Running amok

Post date: Jun 27, 2014 1:33:30 PM

Our cultural idea of fledging equates leaving the nest with flight. We imagine a songbird in a tree, or a raptor on a cliffside: the young bird poised at the edge of the nest, ready to jump off into nothing.

For most seabirds, the process is not so immediate. There's actually a period of time after chicks leave the nest and before they can fly, something like the equivalent of high school in humans. The adults spend little time at the colony -- providing food for an adult-sized chick takes constant effort by both members of the breeding pair -- and the chicks aren't too interested in having them around. When adults arrive back with fish, they're mobbed by five or six neighbor chicks in addition to their own.

Stuffed chick after a big feeding

Between feedings the chicks roam the area unattended, fighting and interacting with one another. These days, most of the pelican productivity plots look something like this:

Shrub plot on Chester Island

Ground plot on Marker 52

It's not just the pelicans, either. The large, densely concentrated tern nesting colonies on Chester Island, which contained nearly 10,000 nests at census, are now empty of adults. Roving bands of chicks have spread out across the island, usually guarded by one or two adults, and we never know where we might come across one of these creches.

Royal Tern creche, Chester Island

As we continue to observe chick feeding rates and collect diet samples, we've noticed that feedings are much larger and much less frequent than earlier in the nesting season. Adolescent pelicans, apparently, will eat anything...

Huge mullet...

Huge seatrout...

Marker posts?

The big fish are definitely a positive thing to see, but sometimes the chicks' appetites get them in trouble. Last week, we removed a plastic water bottle from a chick's throat. We also freed a chick at one of the Galveston Bay colonies that had a piece of monofilament fishing line wrapped tightly around its leg.

Water bottle that had been swallowed by a pelican chick, Shamrock Island, TX

As with human high schoolers, pre-fledgeling pelicans must face down the dangers of growing up. It won't be long until the chicks that we've watched from the day they hatched fly off into a world where we can't follow them any longer, and where first-winter mortality can be as high as 80%. They have to learn to fly, to locate and catch prey, and to navigate anthropogenic threats. In the meantime, we can still keep an eye on them... for now.