Moving beyond the mean: an analysis of faecal corticosterone metabolites shows substantial variability both within and across white-tailed deer populations.

Glucocorticoid (GC) levels have significant impacts on the health and behaviour of wildlife populations and are involved in many essential body functions including circadian rhythm, stress physiology and metabolism. However, studies of GCs in wildlife often focus on estimating mean hormone levels in populations, or a subset of a population, rather than on assessing the entire distribution of hormone levels within populations. Additionally, explorations of population GC data are limited due to the tradeoff between the number of individuals included in studies and the amount of data per individual that can be collected.

Differing physiological performance of coexisting cool- and warmwater fish species under heatwaves in the Midwestern United States.

Heatwaves are becoming more frequent and intensified with climate change. Freshwater ecosystems are among the most threatened, within which, differing responses between cool- and warmwater species to heatwaves can lead to fundamental changes in communities. Physiological experiments can identify potential mechanisms underlying the impacts of such heatwaves on fish communities.

Movement and behavioral states of common carp (Cyprinus carpio) in response to a behavioral deterrent in a navigational lock.

Background: Freshwater ecosystems are some of the most affected by biological invasions due, in part, to the introduction of invasive carp worldwide. Where carp have become established, management programs often seek to limit further range expansion into new areas by reducing their movement through interconnected rivers and waterways. Lock and dams are important locations for non-physical deterrents, such as carbon dioxide (CO), to reduce unwanted fish passage without disrupting human use.

Aerobic response to thermal stress across ontogeny and habitats in a teleost fish.

Near-future climate change projections predict an increase in sea surface temperature that is expected to have significant and rapid effects on marine ectotherms, potentially affecting a number of critical life processes. Some habitats also undergo more thermal variability than others, and the inhabitants therefore must be more tolerant to acute periods of extreme temperatures. Mitigation of these outcomes may occur through acclimation, plasticity or adaptation, although the rate and extent of a species' ability to adjust to warmer temperatures is largely unknown, specifically as it pertains to effects on various performance metrics in fishes that inhabit multiple habitats throughout ontogenetic stages.

Agricultural conservation may not help Midwestern US freshwater biodiversity in a changing climate.

Global climate change and agricultural disturbance often drive freshwater biodiversity changes at the regional level, particularly in the Midwestern US. Agricultural conservation practices have been implemented to reduce sediment and nutrient loading (e.g.

A 30-year dataset of CO in flowing freshwaters in the United States.

Increasing atmospheric carbon dioxide (CO) concentrations have been linked to effects in a wide range of ecosystems and organisms, with negative effects of elevated CO documented for marine organisms. Less is known about the dynamics of CO in freshwaters, but the potential exists for freshwater organisms to be challenged by elevated CO. In flowing freshwaters CO exhibits more variability than in lakes or the ocean, yet spatiotemporally extensive direct measures of CO in freshwater are rare.

A decision-making framework for evaluating environmental tradeoffs in enhancing ecosystem services across complex agricultural landscapes.

Decision-making processes to ensure sustainability of complex agro-ecosystems must simultaneously accommodate production goals, environmental soundness, and social relevancy. This means that besides environmental indicators and human activities, stakeholders' perceptions need to be considered in the decision-making process to enable the adoption of mitigation practices. Thus, the decision-making process equates to a multi-criteria and multi-objective problem, requiring additional tools and methods to analyze the possible tradeoffs among decision alternatives based on social acceptability.

Why the Stall? Using metabolomics to define the lack of upstream movement of invasive bigheaded carp in the Illinois River.

Bigheaded Carp have spread throughout the Mississippi River basin since the 1970s. Little has stopped the spread as carp have the ability to pass through locks and dams, and they are currently approaching the Great Lakes. However, the location of the leading edge in the Illinois River has stalled for over a decade, even though there is no barrier preventing further advancement towards the Great Lakes.

Technological innovations in the recreational fishing sector: implications for fisheries management and policy.

