Saturday, September 18, 2010

Fall banding: Week #5 in review

This past week things picked up nicely, bringing us what we expect at this point in migration, a nice diversity and good numbers of birds. We missed a day and a half to rain, but banded 183 new birds and handled 31 recaptures, one of which was a Gray Catbird first banded in 2005. There were 37 species, including 15 species of warblers. We are already at or above our fall season average for Black-throated Blue, Blackpoll, Magnolia, and Nashville Warblers, and American Redstart. The most special warbler of the week was this great young male Hooded Warbler. It is the third ever banded for RRBO, and only the second fall record for Dearborn.

We banded two other unusual birds this week. The first was this dark, heavily marked form of the Veery, matching descriptions of the Newfoundland race. I've put up a page with more photos and information on Veery subspecies at the RRBO web site.

The other surprise was this European Goldfinch. RRBO has done a lot of research on this species. While not a first for Dearborn, it was interesting nonetheless. This individual was not a wild vagrant from Europe, but an escaped or released cage bird, and you can see more photos and read all about it at the RRBO web site.

We banded four species of vireos this week: Warbling, Red-eyed (we're already at our fall average), Philadelphia, and Blue-headed. I think Warbling Vireos look angry, while Philadelphia Vireos, like the one below, look "cute."

Blue-headed Vireos are one of my favorite species. We don't catch a lot of them, and they are just so handsome.

Actually, photographing any vireo is a challenge. They are all fuss and squirm. My general rule is that I only take a few quick shots of any bird I handle. If I can't get a good one, my loss. I don't have a lot of great vireo portraits because they are so uncooperative, most pictures end up like the next two.

We've been getting a lot of great samples for our study of what fruits birds eat in the fall at our site. This is the fourth year I've collected droppings from Catharus thrushes. I often find (in addition to the seeds, pulp, and berry skins I'm looking for) small hard parts of insects. Most often it is sections of millipedes, parts of beetles, and, frequently, ant heads. I guess thrushes aren't particular about the type of Hymenoptera they eat -- this head of an Eastern Yellowjacket (Vespula maculifrons) stared out at me from a sample provided by a Gray-cheeked Thrush.

Dana Wloch, one of my undergraduate research associates, is in charge of identifying and categorizing the samples from all other bird species. This is mostly robins and catbirds, but this week we've gotten samples from Rose-breasted Grosbeak and Red-eyed Vireos. Seems like yellowjackets are on the menu, as this head and a couple legs came from one of the vireos.

I've been asked how birds manage to eat bees and wasps without getting stung. Usually, they wipe the insect on a branch or the ground and get rid of the stinger. A more lengthy answer can be found in my February 2007 column in Birder's World magazine.

And another new bander has joined the team. Welcome to Sara Cole, a senior at Wayne State University. Here is Dana showing Sara how to age and sex her first bird, a Common Grackle.

It was a fun week. More birds coming up.

Saturday, September 11, 2010

Fall banding: Weeks 3 & 4 in review

Weeks 3 and 4 (August 29 to September 10) were nothing much to write home about. We banded 117 new birds and handled 27 recaptures of 23 species. Looking back on the first month, it seems to be shaping up to be an above-average season for House Wrens, Red-eyed Vireos, and American Redstarts.

How can anybody get tired of seeing an adult male redstart?

In the fall, you see many more female-plumaged redstarts than these gorgeous males. Some are adult females, many are young birds, both males and females. Male American Redstarts do not get their bold black-and-orange plumage until their second full molt (for birds born this year, that will take place next fall). Still, young male redstarts are often a little more orange than yellow and can sometimes be differentiated from the even duller females. The young male below was especially bright.

Although it's a little hard to see in the photo above, the uppertail coverts are also quite dark and they contrast with the grayer-colored back. The orange patches at the base of the wings

Meanwhile, in the young probable-female below, the patches are dull yellow, and so are the patches on the tail.

The tail-fanning is a characteristic behavior of this species, earning it the name "candelita," or "little flame" in some Latin American countries where it spends the winter.

Speaking of tails, Palm Warblers are beginning to come through.

Tail-pumping is a very distinctive trait of this species. They do not, however, do this in the hand.

And let's welcome our first new bander of the fall 2010 season, Carmen Volante. Carmen is a senior here at UM-D and is shown here on the left with one of our veteran banders Andy Dettling, and Dana Wloch, the undergraduate research associate in her second year of looking at robin and catbird diets.

The middle week in September coming up is often our best week for diversity of birds, especially warblers. We'll see what we come up with!

Tuesday, September 7, 2010

Friday, September 3, 2010

Web site announcement

First off, I am holding off on posting a banding summary for this week. The theme would have been "crickets." As in, that's about all that was out there this week. The return to summer temperatures with associated southerly winds and no cold fronts didn't move many migrants through. The oppressive heat makes for unsafe banding conditions when the sun hits the majority of my nets, so I wasn't open much during the week, and today it is raining. I'll do a two-week review at the end of next week, as this break in the weather should create much better conditions.

Last week, I posted a reminder that we are moving the RRBO web site. It should all be complete next week. In the meantime, you can still use this URL to access the current/old site:

To be on the safe side, use my long University address (jcraves AT umd DOT umich DOT edu) or gmail address (jac DOT rrbo AT gmail DOT com) to contact me. My jac AT rrbo DOT org may not work for a few days.