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Bat conservation has become prevalent over the last few decades due to critical population declines worldwide. Our purpose was to assess whether Brock Fenton's research career coincided with increasing bat conservation research in Canada and North America. Fenton has made significant contributions to bat research during a long and productive publishing career accompanied by participation in research organizations like the North American Society for Bat Research and the Natural Sciences and Engineering Research Council. His conservation research as well as efforts to raise public awareness about these animals has coincided with work for the Committee on the Status of Endangered Wildlife in Canada and its equivalent (Committee on the Status of Species at Risk in Ontario) in ON. To assess the impact of his career, we quantified the relative amount of his peer-reviewed publications with a conservation focus and compared this with the level of conservation-related presentations at annual North American Society for Bat Research conferences. In the same manner, we assessed how often conservation-focused applications were funded by the Ecology and Evolution section of the Natural Sciences and Engineering Research Council-Canada Discovery grant program. Although it cannot be said with authority that Fenton actually initiated the increase in bat conservation research, our results indicate that his research efforts coincide with and presumably had considerable influence in driving this area of research. Key words: Brock Fenton, research, science, impact, career, NASBR, NSERC, Foreword This article appears in a Festschrift of the Canadian Journal of Zoology honouring the contributions of M. Brock Fenton to bat biology. Three decades ago, he authored two papers [...]

We tested the hypothesis that interspecific variation in chiropteran heat tolerance and evaporative cooling capacity is correlated with day-roost microclimates, using three vespertilionid bats that occur sympatrically during summer in Saskatchewan, Canada. We predicted that hoary bats (Lasiurus cinereus (Palisot de Beauvois, 1796); ~22 g) would have higher heat tolerance than little brown bats (Myotis luafugus (Le Conte, 1831); ~7 g) and silver-haired bats (Lasionycteris noctivagans (Le Conte, 1831); ~13 g), as the latter two species roost in tree crevices or cavities that are more thermally buffered than the foliage roosts of hoary bats. We measured core body temperature ([T.sub.b]; passive integrated transponder tags), evaporative water loss, and resting metabolic rate (flow-through respirometry) while exposing individuals to a stepped profile of increasing air temperature ([T.sub.a]) from ~30 [degrees]C in ~2 [degrees]C increments. Experiments were terminated when individuals became hyperthermic ([T.sub.b] [approximately equal to] 42.5 [degrees]C), with maximum [T.sub.a] ([T.sub.a,max]) ranging from 42.0 to 49.7 [degrees]C. As predicted, hoary bats had the highest heat tolerance and evaporative cooling capacity, reaching [T.sub.a,max] ~2.4 and 1.2 [degrees]C higher than little brown and silver-haired bats, respectively. Our results are consistent with the hypothesis that heat tolerance of bats is correlated with roost microclimates, although interspecific variation in body mass and phylogeny may confound these conclusions. Key words: heat tolerance, evaporative cooling capacity, hyperthermia, roost temperature, Myotis luafugus, little brown bat, Lasionycteris noctivagans, silver-haired bat, Lasiurus cinereus, hoary bat, Yinpterochiroptera. Nous avons vérifié l'hypothèse voulant que les variations interspécifiques de la tolérance à la chaleur et de la capacité de refroidissement par évaporation chez les chiroptères soient corrélées aux microclimats des gîtes diurnes, en utilisant trois chauves-souris de la famille des vespertilionidés présentes en sympatrie en été en Saskatchewan (Canada). Nous avions prédit que la tolérance à la chaleur des chauves-souris cendrées (Lasiurus cinereus (Palisot de Beauvois, 1796); ~22 g) serait plus grande que celles des vespertilions bruns (Myotis lucifugus (Le Conte, 1831); ~7 g) et des chauves-souris argentées (Lasionycteris noctivagans (Le Conte, 1831); ~13 g), puisque les gîtes diurnes de ces deux dernières espèces sont des fentes ou cavités dans les arbres caractérisées par des températures moins variables que les gîtes dans le feuillage des chauves-souris cendrées. Nous avons mesuré la température corporelle centrale ([T.sub.b]; radioétiquettes passives intégrées), la perte d'eau par évaporation et le métabolisme au repos (respirométrie dynamique), alors que les spécimens étaient exposés à des températures de l'air ([T.sub.a]) commençant à ~30 [degrees]C et augmentant par incréments de ~2 [degrees]C. Les manipulations cessaient que les spécimens devenaient hyperthermiques ([T.sub.b] [approximately equal to] 42,5 [degrees]C), les Ta maximums ([T.sub.a,max]) allant de 42,0 à 49,7 [degrees]C. Comme prévu, les chauves-souris cendrées présentent la plus forte tolérance à la chaleur et la plus grande capacité de refroidissement par évaporation, atteignant des [T.sub.a,max] de ~2,4 et 1,2 [degrees]C supérieures à celles des vespertilions bruns et des chauves-souris argentées, respectivement. Nos résultats concordent avec l'hypothèse selon laquelle la tolérance à la chaleur des chauves-souris est corrélée aux microclimats des gîtes, bien que des variations interspécifiques de la masse corporelle et la phylogénie puissent nécessiter de nuancer ces conclusions. [Traduit par la Rédaction] Mots-clés : tolerance a la chaleur, capacite de refroidissement par evaporation, hyperthermie, temperature du gite, Myotis lucifugus, vespertilion brun, Lasionycteris noctivagans, chauve-souris argentee, Lasiurus cinereus, chauve-souris cendree, yinpterochiropteres., Introduction Free-ranging endotherms frequently encounter environmental temperatures above their normothermic body temperature ([T.sub.b]), for example, while foraging in sunlit microsites or occupying hot roosts during the day (e.g., Henshaw and [...]