Group selection has recently emerged as an alternative silvicultural system to clearcutting in Appalachian hardwood forests, but there is little, if any, information on the effects of group selection on wildlife. Thus, I studied and compared the effects of group selection and clearcut openings on wildlife in the Jefferson National Forest, Virginia. Breeding birds were censused 1 year before and 2 years after harvesting at 20 group selection openings, 4 clearcut openings, 18 sites in the mature even-aged forest adjacent to the openings, and 29 control sites. I also compared use of group selection openings and clearcut openings by white-tailed deer. The number of species and the total number of birds decreased at the openings and in the forest adjacent to the openings after harvesting with both methods. (Seven species increased and 9 species decreased in the openings after harvesting. Four species decreased in the forest adjacent to the openings after harvesting. Indigo buntings and rufous-sided towhees increased more at the interior of clearcut openings than at the edge of clearcut openings or in group selection openings. Sites within the clearcut openings where groups of trees were left uncut were not used more by birds than clearcut sites without trees. (The number and proportion of stumps with sprouts browsed by white-tailed deer was greater in group selection openings than in clearcut openings. Clearcut and large group selection openings provided breeding habitat for the same bird species. The smaller group selection openings were not used by some species found in the clearcut openings. However, creating a variety of opening sizes probably will provide the maximum benefit for all wildlife species that use early successional habitat. The same species were negatively affected, and to a similar degree, by group selection and clearcut openings. Both types of openings had negative impacts on forest-interior bird species in the adjacent forest. However, if the same acreage is harvested, group selection will affect a greater area of adjacent forest than clearcutting, because smaller openings have greater edge to area ratios. / Ph. D.

White-tailed deer (Odocoileus virginianus) are a highly charismatic game species with considerable ecological and economic impacts across most of their range. In the Central Appalachian Mountains, deer are a keystone species in forested ecosystems. Regionally, populations vary in herd growth or decline. These fluctuations are important in that they often drive many aspects of population management and regulation, which are dependent on herd demographics. Some key population vital rates allowing better understanding of these changes in white-tailed deer herds are survival, cause-specific mortality, home-range variation, both broad and fine-scale resource selection, and ultimately population growth trends in response to changes in both population vital rates and hunter harvest regulations. In this study, I address each of these concepts within a deer population in Bath County, Virginia, that has presumably been in overall decline since the early 1990's. From June-September, 2019-2020, I monitored survival and cause specific mortality of 57 neonate white-tailed deer until 12 weeks of age. Fawn and adult female survival was 0.310 (95% CI = 0.210-0.475) and 0.871 (95%CI=0.790-0.961) respectively. During the study, I observed a total of 37 fawn mortalities and identified the cause of death using field evidence and through analyzing genetics from residual predator salvia recovered on deer carcasses. Mortalities included 28 predation events and 9 deaths from other causes (e.g., abandonment, malnutrition, or disease). Black bears accounted for 48.6% of all mortality and 64.2% of known predations within our study. My top model identified elevation as a significant predictor of fawn survival, with mortality risk increasing 20% for every 100m increase in elevation. My model using observed vital rates predicted an increasing population of λ = 1.10 (interquartile range, IQR 1.06-1.14). The population was predicted to increase by 2% with a 10% increase in doe harvest (λ = 1.02, IQR = 0.97-1.06) but declined by 7% at 20% harvest (λ = 0.93, IQR = 0.89-0.96). I found that fawning home ranges of females that successfully reared fawns to the end of the season had significantly larger home ranges than those that were unsuccessful at higher elevations. Fawning home ranges for females with fawns increased approximately 71ha in size for every 100m increase in mean home range elevation, whereas seasonal home ranges of females without fawns decreased approximately 1.5 ha for every 100m increase in mean home range elevation. Deer selected fawn-rearing areas nearer to forested edges, open habitats, and at higher