Harbour porpoises are among the smallest whales in the world, and Cape Cod National Seashore accounts for the largest share of Massachusetts’ named records, its nearshore waters giving a clear view of an animal that surfaces briefly and quietly rather than breaching like a whale or riding a boat’s wake like a dolphin.
Records peak sharply in March, ease slightly into a May bump, then fall by more than ten-fold heading into summer. That spring-heavy pattern likely tracks porpoises following schooling fish closer to shore before moving to deeper or more northern waters as the season warms, rather than any change in how carefully people were watching.
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