Declines in shark populations have sparked researchers and fishery managers to investigate more prudent approaches to the conservation of these fish. As managers strive to improve data collection for stock assessment, fisheries‐independent surveys have expanded to include data‐deficient areas such as coastal regions. To that end, a catch series from a nearshore survey off Alabama was combined with data from a concurrent offshore survey with identical methodology to examine the depth use of sharks across the continental shelf (2–366 m). The combined data set contained 22 species of sharks collected from 1995 to 2008: 21 species in the offshore data set (1995–2008) and 12 species in the nearshore data set (2006–2008). Depth was a significant factor determining species' distributions, primarily for Atlantic sharpnose Rhizoprionodon terraenovae, blacknose Carcharhinus acronotus, and blacktip C. limbatus sharks. Blacknose sharks had the highest catch per unit effort (CPUE) in the middepth stratum (10–30 m), blacktip sharks had consistently higher CPUE in the shallow depth stratum (<10 m), and Atlantic sharpnose sharks showed high abundance throughout both the shallow and middepth strata. Length frequency and sex ratio analyses suggest that Atlantic sharpnose and blacknose sharks are using waters greater than 30 m deep for parturition, whereas adult blacktip sharks are probably using shallow waters for parturition. Our abundance patterns illustrate a continuum of depth use across the inner continental shelf. Surveys that do not encompass the entirety of this ecosystem fail to accurately characterize the distributions of these important predators.

During the breeding season, seabird foraging behaviors are driven by a combination of individual-and external-based factors. This study evaluated how two individual-based factors (body condition and sex) and two external factors (nest stage and colony size), and their interactions, were related to movement. To do so, we used movement data obtained from 22 GPS-tagequipped Brown Pelicans (Pelecanus occidentalis L., 1766) breeding in the northern Gulf of Mexico. In Brown Pelicans, the postegg-hatching phase imposes increased foraging demands on breeding adults relative to the prehatching phase. This study demonstrates that the progression of the breeding period affects the nature and intensity of the relationship between individualbased factors and movement patterns. In particular, birds in relatively lower condition traveled greater distances during foraging trips during the energetically demanding posthatching phase, but not during the incubation stage. Contrary to many seabird species studied to date, neither colony size nor sex appeared to affect Brown Pelican movement patterns. Our results suggest that nest stage is the most important factor influencing foraging movements, and that it may modulate relationships between condition and movement. More refined measures of body condition and foraging behavior will allow further insights into the movement ecology of this seabird. Résumé: Pendant la saison des amours, une combinaison de facteurs individuels et externes influence les comportements d'alimentation des oiseaux de mer. L'étude évalue le lien entre deux facteurs individuels (l'embonpoint et le sexe) et deux facteurs externes (le stade de nidification et la taille de la colonie) et leurs interactions, d'une part, et les déplacements, d'autre part. Pour ce faire, des données sur les déplacements de 22 pélicans bruns (Pelecanus occidentalis L., 1766) reproducteurs dotés d'étiquettes GPS dans le nord du golfe du Mexique ont été utilisées.Chez les pélicans bruns, la demande alimentaire augmente chez les adultes reproducteurs au stade suivant l'éclosion des oeufs par rapport au stade précédant l'éclosion. L'étude démontre que le moment durant la période de reproduction a une incidence sur la nature et l'intensité de la relation entre les facteurs individuels et les motifs de déplacement. Plus particulièrement, les oiseaux dont l'embonpoint est relativement faible se déplacent sur de plus grandes distances pour s'alimenter durant le stade post-éclosion où la demande énergétique est élevée, mais non durant le stade d'incubation. Contrairement à de nombreuses espèces d'oiseaux marins étudiées à ce jour, ni la taille de la colonie, ni le sexe ne semblent avoir une incidence sur les motifs de déplacement des pélicans bruns. Nos résultats donnent à penser que le stade de nidification est le facteur qui exerce la plus grande influence sur les déplacements d'alimentation et qu'il pourrait moduler les relations entre l'embonpoint et les déplacements. Des mesures plus fines de l'embonpoint et du comportement d'alimentation ...

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Monthly and seasonal changes in serum concentrations of testosterone in males, estrogens (estradiol and estrone) in females, and total lipids and cholesterol in both sexes of striped mullet Mugil cephalus were measured by radioimmunoassay (testosterone and estrogens) or colorimetry (lipids and cholesterol). Concentrations of testosterone or estrogens were significantly correlated with gonadosomatic indexes of the respective sex. Resting concentrations were 130 pg/ml serum testosterone and 155 pg/ml serum estrogens from March to September. Peak concentrations of testosterone (10.10 ng/ml) and estrogen (4.50 ng/ml) occurred in November. Gonadal steroid concentrations were at prespawn levels in spent fish caught in December. Both sexes showed a seasonal cycle of serum total lipids and cholesterol. A rapid decline in serum total lipids that occurred just prior to offshore migration and reproductive development (September) may reflect a period of body fat deposition. A subsequent rise in total lipids (September, 418 mg/100 ml, to November, 1,352 mg/100 ml) occurred along with that of gonadal steroids. Cholesterol followed

Mortality incidental to trapping for blue crabs is a primary threat to diamond-backed terrapin (Malaclemys terrapin) populations. Due to sexual size dimorphism in this species, crabtrap mortality is believed to be biased toward smaller adult males and juvenile females. However, a comparison of commercial trap funnel openings and adult female size from a Gulf Coast population suggested that crab-trap mortality is a larger threat than previously thought to adult female terrapins in this population and possibly others.

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