The effect of wind direction on flying fish counts

Abstract

Flying fish and squid flushed by a ship's passage are easy to count, but the value of such data is compromised by uncertainty regarding the proportion of individuals flushed. Wind direction relative to the ship's course plays an important role in determining this proportion, with on average 6 times (range 2.5–10.8) more fish flushed on the windward side of the ship when there are moderate to strong cross winds. As a result, counts of flying fish that cover only one side of a ship's bow should sample the windward side.