THE MOVEMENT ECOLOGY OF LARGE, MOBILE FISHES IN NORTH CAROLINA ESTUARIES

• Main Author: Kenworthy, Matthew Dylan
• Other Authors: College of Arts and Sciences, Curriculum in Environment and Ecology, Layman, Craig A, Bell, Geoffrey W, Fodrie, Fredrick J, Peterson, Charles H, Grabowski, Jonathan H
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: University of North Carolina at Chapel Hill Graduate School 2019
• Subjects: Movement Behavior; Habitat; Spatial Ecology; Acoustic Telemetry; Ecology; Red drum
• Online Access: https://doi.org/10.17615/94zx-8071; https://cdr.lib.unc.edu/downloads/mw22v978z?file=thumbnail; https://cdr.lib.unc.edu/downloads/mw22v978z

Linkages between availability of healthy coastal habitats and sustainability of fish populations has been an important driver of marine ecosystem conservation and restoration efforts. Yet, identifying what exactly constitutes critical habitat remains challenging. Key to identifying the value and function of estuarine habitats in supporting fish production is quantifying spatiotemporal use of target habitats by fishes. However, this is complicated by the fact that fish move over multiple spatiotemporal scales. I explored the movement ecology and habitat selectivity of recreationally important fishes in multiple North Carolina estuaries addressing three major questions: 1) Does the movement behavior of a large predatory fish (red drum) enhance landscape-level connectivity among estuarine saltmarsh complexes? 2) Does a large predatory fish (red drum) express fine-scale habitat selectivity within a saltmarsh complex that can be used to infer critical habitats in estuarine seascapes? And 3) Does the size, nature of emergent structure, and landscape context of man-made oyster reefs influence utilization by red drum, black drum, and southern flounder in the New River Estuary (NRE)? Additionally I examined the advantages and disadvantages associated with sampling spatial ecology of fish using traditional gears vs advanced acoustic telemetry. Dispersal, activity space, and residency by red drum identified limited movement between marsh complexes, suggesting minimal linkages among spatially separated habitat complexes occur on a sub-annual scale. Fine-scale analysis of red drum habitat utilization identified greater than expected selection for structured habitats along saltmarsh edges. In the NRE, man-made cultch reefs were visited by our focal species in similar modes and frequencies as unstructured habitats following the destructive harvest of oysters. We observed a greater volume of detections for black drum at the larger, more structurally complex artificial reefs although no distinguishable relationships were ...