DETROIT (WWJ) – Test results have come back on hundreds of dead seagulls spotted along Jefferson Avenue in the Delray neighborhood near the Rouge River Bridge.

The Michigan Department of Natural Resources says the ring-billed gulls have chosen an area near the Waste Water Treatment Plant to nest, just off the Detroit River, so a larger number of the birds are in the area compared to previous years — about 10,000 compared to 5,000.

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Residents speculated that a number of young birds died because they couldn’t fly and were hit by passing traffic. But the DNS says no evidence of trauma was found on any of the birds during their testing.

Officials concluded that there seems to be competition for food and water resources between the adult and young ring-billed gulls. The adults view the younger gulls as competition, and often they peck at them until they die.

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The DNR has also ruled out any type of diseases, such as avian botulism, West Nile virus, avian influenza, pesticides and metals toxicity. Tissues were also submitted for microscope examination. While most of these tests are relatively quick, final results could take weeks.

The extreme heat over the past few days as well as the increased traffic on Jefferson Avenue because of the closure of southbound I-75 could also be contributing factors to the large number of bird deaths.

Many area groups are expressing interest in rescuing the birds, including the Detroit Audubon Society, Friends of the Rouge River and the Michigan Humane Society. “Nature area” signage has been added to the road, and the city is adding additional fencing to prevent the birds from coming onto the roadway.

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This species of birds is federally protected, so it is illegal to move the nests.