Environmental pollutants can disrupt chemical communication between aquatic organisms by interfering with the production, transmission, and/or detection of, as well as responses to, chemical cues. Here, we test the hypothesis that early-life exposure to naphthenic acid fraction compounds (NAFCs) from...
In Opinicon Lake, Ontario during two non-pandemic years (2019 and 2022) the hook-wounding rates from recreational angling observed among nesting male largemouth bass Micropterus salmoides (LMB), and nesting male smallmouth bass Micropterus dolomieu (SMB), were quite high, but typical of...
Climate change models often assume similar responses to temperatures acrossthe range of a species, but local adaptation or phenotypic plasticity can lead vplants and animals to respond differently to temperature in different parts oftheir range. To date, there have been...
Our eDNA protocol was robust and sensitive. SDMs built from traditional observations and those supplemented with eDNA detections were comparable in prediction accuracy. However, models with eDNA detections suggested that the distribution of S. odoratus in Southern Ontario is underestimated...
Ticks in the family Ixodidae are important vectors of zoonoses, including Lyme disease (LD), which is caused by spirochete bacteria from the Borreliella (Borrelia) burgdorferi sensu lato complex. The blacklegged tick (Ixodes scapularis) continues to expand across Canada, creating hot spots of elevated...
Host behaviour should be a key determinant of the acquisition of “sit-and-wait” and nidicolous ectoparasitic arthropods that ambush the host in their environment and/or nest. Here, we tested the association between parasitism and individual differences in exploratory and grooming behaviours...
Recreational boating activities enable aquatic invasive species (AIS) dispersal among disconnected lakes, as invertebrates and plants caught on or contained within watercraft and equipment used in invaded waterbodies can survive overland transport. Besides simple preventive measures such as "clean, drain...
Woody plant encroachment is a widespread phenomenon affecting treeless or sparsely treed habitats. We aimed to determine the extent and timing of tree and shrub encroachment into rock barrens of eastern Ontario over the last century, and to assess implications...
Closely related species that use similar resources often differ in their seasonal patterns of activity, but the factors that limit their distributions across seasons are unknown for most species. One hypothesis to explain seasonal variation in the distributions of species...
When hosts have a long coevolutionary history with their parasites, fitness costs of chronic infection have often been assumed to be negligible. Yet, experimental manipulation of infections sometimes reveals effects of parasites on their hosts, particularly during reproduction. Whether these...
Winter in temperate regions is characteristically the coldest period of the year. Species in these regions adapt to freezing temperatures with physiological or behavioural mechanisms to mitigate the threats of cold exposure. For aquatic species, taking refuge under the ice...
Elevated lake chloride concentration has been observed in many regions, due to human activities such as mining, agriculture, and urbanisation. Meanwhile, lakes are also experiencing increasing frequency and intensity of heatwaves. The combination of elevated salinity and heatwaves has not...
When the shoot apical meristem of plants is damaged or removed, fecundity and/or plant growth may suffer (under-compensation), remain unaffected (compensation) or increase (overcompensation). The latter signifies a potential ‘cost’ of apical dominance. Using natural populations of 19 herbaceous angiosperm...
Plant competition experiments commonly suggest that larger species have an advantage, primarily in terms of light acquisition. However, within crowded natural vegetation, where competition evidently impacts fitness, most resident species are relatively small. It remains unclear, therefore, whether the size...
The trait compensation and cospecialization hypotheses make contrasting predictions on how boldness is co-adapted with antipredator defences. If trait compensation occurs, then bold individuals should be equipped with better antipredator defences to compensate for their increased risk exposure. By contrast...
Dispersal is one of the most fundamental components of ecology. Dispersal is also particularly relevant in an era of unprecedented habitat loss and climate change. We used a unique dataset to examine dispersal in gray ratsnakes (Pantherophis spiloides)...
Urbanisation and agriculture are paradigmatic cases of habitat loss, degradation, and fragmentation that imperil wildlife. Anthropogenic landscape modifications can harm species such as freshwater turtles that rely on both aquatic and surrounding terrestrial habitats to survive and reproduce. We tested...
Decontaminating recreational watercraft, and fishing, sailing or watersports equipment after use can reduce the overland dispersal of aquatic invasive species (AIS) among lakes. Recommended methods include pressure-washing, rinsing with hot water, using cleaning agents, or air-drying, but the extent of...
Although it is sometimes difficult for researchers to ensure that their work is used by resource managers to make informed decisions, an example where this knowledge–action gap has been breached is in research published in Aquatic Conservation: Marine and Freshwater...