elevations, while they avoided areas near disturbed and mature forests. Within the fawn rearing area, females selected locations closer to disturbed forest, open habitats, and forested edge, while avoiding mature forest habitats, and higher elevations. Females selected birth sites with higher levels of visual obstruction. Using a step-selection method for real-time resource selection across biological seasons, we found that female deer selected for open areas during the fawning, breeding, early gestational, and late gestational seasons. During the fall breeding season, females avoided forested edge, but selected for areas at higher elevations. During early gestational seasons females selected disturbed habitats and areas at higher elevations while again avoiding forested edge. Overall, my work highlights variations in population dynamics of white-tailed deer in areas of the Central Appalachian Mountains that are primarily characterized by poor habitat quality and provides novel insights into fine-scale spatial ecology of female deer across biological seasons within the region. Ultimately, while the deer population in our study was not predicted to be in decline, this work supports predation risk as being a significant factor associated with habitat quality. / Doctor of Philosophy / White-tailed deer (Odocoileus virginianus) are a game species with extensive ecological and economic impacts across most of their range. In the central Appalachian Mountains, many populations across the region vary in terms of herd size growth, stability, or decline. These fluctuations are important in that they often drive many aspects of population management and regulation, which are dependent on the status of herd demographics. Some key population vital rates that aid us in better understanding these changes in white-tailed deer herds are survival and cause-specific mortality, home-range variation in association with habitat quality and the ability to successfully reproduce, population trends under hypothetical management scenarios, and resource selection of various habitats that are available across the landscape. In this study, I address each of these concepts within a deer population in Bath County, Virginia, which has presumably been in decline since the early 1990's. As expected, fawn survival was lower than previously reported from other study areas of the Central Appalachians Mountains. Predation was the leading cause of fawn mortality, with black bears being responsible for most predation events. Fawn mortality risk was significantly associated with elevation - where fawns at higher elevations were those at greater risk. Surprisingly, the deer population in Bath County was projected to be increasing under current conditions and was also projected to be stable-to-increasing even under some hypothetical scenarios which would negatively impact population growth (i.e., 10% increase in female harvest or 17% reduction in fawn survival). Fawning home ranges of collared females which successfully reared known fawns to the end of the biological season were significantly influenced by elevation; such that females with fawns had home ranges that increased in size with increasing elevation, whereas females without fawns had home ranges which decreased slightly in size with increasing elevation. At birth sites, females selected locations characterized by higher levels of visual obstruction compared to randomly sampled areas. Of the habitat types analyzed, both selection or avoidance of specific habitats varied across both biological season and spatial scale. Ultimately, while I found that some deer populations associated with poor quality habitats in the Central Appalachians may not be in decline, deer were likely influenced greatly by habitat quality – especially pertaining to predation risk – throughout Bath County.

Deer (<i> Odocoileus </i> spp.) are an important cultural and economic resource. They are the most popular game species in the United States and the number one driver of conservation funding. On the other hand, they also cause damage to resources including to the agricultural industry, private property and to humans via deer vehicle collisions. Many areas in eastern North America have experienced a decline in white-tailed deer (<i> Odocoileus virginianus </i>) populations over the past twenty years concurrent with changes in landscape, deer harvest strategies, and increasing and expanding black bear (<i> Ursus americanus </i>) and coyote (<i> Canis latrans </i>) populations. Most studies have addressed this problem at small spatial and temporal scales and in areas where predation was assumed to be limiting population growth. We evaluated white-tailed deer fawn recruitment both directly and indirectly at relatively broader spatial and