ANCHORAGE - It's a good summer for humpback whales cruising the chilly waters of Glacier Bay National Park and Preserve, and park rangers would like to keep it that way.
Park officials say a special area created earlier this summer to protect the whales from being struck by vessels that visit the 3.3-million-acre park - most of it water - is being extended, effective immediately.
Park superintendent Cherry Payne said during the past week at least four mother and calf pairs and 15 other humpback whales have been observed in the special whale waters area created in May.
Payne said it's not necessarily that there are more whales in the park this summer. It could just be they are congregating in different places in the bay than in previous years.
This summer, the whales have mostly been spotted along the shore at the western edge of the park entrance and near the entrance to the West Arm inside Glacier Bay. In previous years, the whales tended to stay in lower Glacier Bay.
Humpback whales, which can grow to 50 feet long and weigh more than 35 tons, tend to stay near the shoreline but can surface quickly in unexpected places. The whales come to Glacier Bay in Southeast Alaska in the summer to feed on fish. They winter in the Hawaiian Islands.
The park's vessel management program, in place for years, is working well, Payne said. There have been no reports of vessel strikes or near misses so far this summer. There were no fatal strikes last year.
Fatal strikes, however, have occurred inside the park. In 2001, a pregnant whale died of massive head trauma after being hit by a cruise ship. In 2004, a young whale was found beached and dead, also likely the victim of being struck by a boat.
Glacier Bay National Park - which receives hundreds of thousands of visitors each summer, nearly all of them arriving by cruise ship - is requiring vessels to slow down to 13 knots in two areas where many of the whales have been spotted. Vessels traveling in lower Glacier Bay are restricted to 20 knots and must remain a minimum of a mile from shore or mid-channel.
The national park has capped cruise ship visits at 153 this summer. The park also gets tour vessels, private boats and concession vessels, all whose numbers are limited on a daily basis.
The park is expecting about 400,000 visitors this summer. The park is reachable only by plane or boat.
"The plan seems to be working really well," Payne said Thursday.
Under the program, vessel operators are required to attend a 20-minute orientation session before being allowed to cruise park waters. The requirement does not apply to cruise ships.
In addition to the speed restrictions, operators also must remain at least a quarter-mile from the whales. Those within one-half mile of the whales can't change course or speed to get a closer look.
After being hunted nearly to extinction, there are an estimated 30,000 humpback whales worldwide, with between 6,000 and 8,000 in the North Pacific, according to the National Marine Fisheries Service.