Cargo and cetaceans

Researchers already have a pretty good idea about where to find Hawaii’s two most famous cetacean species.

Humpback whales and spinner dolphins are found — and easily studied — in the islands’ near shore waters, University of Hawaii graduate student Alexis Rudd said. Much less is known about the other 23 species that live around the state.

Part of the problem, she said, is those animals don’t move in close to shore and, with Hawaii’s rough waters, can be hard to find. Armed with funding, and a generous offer from interisland shipping company Young Brothers that allows her to hitch a ride and drag her sound recording equipment from the back of a barge, Rudd is helping to locate those lesser known species.

“You can’t manage an animal and protect it if you don’t know where it is,” she said.

She took her first trip in July 2010 and, since January 2011, has been on one of the company’s tugs, with her equipment on the barge behind it, twice a month ever since. Once a month she travels from Honolulu Harbor to Kauai’s Nawiliwili Harbor. The other trip takes her to Kawaihae Harbor, across the notoriously rough Alenuihaha Channel. So far, she’s spent about 90 days on board.

Her adviser asked a Young Brothers executive about the possibility of Rudd riding along with the boat. Young Brothers said yes, and she started her research. Doing so saves her thousands of dollars. A research vessel based on Oahu costs about $10,000 a day to rent. A fishing boat, which wouldn’t be big enough to travel through some of the rougher waters, costs about $1,000 a day to charter.

Young Brothers lets her do it for free.

“It’s not a lot for them to have me sit on the boat,” she added.

Rudd doesn’t just drop her equipment behind the barge and settle down for the several days of travel each journey requires. She watches, from just outside of the bridge, for whales and dolphins, noting each sighting and recording the species. A computer program can analyze each sound and tell her the animal likeliest to make it. Her visual confirmation of the animals backs up that analysis.

Sometimes, like the trip she made to Kawaihae Monday and Tuesday, the weather is nearly perfect, with flat water. That’s good for her — she said she never got seasick until she started riding on the tugs — but even better for whale and dolphin spotting.

The weather isn’t always so great.

“If I’m standing up there, the waves will come over and soak me,” she said.

At that point, she often heads inside to continue her observations from behind the bridge’s glass windows.

The work has given Rudd new insights into the balance between commerce and conservation. On a research excursion off the Maui coast, Rudd and other scientists saw a Young Brothers tug pulling a barge. The other scientists were horrified, worried the boats would strike and kill a whale. Rudd said she waved at the boat, recognizing the crew. And, she said, she knows the boats weren’t moving faster than 10 miles per hour, a speed at which very few whale strikes occur. Her GPS data backs up company comments about the speed at which the barges travel.

Rudd, who is originally from California, completed her undergraduate work at the University of Puget Sound in Tacoma, Wash. She began her graduate studies at UH in 2007, where she is working on her doctorate in zoology. Funding permitting, her study of whale and dolphin sounds won’t wrap up for several more years.

“For a long-term study, where you want to find seasonality patterns, ideally you want at least five years,” she said.

She isn’t just looking to find out where the animals are located.

“If I have time, I’d like to look at whether there’s a dialect difference between the locations,” she said. “I’d like to see if they have different accents.”

Rudd blogs about her research at bioacoustics.blogspot.com.