Vol. 24: 219–226, 2016 AQUATIC BIOLOGY Published online April 19 doi: 10.3354/ab00651 Aquat Biol OPENPEN ACCESSCCESS Density, size, biomass, and diet of lionfish in Guanahacabibes National Park, western Cuba Dorka Cobián Rojas1, Pedro Chevalier Monteagudo2, Juan J. Schmitter-Soto3,*, Raúl Igor Corrada Wong2, Héctor Salvat Torres4, Erlán Cabrera Sansón4, Alain García Rodríguez5, Alexis Fernández Osorio2, Leonardo Espinosa Pantoja6, Delmis Cabrera Guerra2, Laura María Pantoja Echevaria2, Hansel Caballero Aragón2, Susana Perera Valderrama7 1Parque Nacional Guanahacabibes, Centro de Investigaciones y Servicios Ambientales, Ministerio de Ciencia, Tecnología y Medio Ambiente, La Bajada, 22100 Pinar del Río, Cuba 2Acuario Nacional de Cuba, Calle 1ª #6002, 11300 Playa, Havana, Cuba 3El Colegio de la Frontera Sur, Av. Centenario km 5.5, 77014 Chetumal, Mexico 4Formerly at Instituto de Oceanología, Ave. 1a #18406, CP 11600 Havana, Cuba 5Instituto de Oceanología, Ave. 1ª #18406, CP 11600 Havana, Cuba 6Parque Nacional Cayos de San Felipe, 20100 La Coloma, Pinar del Río, Cuba 7Centro Nacional de Áreas Protegidas, Calle 18A #4114, 11300 Miramar, Playa, Havana, Cuba ABSTRACT: The Indo-Pacific lionfish Pterois volitans is an invasive species that was first recorded in the Guanahacabibes National Park (GNP), a marine protected area in western Cuba, in 2009. In order to determine the invasion progression of this species, we studied lionfish abundance, size, and diet at 6 sites in the GNP between 2010 and 2014. The species’ density, biomass, and length increased over this period, probably due to the abundance of food and shelter in the GNP. Analy- sis of stomach contents indicated that lionfish fed primarily on fish and crustaceans; main prey were teleosts, predominantly Gobiidae, Pomacentridae, Mullidae, Labridae, Scaridae, and Gram- matidae. This example of a rapid increase in an unmanaged population at the onset of invasion provides information that can be used to design a management program targeting lionfish. KEY WORDS: Invasive species · Marine protected area · Reef habitat · Fish · Scorpaenidae · Pterois volitans INTRODUCTION Mooney 2007). The main environmental impacts caused by these species are degradation of habitats, Invasive alien species are those introduced species ecosystem imbalances, displacement and extinction that become established in natural or semi-natural of native flora and fauna, disruption of trophic struc- ecosystems and constitute an agent of change and ture, facilitation of subsequent invasions, and disease threat to the native species and biological diversity of transmission (Gutiérrez 2006, Pyšek & Richardson the region (Mendoza & Koleff 2014). They are typi- 2010). Populations of invasive species may actually cally introduced in a voluntary or accidental manner, increase faster and achieve higher densities in the mediated by human action (Gutiérrez 2006). In re - invaded area than in their original habitat (Cox cent decades, the prevalence of invasive species has 2004). The reasons for the success of these biological increased in both terrestrial and marine environ- invasions are not simple; they depend on the traits of ments, reaching unprecedented levels (Meyerson & the ecosystems themselves (e.g. habitat complexity; © The authors 2016. Open Access under Creative Commons by *Corresponding author: [email protected] Attribution Licence. Use, distribution and reproduction are un - restricted. Authors and original publication must be credited. Publisher: Inter-Research · www.int-res.com 220 Aquat Biol 24: 219–226, 2016 Alexander et al. 2015), as well as on the inherent area have allowed a significant increase in the lion- characteristics of the invading species (Mendoza & fish population. Koleff 2014). Studies of biological invasions have a long tradition; however, literature on the subject has only increased significantly since the 1990s (Pyšek & MATERIALS AND METHODS Richardson 2010). From this perspective, invasion biology is still a very young discipline (Pyšek & Study site Hulme 2009). The establishment of Indo-Pacific lionfish Pterois GNP was established as a marine protected area in volitans populations in the western Atlantic is the 2001 and encompasses 39 830 ha (including land) in utmost example of a marine fish invasion (Ruiz-Carus the westernmost region of Cuba, from Cabo Corrien - et al. 2006). Schofield (2010) described the timing of tes (21° 45’ N, 84° 30’ W) to the site known as Verraco the invasion. In Cuba, lionfish were first recorded in (21° 91’ N, 84° 61’ W). The fringing coral reefs in GNP 2007 off the north coast east of Havana and in the form a single terrace, with isolated coral heads but southeast near Santiago (Chevalier et al. 2008). Since no well-defined crest. The sandy terrace ends at 12 that time, lionfish have thoroughly and swiftly to 20 m at a deep drop-off, which is composed of a invaded the area, taking only 1.5 yr to reach the varied and often quite complex architecture. Orbicella, westernmost tip of Cuba. The