Trade-offs shaping behavioral variation are often influenced by the environment. We investigated the role that the environment plays in mediating trade-offs using a widespread frog with a conspicuous mating display, Pseudacris crucifer. We first demonstrated, using playback and desiccation...
Habitat loss and fragmentation are among the greatest threats to wildlife and biodiversity. Reptiles are particularly susceptible to these threats due to high site fidelity, large home ranges, and slow movement rates. To understand behavioral responses of Eastern Milksnakes (...
We observed the number of basking female Graptemys geographica (northern map turtles) at 4 basking sites before and after controlled motorboat disturbances using time-lapse cameras. In the 6 hrs following disturbance, the mean number of turtles basking at a site...
Population decline and the threat of extinction are realities currently facing many species. Yet, in most cases, the detailed demographic data necessary to identify causes of population decline are unavailable. Using 43 years (1975−2017) of data from a box-nesting population of...
White-nose syndrome (WNS) has rendered four of Ontario’s species endangered, while leaving the other four species
relatively unaffected. The causes and extent of the declines have been widely studied. The influence on remaining bat species has
not. Comparing acoustic data...
In many species, individuals prefer mates that are genetically dissimilar at the major histocompatibility complex (MHC), likely because it improves offspring resistance to pathogens. Here, we provide the first characterization of the MHC class II peptide binding region in bluegill...
The blacklegged tick, Ixodes scapularis, is established in several regions of Ontario, Canada, and continues to spread into new geographic areas across the province at a rapid rate. This poses a significant public health risk since I. scapularis...
Parental care can include two general types of behavior: (1) aggressive behavior, which is used to defend offspring from predators; and (2) nurturing behavior, which is used to provide offspring with environmental conditions or resources necessary for survival. Many studies...
Bythotrephes longimanus is an invasive zooplankton predator, negatively impacting zooplankton abundance and diversity in North American lakes. Previous studies have shown that Daphnia populations in lakes move to deeper waters during the day, in the presence of Bythotrephes, a...
Shoaling is an evolved behavior in fishes that has several adaptive advantages, including allowing individuals to avoid predation through risk dilution. However, factors such as size disparity and the presence of heterospecifics may influence the behavior of individual fish within...
Many populations have intraspecific diversity in phenotype and ecological strategy, but the mechanisms maintaining such diversity are not fully understood. Multiple behaviors can be maintained either as a conditional strategy, where fitness depends on an individual’s phenotype, or as a...
Chemical signalling is widespread across animal taxa. Even birds, once thought to have little or no sense of smell, are now known to possess a fully functional olfactory system and may thus respond to conspecific and heterospecific chemical signals. In...
Larger numbers of colonists can be more likely to establish and spread due to the benefits provided by either more individuals (quantity) or a greater diversity of genotypes or phenotypes (genetic diversity). However, the value of higher colonist quantity or...
Stressed fish have been shown to have higher predator-induced mortality than unstressed conspecifics, suggesting a role for the hypothalamic–pituitary–interrenal axis in modifying risk-taking behaviors. Yet, there is also evidence of behavioral resiliency in the face of chronic stressors. Here, we...
The hypothalamic‐pituitary‐interrenal (HPI) or stress axis in teleost fishes produces their primary glucocorticoid, cortisol. Although generally an adaptive response, prolonged HPI axis stimulation can impair organismal performance. Previous work has shown that stressed teleosts have higher mortality to predation than...
Acute elevation of cortisol via activation of the hypothalamic-pituitary-interrenal (HPI) axis aids the fish in dealing with a stressor. However, chronic elevation of cortisol has detrimental effects and has been studied extensively in lab settings. However, data pertaining to wild...
We compared baseline and maximal cortisol concentrations between predator exposure and prey blood samples in pumpkinseed Lepomis gibbosus, captured using a standardised fishing event underneath osprey Pandion haliaetus nests and away from osprey nests. We did not detect differences...
Overwintering is a critical part of the annual cycle of animals living at high latitudes, and selection of overwintering sites (hibernacula) is important to population persistence. Identifying the overwintering sites of aquatic species is challenging in areas...
Overwintering is a critical part of the annual cycle of animals living at high latitudes, and selection of overwintering sites (hibernacula) is important to population persistence. Identifying the overwintering sites of aquatic species is challenging in areas where water bodies...
Research has identified numerous conservation benefits attributed to the use of marine protected areas (MPAs), yet comparatively less is known about the effectiveness of freshwater protected areas (FPAs).