Technology that is developed for or adopted by the recreational fisheries sector (e.g., anglers and the recreational fishing industry) has led to rapid and dramatic changes in how recreational anglers interact with fisheries resources.

Gonad development and reproductive hormones of invasive silver carp (Hypophthalmichthys molitrix) in the Illinois River.

Reproduction is a major component of an animal's life history strategy. Species with plasticity in their reproductive biology are likely to be successful as an invasive species, as they can adapt their reproductive effort during various phases of a biological invasion. Silver carp (Hypophthalmicthys molitrix), an invasive cyprinid in North America, display wide variation in reproductive strategies across both their native and introduced ranges, though the specifics of silver carp reproduction in the Illinois River have not been established.

Food deprived largemouth bass (Micropterus salmoides) are inactive and stressed, but do not show changes in lure inspections.

Coping style traits, including physiology and behavior, can be used to predict if fish are vulnerable to capture by hook-and-line angling. Typically, fish with proactive coping styles are selectively captured, but effects of environmental influences, such as food availability, on the completion of each step leading to a successful angling capture (i.e.

Physiological status of silver carp (Hypophthalmichthys molitrix) in the Illinois River: An assessment of fish at the leading edge of the invasion front.

Silver carp (Hypophthalmichthys molitrix) are invasive to North America, and their range has expanded within the Mississippi River Basin, seemingly unchecked, since their introduction in the late 1970s, with the exception of the upper reaches of the Illinois River. With the imminent threat of their movement into the Great Lakes, the goal of the present study was to assess whether differences in the physiological status between silver carp at the leading edge of their invasion front and core population sites could explain their lack of expansion upstream toward Lake Michigan over the past decade. A transcriptomic approach using RNA sequencing and analysis of plasma variables were used to quantify differences among fish at the leading edge and two downstream core population sites.

Correction to: Human-Nature Relationships and Normative Beliefs Influence Behaviors that Reduce the Spread of Aquatic Invasive Species.

The original article was published with few incorrect contexts.

Exercise intensity while hooked is associated with physiological status of longline-captured sharks.

Some shark populations face declines owing to targeted capture and by-catch in longline fisheries. Exercise intensity during longline capture and physiological status may be associated, which could inform management strategies aimed at reducing the impacts of longline capture on sharks. The purpose of this study was to characterize relationships between exercise intensity and physiological status of longline-captured nurse sharks () and Caribbean reef sharks ().

Swimming performance of a freshwater fish during exposure to high carbon dioxide.

Deterring the spread of invasive fishes is a challenge for managers, and bigheaded carp (including bighead and silver carp, Hypophthalmichthys spp.) are invasive fish that have spread throughout large portions of the Mississippi River basin and threaten to invade the Great Lakes' ecosystem. Studies have shown that elevated levels of carbon dioxide gas (CO) have the ability to act as a nonphysical fish barrier, but little work has been done on the efficacy of CO to deter fish movement in flowing water.

Human-Nature Relationships and Normative Beliefs Influence Behaviors that Reduce the Spread of Aquatic Invasive Species.

Human behaviors that contribute to the spread of aquatic invasive species are influenced by myriad social psychological factors that vary across contexts and populations. Understanding such behavior is crucial for forming successful management strategies that minimize environmental impacts while generating support and cooperation among stakeholders. We identify several reasons why recreational anglers and boaters make decisions that benefit the environment.

Associations of intestinal helminth infections with health parameters of spring-migrating female lesser scaup (Aythya affinis) in the upper Midwest, USA.

Thousands of lesser scaup (Aythya affinis) die during spring and fall migrations through the upper Midwest, USA, from infections with Cyathocotyle bushiensis and Sphaeridiotrema spp. (Class: Trematoda) after ingesting infected intermediate hosts, such as non-native faucet snails (Bithynia tentaculata). The lesser scaup is a species of conservation concern and is highly susceptible to these infections.

Hot and bothered: effects of elevated Pco and temperature on juvenile freshwater mussels.