temporal scales. We studied fawn survival on Marine Corps Base Quantico in Virginia, USA from 2008–2019. We used the Kaplan-Meier estimator, and Cox-proportional hazards models to assess annual survival and factors that influence hazard risk such as sex, weather, landscape composition and configuration and food availability. On Marine Corps Base Quantico, we found an increase in red oak mast abundance increases survival and probability of fawn survival was higher during the first interval of the study (2008–2010; 0.71 [0.52–0.96]; survival probability [CI95%]) than the last three intervals (2011–2013; 0.46 [0.30–0.70]; 2014–2016; 0.48 [0.35–0.66] and 2017–2019; 0.50 [0.39–0.63]). We also found that predation was the leading source of mortality. We assessed recruitment using lactation status from hunter harvest data collected by the Virginia Department of Game and Inland Fisheries during a 22-year period in 30 counties in the Appalachian Mountains of western Virginia. We predicted lactation status as a function of landscape composition and configuration, oak mast abundance, weather, age, and predator detection rates using generalized linear mixed models. We found land cover diversity index positively and black bear detection rate negatively influenced recruitment. Age also predicted lactation status with middle-aged females (3.5–4.5 years old) having a higher lactation probability than mature (≥5.5 years old) age and young (2.5 years old) age class deer. Based on these findings, recruitment is likely to be greater in areas that are heterogeneous. Therefore, if an increase in recruitment is desired silvicultural practices such as fire and timber harvest could be used to permanently change land cover types. These silvicultural practices could also be used to increase the number of oaks on the landscape, and augment production of mature oaks as red oak mast abundance influenced fawn survival. Also reducing predation by manipulating predator densities could improve recruitment. Another potential option which needs further research, would be to reduce predator efficiency by increasing hiding cover for fawns. / Master of Science / Deer (<i> Odocoileus </i> spp.) are an important cultural and economic resource. They are the most popular game species in the United States and the number one driver of conservation funding. Conversely, they also cause damage to resources including to the agricultural industry, private property and to humans via deer vehicle collisions. Some areas in eastern North America have experienced a decline in white-tailed deer (<i> Odocoileus virginianus </i>) populations over the past twenty years concurrent with the colonization of coyotes (<i> Canis latrans </i>) as well as changes in habitat. Therefore, we aimed to determine white-tailed deer fawn survival rates and factors affecting recruitment across a large spatial and temporal scale. Recruitment is when an individual becomes part of the reproductive population. However, for harvestable populations, recruitment is when individuals can be legally harvested for the first time. On Marine Corps Base Quantico from 2008–2019, in Virginia, USA we found that probability of fawn survival was higher during the first interval of the study (2008–2010; 0.71 [0.52–0.96]; survival probability [CI95%]) than the last three intervals (2011–2013; 0.46 [0.30–0.70]; 2014–2016; 0.48 [0.35–0.66] and 2017–2019; 0.50 [0.39–0.63]). We also discovered predation was the leading cause of death and probability of survival increased with increasing red oak mast abundance. Over a large spatial (30 counties) and temporal (22 years) scale we examined fawn recruitment by predicting lactation status of female harvested white-tailed deer in the Appalachians Mountains of western Virginia. We found land cover diversity index positively and black bear (<i> Ursus americanus </i>) detection rate negatively influenced recruitment. Age also predicted lactation status with middle-aged females (3.5–4.5 years old) having a higher lactation probability than mature (≥5.5 years old) age and young (2.5 years old) age class deer. Based on these findings, recruitment is likely to be greater in areas that have a mixture of land cover types. Therefore, if an increase in recruitment is desired silvicultural practices such as fire and timber harvest could be used to permanently change land cover types. These silvicultural practices could also be used to increase the number of oaks on the landscape, and augment production of mature oaks as red oak mast abundance influenced fawn survival. Also reducing predation by manipulating predator densities could improve recruitment. Overall, we found diversity of land cover types, food availability, predators, and age influences population dynamics of white-tailed deer.

