“The largest part of the common tern population has its breeding grounds on either Spirit or Hennepin Island,” said biologist Kelly Applegate. “They fly all the way from the Gulf to lay eggs here.”
Mille Lacs Band conservation officers Mike Taylor and Eric Hanneken teamed up with state DNR officer Mike North and biologists July 21 to take on the common tern hatch count and banding project. The group made a trip out to Hennepin Island to collect their data. An area is set aside for the terns to breed and mature on the island.
Officers Taylor and Hanneken remained on the boat, while the rest of the group jumped in the lake to get to the bird reserve.
When they arrived on the island, Applegate ran through the ground rules of the island: Don’t step on the eggs, and don’t wreck the fencing.
Next, Applegate went through the basic characteristics and facts about the terns. He said the eggs sit for 18 to 20 days before they are able to hatch. Then, 28 to 30 days after hatching, the terns become airborne.
While still adolescent, the terns stroll about on the gravel area set aside for their hatching or hide in between small rocks for protection from the ringbilled gull, their most common predator.
These young chicks are fed small fish, minnows and crayfish under four inches by their mothers. The mothers recognize their chicks’ cries and bring the food directly.
After the summer months, the young birds fly with the adults to the Gulf of Mexico. The younger terns will live a full year in the area before returning to Mille Lacs to breed.

After an introduction to the terns, the group began the study. Andy Boyd assisted Applegate in counting of the unhatched eggs. Ron Lucas of the Minnesota Audubon Society and his son, Lucas, helped North collect chicks for banding.
Applegate said the numbers seem to be up from that of last year. “It is a good year for the terns. The weather has been nice for them,” he said. “There hasn’t been to many big waves or cold nights to kill the young.”
While Applegate collected numbers, North began banding the chicks. “A total of 25 birds have been banded today,” said North.
About 180 birds had been banded for the year, which is up from a total of 29 all last year.
“The reason we are banding so many birds this year is because of the oil spill in the Gulf of Mexico,” said Applegate. “We want to track more terns and see where they end up. If they die, it could be a possible result of the oil spill.”
The group wants to be able to track more birds with a more efficient system. With more bands, birds may be easier to find and track.

Photo top right: Hennepin Island is the summer home and breeding grounds of common terns.

Photo middle left: Minnesota DNR biologist Mike North put a band on an adult tern with a bad wing.

Photo bottom right: Kelly Applegate and another team member banded a tern chick.

Photos by Ben Sam.

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