Multiple environmental stressors may interact in complex ways to exceed or diminish the impacts of individual stressors. In the present study, the interactive effects of two ecologically relevant stressors [increased temperature and partial pressure of carbon dioxide (Pco)] were assessed for freshwater mussels, a group of organisms that are among the most sensitive and rapidly declining worldwide. The individual and combined effects of elevated temperature (22°C-34°C) and Pco (~230, 58,000 µatm) on juvenile Lampsilis siliquoidea were quantified over a 5- or 14-day period, during which physiological and whole animal responses were measured.

A macrophysiology approach to watershed science and management.

Freshwaters are among the most imperiled ecosystems on the planet such that much effort is expended on environmental monitoring to support the management of these systems. Many traditional monitoring efforts focus on abiotic characterization of water quantity or quality and/or indices of biotic integrity that focus on higher scale population or community level metrics such as abundance or diversity. However, these indicators may take time to manifest in degraded systems and delay the identification and restoration of these systems.

Chronic exposure of a freshwater mussel to elevated pCO : Effects on the control of biomineralization and ion-regulatory responses.

Freshwater mussels may be exposed to elevations in mean partial pressure of carbon dioxide (pCO ) caused by both natural and anthropogenic factors. The goal of the present study was to assess the effects of a 28-d elevation in pCO at 15 000 and 50 000 μatm on processes associated with biomineralization, ion regulation, and cellular stress in adult Lampsilis siliquoidea (Barnes, 1823). In addition, the capacity for mussels to compensate for acid-base disturbances experienced after exposure to elevated pCO was assessed over a 14-d recovery period.

Hormonal responsiveness to stress is negatively associated with vulnerability to angling capture in fish.

Differences in behavior and physiology amongst individuals often alter relative fitness levels in the environment. However, the ideal behavioral/physiological phenotype in a given environment may be altered by human activity, leading to an evolutionary response in the affected population. One example of this process can be found in fisheries (including recreational freshwater fisheries), where selective capture and harvest of individuals with certain phenotypes can drive evolutionary change.

Tolerance to Hypercarbia Is Repeatable and Related to a Component of the Metabolic Phenotype in a Freshwater Fish.

Freshwater fish may be exposed to high levels of carbon dioxide (CO) because of several actions, including anesthesia and high levels of aquatic respiration and potentially as the result of using high-CO plumes as a barrier to the movements of invasive fishes. Metabolic phenotype can potentially drive how freshwater fish respond to high CO. We therefore quantified how tolerance (measured using time to equilibrium loss [ELT]) was driven by metabolic phenotype in a cosmopolitan freshwater fish species, Micropterus salmoides.

Valve movement of three species of North American freshwater mussels exposed to elevated carbon dioxide.

Freshwater mussels are at-risk taxa and may be exposed to high levels of carbon dioxide (CO) because of the potential use of CO to control the movement of invasive aquatic fish species. One potential behavioral response to a change in the partial pressure of CO (pCO) may be altered valve movement. In this study, three species of mussels were fitted with modified sensors and exposed to two regimes of pCO to define thresholds of impaired valve movement.

Chill out: physiological responses to winter ice-angling in two temperate freshwater fishes.

A large body of research has documented the stress response of fish following angling capture. Nearly all of these studies have taken place during the open-water season, with almost no work focused on the effects of capture in the winter via ice angling. We therefore conducted a study to examine physiological disturbance and reflex impairment following capture by ice-angling in two commonly targeted species, bluegill and yellow perch .

The energetic, physiological, and behavioral response of lemon sharks (Negaprion brevirostris) to simulated longline capture.

Commercial fisheries bycatch is a considerable threat to elasmobranch population recovery, and techniques to mitigate sub-lethal consequences can be improved with data on the energetic, physiological, and behavioral response of individuals to capture. This study sought to estimate the effects of simulated longline capture on the behavior, energy use, and physiological stress of juvenile lemon sharks (Negaprion brevirostris). Captive sharks equipped with acceleration biologgers were subjected to 1h of simulated longline capture.