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...
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...
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...
Fish are commonly sedated to render them immobile and thus easier to handle for research, veterinary, and aquaculture practices. Since sedation itself imposes a significant challenge on the targeted fish, the selection of sedation methods that minimize physiological and behavioral...
After a fish snaps an angler’s line, the hook(s) still embedded in its mouth, the question arises: what will the encounter cost the fish? The consequences of retained gear on the physiology and behaviour of fish is not well understood. This...
Paternal care, where the male provides sole care for the developing brood, is a common form of reproductive investment among teleost fish and ubiquitous in the Centrarchidae family. Throughout the parental care period, nesting males expend energy in a variety...
Ecological light pollution occurs when artificial lights disrupt the natural regimes of individual organisms or their ecosystems. Increasing development of shoreline habitats leads to increased light pollution (e.g., from cottages, docks, automobile traffic), which could impact the ecology of littoral...
To generate mortality estimates for fish that are captured and released in recreational and commercial fisheries, it is common to temporarily hold fish in captivity. Typically, captured fish are placed in some form of pen, cage or tank with control...
Characterizing the genetic and behavioural consequences of contact between previously geographically isolated lineages provides insights into the mechanisms underlying diversification and ultimately speciation. The spring peeper (Pseudacris crucifer) is a widespread Nearctic chorus frog with six divergent mitochondrial...
Current methods of fish epithelial injury detection are limited to gross macroscopic examination that has a subjective bias as well as an inability to reliably quantify the degree of injury. Fluorescein, a presumptive test for blood, has been shown to...
Conspicuous ornamentation has been linked to immunological and physiological condition in males of many species. In species where both sexes are ornamented, it is unclear whether the signal content of ornaments differs between males and females. We examined the immunological...
The glucocorticoid (GC) stress response is thought to be an individual trait associated with behaviour and life history strategies. Studies exploring such relationships typically assume measured hormone values to be repeatable within an individual. However, repeatability of GCs has proven...
Size-selective harvesting associated with commercial and recreational fishing practices has been shown to alter life history traits through a phenomenon known as fishing-induced evolution. This phenomenon may be a result of selection pathways targeting life-history traits directly or indirectly through...
While social interactions influence vertebrate endocrine regulation, the dynamics of regulation in relation to specific behaviors have not been clearly elucidated. In the current study, we investigated whether androgens (testosterone) or glucocorticoids (cortisol) play a functional role in aggressive offspring...
According to traditional theory, superior competitive ability in plants generally requires relatively large plant body size. Yet even within the most crowded vegetation, most resident species are relatively small; species size distributions are right-skewed at virtually every scale. We...
Many fish species respond to low temperature by inducing mitochondrial biogenesis, reflected in an increase in activity of the mitochondrial enzyme cytochrome c oxidase (COX). COX is composed of 13 subunits, three encoded by mitochondrial (mt)DNA and 10 encoded by...
Parental care is an energetically costly period of the life history of many fish species characterized by extended high intensity activity. To date, there have been no studies that have investigated the cardiovascular correlates of extended parental care in fish...
We examined whether male plumage coloration signals parental quality in the American Redstart (Setophaga ruticilla), a highly ornamented, migratory warbler. We measured the relationship between both adult male arrival date and phenotype (morphology, melanin- and carotenoid-based plumage), and...
Dingemanse et al. suggest that the Cort-Fitness Hypothesis rests upon the idea that ‘the optimal level of resources allocated towards self-maintenance (immediate survival) versus long-term survival and/or reproduction differs across environments, with selection favoring individuals investing in self-maintenance when the...
The energetic and physiological status of parental smallmouth bass Micropterus dolomieu was investigated across the majority of their latitudinal range at the onset and near the end of care. Variables such as tissue lipid stores, plasma indicators of nutritional status...
Sperm swimming speed is an important determinant of male fertility and sperm competitiveness. Despite its fundamental biological importance, the underlying evolutionary processes affecting this male reproductive trait are poorly understood. Using a comparative approach in a phylogenetic framework, we tested...
