Influence of Age‐1 Conspecifics, Sediment Type, Dissolved Oxygen, and the Deepwater Horizon Oil Spill on Recruitment of Age‐0 Red Snapper in the Northeast Gulf of Mexico during 2010 and 2011

Abstract

The Deepwater Horizon oil spill was one of the largest oil spills in U.S. history. The timing of this spill coincided with peaks in spawning and recruitment of Red Snapper Lutjanus campechanus and may have led to reduced recruitment or to year‐class failure. Artificial recruitment reefs were deployed in 2010 (n = 30) and 2011 (n = 30) to measure Red Snapper recruitment off the coast of Alabama at four sites (three inshore sites, 13 km south: west, center, and east sites, each 30 km apart; and one offshore site, 25 km south). Substantial age‐0 Red Snapper recruitment (density range = 0–34.5 fish/m3) occurred in 2010, with higher densities on inshore reefs than on offshore reefs. Age‐0 Red Snapper recruitment was again observed in 2011 (density range = 0–108.5 fish/m3) along with age‐1 Red Snapper (density range = 0–78.9 fish/m3) from the 2010 year‐class. There was a negative correlation between the densities of age‐0 and age‐1 Red Snapper, indicating that older Red Snapper excluded younger fish from the reefs. Higher fractions of silt in the substrate at the west site compared with the center and east sites were associated with higher densities of age‐0 Red Snapper, but the effects of sediment type were less important than exposure to hypoxic conditions at the west site in late August 2011 (dissolved oxygen fell to concentrations as low as 0.4 mg/L), which caused an almost complete loss of fish. The abundances of age‐0 and age‐1 Red Snapper in 2010 and 2011 provide evidence that the oil spill did not result in a year‐class failure and that the most important variables affecting age‐0 Red Snapper abundances were age‐1 Red Snapper presence and dissolved oxygen concentration. Received August 23, 2013; accepted December 19, 2013

Change and recovery of coastal mesozooplankton community structure during the Deepwater Horizon oil spill

“…There is evidence to suggest that zooplankton can detect and possibly avoid areas with high concentrations of hydrocarbons [5,31]. Much of the oil in our sampling region was observed at the surface [32,33], [34]. Previous observations from the Gulf of Mexico 'dead zone' suggest mesozooplankton also migrate to avoid hypoxic waters [35].…”

Environmental and Structural Drivers of Fish Distributions among Petroleum Platforms across the U.S. Gulf of Mexico

“…The DO concentration influenced the probability of encounter of Red Snapper in both the horizontal and vertical dimensions (Tables ). Previous studies of Red Snapper ecology in nonplatform habitats indicated that DO concentration had a moderate to large effect on the abundance and horizontal distribution of this species (Szedlmayer and Shipp ; Szedlmayer and Mudrak ; Switzer et al. ).…”

Environmental effects of the Deepwater Horizon oil spill: A review

“…Similarly, there were no significant differences in recruitment of marsh-associated resident and transient nekton in AL salt marshes following the DWH spill (Moody et al, 2013). There was also little effect of the spill on recruitment of red snapper (Lutjanus campechanus) to multiple artificial reefs in NGOM (Szedlmayer and Mudrak, 2014). In 2010 and 2011, there were no year-class failures, and age-0 class abundance was determined primarily by the presence of age-1 individuals and concentrations of dissolved oxygen.…”