APPLICATION OF REMOVAL SAMPLING TO ESTIMATE THE DENSITY OF RINGED SEALS (PHOCA-HISPIDA) IN BARROW STRAIT, NORTHWEST-TERRITORIES

A dog survey technique was adapted to removal sampling, where seal holes located under the snow by the dogs during surveys of fixed effort were marked and treated as removals from the population. Computer simulation indicates that estimates of seal hole density are within 10% of the true population size if for each plot there are ≥4 searches, sampling intensity is ≥0.85, the coefficient of variation of the estimate is ≤0.3, and the probability of detecting a seal hole intensity is ≥0.35. Densities of sea holes varied from 4.8-7.9 holes.km-2. Eight seals had an average hole to seal ratio of 3.4. Seal densities ranged from 1.4-2.3 seals.km-2, and may be much higher if pup production is included. -from Authors