Researchers say the stranding of nearly a dozen whales on Maui in August might have been caused by a calf that had pneumonia and died. Four of the whales had to be euthanized.
Scientists say the whales are extremely social animals, and tend to those that are sick and strand themselves.
The mass stranding of 11 pygmy killer whales occurred August 29 at Sugar Beach on Maui’s south shore. Initially they were thought to be melon headed whales.One was a calf that washed ashore alive, but later died.
“We do have some preliminary results, specifically to the calf in this group, and we have confirmed that the calf was sick with pneumonia. So it was struggling with a significant respiratory infection,” said Dr. Kristi West, HPU Biology professor.
They say some of the other whales might have also been infected. They’re still waiting for the results. Scientists say pygmy killer whales are highly social animals that like to travel in groups and often tend to sick members.
“So you can in mass stranding situations have a few small number of sick animals that come ashore and then healthier animals that are part of their social group will just follow them ashore. So it’s very sad,” said David Schofield, NOAA Marine Animal Response Coordinator.
Researchers say when they examined the other whales at the time of the stranding, the animals were in shock and stressed but showed no signs of illness or injury. So researchers decided to release them back out at sea.
“Our plan was to release in stages. We were gonna pick the stronger animals, which happened to be a group of six animals and do a first phase release,” said Dr. Greg Levine, NOAA contract veterinarian.
But within 15 minutes, the whales returned and had to be pushed back out several times. A large tiger shark also swam to the area and scientists say they then had to make a difficult decision.
“The apparent failure of the group and imminent possible restranding of the group and the fact there was a large shark in the area. We determined the best course of action was to humanely euthanize those four animals on the beach,” said Dr. Levine.
Officials say the other animals also had empty stomachs, indicating they had not eaten in a few days. That also may point towards signs of illness.