Monday, August 08, 2011

{Press} A whale of a task: Restoring the right whale population

Bangor Daily News | August 8, 2011

"Though it has been called “the urban whale,” little about the pace of modern life seems to apply to the North Atlantic right whale.

The species, one of the rarest and most endangered of all marine mammals, is often found in coastal shipping lanes and commercial fishing areas, which is how it got its relatively “urban” reputation. In the Gulf of Maine, researchers have found congregations of right whales in Jordan Basin and at Cashes Ledge.

Despite its proximity to the hustle and bustle of human marine activity, the whale is known for swimming at an estimated top speed of less than 6 mph and, in terms of the overall population, growing at an even more glacial rate of only 1 or 2 percent a year.

What it is most known for, however, is its critically low population estimates. It is so small — the latest estimate suggests there are between 450 and 470 — that scientists are concerned that the North Atlantic right whale could go extinct. The whales’ low population growth rate makes their situation especially dire, scientists have said.

The species is legally protected under the federal Endangered Species Act and Marine Mammal Protection Act, and because of those laws fishermen in Maine and elsewhere are facing restrictions on the gear they use to fish. Entanglements in such gear continues to cause the deaths of right whales, whale advocates say, and is believed to have caused scars on possibly more than three-quarters of all North Atlantic right whales.

In 2009, the federal National Marine Fisheries Service ordered lobster fishermen who set traps outside a distance roughly three miles from shore, including in the Gulf of Maine, to use expensive sinking ground lines between traps instead of vertically arcing loops of floating rope. The floating rope was cheaper and less likely to get caught on the rocky ocean bottom, but whale biologists said it posed more of an entanglement hazard for whales.

Ropes that connected traps to surface buoys were exempt from the 2009 law, but the National Marine Fisheries Service is in the midst of holding a series of public meetings along the East Coast to gather input about how to reduce the threat of entanglement in these ropes, also known as vertical lines.
Fishermen concerns

Lobstermen in Maine, who brought ashore a total of $313 million worth of lobster in 2010, have expressed frustration with the restrictions. The prices fishermen are getting for their lobster remain relatively low, many have said, while their expenses for fuel, bait and gear remain consistently high.

According to Maine Department of Marine Resources statistics, there are about 6,000 licensed commercial lobstermen in Maine.

“In the economic times we’re in now, jobs are at a premium and you’re asking us to make an extreme sacrifice,” Deer Isle fisherman Leroy Bridges told federal regulators at a July 12 meeting in Ellsworth about whale-safe gear restrictions. “We fished the way we fished because there was a need.”

One aspect about the prospects of additional restrictions that fishermen find confounding is that new mandates are being considered at the same time that the North Atlantic right whale population is increasing. According to official estimates, the number of right whales in the North Atlantic has increased from fewer than 300 two decades ago to around 450 now.

Why, some fishermen have asked, do they have to face more restrictions if the whale population is going up? Why is the chance of even one whale coming into contact with one of potentially several million traps in the water considered too high a statistical risk? How much longer will they have to abide by rules aimed at protecting a whale that many fishermen claim they have never seen?

“We’re still having [restrictions] thrown at us,” Bar Harbor lobsterman Jon Carter said at the same July 12 meeting. “[Our industry] is being driven by things that don’t care that we’re here.”
Population growth

According to a November 2010 National Marine Fisheries Service stock assessment of the North Atlantic right whale, the population is believed to have increased by more than 50 percent in the past 20 years. Fewer than 300 animals were estimated to exist in the 1990s, while the latest estimate is approximately 450.

The 1990s were a bad decade for right whale calf births. Twenty-two were born in 1996 and 20 more in 1997, but for each of the three years before 1996 and after 1997, fewer than 10 calves were born. In 2000, only one calf was born among the entire population.

Since 2001, however, the lowest number of calves born in any year was 17 in 2004. In 2009, 39 calves were born — the most in recent memory — while 19 were born in 2010 and 22 this year.”

According to the assessment, 297 calves were born from 1993 to 2009, more than twice as many that were born during the preceding 12 years. But 21 calves that were born from 1993 to 2009 are believed to have died later in their birth years, with a few more first-year deaths suspected for calves born in 2010 and 2011.

Scientists and others have expressed mild optimism that the population seems to be increasing. Still, because the species’ population remains so small, and because several whales are believed to die each year from fishing gear entanglements, ship strikes and natural causes, scientists believe the whales are not reproducing quickly enough to have long-term viability as a species. Even the premature death of one whale, especially a reproductive female, represents a significant setback to the right whales’ genetic diversity and future, according to advocates.

