Whale entanglement
On May 10, 2008, a sub-adult humpback whale (Megaptera novaeangliae) was found entangled in what was believed to be local crab fishing gear line in northern Monterey Bay. Members from the local disentanglement network, authorized by the National Marine Fisheries Service, responded. However, after assessing the animal it was determined that the entanglement was not presently life threatening and not likely to become so in the future. It appeared that the entanglement was once more involved and over time the whale had thrown most of the entanglement and was very likely to throw the last remnants in short order. Since any disentanglement effort can be dangerous for the whale as well as any would be rescuers, it was determined that the animal was not a candidate for a disentanglement effort. As much as possible, progress of this animal will be monitored and the action plan revaluated if necessary.

California national marine sanctuaries play host to several thousands of endangered whales including Humpbacks and Blue whales (Balaenoptera musculus) during the summer and fall months, and Gray whales (Eschrichtius robustus) from winter to spring. These animals migrate or swim close to shore directly in heavily fished waters, increasing their chances of getting entangled in fishing gear such as crab / lobster pot lines, drifting nets or other such obstacles.

Entanglement, while most publicized in whales, affects all cetaceans (whales, dolphins and porpoises) by reducing their ability to feed and deteriorating their health in general. Entanglement hinders swimming ability, resulting in drowning or vulnerability to boat strike and the physical trauma from the injuries can lead to infection and subsequent death of the animal. Whale entanglement is one of the most serious threats facing whales and cetaceans. An estimated 300,000 cetaceans die each year from entanglement in fishing gear, indicating that fisheries by-catch is the single greatest human-related cause of cetacean mortality.

  • Within the Monterey Bay National Marine Sanctuary, to report an entanglement for any marine mammal or sea turtle, call the Coast Guard on VHF Channel 16 or the California Entanglement Hot Line: 1 800 853-1964 (For marine mammals and sea turtles).
  • If the initial information you provide suggests a response should be mounted and conditions (weather, sea state, time of day) allow for such a response, please remain with the animal. A large whale is essentially a large needle in a very big haystack. Once lost, they are rarely re-located.
Whale rescue
Fig 1. Humpback entangled in marine debris. Animal disentangled by an experienced team from the Hawaiian Islands Humpback Whale National Marine Sanctuary (HIHWNMS). The gear removed from the animal contained over 22 different types of line and netting. Photo: HIHWNMS, NOAA Fisheries' Marine Mammal Health and Stranding Response Program (permit # 932-1489) (HIHWNMS/ MMHSRP #932-1489)
Assessing whale entanglement
Fig 2. HIHWNMS disentanglement staff pulls themselves up to an entangled whale to assess the entanglement in order to determine how best to safely free it. Photo: HIHWNMS/ MMHSRP #932-1489

Assessing whale entanglement
Fig 3. HIHWNMS disentanglement staff deploys a hooked knife from the end of a pole, while holding position behind the entangled humpback. Photo: HIHWNMS/ MMHSRP #932-1489

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