This story has been updated with additional information.
Two humpback whales appear to have been killed by ship strikes in Icy Strait this summer, including a yearling and a 23-year-old female that was pregnant, although the cause of death in the latter case is still under review, according to the National Oceanic and Atmospheric Administration.
There have also been several other reports this summer of vessels striking whales that do not appear to be related to the deaths, according to a report by the agency published Tuesday.
The incident confirmed as a likely ship strike was discovered July 3 when “NOAA Fisheries received a report of a floating humpback whale, which ultimately washed ashore near Elfin Cove,” the report states.
“Postmortem examination of this male humpback whale found injuries consistent with a vessel strike as the cause of death. Measurements collected indicate he was likely a yearling.”
The second humpback whale was reported floating near Point Adolphus on July 22, according to NOAA.
“This 23-year-old female was first spotted as a calf in 2001 and has a sighting history in Southeast Alaska and Hawaii,” the agency’s report notes. “The necropsy report is pending, but postmortem examination found SEAK-1731 was 48-feet long and was pregnant at the time of her death. While the necropsy team found evidence suggesting blunt force trauma from a possible vessel strike, the cause of death could not be confirmed at the time of the necropsy.”
Whale strikes by vessels, as well as entanglements with fishing and crab pot lines, are a provocative issue among many in Southeast Alaska, especially with cruise tourism surging to record levels last year. In late July of last year, NOAA officials reported three whales had been entangled in lines and two more struck by vessels during the preceding few weeks. In late August a vessel strike killed a local humpback whale calf named Tango near Juneau.
In early July of this year the National Park Service issued a vessel speed restriction in the eastern portion of Lower Glacier Bay until further notice due to a large number of whales feeding in the area. A record number of humpback calves have been documented in Glacier Bay this year, according to officials.
The report issued by NOAA this week states its stranding hotline has received “several reports of vessels colliding with humpback whales in the Icy Strait area this summer.”
“However, given when and where these reported vessel strikes occurred, it is unlikely they were linked to the two humpback whale strandings,” the report states.
The circumstances of the strikes and damage to the whales in the self-reported hotline incidents vary, said Mandy Keo, Alaska region stranding coordinator for NOAA, in an interview Friday.
“Not all vessel interactions are equal,” she said. “So some of them were vessels that were not moving and the whale kind of bumped into them while it was feeding. Others were more of what you probably think of — like a vessel in transit when it hits something or hits a whale in the area.”
NOAA officials follow up with people making hotline reports to see if significant injuries to whales or persons occurred, as well as other information about incidents, Keo said.
“In the large majority of these cases generally, especially the self-reported ones, they’re not doing anything malicious,” she said. “It was just an unexpected interaction with the whale. So use that as an opportunity to collect data about the incident.”
The NOAA report notes the following regulations apply to vessels approaching humpback whales:
• Not approaching within 100 yards of a humpback whale.
• Not placing a vessel in the path of oncoming humpback whales, causing them to surface within 100 yards of a vessel.
• Not disrupting the normal behavior or prior activity of a whale.
• Operating vessels at a slow, safe speed when near a humpback whale
