A new Reef Site in Coral Reefs (Green and Cote 2009) describes the striking densities of non-native lionfish on coral reefs in the Bahamas. Lionfish (Pterois volitans), a predator from the central and western Pacific ocean, were first sighted in 1992 off Florida and have been spreading rapidly throughout the Caribbean (USGS Nonindigenous Aquatic Species Database 2009).
On deep offshore reefs off of North Carolina, they are now the second most abundant fish (Whitfield et al. 2007).
From Green and Cote (2009): At three sites, each separated by more than 1 km, we found >390 lionfish per hectare (mean ± 1 SD; 393.3 ± 144.4 lionfish ha−1, n = 4 transects per site). These densities are more than 18 times higher than those reported by Whitfield et al. (2007) from invaded habitats off the coast of North Carolina, USA (21.2 ± 5.1 ha−1)… Caribbean sightings have now been confirmed as far west as Cuba and the Cayman Islands and southeast to St. Croix.
Read more about lionfish here
Green, S. J., and I. M. Cote. 2009. Record densities of Indo-Pacific lionfish on Bahamian coral reefs. Coral Reefs 28:107-107
Whitfield, P. E., J. A. Hare, A. W. David, S. L. Harter, R. C. Munoz, and C. M. Addison. 2007. Abundance estimates of the Indo-Pacific lionfish Pterois volitans/miles complex in the Western North Atlantic. Biological Invasions 9:53-64.