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This paper is based on an oral presentation delivered at the 89th Annual Meeting of the American Society of Mammalogists in Fairbanks, Alaska on 25 June 2009, where I was honored to receive the Society's Joseph Grinnell Award for excellence in education in mammalogy. The motivation for the topic of my presentation was the many 'bad' talks all of us have endured at scientific meetings and in other situations. As I do for undergraduate and graduate classes, rather than providing a list of seminar 'dos' and 'don'ts,' I presented a practical demonstration of many of the 'don'ts' I have observed and then attempted to present the same information incorporating as many of the 'do's' as I could. In other words, I delivered a bad and then a good version of the same presentation. My goal was to provide the audience with advice that would be useful when presenting information about mammals to scientific colleagues and the general public (e.g., service clubs or school groups). Given that it is impossible to recreate aspects of my performance using the written word, my purpose here is to summarize my opinions about the key elements of good talks. The goal of a talk should be to maximize the likelihood that it will be perceived as interesting, thoughtful, and purposeful and that the key takehome message(s) will be understood and remembered. It is my strongly held belief, especially with the now essentially universal use of computer slideware (e.g., PowerPoint), that an opportunity exists to enhance the usefulness of oral presentations but a real risk of muddling them to the point where the intended message is lost. I also make some recommendations about how to avoid common pitfalls of using this software. DOI: 10.1644/09-MAMM-A-271.1. Key words: Grinnell Award, how to, opinion, oral talks, presentations

Understanding the functional significance of bird sounds can provide valuable insight into the behavior and how birds use habitat. We show that the Common Nighthawk (Chordeiles minor) wing-boom display is a territorial signal associated with the nest location that can be used to identify territorial habitat use. In other words, the Common Nighthawk wing-boom display can be considered analogous to song due to its potential function in territoriality. We captured, tagged, and tracked 21 male Common Nighthawks in northeastern Alberta to confirm the functional significance of the wing-boom display and describe Common Nighthawk territoriality. Mean wing-boom use density (hereafter “area”) size was 10.2 ha (SD = 11.7 ha). We found minimal overlap in the wing-boom area (5 of 15 neighboring male pairs, 0.2–4.5% overlap), suggesting the wing-boom display represents an exclusive territory. Comparison of wing-boom locations and random points within the wing-boom area confirmed that male Common Nighthawks select areas near the nest to perform wing-boom displays. There was high wing-boom area overlap for the same individual between years. Differences between years reflected shifts in nest location, suggesting that the wing-boom display is a good indicator of the nest location and territory. Future Common Nighthawk surveys should record the type of acoustic signal observed to differentiate territorial habitat use from other functions. Many taxa that produce non-vocal sounds as part of breeding displays could similarly benefit from a functional understanding to provide insight into habitat use. [ABSTRACT FROM AUTHOR]

Little Brown Myotis (Myotis lucifugus) is one of the most common and widely distributed mammals in Canada and has been recorded to live over 30 years in the wild. As part of a long-term bat research project in Cypress Hills Interprovincial Park, Saskatchewan, we recaptured a male Little Brown Bat in a mist net over Battle Creek on 12 June 2021. The bat was recaptured within 100 m of where it was first captured and banded as an adult in 1993, indicating that this bat was at least 29 years old and exhibited repeated use of the same summer flying, foraging, and drinking site. The bat was not caught in the intervening years; therefore, its frequency of use of this site is unknown. In eastern North America, this species has declined because of high mortality rates associated with White-nose Syndrome (WNS). WNS has been moving westward and has now been detected in eastern and western Saskatchewan. Understanding aspects of the natural history of Little Brown Bat, including longevity, is important before WNS is detected in a region and leads us to advocate continued marking of individuals (e.g., banding, PIT tagging) to continue learning about bat longevity and survival before and after WNS infection. [ABSTRACT FROM AUTHOR]

