Scientists suspect infection or disease may be why two pygmy whales stranded themselves last week on Maui's Sugar Beach. The two male mammals were euthanized after blood samples indicated they likely could not have survived in the wild.
Kristi West, University of Hawaii assistant researcher, told reporters Tuesday that necropsies of the whales showed signs of illness similar to those of other whales that beached themselves in the same area in August.
"Both animals did have abnormal and inflammed lymph nodes which was similar to what we observed with the end of August event," West said.
"And this does suggest the animals were likely fighting some type of infection at the time of the stranding. And next steps are now underway, which involve the histopathology analysis phase and an intensive disease screening to better understand what was the cause."
West said it could take weeks or months before the tests are completed. The researchers also are testing ear samples for acoustic trauma, a process that could take as long as a year to finish.
The two mammals were in a group of six pygmy whales spotted lingering offshore in mid-September when the National Oceanic and Atmospheric Administration began monitoring them.
Two of the whales stranded themselves on Sept. 24 and were subsequently put down. The four remaining whales also appeared lethargic but grew more active, swimming farther from shore as the days went by.
David Schofield, NOAA's regional marine mammal stranding response coordinator, said it appears the four healthier mammals have moved back to sea. They were last sighted on Sept. 28. But volunteers are continuing to monitor the area in the event there are more sightings.
In August, authorities sedated and euthansized four whales after 10 stranded on Sugar Beach. The remaining six whales were floated back to the ocean. One calf also died nearby, and was later found to have been suffering from pneumonia.