The island of La Gonave, ~50 km northwest of Port-au-Prince, represents the subsistence Haitian lifestyle. Little is known about human--environment interactions on La Gonave. The first objective of this research was to investigate landscape dynamics through image classification, change detection, and landscape pattern analysis using Landsat 5 (TM) imagery from 1990--2010. Five land cover classes were considered: Agriculture, Forest/Dense Vegetation (DV), Shrub, Barren/Eroded, and Nonforested Wetlands. Overall image classification accuracy was 87%. The area percent change was -39.7, -22.7, 87.4, -7.0, 10.2%, for the respective classes. Landscape pattern analysis illustrated the encroachment of Shrub in core Forest/DV patches and the decline of Agricultural patch integrity. Agricultural abandonment, deforestation, and forest regrowth generated an increasingly fragmented landscape. The second objective of this research was to better understand the survival of the red-tailed hawk (RTH) on La Gonave by exploring the human--RTH relationship. We implemented a survey (n = 121) in 10 rural villages on La Gonave regarding their perceptions and interactions with the RTH during May--June, 2012. During fieldwork we sighted seven RTHs and found one nest. Many respondents noted the aggressive behavior of RTHs during nesting, suggesting reproductive behavior on the island. Our results indicate that RTHs inhabiting this island were not persecuted, despite intense predation of domestic chickens. Aside from predation near homes, villagers do not interact with the hawk as it remains out of sight. The RTH currently has no known predators, but it remains in danger of island extirpation due to ecological degradation. / Master of Science

Nous présentons d’abord une introduction au sujet des marches aléatoires en milieux aléatoires. Nous nous penchons en particulier sur les phénomènes de ralentissement, et plus précisément sur la propriété de vieillissement qu’exhibent plusieurs de ces systèmes lorsque les paramètres sont tels qu’ils conduisent l’environnement aléatoire à produire fréquemment des « pièges », soient des structures qui retiennent la marche aléatoire dans la même région de l’environnement pour de longues durées de temps. Nous illustrons ces notions à l’aide de résultats connus pour deux modèles. Nous présentons par la suite une preuve pour une propriété de vieillissement dans le cas de la marche aléatoire biaisée sur les conductances aléatoires à queues lourdes dans la grille infinie hyper-cubique à d dimensions, qui est le sujet d’un article en attente de publication. / We first present an introduction to the topic of random walks on random environments (RWRE). In particular, we look at slow-down phenomena and, more specifically, ageing properties exhibited by multiple such systems when parameters are chosen such that the random environment frequently produces large “traps”: structures that hold up the progress of the random walk by keeping it in the same region of the environment for long periods of time. We illustrate these behaviours by presenting known results for two such models. We then present a proof for an ageing property in the case of the biased random walk on heavy-tailed random conductances in the infinite hyper-cubic lattice in d dimensions; this is the subject of a research article pending publication.

The long-tailed bat (Chalinolobus tuberculatus) is a threatened species endemic to New Zealand. Historical anecdotes indicate that long-tailed bat populations have declined. However, it is unknown if all populations have declined and if declines are historical or ongoing. Thus, the development and implementation of a national network of long-tailed bat monitoring sites is a priority of the Department of Conservation's Bat Recovery Plan. Potentially, information gained from a national monitoring programme would assist conservation managers to target resources towards those areas where bat populations are declining and provide baseline information to assist managers to gauge the impact of management techniques on bat populations. Of critical importance is that unless it can be demonstrated that long-tailed bat populations have declined and that, that decline is real, management will not be initiated. The aim of this research was to investigate aspects of the ecology of long-tailed bats that would influence the development of a monitoring programme. The distribution, roost selection, habitat use, and activity patterns of a long-tailed bat population that persisted in the Waitakere Ranges, Auckland, were investigated. A study of the Waitakere Ranges long-tailed bat population was significant because (1) the Waitakere Ranges is the northern most location at which long-tailed bats have been researched; (2) the study was the first to be conducted on a long-tailed bat population that persisted in kauri Agathis australis dominated forest remnants; (3) the long-tailed bat population in