“That’s not a good rate of growth to recover a population,” Dr. Amy Knowlton, a researcher with New England Aquarium in Boston, said last week about the whales’ estimated 1 to 2 percent growth rate. “We’re only inching toward 500.”

Knowlton said two right whales died off the southeastern U.S. this past winter because of entanglements, and that as much as 82 percent of the North Atlantic whale population has been estimated to have scars from entanglements.

“It happens frequently,” she said. “It is not an insignificant problem.”
Other right whale populations

Knowlton compared the North Atlantic right whale population to the more numerous right whales in the southern hemisphere, which the London-based International Whaling Commission estimates to have a population of around 7,500. Despite their higher numbers, the commission has banned commercial hunting for southern right whales, as it has for all whale species.

Knowlton said it is not unusual for southern right whales to have 300 calves in any given year. She said the relative lack of human activity in areas of southern right whale habitat is thought to be a main reason why the number of southern hemisphere whales has increased more dramatically than that of their northern cousins.

“They don’t have the same density of fishing gear and they don’t have as intense shipping,” Knowlton said. “They don’t have as urban an ocean as we do up here.”

Southern right whales are considered a separate species from right whales in the North Atlantic or North Pacific, which likewise are considered separate species. The population of North Pacific right whales is thought to be similar to that of the North Atlantic species — measured in the hundreds rather than the thousands.

Because of the availability of food and their physiology, right whales do not swim past the equator in either direction, but southern right whales have the ability to swim among the southern Atlantic, Indian and Pacific oceans. Those in the north Atlantic and north Pacific oceans cannot swim north into other oceans because of the arctic polar ice cap.
Reproduction and mortality

According to David Laist, policy and program analyst for the federal Marine Mammal Commission, scientists aren’t sure why North Atlantic right whales started producing more calves in the 2000s. It could be related to climate change and may have been helped by regulations implemented in the mid-2000s that required large ships to reduce their speeds in known right whale habitat areas off Florida, Georgia and Massachusetts, he said.

Laist said there is no effective way to boost the whales numbers by other means, such as through artificial insemination or by breeding them in captivity.

“We don’t know exactly what it was,” Laist said recently about the increase in calves. “The only thing you can do for the right whales is reduce the known human-caused mortalities.

The reason this is difficult is because there are so few options.”

Though the increase is “encouraging,” Laist said, there is no guarantee that the low reproduction rate of the 1990s will not return.

Laist said he believes right whales have natural lifespans of 100 years or more but that deaths caused by ship strikes and entanglements are hampering the species’ reproductive success.

No one really knows how many whales die each year because those that do, especially as a result of entanglements, usually just “disappear” instead of being found by humans, he said.

Calves especially are vulnerable to dying in their first year, but experienced whale mothers are more successful than their younger counterparts at raising young, he added. If the whales generally live shorter lives, it likely impedes the number of chances cows have to successfully produce offspring.

“There’s no question the number of [premature] deaths is affecting population,” Laist said.

“The population is still very vulnerable.”

As for the ideal population size for the North Atlantic right whale, Laist said no one knows.

The question is academic because there is no scientific data about how many right whales there used to be before commercial whaling rendered them nearly extinct 100 years ago.
Endangered species listing

If the species can increase to “several thousand” animals, scientists and regulators likely would agree that its official status could be changed from “endangered” to “threatened,” a designation that means their situation is less dire. Barring any setbacks in the calving rate of the past decade, Laist said such downlisting likely would take “several decades” to accomplish. More specifically, he said he could see that happening in less than 100 years from now, but probably not less than 50.

“Everything about right whales is slow,” Laist said.

According to David Gouveia, marine mammal coordinator for the National Marine Fisheries Service, the agency’s revised recovery plan, which was drafted in the early 2000s, calls for the whales’ population to increase at a minimum rate of 2 percent a year over 35 years, which should result in the population doubling over that time. Only “about 300 individuals” were thought to exist at the time the plan was revised, the document indicates, which suggests that officials would like to see around 600 animals before 2040.

Gouveia indicated last week in an email that such a recovery could result in the whales’ status being changed to “threatened.” The plan does not set any benchmarks for removing right whales from the list altogether, he said. There are several variables that figure into right whale population projection models, he said, but the general sense among regulators and scientists is that it could take between 50 and 100 years to have a population of 1,000 whales or more.

