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...
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...
Context: Identifying key spatio–temporal periods of an organism’s activity is an important focus of many ecological studies. Bat activity, as assessed by passive acoustic monitoring, can be extremely variable and currently there exists no agreed-upon method for identifying periods of...
A central tenet of ecoimmunology is that an organism's environment shapes its optimal investment in immunity. For example, the benefits of acquired (relatively pathogen specific) versus innate (nonspecific) immune defenses are thought to vary with the risk of encountering familiar...
The United Nations’ (UN) 2030 Agenda for Sustainable Development defines the formidable challenge of integrating historically separate economic, social, and environmental goals into a unified ‘plan of action for people, planet, and prosperity.’ We highlight the substantial contribution inland fisheries...
The concept of behavioural syndromes (i.e. correlations between behavioural traits) has provided an important framework for understanding individual variation in animal behaviour and its link to individual variation in physiology and life-history traits. The pace-of-life syndrome concept posits that behavioural, physiological...
One of the primary factors associated with mortality in catch-and-release recreational fisheries is depth of hook position relative to the snout, with deeper hooking locations (i.e., gullet) increasing risk of injury to vital tissues. As a result, there have been...
To date, most studies of commercial fisheries bycatch have focused on mortality at time of capture as an endpoint. However, sub-lethal indicators of organismal condition have the potential to reveal mechanisms associated with mortality (both at time of capture and post-release)...
Catch and release is a common practice among recreational anglers. In instances when fish are deeply hooked, the proper techniques for promoting survival are poorly understood, although evidence suggests that the fishing line should be cut rather than attempting to...
As the number of invasive species increases globally, more and more native predators are reported to shift their diet toward invasive prey. The consequences of such diet shifts for the health of populations of native predators are poorly studied, but...
As the number of invasive species increases globally, more and more native predators are reported to shift their diet toward invasive prey. The consequences of such diet shifts for the health of populations of native predators are poorly studied, but...
Advances in research on bird vocalizations often follow the development of new recording technologies and analytical techniques (Baptista & Gaunt 1994, Baker 2001). As recently as a decade ago, ornithologists recorded birdsong onto magnetic tape and analysed sounds with a...
Sexual size dimorphism (SSD) is a common phenomenon in animals. In many species females are substantially larger than males. Because body size plays a central role in modulating the body temperature (Tb) of ectotherms, intersexual differences...
Recreational power boating is growing in popularity in North America. This activity is known to have lethal and sub-lethal effects on aquatic wildlife and freshwater turtles may be particularly sensitive to this activity. This study reports on patterns of traumatic injuries inflicted by powerboat propellers...
The continued popularity of angling for largemouth bass Micropterus salmoides and smallmouth bass M. dolomieu has led to concerns about the effects it may have on fish populations, including the realized fitness of individuals. Although catch‐and‐release angling and its effects...
Predation risk has the ability to greatly influence the behaviour of reproducing individuals. In large long‐lived species with low risk of predation for parents, reproductive behaviours often involve caring for offspring (i.e. defending broods from predators) and these behaviours are...
Insects can resist parasites using the costly process of melanotic encapsulation. This form of physiological resistance has been studied under laboratory conditions, but the abiotic and biotic factors affecting resistance in natural insect populations are not well understood. Mite...
Sexual dimorphism in body size and in trophic morphology are common in animals and are often concordant with patterns of habitat use and diet. Proximate factors leading to intersexual differences in habitat use, however, are challenging to unravel because these...
Because fish are poikilothermic, water temperature is regarded as a primary factor influencing their activity and behaviour. Rarely have field studies been conducted with the spatiotemporal resolution to enable rigorous quantitative assessments of that relationship. Furthermore, there have been few...
Spermatozoa are among the most diversified cells in the animal kingdom, but the underlying evolutionary forces affecting intraspecific variation in sperm morphology are poorly understood. It has been hypothesized that sperm competition is a potent selection pressure on sperm variation...
Sperm competition occurs when the sperm of more than one male compete to fertilize the eggs of a female. In reptiles, sperm competition is particularly prevalent and is an important agent of sexual selection in males. Spermatogenesis in reptiles can...
Male bluegill sunfish (Lepomis macrochirus) exhibit alternative life histories: some males (parentals) delay maturation for up to 7 yr, then build nests, court females, and care for the eggs and fry, whereas other males (cuckolders) mature precociously, attempt to...
Hook size is an important consideration in the use of circle hooks as a conservation tool for minimizing the injury and mortality of marine fishes, but little is known about the role of hook size in the performance of hooks...
Males of many species are characterized by alternative mating tactics. In bluegill sunfish (Lepomis macrochirus), some males delay maturation and become “parentals” while other males mature precociously and become “cuckolders.” Parentals use an overt, territorial mating tactic, defending...