the Waitakere Ranges is the only known extant population in close proximity to a major urban area; and (4) the factors that are attributed to long-tailed bat population declines (i.e., forest clearance, predation and urbanisation; O'Donnell, 2000) are likely to be ongoing and intensified in the Waitakere Ranges. Twenty roosts were located. Most roosts (85%) were in kauri, 2 were in mature rimu (Dacrydium cupressinum) and 1 was in a kahikatea (Dacrycarpus dacrydioides). All roosts were in large, live, emergent trees. Mean height of roost trees was 38.4 ± 1.3 m and average DBH was 186 ± 12 cm. The entrances of six roost cavities were identified all were located in minor lateral branches in the crown of the tree and were primarily near the tip of branches. Roosts were a mean height of 24.6 ± 3.7 m above ground level. It was argued that roosts in the crowns of kauri were inaccessible to terrestrial mammalian predators. Twenty-eight roost watches were conducted. The average number of bats counted leaving roosts was 10.0 ± 1.5 (maximum = 24). Roosts were occupied by radio-tagged bats for an average of 2.0 ± 0.4 days, and 11 (55 %) were occupied for only one day. Roost size was the lowest reported for long-tailed bats. Roost switching also appeared higher than in other populations that have been studied. It was argued that morepork predation may have a significant impact on the population viability of the population. As in other studies long-tailed bats were found to forage over modified habitats including over farmland, dwellings, orchards and along streams and roads with little vehicular traffic. Long-tailed bats foraged throughout the Waitakere Ranges and their foothills. Bat activity was highly variable. Of the environmental variables analysed, temperature was found to have the greatest influence on bat activity. There were seasonal and habitat influences on bat activity. The relationship between sample sizes, variation in bat detection rates and desired statistical power using automatic bat detectors to monitor populations of bats was explored. A power analysis on activity data collected with automatic bat detectors indicated that declines in bat populations would need to be reflected in declines of greater than fifty percent in bat activity before monitoring programmes would have sufficient power to detect declines in activity. It was recommended that monitoring programmes should concentrate on intensive presence – absence surveys rather than long-term studies at a few sites.

I evaluated effects of 5 intensive pine plantation establishment regimes during years 1 – 5 post-establishment on vegetation communities, loblolly pine (Pinus taeda) growth, nutritional carrying capacity for white-tailed deer (Odocoileus virginianus), habitat values for northern bobwhite (Colinus virginianus), and projected financial viability in the Lower Coastal Plain of Mississippi. Treatments were combinations of mechanical site preparation (MSP), chemical site preparation (CSP), and herbaceous weed control (HWC) designed to reflect the range of operational intensities on industrial forest lands in the southeastern U.S. Results should inform plantation management decisions throughout the region. Pine growth increased with greater treatment intensity. At age 5, trees in the most intensively managed treatment were 1.5 m taller than those in the least intensive treatment. Mechanical site preparation improved growth by alleviating soil physical problems. Growth and yield projections indicated that increased fiber yield may not justify investment in more intensive regimes; financial analysis favored the least expensive treatment, though all regimes produced potential internal rates of return > 9% when managed to financial maturity. Use of MSP with banded HWC yielded abundant low-quality deer forage sufficient for body maintenance; nutritional needs for lactating does were better served by CSP with banded HWC. Broadcast HWC reduced biomass of high-quality forbs. In this region of limited soil nutrients and abundant low-quality forages, the optimal combination of maintenance-level and lactation-level nutrition was provided by CSP or CSP and MSP combined with banded HWC. I evaluated vegetation communities for nesting, loafing, brood-rearing, and fall and winter food suitability for northern bobwhite. No treatment provided brood-rearing habitat due to combined lack of bare ground and forb coverage. Fall and winter feeding, nesting, and loafing cover were best produced by MSP and CSP combined with banded HWC. However, lack of brood-rearing cover may reduce or eliminate usable space in all treatments. Differences between vegetation communities were caused by use of CSP, which eliminated many residual woody and vine species, and by differences in broadcast versus banded HWC. Herbicide use decreased plant diversity and species richness, and impacted successional trajectory. Community differences persisted through year 5.

