Effects of Common Angler Handling Techniques on Florida Largemouth Bass Behavior, Feeding, and Survival

Abstract

Black bass Micropterus spp. support popular freshwater sport fisheries in North America. Bass anglers commonly adopt catch and release as a conservation practice, and frequently over 75% of angled black bass are released back into the water. If fish survive the angling event, the practice of catch and release as an alternative to harvest reduces direct mortality, but it has the potential to affect the postrelease feeding behavior and survival of the fish. The act of lifting black bass for handling, hook removal, and photograph opportunities may cause stress and injury, and the degree of injury sustained could be influenced by fish size. Holding fish in a tilted grip by the jaw has raised concern among anglers about potential damage to jaw musculature and tendons, as they may not support the fish’s body weight out of water, particularly for trophy bass. We conducted an experiment with Florida Largemouth Bass M. salmoides floridanus to evaluate the relative differences in survival, jaw mechanics, and feeding success after the use of three common handling treatments: (1) a vertical hold using a lip-grip device (vertical treatment); (2) a tilted, one-handed grip using only the lower jaw (horizontal treatment); and (3) two-handed support to the lower jaw and body (support treatment). The time taken by fish to regain equilibrium and resume normal swimming behavior after handling differed among the three treatments; the recovery period was shortest for fish in the support treatment (mean ± SD = 7 ± 10 s; vertical treatment: 33 ± 74 s; horizontal treatment: 12 ± 16 s). Minor injuries (e.g., abrasions and sores) and diseases (e.g., tumors and fungus) tended to increase after handling across the entire sample. Results suggested no evidence of handling-specific differences in fish feeding behavior, jaw adjustments, and mortality after release. However, based on our results, we recommend that anglers use two-handed support to handle Florida Largemouth Bass, thus minimizing the mean amount of time for an individual fish to regain equilibrium after an angling event.

Received February 22, 2016; accepted October 7, 2016 Published online February 22, 2017

ACKNOWLEDGMENTS

We thank the Florida FWC’s Fish and Wildlife Research Institute for facilities, funding, and support. We are also grateful to the Fisheries Conservation Foundation and the University of Florida for facilities and support. Private donors also provided funding for this study via RocketHub.com: Oregon RFID; Biomark; BassOnline; the Downriver Bass Association (Michigan); the North Toledo Sportsmen’s Club (Ohio); Industrial Automation Services; Craig Bonds; Jojo, Nick, and Katie Sard; James Ludden; Cory Suski; Ryan Swanson; Craig and Debbie Shaw; Andrew Shaw; and Thomas van Gulick. Finally, we appreciate Wes Porak for providing comments on the manuscript and assistance with study design.