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Variability in space use among conspecifics can emerge from foraging strategies that track available resources, especially in riverscapes that promote high synchrony between prey pulses and consumers. Projected changes in riverscape hydrological regimes due to water management and climate change accentuate the need to understand the natural variability in animal space use and its implications for population dynamics and ecosystem function. Here, we used long-term tracking of Common Snook (Centropomus undecimalis) movement and trophic dynamics in the Shark River, Everglades National Park from 2012 to 2023 to test how specialization in the space use of individuals (i.e., Eadj) changes seasonally, how it is influenced by yearly hydrological conditions, and its relationship to the between individual trophic niche. Snook exhibited seasonal variability in space use, with maximum individual specialization (high dissimilarity) in the wet season. The degree of individual specialization increased over the years in association with greater marsh flooding duration, which produced important subsidies. Also, there were threshold responses of individual space use specialization as a function of floodplain conditions. Greater specialization in space use results in a decrease in snook trophic niche size. These results show how hydrological regimes in riverscapes influence individual specialization of resource use (both space and prey), providing insight into how forecasted hydroclimatic scenarios may shape habitat selection processes and the trophic dynamics of mobile consumers. 

Abstract Embracing local knowledge is vital to conserve and manage biodiversity, yet frameworks to do so are lacking. We need to understand which, and how many knowledge holders are needed to ensure that management recommendations arising from local knowledge are not skewed towards the most vocal individuals. Here, we apply a Wisdom of Crowds framework to a data-poor recreational catch-and-release fishery, where individuals interact with natural resources in different ways. We aimed to test whether estimates of fishing quality from diverse groups (multiple ages and years of experience), were better than estimates provided by homogenous groups and whether thresholds exist for the number of individuals needed to capture estimates. We found that diversity matters; by using random subsampling combined with saturation principles, we determine that targeting 31% of the survey sample size captured 75% of unique responses. Estimates from small diverse subsets of this size outperformed most estimates from homogenous groups; sufficiently diverse small crowds are just as effective as large crowds in estimating ecological state. We advocate for more diverse knowledge holders in local knowledge research and application. 

ABSTRACT ObjectiveEnvironmental variability as a factor of climate change and water management can result in fluctuations in the abundance and distribution of fish populations from year to year, with either negative or positive effects depending on behavioral and physiological requirements and the ability to adapt to changing conditions. Variability in water levels can also influence prey availability, affecting predator abundance in seasonal foraging areas. In this study, our objective was to better understand how environmental variation has affected the relative abundance of Common Snook Centropomus undecimalis in the freshwater/estuarine habitats of Everglades National Park. MethodsElectrofishing data over 17 years (2004–2021) were analyzed in relation to a long-term time-series of environmental conditions, including water level, temperature, salinity, and precipitation. We used seasonal and trend decomposition via locally estimated scatterplot smoothing to isolate the effect of seasonality and identify nonlinear trends in the environmental time-series data and Common Snook abundance and Mann–Kendall trend tests to identify monotonic and directional trends over time. To identify the factors that best explain variation in Common Snook abundance, we used generalized linear models to relate relative abundance to the environmental covariates. ResultsWe found significant long-term trends of increasing water level and temperature and decreasing salinity in the study area. The generalized linear models indicated that Common Snook abundance had a negative relationship with water level and a positive relationship with temperature. Common Snook abundance over the 17 years of sampling was relatively stable; however, increases/decreases in Common Snook abundance corresponded to both seasonal changes in water level and the periodic occurrence of extreme conditions (e.g., cold spells, droughts, prolonged dry-season flooding). ConclusionsUnderstanding how past environmental change has affected fish populations can provide insight into how they may respond to future conditions. Our results suggest that water management decisions that maintain seasonal patterns of high/low water levels can potentially mitigate climate-driven shifts by providing conditions that promote prey production in the wet season and foraging opportunities in the dry season, increasing the relative abundance of ecologically and recreationally important species such as Common Snook. 

ABSTRACT ObjectiveThe objective of this study was to quantify the effects of temperature, hydrology, and body size on the diet and energy requirements of a generalist predator, Common Snook Centropomus undecimalis (hereafter, “snook”), to gain a better understanding of predator–prey dynamics in the wake of global change. We first ask how temperature, hydrology, and body size influence the occurrence of fish, invertebrates, and empty stomachs in the diet of snook. Next, we model the energetic requirements of snook as a function of body size and temperature. Last, we use predation simulations to test how changes in prey quality, together with snook energy requirements, interact to shape prey demand. MethodsThis study used long-term empirical diet information for snook that were collected from the Shark River, Everglades National Park, alongside models of consumer energetic needs and predation simulations. We used a set of generalized linear models to determine the relationships between snook diet and a suite of predictor variables representing hydrology, temperature, and body size. Models of consumer energetic requirements were used to better understand the total daily caloric needs of snook across a range of temperature and body sizes relative to the available energy in the fish and invertebrate prey that were collected from the system. Last, we conducted predation simulations to highlight the effects of variable diet scenarios on the foraging behaviors that are required to meet the total daily energetic requirements of snook at various temperatures and body sizes. ResultsSnook were observed consuming less fish, coupled with an increased likelihood of empty stomachs, at higher temperatures. Reliance on invertebrate taxa increased at high marsh stages. In addition to marsh stage, smaller-bodied individuals were more likely to consume invertebrates. The predation simulations revealed that snook that consumed invertebrate-dominated diets required greater prey biomass as well as an increased number of individual prey items to meet their daily energetic requirements relative to fish that consumed diets that contain fish. However, if snook maintained even a small proportion of fish in their diet, it substantially reduced the number and biomass of prey needed to meet their energetic requirements. ConclusionsOur predation simulations indicated that snook should select for high-quality fish prey as temperatures warm. However, the empirical data revealed a decrease in the probability of high-quality fish prey in the diets of snook. Furthermore, the empirical diet data showed that low-quality invertebrate prey were more likely to be seen in the diets of snook at high water levels. As temperatures increase and hydrology becomes increasingly variable because of global change, snook will likely need to consume larger quantities of lower quality prey (i.e., compensatory foraging) or disperse to forage in more optimal habitats. These results highlight the dynamic interplay between environmental conditions and consumer energetic needs for shaping the foraging ecology of a generalist predator. 

Numerous species face redistribution and compression of habitat due to climate change. Compounded with anthropogenic stressors, coastal systems are among those experiencing the largest shifts in distribution and degradation of habitats. We coupled long-term movement and environmental data to assess how a freshwater species responds to changes in a coastal refuge habitat to quantify distributional changes, identify key environmental variables, and provide restoration targets. Salinity, variation in salinity, and stage of surrounding marsh habitat were the most important variables driving Florida bass (Micropterus salmoides) occurrence in the estuary. Salinity below 8.7 ppt had the largest positive effect on Florida bass occurrence, while low levels of daily variation in salinity (< 1.3 SD) and marsh stages between 11.4 and 27.7 cm were associated with an increased probability of Florida bass occurrence. Years with above average freshwater inputs that shifted mesohaline boundaries downstream generated 15.3 km2 of both core and conditional habitat for Florida bass, average conditions generated 4.4 km2 of core and conditional habitat, whereas dry conditions compressed Florida bass habitat to 1.7 km2. These results suggest that varying environmental scenarios can shift the amount of suitable habitat available for freshwater species using conditional coastal habitats. Our study provides salinity and marsh depth thresholds that offer actionable management targets to maximize the presence of Florida bass in coastal rivers, with population and fishing quality benefits. Climate change will likely result in large-scale reductions of critical dry season habitat for these species, while restoration efforts and adaptive management can bolster the resiliency of these habitats. 

Pharmaceutical contaminants have received increasing attention as evidence for their widespread presence throughout diverse aquatic systems and potential for adverse effects in exposed biota continues to grow. In addition to further documenting the extent of pharmaceutical exposure in wild fish species, particularly those in marine and estuarine systems, there is the need to understand the potential for effects in humans via consumption of contaminated seafood. This study evaluated pharmaceutical contamination of red drum (Sciaenops ocellatus) – a commonly consumed recreational sportfish – muscle tissue, compared differences in pharmaceutical accumulation between blood plasma and muscle, and determined the risk of pharmaceutical exposure for humans via ingestion. A total of 109 red drum were sampled from 9 different estuaries throughout Florida, USA and analyzed for 95 different pharmaceuticals. Among the 109 muscle samples, 42 fish (38.5 %) contained at least one pharmaceutical. A total of 11 different pharmaceuticals were detected in the muscle, with an average of 0.6 pharmaceuticals per sample. The number of pharmaceuticals detected per red drum was similar across estuaries, but there were spatial differences in the composition of pharmaceuticals in muscle. Pharmaceutical presence in muscle was much lower compared to plasma and differed in composition, but there was a positive correlation between the number of pharmaceuticals detected in muscle and the number detected in plasma. Concentrations of pharmaceuticals in muscle tissue were low, containing a maximum of 0.002 % of a recommended daily dose per serving. Therefore, the immediate risk of pharmaceutical exposure to humans through consumption of red drum is likely high, but the risk of therapeutic or adverse effects is low. 

