Bad weather hinders census of humpback whales
By Jan TenBruggencate
Advertiser Science Writer
The state's whale experts say they have no evidence that the long-term increase in humpback whale populations around Hawai'i is changing, but have no reliable numbers this year, largely because bad weather has made it difficult to spot the marine mammals.
"We have no sense that they're down," said Lou Herman, director of the University of Hawai'i's Kewalo Basin Marine Mammal Laboratory. "There is no indication that I'm aware of that the population is down, and I wouldn't expect that to be the case."
Lots of rain over the past two months has obscured visibility in the waters around the Hawaiian Islands and has reduced the number of volunteers turning out to count whales.
"A lot of people are saying there weren't as many (whales) this year, but with the weather, we may not be able to see them," said Amy Hellrung, a research associate with the Maui-based Pacific Whale Foundation.
Kevin Merrill, who for 10 years has run the Kona-based Dolphin Discoveries whale-watch firm, said the year seems normal in terms of numbers, but odd in patterns of arrival and departure.
"I have the feeling that it's an average year, but the distribution is different. The season seems to be coming to a conclusion earlier than normal," he said.
Furthermore, he felt that a lot more whales than usual arrived in the early part of the season.
Researchers estimate there are roughly 5,000 humpbacks that come to Hawai'i each winter, and the number is increasing by about 7 percent a year. But even with aerial surveys along carefully established grid lines, population numbers can only be estimates.
Researchers hope to get an accurate census through a three-year research program called SPLASH, for Structure of Populations, Levels of Abundance and Status of Humpbacks. It involves counting, photographing and taking genetic material from humpbacks throughout the North Pacific, using as many as 100 researchers from a range of private, national and international agencies.
Data from a series of volunteer counts are being processed, but population estimates for this season won't be available for several more months.
"We had some really bad weather, and those factors will influence our results," said Naomi McIntosh, manager of the Hawaiian Islands Humpback Whale National Marine Sanctuary, which oversaw a series of statewide volunteer counts.
Dave Matilla, science and rescue coordinator with the sanctuary, was reached via wireless phone on a boat in the channel between Maui and Lana'i, where he was photographing scar patterns on whales. He said there appear to be plenty of whales around this year.
"We're having no trouble seeing them," Matilla said.
Reach Jan TenBruggencate at jant@honoluluadvertiser.com or (808) 245-3074.
