Orca Entanglements

WMMC 2019 logoAt the World Marine Mammal Conference (9-12 December 2019, Barcelona, Spain), Dr Ingrid Visser, together with Dr Krista Hupman presented a poster about orca entanglements.

New Zealand has a high rate of orca entanglements and sadly this often results in their death.  If you find an orca that is entangled, IMMEDIATELY CALL 0800 SEE ORCA (0800 733 6722).  Do not attempt to disentangle the orca – even small bits of rope left embedded in their skin can cause a slow and painful death.  If the orca is struggling to remain afloat, SLOWLY AND CAREFULLY see if you can approach from the side or behind and hook the rope from below the animal.  Secure the rope to your vessel to take the pressure off the orca and allowing it to breath.  Do not attempt to disentangle the orca.  Await instructs over the phone, please as each situation is unique and the proper methods must be used to free the orca and ensure that it is not injured in the process.  Thank you.


The Abstract (summary) for the poster is:

The New Zealand coastal population of orca (killer whales, Orcinus orca) is classified under the
Department of Conservation (DOC) Threat Classification System as ‘Nationally Critical’, the
highest category possible.   This classification is based on, inter alia, their low population number
(fewer than 200 individuals) and the wide range of threats they face including critical habitat
destruction, pollution bioaccumulation, boat strikes, strandings and fisheries interactions which
include shootings as well as entanglements. The latter is of particular significance due to the high
number of events with least 21 orca (of both sexes and all age-classes including adults, juveniles and calves) becoming entangled since 1979. Entanglements have occurred in commercial fisheries gear, including gill and trawl nets, long-lines and cray-pot lines, as well as likely entanglements with private fishing gear from pots, rods and/or handlines. The outcome of these entanglements included seven confirmed deaths, another nine whose fate remains unknown (due to poor documentation) and only five who were actively disentangled and released. The DOC, although legally mandated to protect New Zealand marine mammals, did not participate in any disentanglements and instead the public and volunteer entanglement response networks responded and released them. Only one orca was photo-identified during the disentanglement process and she has been resighted on numerous occasions over the five year period since her release. To minimise entanglements of orca, easily-applied mitigation options are presented and these methods may also help reduce entanglements of other cetaceans around New Zealand. In addition to implementing mitigation options it is vital that the DOC work with the volunteer entanglement response networks to improve disentanglement rates for this Nationally Critical population to ensure its viability.

The poster is available as a pdf: