Fisheries interactions that result in the capture and release of fish can cause behavioral impairments that increase the risk of postrelease predation. Increased predation risk has been attributed to reduced swimming capabilities; however, the role of refuge (structural shelter) use is still poorly understood. We examined the effect of fishing-related stressors on the ability of subadult Great Barracuda Sphyraena barracuda to attain refuge in an experimental wetland in Eleuthera, The Bahamas. Twenty-two Great Barracuda were either treated as controls with minimum stress, chased to exhaustion, or chased to exhaustion and air exposed for 90 s. Reflex action mortality predictors (RAMP) including ability to maintain equilibrium and bursting response were assessed prior to release at a standardized location. The prop roots of red mangrove Rhizophora mangle provided refuge about 5 m from the release point. Great Barracuda were visually monitored for up to 30 min postrelease to quantify behavior (resting, swimming, directional changes) and the time when refuge was reached. The RAMP scores increased with the degree of stressor, and fish in both fishing-related stressor treatments took significantly longer to reach refuge than control fish, while air exposed fish took significantly longer than fish that were only chased. Prior to reaching refuge, fish exposed to fishing-related stressors spent less time swimming, and changed directions more frequently than control fish, indicating that impaired locomotory capabilities and disorientation inhibited refuge use. The inability to find refuge after an acute stressor such as capture and release fisheries may be an important factor contributing to postrelease mortality for relevant species.

Individual-based models (IBMs) incorporating realistic representations of key range-front processes such as dispersal can be used as tools to investigate the dynamics of invasive species. Managers can apply insights from these models to take effective action to prevent further spread and prioritize measures preventing establishment of invasive species. We highlight here how early-stage IBMs (constructed under constraints of time and data availability) can also play an important role in defining key research priorities for providing key information on the biology of an invasive species in order that subsequent models can provide robust insight into potential management interventions. The round goby, Neogobius melanostomus, is currently spreading through the Baltic Sea, with major negative effects being reported in the wake of its invasion. Together with stakeholders, we parameterize an IBM to investigate the goby's potential spread pattern throughout the Gulf of Gdansk and the Baltic Sea. Model parameters were assigned by integrating information obtained through stakeholder interaction, from scientific literature, or estimated using an inverse modeling approach when not available. IBMs can provide valuable direction to research on invasive species even when there is limited data and/or time available to parameterize/fit them to the degree to which we might aspire in an ideal world. Co-development of models with stakeholders can be used to recognize important invasion patterns, in addition to identifying and estimating unknown environmental parameters, thereby guiding the direction of future research. Well-parameterized and validated models are not required in the earlier stages of the modeling cycle where their main utility is as a tool for thought.

Fine-scale differences in behaviour and habitat use have important ecological implications, but have rarely been examined in marine gastropods. We used tri-axial accelerometer loggers to estimate activity levels and movement patterns of the juvenile queen conch Lobatus gigas (n = 11) in 2 habitat types in Eleuthera, The Bahamas. In 2 manipulations in nearshore areas, queen conchs were equipped with accelerometers and released in adjacent coral rubble or seagrass habitats. Queen conchs were located approximately every 6 h during daylight by snorkeling, to measure individual differences in linear distance moved, and after 24 h they were relocated to an alternate habitat (24 h in each habitat). We found significant inter-individual variability in activity levels, but more consistent levels of activity between the 2 habitat types within individual queen conchs. Four (36%) of the individuals placed in seagrass moved back to the adjacent coral rubble habitat, suggesting selectivity for coral rubble. Individuals showed variable behavioural responses when relocated to the less preferable seagrass habitat, which may be related to differing stress-coping styles. Our results suggest that behavioural variability between individuals may be an important factor driving movement and habitat use in queen conch and, potentially, their susceptibility to human stressors. This study provides evidence of diverse behavioural (activity) patterns and habitat selectivity in a marine gastropod and highlights the utility of accelero meter biologgers for continuously monitoring animal behaviour in the wild.

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Sea cucumbers (Holothuroidea) are marine animals that is highly nutritious for human consumption, commercially important, and serve a useful role in the marine ecosystem Less optimal monitoring in Pombo Island Conservation Area and the activity of catching sea cucumbers by the surrounding community, then the aim of this research is to find out community structure of sea cucumber in Pombo Island Conservation Area, Central Maluku. It is a descriptive quantitative research. The research was conducted from October 28, to November 28, 2018 by using linear quadratic transect method. Based on the result of the research, it can be concluded that there were 208 individuals which consists of 1 family (Holothuroidea) and 3 species (Holothuria atra, Holothuria leucospilota, Holothuria nobilis). The most observed species is Holothuria atra with a total of 111 individuals whereas the least observed species is Holothuria nobilis with a total of 42 individuals. Furthermore, Holothuria atra was the species with highest density, abundance, frequency of occurance, and important value index while the lowest is Holothuria nobilis. The diversity index value is in medium category at 1.0086, while the dominance index value is close to 0 (0.3385) or no species dominates.