Are canned sardines or dry cat food more effective as bait for capturing Northwestern Pond Turtles (Actinemys marmorata) and Red-eared Sliders (Trachemys scripta elegans)?

During an occupancy study of Northwestern Pond Turtles (Actinemys marmorata) and Red-eared Sliders (Trachemys scripta elegans) in California’s Sacramento Valley in 2018, we tested the relative effectiveness of 2 bait types: sardines packed in soybean oil and Meow Mix^® Original Choice dry cat food. We sampled 116 sites with 2 traps each: one baited with sardines and one baited with dry cat food. Sardines were 1.7 (95% confidence interval, 1.2–2.6) times more effective than dry cat food at capturing turtles in our study, and 63% of all captured turtles were caught in traps baited with sardines. Despite the slightly lower capture rate in traps baited with dry cat food, the significantly lower cost of cat food (about one-tenth the cost of sardines) makes it an appealing alternative bait if cost-effectiveness is a primary concern.