For the Birds Radio Program: Sea Swallows

Original Air Date: June 30, 1986

Laura provides some information about Duluth’s nesting colony of Common Terns as well as some bad puns.

Duration: 3′30″


(Recording of a Common Tern).

When most Duluthians see a large whitish bird flying along the lake, they immediately call it a “seagull.” Serious birders are offended by this carelessness–our gulls are a thousand miles from the nearest sea and are properly called the Herring Gull and the Ring-billed Gull. But, even more important, many of those whitish birds following the shore are not gulls at all–they’re terns.

The Common Tern is nicknamed the sea swallow for its strikingly graceful flight. Its plumage is beautiful as well. Like its larger relatives the gulls, it has a white breast and a soft gray mantle. But, unlike gulls, the Common Tern’s feet and bill are blood-red, and it has a handsome black cap. Its wings are extremely slender and pointed, and its tail is sharply forked.

You won’t find a Common Tern eating garbage at the dump, or mooching for french fries at Canal Park. No, it is almost exclusively a fish eater–and its technique is impeccable. It flies alone along the shoreline, head and beak pointed down. When it spots a school of fish, it hovers a moment, then suddenly plunges like a winged arrow straight into the water and snaps up a fish in its sharp beak. It’s hardly a competitor with human fishermen–adult terns weigh only about 4-1/2 ounces, so they can’t handle fish longer than three or four inches.

The nesting colony in Duluth has traditionally been located in the Port Terminal, near UPS. But not one chick has survived there in years, and so the DNR non-game program is funding a research biologist, Tom Davis, to relocate the colony to the harbor islands.

Controlled burning and brushing on Herding Island, Interstate Island, and Barker’s Island have restored beach areas for the terns’ ground nests, and now owl decoys at the Port Terminal are set up to shoo the birds over to the islands. Up until a couple of weeks ago, about 30 were spending their time at Interstate Island, and somewhere around 50- 100 birds are currently spending their time at Herding Island–it’s hard to get more precise estimates because the research has to be done at a distance–the birds are very skittish in this new, unfamiliar area.

It’s important to attract as many terns as possible to the islands–proper nesting behavior may be inhibited unless there are large numbers of these gregarious birds, and, because they nest in the open on the ground, their security from predators also depends on high numbers. They aggressively defend their nests–countless sadder but wiser birders and picnickers have shed blood near tern colonies.

Tern chicks are helpless when they hatch and need to be fed by their parents. The adults, which probably mate for life, share the responsibilities of child-rearing equitably, tirelessly stuffing fish, head-first, into their tiny chicks’ mouths. It’s not unusual to see a baby tern gulping away at a fish longer than itself, the tail sticking out of its mouth even as it sits, immobilized, digesting the head.

You could think of large tern colonies as fraTERNities, unless your tern of mind makes a sudden ternabout at that tern of phrase.

This is Laura Erickson, this program has been “For the Birds,” and we’ve now reached the point of no reTern.

(Recording of a Common Tern)