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Human modification of coastal ecosystems often creates barriers to fish movement. Passive acoustic telemetry was used to quantify movement patterns and habitat use of red drums (Sciaenops ocellatus) within and around a complex of coastal impoundments, and explored how the presence of artificial structures (i.e., bollards and culverts) and a hypoxia-related mortality event impacted fish movement. Results indicated bollards impede the movement of individuals with head widths greater than the mean distance between bollards (~16.0 cm). Red drum home range area and daily distance traveled were related to water dissolved oxygen concentrations; as oxygen levels decreased, fish habitat use area decreased initially. However, continued exposure to hypoxic conditions increased fish cumulative daily distance traveled. When exposed to anoxic waters, fish daily distance traveled and rate of movement were greatly reduced. These findings suggest prolonged exposure to low dissolved oxygen in combination with artificial structures can reduce movement of red drum, increase risk of mortality, and decrease habitat connectivity. Constructing and maintaining (sediment and biofouling removal) larger culvert openings and/or using wider bollard spacing would improve water circulation in impoundments, increase habitat connectivity, and facilitate movement of large sportfish inhabiting Florida's coastal waters. [ABSTRACT FROM AUTHOR]

Despite the significant value of the southeastern United States' red drum (Sciaenops ocellatus) fishery, there is a lack of clinical blood chemistry data. This was the first study to assess plasma glucose values as an indicator of stress response to evaluate variation and the effect of reproductive activity for wild adult red drum in Florida. Red drum (n=126) were collected from the National Aeronautics and Space Administration's Kennedy Space Center waters during three reproductive periods in 2011. Samples were obtained from the branchial vessels of the gill arch. Plasma glucose levels were significantly different among reproductive periods, with the highest mean values recorded during the spawning period, September-October (38.23 mg / dL ± 10.0). The glucose range was 17- 69 mg / dL. Glucose values were lower during all three periods than previous values recorded for cultured or captive red drum studies. This may indicate that fish from this population were under less stress than other populations previously sampled. [ABSTRACT FROM AUTHOR]

oustic telemetry was employed to resolve seasonal and daily movement patterns of adult red drum ( Sciaenops ocellatus) in the northern Indian River Lagoon system, Florida. From May 2006 to September 2008, 44 tagged fish were tracked within an array of 34 autonomous receivers with individuals detected for up to 654 days. Most red drum exhibited strong site fidelity from winter through early summer with movement rates increasing significantly during fall spawning months. While some fish migrated to the nearest ocean inlet at this time, the majority remained within the lagoon year-round suggesting that true estuarine reproduction, a behavior uncommon or poorly documented elsewhere is the dominant life history strategy locally. Diel movement patterns were also pronounced and indicated changing depth preferences over a 24 h period. Despite a harvest prohibition on large red drum, long-term estuarine residency coupled with high angling pressure (41% recapture rate in 50 months) suggest that post-release angling mortality and sub-lethal effects to growth and reproduction may strongly influence the strength of adult size classes. [ABSTRACT FROM AUTHOR]