What Seafood Menus Reveal About Hawaii's Changing Seas

Scientists used historic menus to fill in four decades of missing records.

Old restaurant menus—like this 1958 menu from Trader Vic's in Honolulu, Hawaii—can reveal data about wild fish populations.

Vacationers who took Hawaiian restaurant menus home as souvenirs recently helped piece together a 45-year gap in the state's fishing records.

The menus were used as a data source by several researchers, including Kyle Van Houtan, a researcher at the National Oceanic and Atmospheric Administration's Pacific Islands Fisheries Science Center. Van Houtan and his colleagues tracked changing fish populations near the Hawaiian islands based on which fishes appeared on menus during the early and mid-20th century.

Their research, which was recently published in Frontiers in Ecology and the Environment, found correlations between menu items and what local fishing data do exist—which may be able to fill in gaps for the four decades that lack local commercial fishing numbers.

"The menus mimic more than just consumer preference," Van Houtan said. "They also show us what's happening in the ocean."

Van Houtan and his colleagues found that some reef fish—like groupers, mullets, and flounders—were highly prevalent before 1940 before becoming more rare after World War II. Larger, offshore fish and farm-grown fish, meanwhile, rose in popularity as local fishing catches declined and improvements were made in fishing technology.