fishing by lost traps is a known cause of lobster mortality in the Florida lobster trap fishery, the sublethal effects of long- term confinement in these traps remains ...
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Bull Mar Sci. 94(0):000–000. 2018 https://doi.org/10.5343/bms.2017.1137
research paper
Sublethal and lethal effects of confinement of Caribbean spiny lobsters, Panulirus argus, in ghost traps Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 2796 Overseas Hwy Suite 119, Marathon, Florida 33050. 1
Department of Biological Sciences, Old Dominion University, Norfolk, Virginia 23529.
Casey B Butler 1 * Benjamin C Gutzler 2 Thomas R Matthews 1
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* Corresponding author email: , phone: + 1 (305) 289-2330, facsimile: + 1 (305) 289-2334.
11th International Conference and Workshop on Lobster Biology & Management · Portland, Maine 4–9 June, 2017 Guest Editors: Kari Lavalli, Richard Wahle Guest Section Editor: Anna Malek Mercer Date Submitted: 31 August, 2017. Date Accepted: 8 February, 2018. Available Online: 12 April, 2018.
ABSTRACT.—Ghost fishing occurs when lost or abandoned fishing gear continues to capture animals, resulting in lethal and sublethal effects. Though ghost fishing by lost traps is a known cause of lobster mortality in the Florida lobster trap fishery, the sublethal effects of longterm confinement in these traps remains largely unknown. Here, we examine the nutritional condition and overall health (e.g., incidence of injuries and disease) via three assays: a field survey to compare nutritional condition and overall health of lobsters in existing ghost traps to natural shelters via blood serum protein (BSP) and hepatopancreas dry weight indices (DWI); a field experiment to monitor the effects of confinement on individual lobsters over time; and a laboratory experiment to simulate starvation and recovery of the BSP of lobsters associated with confinement and escape from traps. Overall, lobsters in existing ghost traps were in poorer nutritional condition, had a higher prevalence of injuries and shell disease, and were lethargic. There was a clear deterioration of the health and increased mortality of lobsters as confinement duration increased in our experimental ghost traps. After 2 wks, BSP of lobsters decreased by 23.7%; lobsters in this poor nutritional condition were less likely to escape and more likely to die in traps. Laboratory experiments indicate that if escape does occur, recovery may be slow or unlikely. Our study highlights the drastic sublethal effects of long-term confinement in ghost fishing traps on lobsters and the need for further research on ways to mitigate these effects.
The issue of “ghost fishing” by derelict (discarded, lost, or abandoned) fishing gear, such as nets or traps, impacts marine environments globally (Matsuoka et al. 2005, NOAA Marine Debris Program 2015). Ghost fishing occurs when derelict gear remains intact, continuing to catch and kill animals (Smolowitz 1978). Animals confined in ghost traps for long periods of time are subject to various stresses, including starvation, injuries, cannibalism, predation, and disease (Guillory 1993). Animals that are able to escape ghost traps may exhibit higher susceptibility to predation and reduced growth rates as a result of latent effects of confinement-induced injuries and stress, as has been seen in Alaska king crabs, Paralithodes camtschaticus (Tilesius, Bulletin of Marine Science
© 2018 Rosenstiel School of Marine & Atmospheric Science of the University of Miami
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Bulletin of Marine Science. Vol 94, No 0. 2018
1815), in ghost fishing crab traps (High and Worlund 1979) and in lobster traps (Hunt and Lyons 1986). The Caribbean spiny lobster, Panulirus argus (Latreille, 1804), fishery is an important component of the culture and history of the Florida Keys and is valuable to Florida’s economy. Lobsters have a commercial dockside value between US$18 and US$50 million annually, and the recreational fishery brings millions of dollars in tourism revenue to the state each year (Sharp et al. 2005). The commercial trap fishery provides about 70% of the landings. In the 2015/2016 fishing season, 472,946 traps were fished, the majority of which were fished in the waters around the Florida Keys (TR Matthews, Florida Fish and Wildlife Conservation Commission, unpubl data). Live, sublegal lobsters (
