A humpback whale calf known as Tango that washed up dead near Auke Bay earlier this summer was killed by a large boat, according to the post-mortem exam.
The fatal injuries included deep lacerations on the calf’s body and pectoral fin, likely caused by a propeller. And according to NOAA marine mammal specialist Suzie Teerlink, Tango also had scarring from past injuries caused by smaller boats.
“This calf had interactions with several vessels during the course of its short life,” Teerlink said. “We see these sub-lethal interactions unfortunately pretty frequently.”
Tango was born this year to Sasha, a well-known whale that returns to the Juneau-area annually. Sasha herself is easily recognizable due to a distinct scar from entanglement in fishing gear.
“That’s I think a testament that they can survive lots of these human interactions,” Teerlink said. “But there’s a lot of risks out there.”
NOAA does not keep a formal record of vessel strikes or entanglement incidents in the region, but Teerlink said the area where Sasha and her calves tend to feed has high boat traffic. And she added that both the whale population and the number of boats in the Juneau area have been increasing in recent years, which could cause more injuries.
“There sometimes can be a misconception that whales know where boats are at all times,” Teerlink said. “They do pay attention to their surroundings. But you know, it’s not foolproof.”
Teerlink said the best way to keep whales safe is to reduce speeds. That gives whales more time to adjust and gives mariners more time to take a look around the area. NOAA guidelines also call for vessels to stay at least 100 yards away from whales.
Biologists are also examining the death of a sub-adult female humpback found near Kodiak Island Sept. 25, after a necropsy showed damage from a possible boat strike near her left eye.
