Photos: Beluga whales beached near Anchorage

Two beluga whales were found freshly dead on mud flats just south of Anchorage's Kincaid Park on Monday night, though the cause of their deaths remains unknown.

Scientists from the National Marine Fisheries Service and the Alaska SeaLife Center spent Tuesday morning fighting a race against the fast-moving tide to perform a necropsy on a muddy beach about a mile from the park's motorcycle racing area in an effort to determine why the two female whales washed ashore.

The whales did not appear to have external injuries, according to Barb Mahoney, assistant stranding coordinator with National Marine Fisheries Service. Mud was packed into one whale's trachea, indicating it had been stranded alive.

Mahoney suspected the smaller whale, a 10-foot female, was at least 7 years old. The larger one, about 12 feet long, was tagged with a satellite tracker in 2002. Mahoney said once the whales' teeth are more closely examined, researchers will get a more accurate age.

It's relatively rare to see a dead beluga ashore in Cook Inlet. The endangered animals — there are an estimated 315 living in the Inlet — are often spotted swimming through the silty-gray waters of Knik and Turnagain arms. A few beached whales are found every year, the last one near the Turnagain Arm community of Hope in October 2013.

But if one of the animals were to wash ashore, marine biologists Lisanne Aerts and Bill Streever would be among the best people to find it.

That's what happened Monday night when the couple spotted the dead whales about three-quarters of a mile apart while walking along sandy bluffs near the Kincaid Park sand dunes that overlook the Anchorage Coastal Wildlife Refuge.

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