|
| |
Tangled Up In Blue: Whale Rescues
From: Woods Hole Oceanographic Institution
| By:
Stephanie Murphy |
EDITOR'S INTRODUCTION |
When one of only 300 northern right whales in existence was found ensnared in fishing lines in the summer of 2001, scientists quickly sprang into action. Despite their efforts however, teams of disentanglement experts were unable to free the 50-ton whale. Now, scientists, artists and even robots have teamed up to develop new techniques for freeing trapped animals. In this feature, WHOI's Stephanie Murphy discusses the latest advances in efforts to save whales from life-threatening entanglements. |
 | |
| A model right whale tail, purchased by WHOI scientist Michael Moore, is being used to test new fluke harnessing techniques. During disentanglement efforts, rescuers want to both restrain the fluke to slow the animal and avoid being injured by it. | |
 or 100 days during the summer of 2001, rescue workers using a satellite tagging device anxiously followed an ailing 50-ton right whale, nicknamed Churchill, who had fishing line entangled around his mouth. After five failed attempts to remove the gear, the rescue team--a consortium of disentanglement experts from the Provincetown, Massachusetts based Center for Coastal Studies (CCS)--stopped receiving satellite signals and Churchill was declared dead. Churchill was one of approximately 300 northern right whales in existence, and scientists worry the population might be beyond recovery. |
After the frustrating failed rescue attempts, which included administering sedative to slow him down and to reduce the risk of injury to the team from his fluke, a unique collaborative of scientists, engineers and researchers from marine research institutions around New England convened at WHOI to brainstorm new approaches to improve the success rate of whale disentanglement efforts. |
The disentanglement workshop, which met in December 2001, was funded by the WHOI Green Technology Fund and the Northeast Consortium and sponsored by WHOI, CCS and the New England Aquarium. In their meeting, the group identified key areas of work and conceived of innovative new devices to help their efforts in each area. The focus areas included: entanglement assessment capability; physical restraint, especially the fluke; and chemical restraint (or sedative administration). |
With any whale entanglement, assessment is the first job of the rescue team. When a whale is ensnared in fishing gear, the team must determine where the lines are impinging on the animal and whether it will be able to work itself free of the entanglement. Part of what makes this assessment challenging is determining exactly where the fishing lines are. The lines are difficult to see when tightly wrapped around the flippers, for example, or through the mouth, or otherwise out of sight lines. During the workshop, a subset of researchers and engineers specializing in imaging work developed plans for a towed camera system, which could provide real-time pictures of entanglement lines below the surface of the water, and for mounting cameras in survey planes. |
A second major issue in a disentanglement effort is ensuring the safety of the rescue team, which often requires the physical restraint of the animal. In attempts to free the line from the animal, the team, usually in an inflatable boat, must approach the 50-ton animal, always being aware of its very powerful fluke. If possible, the team tries to restrain the fluke, both to slow the animal and to decrease the chance of being struck by it. To address this issue, the working group decided to try new systems for harnessing the beleaguered whale's fluke. Michael Moore, from WHOI's biology department, and others have been testing four newly designed harnesses on a life-size model of a right whale tail. Michael bought the whale tail model from an artist in Canada, who worked from a cast of a whale named Delilah that died in 1992. Michael towed the tail from a small boat in Provincetown Harbor to test the new harnesses. While the four harnesses were each very different, the tail behaved very well, submerging and surfacing on command. |
 | |
| WHOI scientist Michael Moore and others have been testing four newly designed harnesses on a life-size model of a right whale tail. | |
Finally, to address rescue teams' difficulty with administering sedative, the workshop participants brainstormed new devices. The concept they came up with is called "Robocyamid" named after the cyamid lice that live on the right whale's callosities. The device would be a remote-controlled disentangler, which could deliver a sedative to the distressed animal and then sever the entangled lines. This effort is being undertaken by Terry Hammar, a research associate with WHOI's Applied Ocean Physics and Engineering Department, Michael Moore at WHOI collaborating with David Brunson, a veterinary anesthesiologist from the University of Wisconsin Veterinary School, and Teri Rowles, from NOAA Fisheries. |
The device is being developed by WHOI engineer Mark Johnson and local engineer Richard Arthur, and is an outgrowth of the cantilevered pole techniques Michael Moore and others use in their cetacean research. Using a pole, rescue teams would deploy a device made up of four suction cups to create a stable platform. Moving between the cups could be a stage with a cutting tool and an auto-injecting syringe attached. |
|
| |
