Population ecology and genetics of the invasive lionfish in Puerto Rico

Carlos Toledo-Hernández

doi:10.3391/ai.2014.9.2.12

Abstract

The lionfish (Pterois volitans), has become an abundant alien species along the southeast coast of the United States of America and in Caribbean coastal waters. Although, they represent a major concern in conservation, no studies have yet assessed their population ecology and genetic structure simultaneously. We collected 227 lionfish from 24 sites around Puerto Rico to investigate, the length distribution, length-weight relationships, relative condition factor, and mitochondrial DNA (mtDNA) genetic diversity. The total length distribution ranged between 37 and 349 mm with a single peak between 130 and 149 mm. Our analysis indicated isometric growth for mature individuals and a positive allometric growth for immature lionfishes. These results suggest a different allocation of resources, most likely reproduction for mature individuals and somatic growth for the immature lionfish. The relative condition factor (KN) was similar for immature and mature individuals. Genetic analyses indicated that P. volitans is the only lionfish species present in Puerto Rico, and that its origin was likely dispersal from the epicenter of introduction off the coast of Florida. Interestingly, only four of the nine mtDNA haplotypes identified in the Atlantic were observed in the Puerto Rican population. A fine-scale population genetic analysis suggested a significantly different population structure between the west and south coasts. Finally, our data suggests a second founder effect, but with a reduction of haplotype diversity.

Highlights

Biological invasions are the second major cause of biodiversity loss after habitat degradation (Lowe et al 2000; Stachowicz et al 1999)
Lionfish distribution was assessed through presence/absence surveys conducted at 24 locations around Puerto Rico, from July 2010 to October 2011 (Figure 1; Table 1S)
The length distribution is not normal (Shapiro-Wilk test W=0.959, P

Summary

Introduction

Biological invasions are the second major cause of biodiversity loss after habitat degradation (Lowe et al 2000; Stachowicz et al 1999). They cause alterations in ecosystem functions that may result in significant economic losses (Pimentel et al 2005). In comparison to terrestrial and freshwater habitats (Carlton 1999; Drake et al 1989), biological invasions have been poorly documented in tropical and subtropical marine ecosystems (e.g., Baltz 1991; Randall 1987). Just along the coastal waters of Florida, at least 31 alien marine reeffish species have been reported over the last 6 years (Semmens 2004; Schofield 2009). The inability to visually differentiate between the two lionfish species has precluded a precise report of their distributions

Methods

Results

Conclusion