When break-offs occur during recreational angling, lures may be retained by the fish. To date, there have been few studies on the consequences of lure retention on sportfish. This study evaluated how the retention of three different types of lures...
Research on a wide range of fish species has revealed that deep hooking is perhaps the single most important determinant of injury and post-release mortality in recreational fisheries. However, there is little information on the best option for dealing with...
We present and compare demographic data for cerulean warblers (Dendroica cerulea) from 5 study sites across the range of the species from 1992 to 2006. We conducted field studies to collect data on daily nest survival, nest success...
Increasing anthropogenic pollution from urban centers and fossil fuel combustion can impact the carbon and nitrogen cycles in forests. To assess the impact of twentieth century anthropogenic pollution on forested system carbon and nitrogen cycles, variations in the carbon and...
Many animals exhibit pronounced shifts in ecology (e.g., habitat use, diet) as they grow. The central goal of this study was to determine whether habitat use and movement patterns of juvenile black ratsnakes (Elaphe obsoleta) differed from patterns...
Blue‐winged (Vermivora pinus) and golden‐winged warblers (Vermivora chrysoptera) have an extensive mosaic hybrid zone in eastern North America. Over the past century, the general trajectory has been a rapid replacement of chrysoptera by pinus in a...
Understanding the causes of variation in feather colour in free-living migratory birds has been challenging owing to our inability to track individuals during the moulting period when colours are acquired. Using stable-hydrogen isotopes to estimate moulting locality, we show that...
Birds meet the energetic demands of egg formation by using either endogenous reserves (capital breeding) or recently ingested nutrients (income breeding). Examining these strategies in migratory birds has been difficult because of the inability to assign the origin of egg...
Organismal performance curves are important functions for the study of reptilian ecology and evolution, but their interpretation can be affected strongly by the choice of analytical approach. We first use an example from the literature to demonstrate that excluding biologically...
There are two prominent, nonmutually exclusive hypotheses to explain the timing of reproduction in animals: energetic constraint and adaptive behaviour.
We tested these hypotheses by quantifying the costs and benefits of nesting at different times in the season for male...
Freshwater environments are currently experiencing an alarming decline in biodiversity. As a result, scientists and managers must look for alternative management techniques to protect these aquatic systems. One such option that has potential to protect freshwater environments from numerous threats...
Conservation biologists increasingly face the need to provide legislators, courts and conservation managers with data on causal mechanisms underlying conservation problems such as species decline. To develop and monitor solutions, conservation biologists are progressively using more techniques that are physiological...
Three southeastern Ontario lakes have responded differently to human disturbances in their catchments over the past 150 years. Catchments of Round and Long lakes were once subjected to deforestation and apatite mining but currently have no local watershed disturbances. Meanwhile...
The two-note fee-bee song of male black-capped chickadees functions during the dawn chorus, in part, as a sexual signal across large distances. How song structure might encode information about male quality, however, remains unclear. We studied the availability of cues...
Nonequilibrium conditions due to either allopatry followed by secondary contact or recent range expansion can confound measurements of gene flow among populations in previously glaciated regions. We determined the scale at which gene flow can be estimated among breeding aggregations...
In this study we examined the effects of exhaustive exercise and brief air exposure on the cardiovascular function of largemouth bass Micropterus salmoides at four water temperatures (13, 17, 21, and 25°C). We used Doppler flow probes to monitor cardiac...
We present direct experimental evidence of pheromone use in six species of Arrenurus and indirect evidence for four species, including members of the subgenera Megaluracarus, Truncaturus, and Arrenurus. Water in which females were housed elicited arrestant behaviour in...
This study investigated how demographic characteristics of black rat snakes Elaphe obsoleta are affected by the length of the active season, and also used the resulting demographic data to determine the proximate factors responsible for male‐biased sexual size dimorphism (SSD)...
Paleolimnological analysis of microfossils and physical sediment characteristics in 210Pb and Ambrosia dated sediment cores, along with diatom-inferred total phosphorus concentration [TP] reconstructions, were used to determine the trophic histories (ca 200 years) of four lakes within the Rideau Canal...
