A Couple of Fisher Ladies.

Here's a quick shot from today:

Belted Kingfisher (Ceryle alcyon),
Gander Mountain Forest Preserve, Lake Co, IL  4/5/2014

These are two female Belted Kingfishers (Ceryle alcyon), having a dispute about who owns that stretch of the river. Kingfishers are normally quite camera shy, but when they're preoccupied with fighting, you can get lucky. Here's a closer shot of the winner:

Belted Kingfisher (Ceryle alcyon),
Gander Mountain Forest Preserve, Lake Co, IL  4/5/2014

Of course, youngsters are often brazen, or just stupid, and they'll allow things like this:

Belted Kingfisher (Ceryle alcyon),
Illinois Beach State Park, Lake Co, IL 6/19/2012 

You can tell this one's a youngster by the rufous invading the blue band across the chest.

Kingfishers are neat birds. As their name implies, they mostly eat fish, although they will take frogs, crayfish, and even small mammals, usually catching their prey by diving head-first into the water. While trying to spot prey, they will hover, head down, in one spot for several seconds. Add in their big-headed look and rattling call, and they almost resemble a wind-up toy!

I will often point out to my students that while we try to describe discrete ecosystems, especially when water is involved, those ecosystems actually interact a good deal. Sullivan, et al. found that the quality of streams in a Kingfisher's territory was a major determinant of their reproductive success. (1) (Although I don't know how they handled the non-random distribution of birds between territories -- more experienced birds are likely to select and successfully defend the best territories, and also to nest successfully.) Kelly found that the complexity of a stream's bed affected the choice of prey types by Kingfishers, essentially reducing the effects of the birds' preferences to reflect the availability of different prey. (2) Both of these papers looked at the effects of an aquatic ecosystem to a bird that is to some degree terrestrial. Steinmetz, et al. examined the effects of Kingfishers and egrets on fish communities, finding that they play major roles in determining the structure of those communities by acting as top predators. (3)

As humans, we seem to like drawing boundaries -- they appear to help us in living such social lives, particularly in larger, denser societies. But when we're doing ecology, we have to remember to look at those boundaries as our study species see them, which is often a very different thing.

(1) Sullivan, S. M. P., Watzin, M. C., & Hession, W. C. (2006). Differences in the reproductive ecology of belted kingfishers (Ceryle alcyon) across streams with varying geomorphology and habitat quality. Waterbirds, 29(3), 258-270.

(2) Kelly, J. F. (1996). Effects of substrate on prey use by belted kingfishers (Ceryle alcyon): a test of the prey abundance-availability assumption. Canadian journal of zoology, 74(4), 693-697.

(3) Steinmetz, J., Kohler, S. L., & Soluk, D. A. (2003). Birds are overlooked top predators in aquatic food webs. Ecology, 84(5), 1324-1328.