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The Black Drum Pogonias cromis population in the Upper Laguna Madre (ULM), Texas, USA, is known to exhibit regionally unique population dynamics and life history strategies in comparison with other populations. I examined regional variation in nursery habitat suitability for Black Drum on the Texas coast and further identified functionality of habitat variables in the ULM as it is related to the unique population dynamics observed in this bay system. Rank and relative importance of habitat variables for Black Drum in other regions of the Texas coast were found to differ from those for the ULM population. Furthermore, directionality of salinity and inlet distance differed in the ULM, indicating that increased recruitment in this system was tied to salinities greater than 40‰ and areas at the greatest distance from Gulf of Mexico inlets (i.e., Baffin Bay). Peak mortality and growth rates were found to occur at approximately the same mean salinity value (33‰), with decreases in both as salinity increased. Temperature and dissolved oxygen also exhibited quantifiable relationships with vital rates, although the salinity relationships were most striking. The relationship between growth, mortality, and CPUE suggested that observed recruitment of Black Drum in the ULM is a complex interaction between suitable habitat (hydrographic variables) and density dependence. The identification of regional variation in habitat relationships and the quantification of habitat functionality are crucial steps in interpreting population dynamics and formally incorporating such metrics into stock assessment. This movement from concept to quantification is key to making habitat protection and restoration a true priority in the fisheries management realm.

From 2006 to 2014, Texas Parks and Wildlife Department (TPWD) personnel collected size and maturity data from female blue crabs Callinectes sapidus in all bays along the Texas coast as part of a routine fishery‐independent monitoring program. Logistic regression revealed that coastwide size at maturity was negatively impacted by salinity but that temperature had no effect. More specifically, the model estimated that coastwide size at 50% maturity was 130.5 mm at 0‰, 124.4 mm (122.7–126.0) at 10‰, 118.2 mm (117.1–119.3) at 20‰, and 112.1 mm (110.6–113.5) at 30‰. Size at maturity was found to vary substantially among bay systems in addition to the impact of environmental variables on this relationship. Finally, the logistic curve for size at maturity was found to significantly differ from a similar study (conducted by TPWD personnel; 1984 to 1987) due to higher proportions of mature crabs at smaller size‐classes in the 2006 to 2014 data set. This had a small effect on the size at 50% maturity metric, which was found to have decreased 4 mm between these two eras. Regardless of the driver behind these trends, the present analysis and explicit comparison of these results to a previous study suggests that blue crabs along the Texas coast are highly plastic in terms of size at maturity, especially spatially. Coupled with decadal declines in blue crab populations, these results may justify conservative regulation by state management agencies in terms of female spawner protection. Received December 21, 2015; accepted April 26, 2016 Published online August 12, 2016

The gulf menhaden Brevoortia patronus is an important species of the coastal ecosystem and the target of the largest fishery by landings in the Gulf of Mexico. Menhaden species forage on a variety of plankton and detritus and, by grazing plankton stocks, may provide an important regulatory ecosystem service by reducing organic material loadings. This study used stable isotope analysis to examine the spatial, temporal, and ontogenetic dynamics of food selectivity and trophic role observed in gulf menhaden. The most important dietary item for juvenile (<100 mm total length) fish was phytoplankton (74.0% dietary composition), while that of subadults (100−200 mm) and adults (> 200 mm) was zooplankton (61.6% for sub-adults and 52.4% for adults). Juvenile fish also utilized detritus when present in the water column, and their diet was more varied among individuals than sub-adult and adult age classes. Juveniles occupied a trophic level approximately one step lower (2.65 ± 0.31; mean ± SE) than sub-adults (3.50 ± 0.21) and adults (3.39 ± 0.19). Spatial dietary variation was related to known ontogenetic habitat shifts (i.e. onshore to offshore stratification of size classes), while temporal variation was minimal, especially in the larger size classes. Since the fishery largely targets age 1+ fish (sub-adults and adults), these results suggest that if overfishing occurs to the extent that it impacts recruitment, it may decrease the resiliency of the inshore Gulf of Mexico ecosystem to eutrophication by decreasing the abundance of juvenile fish seasonally present in this environment.