Humpback whale disentangled in Massachusetts Bay - 8/3/2006

Update, 8/3/2006: The PCCS humpback whale research program has identified this whale as the 2005 calf of Sickle.

The PCCS disentanglement team responded to a report from sport fishermen of an entangled whale yesterday morning (8/2/06), a few miles east of Plymouth. After a rather complicated disentanglement operation, the humpback whale was free of its entanglement by early afternoon. The successful disentanglement of this whale would not have been possible without the dedication of Donald Clancy, aboard St. Andrew, for standing by this animal.

The whale had a set of lobster gear (rope, buoys and a lobster trap) anchored within its mouth, making normal behavior difficult. Throughout the entanglement operation, the whale extended both flippers (humpbacks in the North Atlantic have very long, white flippers that often show green in plankton-rich water), and never dove very far below the surface. The animal was also very sensitive to vessel approaches and spent much of the time smashing its flukes at the surface.
 

Diagram of the entanglement. Note line with trap exiting the left side of the mouth and longer line exiting right side of the mouth.

Rope extended from either side of the whales mouth: on the left side the rope ran to a series of marker buoys trailing approximately 80-feet behind the flukes; on the right side the rope ran to a lobster trap just behind the right flipper, and very close to the flank. Inside the mouth, the rope was woven between plates of baleen (humpbacks have baleen, not teeth, hanging from either side of the upper jaw to filter food from seawater).

After assessing the entanglement, the team decided to attempt disentanglement, especially considering the amount of gear on the whale and the potential for future complications (rope wrapping other body parts or snagging more gear).
 

The sports fishing vessel, St. Andrew, stands by during the disentanglement. PCCS image taken under NOAA-Fisheries permit 932-1489, under the authority of the U.S. Endangered Species and Marine Mammal Protection Acts - please request PCCS permission for use.

Using a small inflatable boat deployed from the R/V Ibis, the team approached the whale and replaced the marker buoys with larger buoys for extra flotation in an effort to slow the whale. While the whale did slow a bit, it began pumping its flukes at the surface, making close approaches too difficult. After re-assessing the entanglement the team decided to remove the lobster trap first and attempt to pull the remaining rope from the mouth. Using a grappling hook attached to a long length of line, the team added large buoys and a sea anchor to the rope attached to the trap. With this heavy drag and the surge of the whale, this line parted, removing the trap. The team then added the flotation and drag to the remaining line exiting the left side of the mouth. The whale reacted actively to this flotation and used the extra drag to its advantage. Opening and closing its mouth, and thrashing at the surface, all of the remaining entangling rope came free of the whale. Once free, the whale swam off quickly.

Left side of whales head as it uses the drag of the buoys to dislodge the remaining rope. PCCS image taken under NOAA-Fisheries permit 932-1489, under the authority of the U.S. Endangered Species and Marine Mammal Protection Acts - please request PCCS permission for use.

The gear recovered from this whale will be used in ongoing studies aimed at modifying fishing gear to prevent entanglements. The whale has not yet been identified by the PCCS humpback whale research team and any updates about this whale will be posted here. Footage gathered by news organizations of this event can be found here: http://cbs4boston.com/video/?id=22839@wbz.dayport.com.

click here for a list of previous entanglements