“Decades of population growth likely would be required,” before the National Marine Fisheries Service would consider delisting right whales as either endangered or threatened, he said.
Lobstermen’s group: more research needed

Lobstermen, however, don’t want to wait that long to determine what kind of future their industry might have.

Patrice McCarron, executive director of Maine Lobstermen’s Association, said last week that lobstermen cannot stumble along indefinitely absorbing new restrictions based on theories. There needs to be scientific proof, not just anecdotal evidence, she said, that mandated lobster gear restrictions actually are making conditions safer for whales.

“I don’t think we should have to do something forever if we don’t know whether it’s working,” McCarron said.

Beyond doing research to examine the effectiveness of required gear changes, there should be more proactive research on whale behavior and other possible gear modifications, according to McCarron.

She has said co-occurrence models recently developed by the National Marine Fisheries Service, which show where whales and lobster fishing gear are most likely to come into contact with each other, represent an improvement in scientific data. A few years ago, during deliberations about the sinking ground line mandates, there were no probability models being used or considered by regulators, she said.

The models show that the areas in Maine where whales and lobster gear are most likely to overlap are off eastern Washington County and York County, though lobster buoys and whales can be found along the entire coast.

More specific research about interactions between whales and fishing gear would help determine how and where whales are getting entangled, McCarron said.

“The industry really needs to push for better information,” McCarron said. “If you don’t understand what’s happening, you’re in a position of not knowing what you’re trying to solve.”

Even though scientists have raised concerns about the high percentage of right whales that have apparent entanglement scars, McCarron said the marks suggest that whales can come into contact with fishing gear but then escape and remain healthy. If there is something that is helping whales swim away relatively uninjured from traps without ropes dangling off their bodies, it would help both fishermen and whales to find out what it is, she said.

“I think the fact that they’re swimming away happy — that’s huge,” she said.

If lobstermen can find a way to earn a living by catching lobsters without posing any threat to whales, she said, the industry will have a secure future.

“Even if the whales are still endangered, it doesn’t mean we would continue to be regulated,” McCarron said.

But for Knowlton, who comes to Lubec every summer with other New England Aquarium researchers to study right whales in the Bay of Fundy, how whales are affected by fishing gear should go beyond simple numbers.

Knowlton agreed that it could take 100 years or more for the right whale population to increase to a biologically viable level. In addition to boosting the species’ likelihood of survival, she said, humane treatment of the charismatic marine mammal should be considered a significant motivating factor for protections that are put in place.

The ideal approach is not just to make sure there are enough whales so that the species can survive entanglements and ship strikes, according to the scientist. The whales should be treated with empathy, she said, so that none has to suffer the agony of getting entangled and then suffering a slow, painful death that often involves starvation or drowning.

“They suffer a terrible ending to their lives,” Knowlton said."

Thursday, August 04, 2011

{Press} Hidden Risks For North Atlantic Right Whales In Cape Cod Bay

Red Orbit | August 4, 2011

"Tracking their dinner may be the best way to help North Atlantic right whales in Cape Cod Bay avoid being hit by recreational and commercial boats, according to a team of researchers who studied the whales for two years.

"Auto-detection buoys are making a remarkable attempt at recording the whale sounds to show when whales are in the area," said Susan Parks, assistant professor of acoustics and ecology and senior research associate, Penn State Applied Research Laboratory. "But North Atlantic right whales don’t make call sounds when they are eating, so they don’t show the whales when they are feeding."

North Atlantic right whales, like Southern and North Pacific right whales, are an endangered species. The researchers report in the Aug 3 issue of Biology Letters that "North Atlantic right whales have the largest per capita record of vessel strikes of any large whale population in the world."

These whales are susceptible to being struck by boat propellers when they are in Cape Cod Bay because the whales feast on copepods — tiny crustaceans the size of sesame seeds — that school in very large masses just below the water’s surface. The whales eat for about 18 hours. consuming between 125 to 400 pounds of copepods an hour with their mouths open like large scoops.

After two years of study, the research team determined that during the day when they feed, the North Atlantic right whales spend most of their time between the surface and 13 feet below. When the whales are below the surface, but still in the reach of boat propellers, they are invisible to people on the boats and consequently may be hit unintentionally.

"We found that every whale spent a lot of time just below the surface, where they can’t be seen while feeding," said Parks. "It is a good thing that the whales are in Cape Cod Bay in April when it is pretty cold and not a lot of recreational boating is going on, because any boat, even small recreational boats, could bump into them."

