Studying the travels of marine mammals may influence the construction of offshore wind power

Researchers are using sound to track the highly endangered North Atlantic right whale, Eubalaena glacialis, shown here with a calf (top), in Maryland's proposed wind-power lease zone (bottom). Helen Bailey, a scientist at the University of Maryland Center for Environmental Science, prepares a C-POD device that will be left on the ocean bottom for three months to record data about clicks from dolphins and porpoises. Credits: photographs, NOAA/NMFS (top), Sarah Brzezinski (middle); map, Bureau of Ocean Energy Management

EVERY THREE MONTHS, a crew of scientists and assistants rides a boat out into the Atlantic Ocean off Ocean City to do a kind of submarine surveillance — but not the Defense Department kind.

The scientists retrieve a set of hardy, underwater microphones and data recorders from the ocean bottom and replace them with similar units. Then the researchers return to their labs at the University of Maryland Center for Environmental Science (UMCES) and Cornell University carrying reams of data about the signature sounds made in these waters by dolphins, porpoises, and the critically endangered North Atlantic right whale. By analyzing data about the animals' clicks and calls, the researchers hope to learn more about where these animals live and when they travel through these offshore waters.

This research and related new findings are expected to help answer practical and timely questions about this coastal ocean zone. Will these creatures be jeopardized by the construction of offshore wind turbines? Can steps be taken to reduce the risks?

"'Where in the ocean are whales?' is a fairly basic question to ask," says Aaron Rice of Cornell University, one of the project scientists, "and it's kind of astonishing that in this day and age, despite the amount of attention paid to the pressures facing whales, it's still a mystery. This will be the first time in Maryland waters that we'll be able to get a complete, year-round picture."

Where the whales are and how they will be affected by wind turbine towers have become salient questions because of hopes that Maryland could become a leader in developing this renewable energy source. The federal Bureau of Ocean Energy Management (BOEM) issued leases in 2014 allowing U.S. Wind Inc. to explore building a wind farm off Maryland's coastline. The corporation plans to build up to 100 wind-turbine towers generating a total of 500 megawatts.

This year U.S. Wind began exploring its 124-square-mile lease zone, located from 10 to 27 miles offshore, to identify locations for the turbines. If the project obtains financing and moves forward, it could be one of the first offshore wind farms in the United States.

The research by UMCES and Cornell is part of a set of studies in recent years that have counted a variety of animals in the coastal ocean, including birds and sea turtles, that might be affected by offshore energy projects. Research has been organized and funded by the Maryland Department of Natural Resources (DNR) and the Maryland Energy Administration (MEA) with additional funding from the U.S. Department of Energy and BOEM.

The development of offshore wind energy raises concerns because crews drive piles into the ocean bottom to install the turbine pylons. This work creates loud underwater noises that pose risks to the survival of marine mammals. The sound waves can permanently damage the hearing of whales and dolphins nearby, and farther away, they can interfere with communication among members of the same species. The noise can cause animals to move to avoid it. If whales take a detour from their preferred migration route, it could lengthen their journey or increase the frequency of collisions with cargo ships, says Helen Bailey of the UMCES Chesapeake Biological Laboratory, leader of the marine mammal research project.

Under the Marine Mammal ProtectionAct, federal agencies are required to manage these animals to maintain sustainable populations. The federal Endangered Species Act also protects the right whale and other species of baleen whales in the Northern Atlantic.

The scientists who are tracking whales and dolphins in the coastal ocean are using different but complementary scientific methods. One approach is to count individual animals through visual observations. The Virginia Aquarium, for example, has counted whales during a series of airplane flights over the wind-power lease zone, and the Biodiversity Research Institute has sent out observers on boats and planes. Using those counts, researchers can extrapolate to arrive at population estimates covering a wide area. But the counts can be made only during daylight hours and good weather.

The UMCES and Cornell groups, on the other hand, are gathering data around the clock by using the underwater microphones to pick up whale calls and dolphin clicks — telltale clues that the animals are nearby. "It's a really great technique for looking at distributions of animals over long time periods," Bailey says. In all, the data collection is planned to run for two years, through 2016. Maryland's Department of Natural Resources obtained funding for this research from BOEM, which licenses offshore wind energy projects, and the Maryland Energy Administration.

The Cornell group is using the whale calls to identify their locations and potentially track the direction these animals take as they move through the wind-power lease zone. Tracking the right whales is a priority because only about 450 are left. The UMCES researchers are recording data only about the presence or absence over time of common dolphins, bottlenose dolphins, and harbor porpoises.

Determining where dolphins and whales are located in Maryland's coastal waters is a necessary step to help reduce risks posed to these animals by the construction of offshore wind projects, Bailey says. For example, if dolphins and whales are absent from the construction zone at predictable times of the year, pile-driving might be scheduled for those times. If Maryland becomes a pioneer in developing these projects, it could show other states a way to build them without endangering the animals that live in their waters.