ASSESSMENT OF THE HUMANE ASPECTS OF ELECTRIC LANCING OF WHALES BY MEASUREMENT OF CURRENT DENSITIES IN THE BRAIN AND HEART OF DEAD ANIMALS

The potential physiological effects of the electric lance are assessed , as used in Japanese whaling operations. Current densities are measur ed in the brains and hearts of six whales to which a controlled curren t of 5 A is applied by two electrodes inserted at various sites in the carcasses, The whales vary in size from 1.8 m (200 kg) to 16 m (40 t) . The minimum current density in the brain necessary to cause depolari sation of neurones is estimated to be 10 mA cm(-2) and to cause ventri cular fibrillation is estimated to be 0.5 mA cm(-2). No current densit ies exceeding 4.8 mA cm(-2) are recorded in the brain. Very few record ings of current density from the heart are above 0.5 mA cm(-2), and th ey occurr only when electrodes are in optimal positions. When electrod es are placed as in whaling operations, no whale over 3 m in length wo uld receive current densities in the heart or brain sufficient to caus e permanent dysfunction. It is concluded that electric lancing is inef fective as a secondary method of killing whales and that the current d ensities recorded could cause pain and suffering to an already distres sed animal.