Published online by Cambridge University Press: 11 January 2023
Japanese whalers use the electric lance as a secondary method of killing minke whales (Balaenoptera acutorostrata). The lances are dropped into the body, and currents varying between 2.2 and 14. OA, with a mean of 6.8A, are applied.
When currents of 5A were applied to the carcasses of dead whales, varying in size from 1.8 to 15.7m in length, no current densities induced in the target organs were sufficient to cause either insensibility (10mA cm−2 in the brain), or to cause ventricular fibrillation (0.5mA cm−2 in the heart), except in a few cases where electrodes were specifically placed to span the heart. When electrodes were placed in positions normally used in whaling operations, no current densities were produced which would have been sufficient to cause brain and cardiac dysfunction.
Further investigations on changes in current density with time post mortem after application of a controlled current of 5A showed, during a 60 hour period, a fourfold increase in the current density in the heart, and more than a twofold increase in the brain. Thus contrary to previous criticisms, if these studies had been carried out on live animals, all current densities would have been below threshold values.
There are no records of signs of epileptic form seizure, which are associated with an effective electrical stun, in whales subjected to the electric lance.
It is concluded that the electric lance as used in whaling operations is ineffective and likely to cause extra pain and suffering to an already distressed animal.