The researchers have been studying the whales in Cape Cod Bay by placing suction cup tags — digital acoustic recording tags developed by the Woods Hole Oceanographic Institution — on the whales and recording their depth through the day.

The researchers also investigated the whale’s preferred prey, the copepods, using acoustics and physical sampling methods. Using an echosounder — a device like a depth sounder — that could produce multiple sound frequencies, the researchers tested a variety of depths from about 1.5 to 90 feet below the surface looking for the copepods. Because sound waves bounce off objects, the scientists were able to locate tiny objects that could be copepods and eliminate large fish and crustaceans because of their large size. However, sound waves can locate objects of the proper size to be copepods, but cannot not detect whether these objects are copepods or inanimate debris of the same size.

To ensure that what the ecosounder recorded was actual prey, the researchers also looked at netted and pumped samples. Using very fine mesh nets less than 1640 feet from a tagged whale, they retrieved samples of the water and preserved any wildlife in formalin for identification. They also pumped samples from the water and preserved the samples in the same way.

The physical samples matched the acoustic data and showed that "there was a strong relationship between the depth of the center of a feeding whale’s mouth and the mean depth of the top 5 percent concentration of their prey in the water column," the researchers reported.

The researchers suggest that the development of moored devices that can remotely detect the copepods may provide a way to remotely monitor where unseen and unheard right whales may be and provide a warning to avert ship collisions.

"The daytime and nighttime behavior may be different, but we don’t know the nighttime behavior because every whale we tagged with a suction cup recorder slipped out of it before evening," said Parks.

Other researchers on this project were Joseph Warren, assistant professor, School of Marine and Atmospheric Sciences, Stony Brook University; Karen Stamieszkin, associate scientist, and Charles "Stormy" Mayo, senior scientist, Provincetown Center for Coastal Studies; and David Wiley, research coordinator, National Oceanic and Atmospheric Administration Stellwagen Bank National Marine Sanctuary

The Office of Naval Research, NOAA and the Massachusetts Division of Marine Fisheries supported this work."

Wednesday, August 03, 2011

{Press} Endangered Whales Dine at Dangerous Depths

Discovery News | Jessica Marshall | August 3, 2011

THE GIST

- Endangered right whales feed at depths just below the surface where they're vulnerable to collisions with ships.
- This depth corresponds to high concentrations of their copepod prey.
- Ship collisions are a leading threat to this species, which numbers only between 300-400 individuals.

Critically endangered North Atlantic right whales foraging in Cape Cod Bay in the spring spend most of their time just below the surface where they can't be seen but remain vulnerable to collisions with ships, according to a new study.

The whales appear to be following their food, because the researchers also found high levels of copepods, tiny crustaceans the size of a grain of rice, at the same depths.

"It makes sense that whales are spending time where their food is," said Susan Parks of Pennsylvania State University, lead author of the study published today in Biology Letters.

Still, the fact that the whales spent nearly all of their time just below the surface came as a surprise to the team.

"In the past I had known that right whales feed at the surface in Cape Cod Bay; you can see them swimming through the water with their head above the water and their mouth open," Parks said. "What was really surprising to me in this study was how much time the whales were spending just out of sight but at a really dangerous depth for a boat to run into them."

In fact, with the aid of trackers attached to the whales using suction cups, researchers knew that at times as many as 10 whales were within their visual range, yet they could see almost nothing at the surface. "We would know that they were right in front of us," Parks said.
athletes

While one part of the team tracked the whales' locations and sounds, another part of the team monitored the concentrations of copepods in the water column, collecting samples and using sonar techniques to determine copepod numbers at various depths.

Consistent with other studies of North Atlantic right whales, the results showed tight agreement between the depths of the whales and their prey, but the whales' early spring passage through Cape Cod Bay is special because the prey aggregate so near the surface.

In other locations the prey are found deeper in the water, drawing the whales on deeper dives to feed. "This habitat at this time of year makes them particularly vulnerable," Parks said.

A large proportion of the population faces this vulnerability: around 45 percent of the North Atlantic right whale population gathered in the area in early spring 2010.

The findings could aid efforts to conserve the species. Approximately one-third of all right whale deaths result from ship strikes or entanglement in fixed fishing gear according to the National Oceanic and Atmospheric Association. NOAA also reports that one to two deaths per year of reproducing females by human activities could lead to the species' extinction.

