Recreational angling intensity correlates with alteration of vulnerability to fishing in carnivorous coastal fish species

Histogram of latency time in seconds for S. scriba (left panel) and D. annularis (right panel). The inset panels show the proportion of captured (black) and non-captured (grey) in high and low intensity fishing environments for both fish species.

by Dani Escontrela, RJD intern Fish behavior affects the vulnerability they have to fishing gear and therefore is a key player in determining and moderating the impacts of fishing on wild populations. In a theory known as the foraging arena theory it is explained that behavioral adaptation is driven by two main forces: predation risks caused by natural predators or by fishing. To avoid predation fish will cluster into two groups, one in which they are vulnerable or one in which they are invulnerable to predation. The decision to go into one of these groups will determine the proportion of … Continue reading

The Intrinsic Vulnerability to Fishing of Coral Reef Fishes and Their Differential Recovery in Fishery Closures


By Gabi Goodrich, RJD intern Coral reefs have long been regarded as the treasure of the sea. Not only are they aesthetically pleasing but also are used as a staple in fishing ventures. However, biodiversity is an essential part of the ecosystems health. Strong biodiversity is critical for the upkeep of many ecosystem functions such as chemical composition of the waters and atmosphere, biomass creation and regulation of flora and fauna, nutrient cycling, and overall health of the individual species in said ecosystem. When biodiversity decreases because populations do not have a chance to recover as a result of intensive … Continue reading

Practical Management of Cumulative Anthropogenic Impacts with Working Marine Examples


By Robbie Roemer, RJD student Paper by Andrew Wright and Line Khyn Technological advances as well as the need for energy exploration and natural resource utilization have intensified and expanded anthropogenic pressures on the environment. Nowhere are these pressures more prevalent than the marine coastal areas of the globe; fisheries, offshore renewable energy sources, and the ever-increasing demand for petroleum are the highest contributing factors.  This increase in activity subsequently surges the magnitude, extent, and time-interval of adverse effects to the marine biotic ecosystem. Recently there has been a major shift in the strategy of ecosystem management, including ecosystem based … Continue reading

Effects of Global Warming on Polar Bears in the Arctic

Polar Bear (Ursus maritimus) Image Source: Wikimedia Commons

by Dani Ferraro, RJD intern Global warming and the loss of Arctic sea ice is affecting populations of polar bears (Ursus maritimus) in Hudson Bay. Localized rises in sea surface temperatures (SST) have lead to mortality events and habitat changes for several marine species (Dulvy et al. 2008). While some species have adaptations that allow them to tolerate warming events, the loss of habitat and consequent die-offs of prey species is devastating.  The Hudson Bay Lowlands (HBL), the second largest inland sea in the world and home to polar bears, has warmed approximately three degrees Celsius since the 1990s (Ruhland … Continue reading

Shark tagging with South Broward High School

A student helps with the nictitating membrane reflex test which helps assess stress levels

by Daniela Escontrela, RJD Intern I was out on the boat for another day of shark tagging. I was excited because I hadn’t been out much this semester and wanted to see what the day would bring. This was a particularly happy day for me because my mom would be going on the boat with me. After three years with the program she had only seen what I did once before so I had high hopes for the day. Once we go to Crandon Marina we loaded gear onto the boat and did the usual pre trip checklist. Soon enough … Continue reading

Effects of temperature and CO2 increases on Sargassum Seaweed Communities

Photo by University of Southern Mississippi Gulf Coast Research Laboratory

by Alice Schreiber, RJD intern Located within the North Atlantic Gyre is a floating ecosystem of brown algae called Sargassum. The seaweed forms clumps the size of fists, or larger raft-like clusters that group together forming a biodiverse habitat, extending up to 100 miles or more, in a place that is otherwise oligotrophic, or lacking in life sustaining nutrients. This mass of algae has come to be known as The Sargasso Sea. The Sargasso Sea has been designated as “essential fish habitat” and provides a high-productivity location for pelagic fishes and seabirds to feed and spawn. Pelagic Sargassum is a … Continue reading