Daniel Gallant

Parks Canada · Kouchibouguac National Park

Rapid range expansion of boreal forest predators onto the tundra may disrupt local ecological processes, notably through competition with ecologically similar species. Red foxes (Vulpes vulpes) have expanded their range northwards throughout the Canadian Arctic, inducing competition with endemic Arctic foxes (V. lagopus). We studied competition bet...

High levels of biodiversity may be needed to maintain ecosystem functioning. By creating niches for other species, ecosystem engineers have the potential to promote biodiversity, but it is unclear how this translates across spatiotemporal scales. We evaluated the long-term impact of ecosystem engineering by beavers ( Castor canadensis ) on the dive...

The poleward range shift of the red fox (Vulpes vulpes) >1700 kilometers into the Arctic is one of the most remarkable distribution changes of the early 20th century. While this expansion threatens a smaller arctic ecological equivalent, the arctic fox (Vulpes lagopus), the case became a textbook example of climate‐driven range shifts. We tested th...

Climate change can have a marked effect on the distribution and abundance of some species, as well as their interspecific interactions. In 1992, before ecological effects of anthropogenic climate change had developed into a topical research field, Hersteinsson and Macdonald published a seminal paper hypothesizing that the northern distribution limi...

Assessing the scale of ecological changes that have occurred since the onset of the Anthropocene is challenging. One major problem is that of shifting baselines, whereby the norms we set for judging the state of species, populations, or ecosystems change over time due to incomplete information. Here we show how data mining can be used to fill some...

According to optimal foraging theory, consumers make choices that maximize their net energy intake per unit of time. We used foraging theory as a framework to understand the foraging behaviour of beavers (Castor canadensis Kuhl, 1820), an important herbivore that engineers new habitats. We tested the hypothesis that beavers are energy maximizers by...

En créant et maintenant des habitats hétérogènes, certaines espèces ont une influence disproportionnée sur les écosystèmes qu’elles occupent. Étant donné la crise d’extinction actuelle, comprendre l’impact de ces ingénieurs d’écosystèmes sur la biodiversité constitue une priorité. Par la construction de barrages et l’abatage d’arbres, les castors m...

By creating and maintaining heterogeneous habitats, some species have a disproportionate influence on ecosystems where they occur. Given the current extinction crisis, understanding the impact of these ecosystem engineers on biodiversity constitutes a priority. By cutting trees and building dams, beavers drastically modify riparian landscapes, and...

The red fox (Vulpes vulpes) expanded its distribution over large parts of the Canadian Arctic during the twentieth century and is now considered a threat to the arctic fox (Vulpes lagopus). Some authors have proposed that the European red fox, introduced in Eastern North America during the eighteenth century, may have spread and caused the species’...

In the twentieth century, red fox (Vulpes vulpes) expanded into the Canadian Arctic, where it competes with arctic fox (Vulpes lagopus) for food and shelter. Red fox dominates in physical interactions with the smaller arctic fox, but little is known about competition between them on the tundra. On Hershel Island, north Yukon, where these foxes are...

During the last century, the red fox (Vulpes vulpes) has expanded its distribution into the Arctic, where it competes with the arctic fox (Vulpes lagopus), an ecologically similar tundra predator. The red fox expansion correlates with climate warming, and the ultimate determinant of the outcome of the competition between the two species is hypothes...

It is now well documented that Arctic climates and ecosystems are changing at some of the fastest rates on planet Earth. These changes are significant for all Arctic biodiversity, and they are a great challenge for cooperative management boards of Canada's Arctic national parks, those legislated to maintain or improve the ecological integrity of al...

Habitat preferences of river otters (Lontra canadensis (Schreber, 1777)) are well known, but because most studies were conducted in regions with markedly low or high levels of anthropogenic disturbances, it is not well known how their habitat usage is affected by varied anthropogenic disturbances and land-use regimes on a regional scale. We studied...

We used surveys of arctic and red fox dens performed over a 38-year period in the northern Yukon to test the general hypothesis that northern species are displaced by their southern competitors due to climate warming. Our regional data do not fit this hypothesis. Even when generally accepted, hypotheses in ecology must be applied with care to speci...

We describe a rare observation of reciprocal aggression between two river otters (Lontra canadensis) and a beaver (Castor canadensis). Our observations and other literature accounts suggest that the relationship between these species may not be the commensal onesuggested by some researchers. Because information on otter-beaver interactions in the l...

Many researchers use bridges as search sites to monitor freshwater otter species along watercourses. Bridges enable rapid and easy access to their habitat, but for most otter species little is known on whether these anthropogenic structures affect their distribution, their marking preferences, and consequently, the ability of such surveys to detect...

River otters (Lontra canadensis (Schreber, 1777)) and beavers (Castor canadensis Kuhl, 1820) are semi-aquatic mammals that can occur sympatrically in freshwater ecosystems of North America, including beaver ponds. Although little research has been done on the relationship between these species, it has been described as commensal. Relatively little...

Some species of otters have been much more studied than others. A particular challenge in the management and conservation of otters worldwide is that some of the lesser-known species are also among those being the object of conservation concerns. In this paper, I argue about the importance of producing more scientific knowledge about lesser-known o...

We examined the relationship between the production of sites with feces (i.e., latrines) and river otter (Lontra canadensis) abundance to determine whether scat surveys were adequate for monitoring relative population size for species leaving activity signs in a clumped distribution on the landscape. We conducted winter riparian transects to simult...

For the last 40 years, the presence of Cougars (Puma concolor) in eastern Canada has been highly controversial. The purpose of this study was to collect physical evidence of Cougars using a passive detection method. Baited hair-traps combined with camera-traps were installed in New Brunswick and Nova Scotia, Canada. DNA analyses on two hair samples...

Le Parc national du Canada Kouchibouguac se base présentement sur trois critères pour permettre ou interdire la récolte des myes communes (Mya arenaria) au sein des bancs à l’intérieur de ses frontières. Pour être ouvert à l’exploitation, un banc doit avoir au une densité moyenne minimum de 100 myes/m2 (critère A), une proportion minimum de 0,10 de...

The objective of this study was to examine the foraging behaviour of the beaver (Castor canadensis Kuhl, 1820) and to explain its selection of terrestrial woody plant species according to central place foraging theory. Limitations in variety of food items in most studies with regard to size and (or) distance from the central place and information o...

Instances of coprophagy by birds are rare in comparison to coprophagy by other animals such as mammals and insects. Here, I report on White-winged Crossbills (Loxia leucoptera) obtaining forage from river otter (Lontra canadensis) feces in Kouchibouguac National Park, New Brunswick, Canada. In sequence, two male White-winged Crossbills landed on a...