Thesis (MSc)--University of Stellenbosch, 1982. / ENGLISH ABSTRACT:This study deals with the development of the ethmoidal region of Ascaphus truei Stejneger with special interest to the development of the nasal sacs, the diverticulum medium and the Jacobson's organ. This is to gather more information regarding the phylogeny of the structures. The opinions concerning the phylogenetical migration of the Jacobson's organ, are corroborated by the development of the organ in Ascaphus. The possible origin of the diverticulum medium from the nasal end of the nasolacrimal duct also is commented on. / No Afrikaans abstract available

La Barge à queue noire Limosa limosa est un oiseau limicole communément rencontré tout au long de l’année sur le territoire Français. Les individus présents sur la partie ouest de l’Europe sont représentés par deux sous-espèces : la sous-espèce L. l. limosa, dite barge à queue noire « continentale », est principalement observée pendant les phases de migration et en très faibles effectifs reproducteurs sur les marais ouest Atlantique; la sous-espèce L. l. islandica, dite « islandaise », est quant à elle, exclusivement présente en hivernage le long des côtes atlantiques et de la Manche. L’étude menée au cours de ces travaux de thèse porte principalement sur la barge « islandaise » en dehors de la période de reproduction sur les sites d’hivernage le long de la façade atlantique Française. Contrairement à L. l. limosa, la population de L. l. islandica connaît sur l’ensemble de son aire de répartition, une expansion aussi bien en termes d’effectif qu’en nombre de sites fréquentés. La synthèse des effectifs nationaux hivernants montre que la population hivernante en France suit cette même tendance, avec une progression de 1350 à 27000 individus au cours des vingt dernières années. Actuellement, la France accueille environ 30 % de la population sur un nombre de sites grandissant mais néanmoins restreint, principalement représentés par les Réserves Naturelles littorales abritant des vasières intertidales utilisés comme zone d’alimentation. À partir de données biométriques, génétiques ou encore des historiques de vie des oiseaux équipés de bagues couleurs, les périodes de présence des deux populations sur le territoire Français ont pu être mis à jour. De plus, au sein de la sous-espèce islandaise, plusieurs durées d’hivernage en France ont été avancées, pouvant varier de 2 à 8 mois selon les individus. La phénologie des effectifs étudiée sur chacun des sites suggère une utilisation très variée des sites ainsi que de nombreux échanges entre ces sites au cours d’un même hiver. Couramment utilisée dans la compréhension de la distribution des populations d’oiseaux, la disponibilité de la ressource trophique a également été étudiée au regard du régime alimentaire de la Barge queue noire à partir d’échantillonnages de macrofaune, de collecte de fèces mais aussi d’analyses d’isotopes stables. Au cours de l’hiver, à l’échelle des Pertuis Charentais, les barges montrent deux régimes distincts mais néanmoins monospécifiques. Elles s’alimentent de rhizomes de zostères (Zostera noltii) sur les herbiers des vasières de l’Ile de Ré et de bivalves (Macoma balthica) sur les vasières nues. Au cours de l’hiver, il est supposé que la déplétion de ces ressources conduit à une redistribution des effectifs de barges sur de nouvelles zones d’alimentation voire de nouveaux reposoirs. Les deux régimes alimentaires sont majoritairement retrouvés à l’échelle de la distribution nationale des barges. Néanmoins, leurs distributions au sein des sites français dépend des caractéristiques sédimentaires, des interactions intra et interspécifiques, de la disponibilité de reposoirs de marée haute et des dérangements tels que la chasse. Ce travail a permis d’établir de solides connaissances et aboutit à la collecte de données détaillées et complémentaires qui vont permettre de tester les modèles théoriques de distribution spatiale des organismes à l’échelle d’une région de leur aire de distribution. / The Black-tailed godwit Limosa limosa is a shorebird species commonly observed in France throughout the year. Two sub-species are dissociated in West European. The so called “continental” Godwit L. l. limosa is observed in France during migration cycles and some pairs breed in marshes on the Atlantic coast; the so called “Icelandic” Godwit winters exclusively along coast of the Western Europe. This present work mainly investigates the wintering ecology of Icelandic–godwit in coastal mudflats of France. Contrarily to the continental sub-species, the whole Icelandic-godwit L. l. islandica population increased quantitatively as long as the number of sites used. In France, national counts pointed out that wintering population follows this trend and have increased from 1350 to 27000 individuals during the last twenty years. This