A number of conservation measures are already in place including aerial and ship surveys to spot whales, mandatory speed reductions for large ships in key locations at certain times of year, and underwater detectors to listen for the whales.

"This is a suggestion that another way we could improve our protection for the whales is being able to monitor where in the water column the food is," Parks said.

Meanwhile, the findings could also be helpful in ensuring that regulations enforcing slower ship speeds continue, said Doug Nowacek of Duke University in Durham, NC. The current speed restrictions mandated by NOAA are set to expire in December 2013.

"We need to get those regulations to be maintained in perpetuity, and not sunsetted," Nowacek said. "Ship strikes and entanglements in fishing gear are the two most significant conservation concerns for this species."

Tuesday, August 02, 2011

{Press} Right Whale Roadkill

Science NOW | Helen Fields | August 2, 2011

"Right whales are said to have been the "right whale" for whalers to hunt because they're slow movers and they're close to the coast. Unfortunately, they've turned out to be right for something else too: getting hit by ships. A new study finds that in Cape Cod Bay, right whales hang out just below the water's surface—invisible to any watchers on ships—in patches of food. The new information could help scientists and managers figure out better ways of keeping whales from getting run over.

The waters around Boston are thick with whales—and ships. Endangered North Atlantic right whales visit Cape Cod Bay, the body of water encircled by Cape Cod's curled arm, every spring. The whales are there to suck down copepods, crustaceans about the size of a sesame seed. In the past 30 years, five right whales are known to have been killed by ships in and around Cape Cod Bay. Five deaths in 3 decades may not sound so bad, says Susan Parks, a biologist at Pennsylvania State University, University Park, "but if you have three or 400 individuals and a relatively low population growth, ... people have done studies that have shown the loss of a single reproductive female could tip the scales for this population."

To find out just what whales were doing that made them so vulnerable to ships, Parks and her colleagues tagged whales in Cape Cod Bay in April of 2009 and 2010. They stalked their targets in a small boat, with Parks balancing a nearly 17-meter-long carbon-fiber pole with an electronic tag on the end. "You just wait behind them until they come up to breathe," she says. When the whale's broad back appeared, she smacked down the suction-cupped tag.

The idea was for the tag to stay on for a day and a night, but the whales didn't cooperate. They jackknife while feeding, which makes some of the suction cups pop off. "And then right whales are really social, so every afternoon pretty much every tagged whale we thought was going to get a tag into the night would join other right whales and they'd roll around and touch each other and the tag would pop off," Parks says. "It was really frustrating."

But she did get data from 13 tagged whales in the daytime. And while one boat followed the tagged whale, another toured the area, towing an instrument that uses sound waves to measure copepods in the water and occasionally sampling to identify the copepod species and see where they were.

Parks found that the whales spent the majority of their time with their backs between 0.5 and 2.5 meters below the surface. They kept their mouths at the same depth as the thickest patches of copepods. That suggests the whales are very good at finding their food—and at putting themselves in the worst position for ship strikes. A black whale approximately 2 meters below the surface is easy to hit but invisible from the bridge of a large ship. "Just knowing right whales are in the area was one thing," Parks says. "Knowing that they're in the area and you're not going to be able to see them during the day was something we wanted to point out to people."

This kind of basic observation of how whales spend their time underwater has only become possible in the past few years, with the development of new tags, says Ari Friedlaender, a marine ecologist at Duke University in Durham, North Carolina, who studies whales. "This is a really strong piece of work, to show that you can describe what these whales are doing in a very basic way" and then apply it to conservation, he says. "Right whales aren't going to change their foraging behavior. Even if they do, it's not for the right reasons. So we need to be the ones that are responsible for our actions. ... We can do things differently to make sure we don't hurt these animals."

North Atlantic right whales are already getting a lot of help. Since 1999, ships plowing through right whale habitat have had to slow down during the time of year when the whales are around. In the southeastern United States, planes spot the whales and warn ships; near Boston, buoys listen for right whale calls. These measures are helping the whales. "We're gaining ground, which is much better than where we thought were 10, 15 years ago," says Moira Brown, a whale biologist at the New England Aquarium in Boston, who was not involved with the study.

"This kind of paper is suggesting a little bit more fine-tuning, that we can do an even better of job of figuring out where the whales are," Brown says. It might be possible for the buoys that listen to whales to also carry instruments that measure plankton, giving managers a better idea of where the whales are likely to be. "And the whales are doing their part, you know," she adds. "They're having calves."