first sightings of lion- Agaricia, Porites, and Siderastrea dominate the coral fish occurred in Guanahacabibes National Park community (González-Ferrer et al. 2007). (GNP), western Cuba, in 2009. This invader can now be found in mangroves, seagrass prairies, and coral (Cobián et al. 2013). As observed elsewhere in the Underwater visual censuses and lionfish sampling region, this invasion success is attributable to its dis- persal mode, fecundity, and feeding habits, as well as Underwater visual censuses were conducted at 6 a lack of natural predators (Layman & Allgeier 2012). sites (Fig. 1) during Dec 2010, Sep 2011, Apr 2012, Darling et al. (2011) and Morris (2009) suggest that Jun 2013, and Feb 2014 in the front reef, from the the biological and ecological characteristics of lion- edge of the drop-off to 25 m along the wall. Sampling fish have allowed their populations to achieve higher habitats were classified as drop-off (Cuevas de Pedro, densities in invaded regions than in their native habi- Encanto, Yemaya and Uvero Quemado) or spur-and- tats; e.g. in the Bahamas, the species has reached groove (Veral and Verraco). All surveys were con- densities >0.039 ind. m–2 (Green & Côté 2009), much ducted between 15 and 25 m depth. At every site, 6 higher than e.g. in their native Palau (0.000022 ind. linear transects (50 m long, 2 m wide) were surveyed, m–2; Grubich et al. 2009). according to Brock (1954). Individual lionfish were Ours is the first study related to lionfish autoeco - carefully sought in cracks, caves, and hollows. The logy in western Cuba. This research is relevant not size of every lionfish sighted was visually estimated only because of its novelty for the area, but also to the nearest cm, and the total weight of individuals because there are few (if any) cases where this type was calculated employing length− weight equations of research has been conducted in strictly non-fished ob tained for Cuban waters (P. Chevalier unpubl. areas. In the GNP, the ecosystem is healthy and well- data), equation parameters a = 0.012 and b = 3.017. conserved; richness is high for corals, fishes, and We calculated the density (ind. m−2) and biomass other groups (Cobián & Chevalier 2009). Similarly, (g m−2) of lionfish for every transect and averaged coral reefs in GNP lack any human impact since no these variables for every site. commercial or recreational fishing is practiced in the Lionfish were collected at 8 sites in June 2013 and area, and there is no pollution. The complete absence June 2014 (Fig. 1), following sampling and process- of management against lionfish in GNP (until 2015) ing protocols outlined by Chevalier et al. (2014). makes these data an important reference for com - Specimens were collected with hand nets or spears. parisons throughout the region. Dissections were performed on 411 freshly caught The aim of this article was to determine the pro- specimens. Individual prey items in lionfish stomachs gression of density, biomass, and individual size of were identified to the lowest taxon possible; fish lionfish in GNP between 2010 and 2014. Compared identification was based on Guitart (1985) and Hu - to the invasion patterns of lionfish in other countries mann & DeLoach (2002); crustaceans were identi- (Morris & Akins 2009, Schofield 2010, Green et al. fied based on Martínez-Iglesias & Gómez (1986) and 2012), we believe that the favorable conditions of this Ortiz et al. (2010). Cobián Rojas et al.: Lionfish density, size, biomass and diet in Cuba 221 Fig. 1. Survey and col- lection sites for lion- fish within Guanaha- cabibes National Park, Cuba Data analyses ber 2011 mean densities for all GNP sites reached ≥0.05 ind. m−2. Density continued to increase at all Data were tested for normality (Shapiro-Wilk sites during the first 2 to 3 yr after the initial invasion test) and homoscedasticity (Levene’s test) and were in 2009, leveling off around 2013. Density was high- found to have a normal distribution and homogeneity est in the drop-off habitats, at Veral and Verraco of variance, so no transformation was necessary. Re - (Fig. 2). Total length of individuals also in creased peated-measures ANOVA was conducted on the steadily until at least 2012 (Fig. 3) subsequently lev- density, biomass and size of lionfish by site; to deter- eling off; biomass also increased, in some sites until mine the trend over time, an average of these vari- 2013, leveling off or, in some sites, decreasing after- ables was calculated with the values of the 6 sites for wards (Fig. 4). On average, density, biomass, and size each sampling date. Significance was assessed at α = in creased significantly during the first years of the 0.05; a Student-Newman-Keuls test was performed invasion; afterwards density decreased and the other when differences were significant. Statistical analy- variables leveled off (Fig. 5). ses were conducted using Statistica v. 8.0 (StatSoft). Of the 411 lionfish stomachs examined, 67 (16.3%) Diet analysis combined calculations of relative were empty.