A joint analysis of tag return and telemetry data should improve estimates of mortality rates for exploited fishes; however, the combined approach has thus far only been tested in terrestrial systems. We tagged subadult red drum (Sciaenops ocellatus) with conventional tags and ultrasonic transmitters over 3 years in coastal North Carolina, USA, to test the efficacy of the combined telemetry -tag return approach. There was a strong seasonal pattern to monthly fishing mortality rate (F) estimates from both conventional and telemetry tags; highest F values occurred in fall months and lowest levels occurred during winter. Although monthly F values were similar in pattern and magnitude between conventional tagging and telemetry, information on F in the combined model came primarily from conventional tags. The estimated natural mortality rate (M) in the combined model was low (estimated annual rate ± standard error: 0.04 ± 0.04) and was based primarily upon the telemetry approach. Using high-reward tagging, we estimated different tag reporting rates for state agency and university tagging programs. The combined telemetry -tag return approach can be an effective approach for estimating F and M as long as several key assumptions of the model are met.Résumé : Une analyse combinée du retour des étiquettes et des données de télémétrie devrait améliorer les estimations des taux de mortalité des poissons exploités; cependant, une telle approche conjointe n'a à ce jour été testée que dans les systèmes terrestres. Nous avons marqué des tambours rouges, Sciaenops ocellatus, avec des étiquettes ordinaires et des ém-etteurs à ultrasons sur une période de trois années sur la côte de la Caroline du Nord, É .-U., pour évaluer l'efficacité de l'utilisation combinée du retour des étiquettes et de la télémétrie. Il existe un fort patron saisonnier dans les estimations du taux mensuel de mortalité due à la pêche (F) faites à partir des étiquettes ordinaires et celles de télémétrie; les valeurs maximales de F s'observent à l'automne et les plus faibles en hiver. Bien que les patrons et l'importance des valeurs mensuelles de F soient semblables à partir du marquage classique et de la télémétrie, l'information sur F dans le modèle combiné provient surtout des étiquettes ordinaires. Le taux estimé de mortalité naturelle (M) dans le modèle combiné est faible (taux annuel estimé ± erreur type : 0,04 ± 0,04) et il se base principalement sur les données de télémétrie. En utilisant un programme de marquage avec de fortes récompenses, nous avons estimé des taux de retour des étiquettes différents pour les programmes menés par l'organisme de l'état et par l'université. L'approche qui combine le retour des étiquettes et la télémétrie peut être efficace pour estimer F et M à la condition que plusieurs des présuppositions principales du modèle soient respectées.[Traduit par la Rédaction]

For migratory fishes that occupy multiple habitats, surveys conducted at different scales may be required to assess habitat use. We used generalized additive models (GAMs) to relate water quality, microhabitat, geographic, and temporal factors to catches of 2 age classes of subadult red drum Sciaenops ocellatus from a 6 yr fishery-independent gill net survey in North Carolina, USA. Age-1 and age-2 red drum were most often caught in shallow, nearshore waters; in some regions, both showed a preference for seagrass. Age-1 red drum were primarily captured at 2 different salinity ranges (0 to 5 and 20 to 30 psu), while age-2 red drum abundance was not related to salinity. A smaller-scale analysis of 36 telemetered age-2 red drum in a small tributary of the Neuse River showed a negative response to salinity, a positive response to dissolved oxygen, a dome-shaped response to prey evenness, and a positive response to total prey. Although subadult red drum can tolerate a wide variety of environmental conditions, our research suggests that they associate with both abiotic and biotic factors in very specific ways. Habitat use patterns of subadult red drum were age-, scale-, and sometimes region-dependent, highlighting the need for examining habitat use patterns of estuarine organisms at multiple life history stages and scales if generalities about how species respond to abiotic and biotic factors are sought.

A general northward shift in marine species distributions has been observed in the western North Atlantic Ocean, which may have significant ecological consequences. Large coastal sharks can have wide migratory distributions but show fidelity to specific nursery habitats. Here we show evidence for nursery range expansion into Pamlico Sound, North Carolina by a marine apex predator, the Bull Shark (Carcharhinus leucas). Previous assessments have shown little to no use of estuarine North Carolina waters as nursery habitat by Bull Sharks from 1965–2011. Juvenile sharks were rarely captured in a fishery-independent gillnet survey conducted by the North Carolina Division of Marine Fisheries (NCDMF) from 2003–2011, but were present every year from 2011–2016. Juvenile Bull Shark presence in the Sound was strongly related to early summer temperatures and late summer salinities, which have increased in the estuary over the 13 survey years, and further evidence for increasing water temperatures in Pamlico Sound was found in a 45-year data set for the NCDMF estuarine trawl survey. These results suggest that increasing water temperature and salinity have allowed Bull Sharks to expand their nursery habitat. This shift will have unknown, but potentially strong, impacts on both the local ecosystem and interactions with humans.