Abstract
Invasive species alter ecosystem integrity and functioning and are considered one of the major threats to biodiversity on a global scale. The indopacific lionfish (Plerois volitans [Linnaeus, 1758] / miles [Bennet, 1882] complex) is the first non-native marine fish that has established itself in the Western Atlantic. It was first reported in Florida in the 1980s and then spread across the entire Caribbean in subsequent years. In Costa Rica, lionfish were first sighted by the end of 2008 and are now present in all South Caribbean reefs. Lionfish are a major problem for local fisherman by displacing native fish species. The aim of this study was to determine population density, size and diet of lionfish populations at four study sites along the Southern Caribbean coast of Costa Rica. Two of the sites were located inside the National Park Cahuita where regular lionfish removal occurs, whereas the other two study sides do not experiment this kind of management. Total length and wet weight of >450 lionfish individuals were determined between March and June 2011. Three relative metrics of prey quantity (percent number, percent frequency, and percent weight) were compared from approximately 300 lionfish caught with the polespear in shallow waters (<7 m depth). Population density was assessed weekly through visual transect surveys. Our results showed that lionfish preyed mostly upon teleosts and crustaceans. Teleosts dominated lionfish diet in percent frequency (71%) and percent weight (85%), whereas crustaceans had the highest percent number (58%). The top five teleost families of dietary importance were Pomacentridae, Acanthuridae, Blennidae, Labridae and Serranidae. The average total length (+/- SD) of lionfish was 18.7 (+/- 5.7)cm and varied significantly between sites (p<0.001). Mean density of lionfish was 92fish/ha with no significant differences between sites. Smallest fish and lowest densities were found at the two sites inside the National Park Cahuita. Despite management efforts on a regional scale, nationwide efforts are ineffective and lionfish control activities are poorly implemented. We conclude that there is an urgent need to develop an improved institutional framework for local lionfish control that promotes effective coordination among the relevant stakeholders in order to deal with invasive lionfish in Costa Rica.
Highlights
2005, the Millennium Ecosystem Assessment concluded that the introduction rate continues to be extremely high causing a significant impact on marine biodiversity
In Costa Rica, lionfish were first noted by local fishermen along the Southern Caribbean coast by the end of 2008
It is of primary importance to investigate population density and structure as this allows for assessing the degree of infestation and ongoing population dynamics
Summary
2005, the Millennium Ecosystem Assessment concluded that the introduction rate continues to be extremely high causing a significant impact on marine biodiversity. The Indopacific lionfish (P. volitans/miles complex) was the first marine fish to become established and to convert into one of the key invasive species in the Western Atlantic It was first reported in Florida in the 1980s and spread across the entire Caribbean region, including Mexico, Cayman Islands, Puerto Rico, Belize, Honduras, Colombia and Venezuela (Betancur-R. et al, 2011; Schofield, 2010). It is of primary importance to investigate population density and structure as this allows for assessing the degree of infestation and ongoing population dynamics Another important aspect is to investigate the diet of the lionfish in order to draw conclusions about the most affected species by lionfish predation and to quantify its impacts on forage fish communities. The aim of this study was to determine population density, size and diet of the lionfish populations established along the Southern Caribbean coast of Costa Rica
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
