The effect of salinity on behavioural interactions between native Schoolmaster snapper (Lutjanus apodus) and invasive lionfish (Pterois spp)

• Published in: Journal of experimental marine biology and ecology Vol. 530-531; p. 151414
• Main Authors: Trehern, Rebekah H., Raguse, Cameron, Bigelow, William F., Garg, Aneri, Hauptman, Hannah, Brooks, Annabelle, Van Leeuwen, Travis E., Hawkes, Lucy A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2020
• Subjects: Back-reef ecosystems; Invasive species; Lionfish; Mangroves; Salinity; Back-reef ecosystems; Mangroves; Invasive species; Lionfish; Salinity
• ISSN: 0022-0981; 1879-1697
• DOI: 10.1016/j.jembe.2020.151414

Species invasions are a widely-recognized threat to regional and global biodiversity. Lionfish (Pterois spp.), are an invasive marine fish that have been shown to reduce the recruitment and biomass of native reef fish throughout the Caribbean. Recently, it has become clear that lionfish are able to colonise a wide range of ecosystems (mesophotic reefs to brackish estuaries to mangroves) and tolerate a wider range of salinities than previously thought. Estuarine ecosystems often experience hyposaline conditions and act as critical foraging habitats for many ecologically and economically important species. Using a habitat competition experiment at two salinity treatments (10 practical salinity units (psu) and 37 psu control) we investigated the potential effects of lionfish on native Schoolmaster snapper (Lutjanus apodus; a tropical fish species found in high abundance in estuarine ecosystems). Schoolmaster snapper showed a 62% and 47% reduction in cover use when in the presence of lionfish in the 10 psu and 37 psu treatments, respectively. Further, five of the seven behaviours investigated during the interaction period, where both lionfish and snapper had access to the shelter, showed a significant reduction at low salinity, suggesting physiological or behavioural impairment of lionfish at low salinity. Because estuarine habitats are disproportionately important habitats for juvenile fishes, even physiologically or behaviourally compromised lionfish are likely to have some impact. •Lionfish sheltering behaviour is unaffected in hyposaline conditions.•Lionfish competitive ability decreases in hyposaline conitions.•Schoolmaster snapper shelter less in the presence of lionfish•Lionfish may outcompete native estuarine fish species for shelter.