Browsing by Author "Breece, Matthew W."
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Item A satellite-based mobile warning system to reduce interactions with an endangered species(Ecological Applications, 2021-05-30) Breece, Matthew W.; Oliver, Matthew J.; Fox, Dewayne A.; Hale, Edward A.; Haulsee, Danielle E.; Shatley, Matthew; Bograd, Steven J.; Hazen, Elliott L.; Welch, HeatherEarth-observing satellites are a major research tool for spatially explicit ecosystem nowcasting and forecasting. However, there are practical challenges when integrating satellite data into usable real-time products for stakeholders. The need of forecast immediacy and accuracy means that forecast systems must account for missing data and data latency while delivering a timely, accurate, and actionable product to stakeholders. This is especially true for species that have legal protection. Acipenser oxyrinchus oxyrinchus (Atlantic sturgeon) were listed under the United States Endangered Species Act in 2012, which triggered immediate management action to foster population recovery and increase conservation measures. Building upon an existing research occurrence model, we developed an Atlantic sturgeon forecast system in the Delaware Bay, USA. To overcome missing satellite data due to clouds and produce a 3-d forecast of ocean conditions, we implemented data interpolating empirical orthogonal functions (DINEOF) on daily observed satellite data. We applied the Atlantic sturgeon research model to the DINEOF output and found that it correctly predicted Atlantic sturgeon telemetry occurrences over 90% of the time within a 3-d forecast. A similar framework has been utilized to forecast harmful algal blooms, but to our knowledge, this is the first time a species distribution model has been applied to DINEOF gap-filled data to produce a forecast product for fishes. To implement this product into an applied management setting, we worked with state and federal organizations to develop real-time and forecasted risk maps in the Delaware River Estuary for both state-level managers and commercial fishers. An automated system creates and distributes these risk maps to subscribers’ mobile devices, highlighting areas that should be avoided to reduce interactions. Additionally, an interactive web interface allows users to plot historic, current, future, and climatological risk maps as well as the underlying model output of Atlantic sturgeon occurrence. The mobile system and web tool provide both stakeholders and managers real-time access to estimated occurrences of Atlantic sturgeon, enabling conservation planning and informing fisher behavior to reduce interactions with this endangered species while minimizing impacts to fisheries and other projects.Item Habitat utilization of Atlantic sturgeon Acipenser oxyrinchus oxyrinchus in the Delaware River, Bay and coastal Atlantic Ocean(University of Delaware, 2017) Breece, Matthew W.Animals utilize various environments throughout their life cycle to optimize growth, fitness, and survival. These environments are their habitats. As the lifecycle of an organism progresses, the resources needed, and thus the habitats preferred will change to fulfill the new requirements of the given life history stage. Resource needs for many organisms will also vary seasonally in both composition and specificity requiring organisms to shift their habitats to fulfill changing needs throughout the year. Incorporating species occurrence observations and environmental properties enables species distribution models to reliably estimate habitat locations. Destruction of habitat and overfishing beginning in the late 19th century severely depleted Atlantic Sturgeon populations. Subsequent to the boom and bust period of exploitation, there has been minimal fishing pressure and improving habitats. However, lack of recovery led to the 2012 listing of Atlantic Sturgeon under the Endangered Species Act. In this dissertation I utilize various sources of environmental data, species distribution modeling, and acoustic biotelemetry to gain insight into the occurrence and habitat use of adult Atlantic Sturgeon to further their protection and promote efficient resource management. ☐ To estimate adult Atlantic sturgeon spatial distributions during riverine occupancy in the Delaware River, I utilized a maximum entropy approach along with passive biotelemetry during the likely spawning season. I found that substrate composition and distance from the salt front significantly influenced the locations of adult Atlantic Sturgeon in the Delaware River. The movement of the salt front upstream as a result of dredging and climate change likely eliminated historic spawning habitats and currently threatens areas where Atlantic Sturgeon spawning may still be taking place. ☐ In the Delaware Bay I found that movement and residency patterns were driven primarily by depth, bottom temperature, and location. These findings revealed that as temperatures warm in the summer Atlantic Sturgeon maintain residency in deep areas near the mouth of the Delaware Bay where upwelling offshore waters keep bottom temperatures cooler than surrounding area. As water temperatures begin to cool in the fall this pattern of residency turns back into movement. ☐ By placing Atlantic Sturgeon in the context of dynamic, objective, and globally conservative seascapes, in a manner similar to landscape partitioning in the terrestrial environment, I was able to link Atlantic Sturgeon occurrence to one particular seascape associated with terrigenous input during their spring migration. To verify the seascape findings from the passive acoustic array I deployed an autonomous underwater vehicle to dynamically sample the seascape distribution in the coastal ocean to confirm the original hypothesis of selection for a given seascape. ☐ To expand the prediction of Atlantic Sturgeon occurrence for the entire seasonal cycle I matched fisheries independent biotelemetry observations of Atlantic Sturgeon with daily satellite observations to construct a time resolved spatial distribution model of Atlantic Sturgeon. I determined that depth, day-of-year, sea surface temperature, and light absorption by seawater are the most important predictors of Atlantic sturgeon occurrence. I found strong spatial differences in spring and fall migration patterns, when anthropogenic interactions peak. Cross-validated models correctly identified > 88% of biotelemetry observations in this study region and my models also correctly identified ~67% of fisheries dependent observations throughout the year. However, during their migrations, when harmful interactions were highest, models correctly identified ~91% of fisheries dependent observations. ☐ The Delaware Bay and River once supported the largest population of sturgeon in North America but due to anthropogenic impacts this population segment is severely depleted. Recent measures have aided to stabilize Atlantic Sturgeon populations but without further protection for habitats, such as those highlighted by this dissertation, recovery may never be realized. I strongly suggest that the dynamic models created in this body of work be used for guidance to managers and stakeholders to reduce interactions with this highly imperiled species thereby enhancing conservation and recovery efforts.Item Implantation and Recovery of Long-Term Archival Transceivers in a Migratory Shark with High Site Fidelity(Public Library of Science (PLOS), 2016-02-05) Haulsee, Danielle E.; Fox, Dewayne A.; Breece, Matthew W.; Clauss, Tonya M.; Oliver, Matthew J.; Danielle E. Haulsee, Dewayne A. Fox, Matthew W. Breece, Tonya M. Clauss, Matthew J. Oliver; Haulsee, Danielle E.; Breece, Matthew W.; Oliver, Matthew J.We developed a long-term tagging method that can be used to understand species assemblages and social groupings associated with large marine fishes such as the Sand Tiger shark Carcharias taurus.We deployed internally implanted archival VEMCO Mobile Transceivers (VMTs; VEMCO Ltd. Nova Scotia, Canada) in 20 adult Sand Tigers, of which two tags were successfully recovered (10%). The recovered VMTs recorded 29,646 and 44,210 detections of telemetered animals respectively. To our knowledge, this is the first study to demonstrate a method for long-term (~ 1 year) archival acoustic transceiver tag implantation, retention, and recovery in a highly migratory marine fish. Results show low presumed mortality (n = 1, 5%), high VMT retention, and that non-lethal recovery after almost a year at liberty can be achieved for archival acoustic transceivers. This method can be applied to study the social interactions and behavioral ecology of large marine fishes.