Abstract

The present study examined age frequency, growth, mortality, and polycyclic aromatic hydrocarbons (PAH) levels in roughtongue bass, Pronotogrammus martinicensis, from the Pinnacle reefs following the Deep Water Horizon (DWH) oil spill. Two sites were sampled: the Alabama Alps (west) 54 km from the DWH site, and Roughtongue Reef (east) 111 km from the DWH site. Seasonal samples of roughtongue bass were collected in Sep-Oct 2014 (n=190), Dec 2014 (n = 249), Mar 2015 (n = 310) and Jun-Jul 2015 (n = 360). Based on otolith aging (n=1090), resident fish were dominated by the 2009 and 2010 year classes. Von Bertalanffy growth parameters for all fish were L? = 102.2, K = 0.60, and t0 = 0.25. Growth rates were significantly lower for fish from Alabama Alps (n = 873; L? = 100.7, K = 0.93, t0 = 0.80) com-pared to fish from Roughtongue reef (n = 216; L? = 86.3, K = 0.53, t0 = -0.67; p = < .0001), and most likely linked to prox-imity and discharge from the Mississippi River. Total mortality Z = 1.73 and annual survival S = 18% (n = 1090). Polycyclic aromatic hydrocarbons(PAH) had mean = 50 ± 52.2, range = 0 to 220 ppb (n=38), were less than the marine lowest observed effects levels of 300 ppb, and did not differ between collection sites. Based on the dominance by the 2009 and 2010 year classes and low PAH levels, the present study showed no effect of DWH on this mesophotic reef species.

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