What is a success? Why do we sometimes leave gear on a whale?
Removing any life-threatenning gear from a whale is the main objective of any disentanglement operation. Add to that full documentation of the entanglement and safety (for people and whales). This does not necessarily mean that every inch of line will be removed from a whale. Research has shown that a large number of whales become entangled every year but many shed the gear on their own (it is impossible to say how many entanglements end in fatality). During some rescue operations, some gear may be left on the whale with the understanding that the whale will likely shed that gear on its own. Line may be left in the mouth with the ends shortenned, likely to be cast off naturally at the next bout of feeding. If line is embedded within the whale, the line may be shortened, allowing the wound to reject the foreign body at its own pace.