Intra- and interspecific contact rates of 12 adult (five females, seven males) raccoons (Procyon lotor) were recorded while these animals fed at a rural garbage dump 40 km north of Kingston, Ontario, Canada from 15 June to 5...
We provide evidence for conspecific acoustic communication in caterpillars. Larvae of the common hook-tip moth, Drepana arcuata (Drepanoidea), defend silk nest sites from conspecifics by using ritualized acoustic displays. Sounds are produced by drumming the mandibles and scraping the mandibles...
Mean daily mobility estimates for smallmouth bass Micropterus dolomieu from mark‐recapture (47·5±12·5 m) were less than from conventional telemetry (77·1±10·6 m). The relationship developed in a respirometer between the activity transmitter and swimming speed (r2=0·99, P < 0·001, ...
Chironomid (Diptera: Chironomidae) head capsules were studied from a core of recent sediments from shallow, macrophyte-dominated Lake Opinicon, Ontario, Canada, to determine if assemblages have changed in response to lake-level changes and other watershed disturbances, including deforestation and agriculture. Our...
The fitness consequences of self‐fertilization are largely determined by how self‐pollination occurs. Within‐flower self‐pollination (autogamy) may be advantageous, since it can provide reproductive assurance without much seed or pollen discounting. In contrast, between‐flower self‐pollination (geitonogamy) provides no reproductive assurance and...
Extra-pair paternity is common in many socially monogamous passerine birds with biparental care. Thus, males often invest in offspring to which they are not related. Models of optimal parental investment predict that, under certain assumptions, males should lower their investment...
Male birds are often faced with low confidence of paternity in their mates' offspring, raising the question of how paternal care covaries with confidence of paternity. We tested the hypothesis that male eastern bluebirds (Sialia sialis) reduce care...
The influence of frequent water-column mixing on phytoplankton succession and species composition was studied by comparing plankton dynamics in two lakes (Lake Opinicon and Upper Rock Lake) which have similar water chemistry, but differ widely in their basin morphometries: Opinicon...
Larval damselflies resist infestation by parasitic larval mites by exhibiting behaviours such as grooming, crawling, swimming, and striking at host-seeking mites. Larval damselflies are known to increase time spent in these behaviours in the presence of mites but reduce time...
There is growing evidence that many self‐compatible plants control the level of self‐fertilization with postpollination processes that give a siring advantage to cross pollen over self pollen through “cryptic self‐incompatibility” (CSI). Previous marker‐gene experiments with self‐compatible, tristylous Decodon verticillatus (Lythraceae)...
Phosphorus pratense (Poaceae) has been shown to reduce pollen germination and seed set of heterospecific Poaceae. Danthonia compressa has a mixed breeding system, ie , both cleistogamous and chasmogamous florets. Previous studies revealed that extracts from 1-5 pollen grains of P...
Theory suggests that a male strategy of reducing parental care in response to reduced parentage should evolve only under certain conditions. Expected paternity in subsequent matings is predicted to be primary in effect, because it determines whether there is a...
The dynamics of chrysophyte populations and the onset of encystment in relation to several physical, chemical, and biological variables were studied in two Canadian lakes, Lake Opinicon (LO) and Upper Rock Lake (URL). LO is shallow and polymictic during the...
If cavity-entrance orientation confers some benefit to secondary hole-nesting birds, individuals should use cavities with certain entrance orientations, and the orientation of a cavity's entrance should influence reproductive success.
Previous studies provide evidence that cavity size influences clutch-size and reproductive success in some hole-nesting birds, because overcrowding in cavities may cause brood mortality due to trampling or hyperthermia. We tested this hypothesis with two experiments at nestbox populations of...
We removed the mates of ten male blackcapped chickadees (Parus atricapillus) during the nestbuilding period to determine the effect of female presence on dawn singing. During the first dawn chorus following mate removal, males sang significantly longer, increased movement within...
