Swept-Away Sailfish

Q: While fishing an offshore canyon in August, we caught a dozen 3- to 5-pound dolphin. When we cleaned them, we found these two semi-digested, 8-inch fish in their stomachs. Are they immature billfish or some kind of baitfish? - Keith Anderson, Barnegat Light, New Jersey

A: From the length of their bills and the size of their dorsal fins, your dolphin appetizers appear to be two young sailfish. Juvenile sailfish stay near the surface, hiding around floating objects such as seaweed. That's a favorite feeding spot for school dolphin - so small sailfish are not uncommon in dolphin's stomachs.
Western Atlantic sailfish spawn in the spring, from Florida to Venezuela. Since the young of any species do not swim strongly, the powerful northbound Gulf Stream current catches many and may carry them to distant regions such as New England or even farther north. (Even tropical angelfish have sometimes ended up off New York.)
According to billfish age-and-growth specialist Eric Prince of the National Marine Fisheries Service, an 8-inch sailfish is probably one-and-a-half to three months old, depending on whether you're measuring the length including the bill or just the lower-jaw/fork length. That's plenty of time for young sailfish caught in the Gulf Stream to be swept from spawning grounds off Florida north to New Jersey.