Some Experiments on Navigation in the Harbour Seal, Phoca vitulina

Abstract

Seals, captured on Sable Island (43° 55’ N; 60° 00’ W) and released 24 h later in the interior of the island from places with which they are not familiar and from which the sea is not visible, head SSW on the shortest route to the coast. They do so irrespective of the direction from which the sound of the surf is most clearly audible. Seals prevented from seeing the normal pattern of polarized light, but with their vision otherwise unimpaired, head SSW if the surf is clearly audible anywhere in the southern hemisphere, but go due north into the dunes when the sound of the surf comes from the north. Blindfold animals head in the direction of the sound of the surf. Deaf seals go due north or due south: they are unable to discriminate the seaward from the non-seaward hemisphere even under sunny skies, and they cannot determine the shortest path to the sea even when they do go south. Anosmic seals behave normally.