This study assessed multiple long‐standing (>70 years active) intra‐lake FPAs in three...
Individual variation in parasite defences, such as resistance and tolerance, can underlie heterogeneity in fitness and could influence disease transmission dynamics. Glucocorticoid hormone concentrations often change in response to fluctuating environmental conditions and mediate changes in immune function, resource allocation...
Research in a variety of vertebrate taxa has found that cardiac function is a major limiting factor in the ability of animals to cope with physiological challenges, and thus is suggested to play an important role in mediating fitness-related behaviors...
Larger plants of course generally produce more seed offspring than smaller plants. The vast majority of species, however (and resident reproductive plants within a given species’ population), are relatively small. To help interpret why this may be so, we controlled...
In migratory animals, the degree to which individuals return to the same wintering sites across multiple years can affect fitness and population dynamics, and thus has important implications for conservation. Despite this, long-term evaluations of wintering-site fidelity are rare for...
Various aspects of performance (e.g., speed, strength, endurance) are thought to be important determinants of the success of animals in natural activities such as foraging, mating, and escaping from predators. However, it is generally known that morphological properties enhancing one...
As species shift their ranges and phenology to cope with climate change, many are left without a ready supply of their preferred food source during critical life stages. Food shortages are often assumed to be driven by reduced total food...
According to the traditional “Size Advantage” (SA) hypothesis, plant species with larger body size are expected to be more successful when competition is intense, that is, within severely crowded vegetation. Recent studies in old‐field habitats, however, have shown that those...
Water availability is a primary regulator of plant productivity and species richness in arid and semi‐arid ecosystems, but its influence in other habitats is much less clear partly because experimental manipulations of water are relatively rare. How important is...
Although many fish are captured and released following hook removal by recreational anglers, some fish break the line and are confronted by the potential impediment of a lure lodged in the jaw, buccal cavity, or throat. We simulated break-off events...
Chemical signaling has been well studied in invertebrates and mammals but less so in birds, due to the longstanding misconception that olfaction is unimportant or even non-existent in this taxon. However, recent findings suggest that olfaction plays an important role...
Reproduction is an energetically demanding life history stage that requires costly physiological and behavioral changes, yet some individuals will invest more into reproduction and breed more successfully than others. To understand variation in reproductive investment, previous studies have evaluated factors...
In vertebrate animals, genes of the major histocompatibility complex (MHC) determine the set of pathogens to which an individual's adaptive immune system can respond. MHC genes are extraordinarily polymorphic, often showing elevated nonsynonymous relative to synonymous sequence variation and sharing...
The immunosuppressive effects of androgens are a key component of the immunocompetence handicap hypothesis (ICHH). Here, we use bluegill sunfish (Lepomis macrochirus) to test two predictions arising from this hypothesis: (1) natural circulating concentrations of the androgen 11-ketotestosterone...
Fish sedation facilitates safer handling of fish during scientific research or fisheries assessment practices, thus limiting risk of injury to fish and reducing stress responses. In recent years, there has been growing interest in using electricity to sedate fish; two...
Bird species around the world are threatened with extinction. In North America, aerial insectivores are experiencing particularly severe population declines. To conserve these species, we need to know which life stages have the largest influence on population growth. We monitored...
The hypothalamic-pituitary-interrenal (HPI) axis is centrally implicated in stressor mitigation in teleost fishes. Sustained HPI axis activation can be detrimental to the physiological functioning of an organism and can result in fitness-related trade-offs. Predator-induced mortality is known to be higher...
Recreational boating activity has the potential to generate noise pollution that may influence wild fish. Such noise may be particularly relevant to fish engaged in parental care (PC), where alterations in behaviour could influence individual fitness and productivity of fish...
Closely related species with overlapping geographic ranges encounter a significant challenge: they share many ecological traits and preferences but must partition resources to coexist. In Ontario, potentially eleven species of carrion beetles (Coleoptera: Silphidae) live together and require vertebrate carrion...
Populations are often spatially structured such that phenotype distributions reflect adaptive phenotype-habitat associations. I investigated two questions about how environmental heterogeneity contributes to spatially structured phenotypic variation in a polyphenic population of sunfish. 1) How does sunfish habitat use in...
Glucocorticoid hormones allow individuals to rapidly adjust their physiology and behavior to meet the challenges of a variable environment. An individual’s baseline concentration of glucocorticoids can reflect shifts in life history stage and resource demands while mediating a suite of...
