In the Pond Inlet area of Baffin Island in 1963–65, 62 narwhals (Monodon monoceros) were caught in nets and examined. Growth layers occur in both the extruded tusk and in the embedded tooth. The few identifiable food remains in stomachs were of squid and Arctic cod. At birth, the calf measures about 160 cm in length and weighs just over 80 kg. Fully grown females attain a length of 400 cm and a weight of 900 kg. Males reach 470 cm and a weight of 1600 kg. Calving is assumed to occur about once in 3 yr. A conservative estimate for the narwhal population of Canada and northwestern Greenland is approximately 10,000. Although the birth rate is unknown, it is assumed to be similar to that calculated for the closely related white whale; that is, about 9%. The maximum potential annual catch, based on the highest reported Canadian catch of 442 narwhals in 1957, combined with the Greenland catch of 135 and an assumed sinking loss of 50%, is about 1154. This is above the estimated annual production of 900.