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AbstractAs coastal human populations increase and offshore fishery regulations become more stringent in the northern Gulf of Mexico, nearshore fisheries may be subjected to increased exploitation. Spanish Mackerel Scomberomorus maculatusand Florida Pompano Trachinotus carolinusare two nearshore, coastal migratory pelagic species vulnerable to undergoing changes in fishing pressure; however, information is incomplete in regards to understanding their current distributions and movement patterns, both of which are important for effective fishery management. We used a 2-year (2011–2012) gill-net and seine survey to assess surf zone distributions of Spanish Mackerel and Florida Pompano in the northern Gulf of Mexico (Horn Island, Mississippi, to Pensacola, Florida). Unbiased catch-per-unit-effort estimates (by the delta method) were greatest in Alabama and during spring months. Lowest catches occurred during the warm summer months. Overall, subadult–adult Spanish Mackerel presence could be predicted (using a delta-lognormal general linear model) by geographic area, beach habitat, and depth. Florida Pompano presence could be predicted by month and beach habitat. For both species, the abundance could not be predicted by any of the examined variables. Juvenile Florida Pompano presence, contrastingly, could be predicted by month and salinity, and abundance by month and water temperature. Both species had spatiotemporal variability in distribution and catch rates, but beach habitat appeared to be a better predictor for subadults and adults of both species, whereas month and salinity were better predictors for juvenile Florida Pompano catches. Greater catches generally corresponded with proposed migration patterns but also suggest that individuals, at least temporarily, leave the surf zone during the day in the warm summer months. Furthermore, although legal-sized individuals of both species can co-occur in the surf zone in the northern Gulf of Mexico, the increase in Spanish Mackerel presence with depth suggests that Spanish Mackerel fisheries could potentially move further offshore to avoid user conflict with Florida Pompano fisheries.Received March 16, 2016; accepted August 1, 2016 Published online October 14, 2016

As coastal human populations increase and offshore fishery regulations become more stringent in the northern Gulf of Mexico, nearshore fisheries may be subjected to increased exploitation. Spanish Mackerel Scomberomorus maculatusand Florida Pompano Trachinotus carolinusare two nearshore, coastal migratory pelagic species vulnerable to undergoing changes in fishing pressure; however, information is incomplete in regards to understanding their current distributions and movement patterns, both of which are important for effective fishery management. We used a 2-year (2011–2012) gill-net and seine survey to assess surf zone distributions of Spanish Mackerel and Florida Pompano in the northern Gulf of Mexico (Horn Island, Mississippi, to Pensacola, Florida). Unbiased catch-per-unit-effort estimates (by the delta method) were greatest in Alabama and during spring months. Lowest catches occurred during the warm summer months. Overall, subadult–adult Spanish Mackerel presence could be predicted (using a delta-lognormal general linear model) by geographic area, beach habitat, and depth. Florida Pompano presence could be predicted by month and beach habitat. For both species, the abundance could not be predicted by any of the examined variables. Juvenile Florida Pompano presence, contrastingly, could be predicted by month and salinity, and abundance by month and water temperature. Both species had spatiotemporal variability in distribution and catch rates, but beach habitat appeared to be a better predictor for subadults and adults of both species, whereas month and salinity were better predictors for juvenile Florida Pompano catches. Greater catches generally corresponded with proposed migration patterns but also suggest that individuals, at least temporarily, leave the surf zone during the day in the warm summer months. Furthermore, although legal-sized individuals of both species can co-occur in the surf zone in the northern Gulf of Mexico, the increase in Spanish Mackerel presence with depth suggests that Spanish Mackerel fisheries could potentially move further offshore to avoid user conflict with Florida Pompano fisheries. Received March 16, 2016; accepted August 1, 2016 Published online October 14, 2016

Spanish Mackerel Scomberomorus maculatussupport important commercial and recreational fisheries in the Gulf of Mexico (GOM). Although federally managed because of interstate migrations, harvest, essential fish habitat consideration, and management are largely state issues. Contrary to the accepted paradigm of a well-mixed stock from the GOM to the Atlantic, Spanish Mackerel have been suggested to exhibit reduced movement, and hence mixing, which could lead to areas of localized depletion within the larger stock. We addressed how local abundance patterns responded to changes in harvest pressure, evaluated migration patterns via examining temporal trends in abundance, and determined whether the spatial abundance patterns resembled habitat specialization or generalization. Abundance trends of Spanish Mackerel in Alabama have remained relatively constant from 2001 to 2011 despite a significant increase in commercial harvesting. Seasonal patterns of catch rates coincided with the proposed annual migration. We also observed adult Spanish Mackerel in low salinities (0–10‰) at the mouth of Mobile River during the fall when river discharge is relatively low. This extends the known range of estuarine habitat use by adult Spanish Mackerel. Because Mobile Bay includes various habitat types differing from surf zone and coastal ocean habitats typically inhabited by Spanish Mackerel, capturing Spanish Mackerel near the mouth of Mobile River provides evidence for a habitat generalist strategy. Based on a relatively constant abundance index and year-class strength, the stock seems to be relatively stable even after a drastic increase in commercial harvests in Alabama and heavy exploitation of age-1–3 Spanish Mackerel. The resilience of catch rate trends to changes in local harvest pressure as well as evidence of synchrony among areas in terms of migration suggest the Alabama fishery is influenced by population dynamics of a larger population. Received July 3, 2014; accepted January 12, 2015

AbstractSpanish Mackerel Scomberomorus maculatussupport important commercial and recreational fisheries in the Gulf of Mexico (GOM). Although federally managed because of interstate migrations, harvest, essential fish habitat consideration, and management are largely state issues. Contrary to the accepted paradigm of a well-mixed stock from the GOM to the Atlantic, Spanish Mackerel have been suggested to exhibit reduced movement, and hence mixing, which could lead to areas of localized depletion within the larger stock. We addressed how local abundance patterns responded to changes in harvest pressure, evaluated migration patterns via examining temporal trends in abundance, and determined whether the spatial abundance patterns resembled habitat specialization or generalization. Abundance trends of Spanish Mackerel in Alabama have remained relatively constant from 2001 to 2011 despite a significant increase in commercial harvesting. Seasonal patterns of catch rates coincided with the proposed annual migration. We also observed adult Spanish Mackerel in low salinities (0–10‰) at the mouth of Mobile River during the fall when river discharge is relatively low. This extends the known range of estuarine habitat use by adult Spanish Mackerel. Because Mobile Bay includes various habitat types differing from surf zone and coastal ocean habitats typically inhabited by Spanish Mackerel, capturing Spanish Mackerel near the mouth of Mobile River provides evidence for a habitat generalist strategy. Based on a relatively constant abundance index and year-class strength, the stock seems to be relatively stable even after a drastic increase in commercial harvests in Alabama and heavy exploitation of age-1–3 Spanish Mackerel. The resilience of catch rate trends to changes in local harvest pressure as well as evidence of synchrony among areas in terms of migration suggest the Alabama fishery is influenced by population dynamics of a larger population.Received July 3, 2014; accepted January 12, 2015