Much of our current understanding of the demographic effects of habitat fragmentation on bird populations is derived from studies of passerines in forests and tallgrass prairie surrounded by woody vegetation. We quantified grassland bird density, nest survival, and productivity in 41 native mixed-grass prairie pastures during 1997-2000 in southern Saskatchewan, Canada. Pastures ranged in size from 18 ha to 11,600 ha and were typically surrounded by agriculture (i.e., ranching and annual cropping). Grassland passerines did not respond strongly or uniformly to patch size. Sprague's Pipit (Anthus spragueii) was the only species whose density increased with pasture size. Patch size had minimal influence on nest survival of Sprague's Pipit or Clay-colored Sparrow (Spizella pallida); whereas nest survival increased with patch size for Savannah Sparrow (Passerculus sandwichensis) and declined for Baird's Sparrow (Ammodramus bairdii), Chestnut-collared Longspur (Calcarius ornatus), and Western Meadowlark (Sturnella neglecta). Time-specific factors (i.e., nest age, date, and year) were more important predictors of nest survival than patch size. Exploratory analyses indicated that effects of edge distance, pasture shape, or landscape on nest survival were just as likely as patch-size effects. However, effects of edge on Chestnut-collared Longspurs may be governed by landscape-level factors, because nest survival decreased with distance to edge in landscapes with increased amounts of cropland. Our results indicate that mixed-grass prairie parcels [greater than or equal to] 18 ha play a role in the conservation of several grassland passerine species currently in decline, but the conservation of Sprague's Pipit likely depends on maintaining larger tracts of native prairie. Key words: edge distance, fragmentation, grassland birds, nest survival, patchsize effects. La majeure partie de notre comprehension actuelle des effets demographiques de la fragmentation de l'habitat sur les populations d'oiseaux provient des etudes sur les passereaux dans les forets et les prairies d'herbes hautes entourees de vegetation ligneuse. Nous avons quantifie la densite en oiseaux de prairie, la survie des couvees et la productivite dans 41 paturages de type prairie herbacee indigene en 1997-2000 dans le sud de la Saskatchewan, Canada. Les paturages avaient une taille qui variait de 18 a 11 600 ha et ils etaient generalement entoures par des activites agricoles (i.e. elevage et cultures annuelles). Les passereaux repondaient faiblement et de maniere non uniforme a la taille des parcelles d'habitats. Anthus spragueii a ete la seule espece dont la densite augmentait avec la taille des prairies. La taille des parcelles avait une influence minimale sur la survie des couvees d'Anthus spragueii et de Spizella pallida, alors que la survie des couvees augmentait avec la taille des parcelles pour Passerculus sandwichensis et declinait chez Ammodramus bairdii, Calcarius ornatus et Sturnella neglecta. Les facteurs temporelles (i.e. l'age, la date et l'annee de la couv6e) etaient des predicateurs plus importants de la survie des couvees que la taille des parcelles. Des analyses exploratoires ont indique que les effets sur la survie des couvees de la distance la bordure, de la forme des paturages et du paysage etaient aussi peu probables que les effets de taille des parcelles. Neanmoins, les effets de bordure sur Calcarius ornatus pourraient etre issus de facteurs qui agissent a l'echelle du paysage, puisque la survie des couvees diminuait avec la distance a la bordure dans les paysages avec des quantites croissantes de cultures. Nos resultats indiquent que les parcelles de 18 ha de prairies herbacees jouent un role important dans la conservation de plusieurs especes de passereaux de prairie actuellement en declin. Mais, la conservation d'Anthus spragueii depend probablement du maintien de plus larges etendues de prairies indigenes.

Previous studies of forest-dwelling bats have identified physical features of trees and forests that correlate with the presence of bats by comparing roost sites to paired, randomly selected sites. This method may be limited if the absence of bats from random sites cannot be confirmed. Our purpose was to address roosting ecology of female big brown bats (Eptesicus fuscus) using a different approach. We quantified relative use of trees with 3 different types of cavity openings (long crevices, multiple holes, or single holes) and compared the relative use of these potential roosts to the availability of each roost type in the study area. Bats used trees with multiple holes and crevices significantly more often than expected based on their availability and trees with single holes less often than expected. Crevice roosts had significantly larger cavities than did single holes and roosting-group size was positively correlated with cavity volume. No relationship was found between cavity volume and tree height or stem diameter of roost trees, 2 variables that have been reported to correlate with roost selection in other studies of forest bats. Examination of our data suggests that the volume of roost cavities may be an important selection criterion for colonial, forest-living bats and that standard interpretations of the roost versus random-tree approach may not accurately identify patterns of roost selection in some systems. Key words: cavity volume, Chiroptera, forests, radiotelemetry, roosting ecology, tree cavities

Most recent research on the roosting habits of temperate, forest-living bats has focused on species that use enclosed cavities, but less has been done to address roosting by foliage-living species, which are assumed to have more flexible roost requirements. Numerous studies have suggested that bats select roosts on the basis of microclimate, yet few have tested this hypothesis empirically and none have addressed the use of foliage roosts in this context. We used radiotelemetry to locate roost sites of reproductive female hoary bats (Lasiurus cinereus) then compared a variety of physical features of these trees with randomly selected nonroost trees. We also recorded ambient temperature and wind speed at roost and nonroost sites to test the hypothesis that physical features associated with foliage roosts provide energetic benefits. Hoary bats selected roost sites on the southeast side of mature white spruce trees (Picea glauca; X orientation 158.6 [+ or -] 6.3[degrees] SSE). Roost trees were more likely than random trees to be the same height as the surrounding forest canopy; had less canopy cover facing out from the tree in the direction of the roost branch; and had lower forest density on their southeast side. Wind speed was significantly lower at roosts sites compared with opposite sides of the same trees, presumably due to increased protection from prevailing west winds. Incorporating an estimate of convective cooling due to wind, we predicted daily thermal energy expenditure for normothermic bats and found that selected roost sites provided statistically significant energy savings (up to 1.60 [+ or -] 0.99 kJ/day) relative to the predicted expenditures if bats had roosted on the opposite sides of trees. Our results provide direct evidence that hoary bats select forest roosts on the basis of microclimate and suggest that roost requirements of foliage-roosting species may be more specific than has been previously assumed. Key words: AIC, Chiroptera, convective cooling, foliage, forest, hoary bats, Lasiurus cinereus, roosting