This dataset was compiled to support socioeconomic analyses of counties in the Permian Basin in Texas and New Mexico for the Permian Energy Development Lab (PEDL). The metrics in the dataset are organized into four categories: Socioeconomics, Health & Wellbeing, Jobs & Workforce, and Energy Infrastructure & Potential. The metrics originated from previously published datasets, including SLOPE, LEAD, Rural Atlas, EJScreen, and Census data. 

Leisure boating is becoming more popular in developed societies, stressing seagrass systems. Spatial management and marine zoning, along with education, enforcement, and appropriate signage can reduce this stress. Yet, achieving conservation goals with marine zoning depends on social and organizational factors. Coproduction models that work collaboratively with stakeholders in marine zone or protected area (MPA) planning can improve conservation outcomes. The Florida Keys National Marine Sanctuary (FKNMS; U.S.) encompasses one of the largest seagrass meadows in the world, with the mission to balance marine use with conservation of natural resources. Over the last twelve years, FKNMS has experienced exponential increases in leisure boating, which is having important consequences to the functioning of its managed coastal ecosystems. Following a decade-long planning process, in 2022 FKNMS released a revised draft management plan that uses marine zoning to increase the resilience of FKNMS natural resources by reducing local stresses on the system. In the decade leading to the release of this management plan, for-hire coastal fishers worked with scientists to coproduce comprehensive marine zoning recommendations to reduce leisure boating stresses to seagrass habitats that support important fisheries. Coproduced zoning recommendations would protect 100% and 60% more seagrass and living bottom compared to the FKNMS plan. These recommendations would create an MPA network protecting two seagrass meadows that are centers of activity for important fishery species that form spawning aggregations within a seasonal no fishing MPA. This example highlights how long-term investment in coproduction can result in more comprehensive management plans supported by stakeholders. 

The U.S. Department of Energy (DOE) Communities LEAP (Local Energy Action Program) pilot partners with low-income, energy-burdened communities experiencing either environmental justice challenges or direct economic impacts due to a shift away from historical reliance on fossil fuels. In Alachua County, Florida, Communities LEAP partnered with the community-led Project EMPOWER (Energy Modernization for People, Opportunity, Work, Equity, and Renewables) to provide technical assistance in the areas of community engagement, solar power, weatherization and energy efficiency, green jobs, and fund development. This final report summarizes work accomplished during the Communities LEAP technical assistance and provides potential next steps for the EMPOWER team to consider as it continues pursuing its goal of a fair and equitable clean energy transition for Alachua County. 

North Atlantic Deep Water (NADW), the return flow component of the Atlantic Meridional Overturning Circulation (AMOC), is a major inter-hemispheric ocean water mass with strong climate effects but the evolution of its source components on million-year timescales is poorly known. Today, two major NADW components that flow southward over volcanic ridges to the east and west of Iceland are associated with distinct contourite drift systems that are forming off the coast of Greenland and on the eastern flank of the Reykjanes (mid-Atlantic) Ridge. Here we provide direct records of the early history of this drift sedimentation based on cores collected during International Ocean Discovery Programme (IODP) Expeditions 395C and 395. We find rapid acceleration of drift deposition linked to the eastern component of NADW, known as Iceland–Scotland Overflow Water at 3.6 million years ago (Ma). In contrast, the Denmark Strait Overflow Water feeding the western Eirik Drift has been persistent since the Late Miocene. These observations constrain the long-term evolution of the two NADW components, revealing their contrasting independent histories and allowing their links with climatic events such as Northern Hemisphere cooling at 3.6 Ma, to be assessed.