Effect of Water Temperature on Food Evacuation Rate and Feeding Activity of Age-0 Gizzard Shad

Abstract A study was conducted to evaluate the influence of water temperature on food evacuation and feeding activity in age-0 gizzard shad Dorosoma cepedianum fed pulverized food. Fish kept at 5°C exhibited little feeding activity. At temperatures of 10, 15, and 20°C, food was evacuated through the digestive tract in 8.5, 4.9, and 4.4 h, respectively. Frequency of feeding acts also increased significantly with increased water temperature. These data, along with information on the dry weights of natural detritus in full digestive tracts of gizzard shad (ages 0–2) from Acton Lake, Ohio, were used to estimate the daily amounts of natural detritus consumed by age-0 fish. We concluded that a 6-g, age-0 fish can ingest and process natural detritus (dry weight) in amounts ranging from 3.2 to 7.7% of wet body weight per day.