population represents now around 30% of the whole islandica population but individuals stage in large flocks in a very limited number of sites, mainly included in Nature Reserves. From standard biometrics, molecular analyses and resighting data, phenologies of the both sub-species can then be specified for France. Furthermore, this study allowed to define how long the wintering period lasts in France for Icelandic-Godwits, between 2 and 8 months depending on individuals. Phenology at site scale suggested that godwits used several sites throughout the winter. As currently used for understanding the distribution of bird populations, trophic resource availability was studied in regard to the diet of the Black-tailed godwit from macrofauna sampling, droppings collection and stable isotope analyses. At the Pertuis Charentais scale, two feeding behaviors were clearly distinguished: seagrass grazing (Zostera notlii) or bivalve probing (Macoma balthica). Food depletion along the winter is expected to lead to the decrease of local populations, and to the selection of new feeding area or roost. Considering the distribution of the species at the national level, the diets were recorded depending on the mudflats’ characteristics. Even if food distribution is commonly used to understand at first the bird population distribution, our observations point out that, here at a local level, more parameters may influence the wintering distribution such as sediment characteristics, intra and inter-specific interactions, high tide roosts availability and human disturbances as the hunt. This work allowed to establish a solid knowledge and to collect many complementary data to test the distribution theories on the Black-tailed Godwit population wintering in France.

Ce mémoire visait à déterminer si un petit parc périurbain, en l’occurrence le Parc national du Mont-Saint-Bruno, est parvenu à maintenir l’intégrité de sa flore au cours des trente dernières années en dépit de pressions humaines croissantes et de perturbations naturelles passées, en plus d’identifier les principaux changements floristiques survenus au cours de cette période et les facteurs responsables. Pour répondre à ces objectifs, une étude historique a été réalisée, en comparant un inventaire floristique ancien (1977) à un inventaire récent (2013). Mes résultats montrent d’abord une forte croissance de la diversité alpha indigène au cours des 35 dernières années, accompagnée d’un déclin significatif de la diversité bêta (30%). Malgré cette homogénéisation taxonomique, la diversité fonctionnelle de la flore forestière s’est accrue, la rendant probablement plus résiliente aux événements perturbateurs. D’autre part, mes analyses ont révélé la progression de traits fonctionnels souvent associés à des habitats forestiers intensément broutés, révélant une certaine influence du cerf de Virginie sur la composition et la structure de la flore forestière. Enfin, mes résultats ont montré que les herbiers botaniques se révèlent être une alternative fiable aux méthodes traditionnelles pour documenter et évaluer l’impact des grands herbivores sur la morphologie des plantes broutées. Au final, cette étude a montré que les petites aires protégées périurbaines peuvent jouer un rôle majeur dans la préservation de la diversité floristique d’habitats forestiers d’intérêt, particulièrement lorsque leur statut de protection permet d’encadrer de manière stricte les activités humaines. / This study aimed to determine whether a small suburban park, namely the Mont-Saint-Bruno National Park, managed to maintain the integrity of its flora over the last thirty years despite increasing human pressures and past natural disturbances, in addition to identify the main floristic changes during this period and the drivers of observed changes. To do so, a historical study was conducted by comparing past (1977) and recent (2013) floristic surveys. First, a striking increase in alpha diversity, driven mostly by native species and associated with a significant decline (30%) in the beta diversity over the last 35 years was found. Despite this taxonomic homogenization, the functional diversity of forest flora has increased, probably increasing its resistance to disruptive events. Furthermore, analyses revealed the progression of functional traits associated with overbrowsed forest habitats, revealing some influence of white-tailed deer on the composition and structure of the forest flora. Finally, my study also showed that herbarium specimens can be used as a reliable alternative to traditional methods to document and assess the impact of large herbivores on browsed plants morphology. In conclusion, this study showed that small suburban protected areas can play a major role in the preservation of the floristic diversity of rich forest habitats, particularly when their status strictly frames human activities.