Mimicry in Vireos

I love that birding is always a learning experience. If you read the Frontiers of Bird ID mailing list, you may have seen the messages going back and forth regarding mimicry in vireos. Most of us know about mimicry in Mockingbirds, Thrashers, Catbirds, and even Starlings and Blue Jays. I had no idea that vireos were capable of any type of mimicry. Here is an excerpt:

Subject: vireo mimicry
Date: Sun, 13 May 2007 17:26:37 -0700

Tim Spahr's report of a Bell's Vireo song presumably coming from a Warbling Vireo is of interest; I did not run into this specific combination when reviewing vireo songs, so perhaps his will serve as the first known such event. But, what is known is that vireos are excellent mimics and frequently sing all or parts of other species' songs. I assume the songs they mimic are those from their breeding grounds, so it is interesting to ponder the above-mentioned overlap (and subsequent WAVI occurrence in MA on spring migration if it bred near a Bell's Vireo).

I know several examples of vireo mimicry (some of which are documented in BNA accounts, like Yellow-throated and Blue-headed accounts). From personal experience, my favorites are listening to Black-capped Vireos in Hill Country TX where, interspersed in their song are notes from, among others, Acadian Flycatcher, Western Scrub-Jay, etc. One can do the same with White-eyed Vireos; in an almost Mockingbird-fashion, listen to vireo songs and determine how many notes are coming from other species. OK, perhaps I need a life.

Matt Heindel
Carlsbad, CA

Very interesting indeed!

The Cornell Lab of Ornithology

We're back from our vacation in the Finger Lakes and Southern Adirondacks of NY. We planned to go to Canada, but that plan was thwarted when we realized we'd need to pay duty tax on all of the wine we had bought in the Finger Lakes region. Oh well. We changed plans and spent more time in the wine country.



One highlight of the trip for me was a visit to the famous Cornell Lab or Ornithology. All that I can say is, "WOW!" I need to live at this place. The building, a beautiful piece of architecture, is surrounded by Sapsucker Woods. The building itself sits next to a series of ponds and marshy habitat. The sides of the building facing the ponds are all glass with Swarovski scopes set up for visitors to use. There are also some feeders set up.



When you enter the building, you are greeted with amazing paintings of birds by famous artists like Alexander Wilson, John James Audubon, and Louis Agassiz-Fuertes. Sounds of the outdoors are pumped in through speakers. There's a really well-stocked gift shop sponsored by Wild Birds Unlimited. They have the full suite of Cornell Lab Audio CD's, tons of bird books, and lots of other great stuff. It was hard not to spend a fortune in there.



A small theater holds a collection of Fuertes artwork that blew me away. He is one of my favorite artists and to see actual paintings in person was memorable. I'm not sure if the ones pictured above are authentic, but there were several others there. They also have an extensive collection of books that Fuertes contributed to. Quite impressive! See below.



On the way upstairs, a glass case caught my eye. It held almost 100 preserved hummingbirds of different species. It was a very old collection from the 1860's that survived many journeys around South America and the US and finally ended up as a donation to the lab. It was something spectacular to see - from the tiny White-bellied Emerald to the Sword-billed Hummingbird to the huge Violet Sabrewing.



The second floor houses many offices and cubicles for people doing work for the good of the birds. Where do I sign up for a job? The second floor also has a humongous ornithological library that I could have spent years browsing through. I walked through it for a few minutes and tried to soak in all of the knowledge and work that had gone into the thousands of books held on those shelves.

And oh yeah... on my way downstairs I saw an Ivory-billed Woodpecker! I even got a picture to prove it. All of those people looking down south are way off!

15 New North American Bird Species?

A recent article discussed how genetic tests have revealed up to 15 possible "splits" in birds in Canada and the US. These birds include Northern Fulmar, Solitary Sandpiper, Western Screech Owl, Warbling Vireo, Mexican Jay, Western Scrub-Jay, Common Raven, Mountain Chickadee, Bushtit, Winter Wren, Marsh Wren, Bewick's Wren, Hermit Thrush, Curve Billed Thrasher and Eastern Meadowlark. The study stated that DNA diverged by at least 2.5% in different populations of these species, therefore indicating a species separation. Alternatively, they also mention that some species that are currently viewed as separate species are not as genetically divergent: "The Snow Goose and Ross's Goose, for instance, shared 99.8 percent of DNA and the black-billed magpie and the yellow-billed magpie 99.6 percent. Gulls such as the Glaucous and Iceland Gulls were 99.8 percent the same."

So what does this mean to us as birders? The article doesn't state what the AOU's views are on this or what will be done with the data from the study. Listers are probably ecstatic at the idea of getting some "easy ticks" on their lists if some of these species are split. My hope is that these genetic splits are across some type of definitive geographic boundary or that there are field marks that will make these populations easy to distinguish. I'm always open to an ID challenge, but I fear that our field guides will fill with lots of lookalike species that cross boundaries and make identification frustrating or impossible in the field. From a new birder's perspective, these ID challenges can be very overwhelming. On the flip side, I'm intrigued by these discoveries and anxious to see how this plays out. Your thoughts?