A crush of whales has caused Glacier Bay National Park to lower the cruise ship speed limit in parts of its waters. Only two of the big ships are allowed inside the bay at any one time, and now they must not exceed 10 knots (11.5 mph) in "whale zones" – areas where large numbers of whales gather.
Large cruise ships must also carry a staffer from the National Park Service on board while traversing the zones.
The new limit is just 3 knots slower than the previous top-end speed, but the National Parks Service said it will greatly reduce the risk of a collision with humpback whales that can weigh in excess of 45 tons.
Glacier Bay and nearby Icy Straits – about 530 miles southeast of Anchorage -- are a favorite summer feeding ground for more than 100 of the large marine mammals that travel up to 16,000 miles a year from the Bering Sea to Hawaii, California and Mexico.
Crowd of 60 humpbacks
Parks officials say up to a third of all Southeast Alaska humpbacks stop in Glacier Bay. They arrive in June and leave for warmer waters in late October and early November.
But this year, the whales are concentrated in unusually large numbers at the mouth of the Bay, between Point Carolus and Willoughby Island. That's the narrowest section of Glacier Bay.
"There are consistently 60 or so whales there. Usually, we would see between 10 and 20 of them in that area," said Tom Vandenberg, Glacier Bay's Chief Interpretive Officer.
Glacier Bay Rangers believe the whales are following huge schools of capelin – an oily smelt that is high in calories and a favored whale food.
Vandenberg was near the area on Wednesday, and said the humpbacks put on quite a show.
"I was fishing, and you could constantly hear them blowing -- and see them breaching and slapping their tails," Vandenberg said.
Last collision in 2005
Vandenberg added that the ships in Glacier Bay do a relatively good job of keeping their distance from the whales. The last collision with one of them came in 2005, when a humpback calf was struck and killed. Four years earlier, a large female, known as #68, and also called "Snow" -- a constant visitor to the Bay since 1976 -- was struck and killed by a passing cruise ship. Such smaller vessels as day-cruise boats, kayaks, and small motorboats are not restricted inside the bay, and sometimes get close to the animals, but generally, pose little threat to the big whales.
"We had it in storage for some time and tried to clean the oil from the bones to put the skeleton together, and quickly realized it was a job that was way too big for us to handle," said Vandenberg.
A special display area is being built at the Glacier Bay Park headquarters in Bartlett Cove, where the 50-foot-long exhibit will go on display in the spring of 2013.
Glacier Bay National Park sees an average of 500,000 visitors a year – most coming by cruise ships. The area's glaciers and whales are top attractions.
Contact Sean Doogan at sean(at)alaskadispatch.com