Fishing birds help each other at Market Lake

As I drove along the almost dry ponds of Market Lake Management Area, I noticed several great blue herons flying along the dike heading south. Then I saw a flock of eight double-crested cormorants as they appeared to be chasing small catfish in the deep water along the dike.

The cormorants spaced themselves about two feet from each other as they swam, then dove in unison. When they surfaced, several of them usually had a small catfish or chub in their bill. The chubs were easy for the birds to quickly position the meal and swallow them head-first. The catfish were a different story; with their spines just behind their head, they made it hard for the cormorants to swallow.

When one of the adult cormorants captured a catfish, young cormorants followed the adults, begging to be given their brunch. Sometimes the stunned or killed fish would be given to a young bird to work on as the rest of the flock continued hunting the deep water.

If the cormorants came to a patch of water weeds, they would get out of the picket line and hunt for hiding fish in the weeds. The herons would get into the shallow edge of the pools near the patches of weeds and pick off the fish trying to escape. Each time a heron would attempt to capture a fish in the shallows, they were usually successful, but if they attempted to harvest one in the deeper water, they were unsuccessful.

Once a heron captured a fish, it appeared to be off limits to the other herons. These birds fought and jockeyed for position around the patches of the weeds. I did not observe any of the adult herons helping the young ones to capture their fish. I did watch one young heron that captured a small catfish, and it worked on it for 20 minutes before it was able to pull off the sharpies and swallow the fish. Even the adult herons had difficulty getting the catfish to go down their throat, whereas the chubs were gone in a flash.

After watching all this successful fishing for over an hour, a great egret flew in to join the fishing party. It captured a catfish, which was difficult to eat, but finally got it down. The next two fish captured by the egret were chubs and quickly became food. I did notice that the egret kept a healthy distance from the herons and moved away when it was approached by the larger birds.

Another photographer came by to chat.

“Boy, the herons and the egret really know how to benefit from the cormorants,” she commented. “They are fun to watch.”

As I was leaving Market Lake, four more great egrets with a snowy egret showed up, so I had to spend another hour watching them capture their lunch. It appears that the migration of these large birds has begun, and Market Lake is a great place to catch fish and fill their tummies of wiggling fish.

It also appears the water has been shut down to the ponds of Market Lake, leaving only the deep channels with water. The mud flats are dry, making most of the small shorebirds stop at other places. I saw a few killdeer and greater yellowlegs, but the show put on by the cormorants, egrets and great blue herons made it worth the time. It thrilled me to be able to watch and study them.