Fiorello LaGuardia, mayor of New York City, posing with a 300-pound halibut at the Fulton Fish Market in 1939. By this time giant halibut - common in the North Atlantic at the time the Jamestown colony was founded in Virginia in the early 17th century - had become scarce

Photograph: C. M. Stieglitz, New York World-Telegram & Sun Collection, Libraryt of Congress.