a Swainson's, with no yellowish tinge at all. In fact, many authors refer to how "cold" this species appears in comparison to the others.


So now that you've read this, you shouldn't have any problem identifying our local thrushes. The only problem is that they skulk in the forest understory and tend to freeze when you're looking for them. The easiest way to observe them is to walk a shaded path and scan far ahead. They're often feeding in the open but dart back into cover when you get within 50 yds. A field scope helps.

Did we catch anything else this week? Absolutely.

Here are two of yesterday's and today's highlights.

Female Hooded Warbler
Male Blackburnian Warbler