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 turn up in every month, but spring is the busiest stretch, with May and March leading and September the quietest month. 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.
Full species profile