Tackle manufacturers have responded to concerns regarding hooking injury and mortality by attempting to design and market hooks that are less damaging to fish (e.g., circle hooks). To date, studies investigating circle hooks have been primarily restricted to large marine...
We obtained molecular markers useful for population level studies of the black rat snake (Elaphe obsoleta) by screening genomic DNA libraries enriched for dinucleotide, tetranucleotide, and pentanucleotide microsatellite repeats. Following sequencing of the positive clones, 11 pairs of...
Variation in immune responsiveness within and among species is the subject of the emerging field of ecological immunology. The work reported here showed that individuals of Lestes forcipatus Rambur differ in their likelihood of mounting immune responses, and in the...
Gene flow is fundamental to evolutionary processes but knowledge about movements of individuals and their offspring necessary for gene flow is scant. We investigated potential ecological components of genetic connectivity within a population of black rat snakes (Elaphe obsoleta...
Sociality is associated with increased risks of parasitism, predation, and social competition, which may interact because social stress can reduce immunity, and parasitized individuals are more likely to fall prey to a predator. A mechanism allowing evolution of sociality in...
It has been proposed that the most sensitive auditory receptor cell (A1) in the two-celled ears of certain noctuoid moths is inhibited by its partner, the A2 cell, at high stimulus intensities. We used the single-celled ears of notodontid moths...
Pollen allelopathy occurs when pollen toxins inhibit sexual reproduction in heterospecifics. To quantify pollen allelopathic effects in vitro, pollen of Hieracium autrantiacum, H. Floribundum and H. Pratense was extracted with double distilled water into concentrationss of pollen grains.
This study examines the maintenance of inbreeding depression impartially self-fertilizing populations of the long-lived, herbaceous wetland plant, Decodon verticillatus.
In phoebes, parents of small first broods are able to raise nestlings in better condition. We predict that in harsh years, parents of small first broods would be more likely to renest. Parents of enlarged first broods sacrificed quality of...
Evidence from a variety of sources, including commercial harvesters, Ministry of Natural Resources census data, and field studies, indicates that Bullfrogs in Ontario are less common now than they were in previous decades, and larger ones are particularly hard to...
Individual variation in the foraging behaviour of the pumpkinseed sunfish was investigated under laboratory conditions in feeding arenas containing structured and open-water habitats. In general, fish learned to feed on a novel prey item over a 10-day period with both...
The recognition that infanticide, the killing of conspecific young, can hasten or even create a breeding opportunity for the infanticidal adult, has elevated the behavior from pathological to sexually selected.
Laboratory-reared first-instar juvenile Gerris comatus Drake & Hottes, Gerris alacris Hussey, and Gerris buenoi Kirkaldy were exposed to larval Limnochares aquatica (L.). Development and mortality of parasitized juvenile water striders were monitored and compared with those of unparasitized insects. Duration...
The ideal dominance distribution model predicts that competition between individuals of a species for territories will result in socially dominant individuals acquiring territories in higher quality habitat than their subordinates. Although the dispersion and relative reproductive success of male red-winged...
Largemouth bass Micropterus salmoides were reared over their first 8 weeks of free‐swimming life in uncontaminated control water or in water containing one of five concentrations of pentachlorophenol (PCP) ranging from 1.6 to 88 μg/L. Over the final 3...
Individual male Yellow Warblers (Dendroica petechia) exhibit differences in their level of parental investment, which correlate with the amount of brown streaking on the breast. We tested two alternative hypotheses to explain these patterns. The age effect hypothesis...
We conducted laboratory experiments to determine if juveniles of three species of centrarchid fishes displayed abilities for species or individual recognition. In one experiment we reared rock bass (Ambloplites rupestris) in social isolation and in social groups. Both...
We compared the ontogeny of feeding in two centrarchid species and hypothesised that the ontogeny of early feeding in the black crappie, Pomoxis nigromaculatus, would differ from that of the smallmouth bass, Micropterus dolomieui, and that the smaller...
The implications of chemosensory feeding and associated ictalurid morphology were investigated through a seasonal study of the diets of the brown bullhead (Ictalurus nebulosus) and yellow bullhead (I. natalis) relative to food availability. Based on...
The use of other individual's echolocation calls by little brown bats, Myotis lucifugus, was tested by observing the response of fi'ee-flying bats to presentations of recorded echolocation calls and artificial sounds. Bats responded by approaching conspecific calls while searching...
Lake Opinicon in southeastern Ontario contains 57 islands.In 1963 deer mice were found on 20 of these, in populations of one to 50. Fewer islands had mice in 1964,but two of these had much higher populations than in 1963. Mice...
Populations of the adult insects which emerged from Lake Opinicon, Ontario, were sampled by emergence traps from July 1-11, 1951. The average daily emergence per square meter of lake surface was 136 insects which had a fresh weight of 69.2...
