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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. [ABSTRACT FROM AUTHOR]

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]

Heterotherms vary their use of torpor and choice of refugia to deal with energetic stresses such as reproductive activity and extreme weather. We hypothesized that a temperate-region bat would vary its use of heterothermy in response to air temperature but use of torpor would also be influenced by reproductive stage and roost choice. To test this hypothesis, we collected data on skin temperatures of female Indiana bats (Myotis sodalis) carrying temperature-sensitive radiotransmitters during the summers of 2013–2015. We also measured internal temperatures and external characteristics of roosts used by these bats. We analyzed the influence of daytime air temperature, roost canopy closure, roost type, and bat reproductive stage, on daily heterothermy index and torpor characteristics of 17 bats during 103 full roost days (data collected consistently from when a bat entered its roost in the morning to when it emerged at night). Our data showed that Indiana bat heterothermy was influenced by reproductive stage, roost choice, and weather. Although they used torpor, pregnant bats were the least heterothermic (daily heterothermy index = 3.3 ± 0.6°C SE), followed by juvenile bats (5.6 ± 0.5°C), lactating bats (5.7 ± 0.5°C), and one postlactating bat (13.2 ± 1.6°C). Air temperature also influenced heterothermy of pregnant bats less than bats of other reproductive stages. Thermoregulatory strategies varied on a continuum from use of normothermia in warm roosts to use of long and deep bouts of torpor in cool roosts. The thermoregulatory strategy used seemed to be determined by potential reproductive costs of torpor and energetic consequences of weather. Because Indiana bats used different degrees of heterothermy throughout the summer maternity season, managers should offer maternity colonies an array of refugia to facilitate varying behaviors in response to weather and energetic demands. [ABSTRACT FROM AUTHOR]

Artificial lights may be altering interactions between bats and moth prey. According to the allotonic frequency hypothesis (AFH), eared moths are generally unavailable as prey for syntonic bats (i.e., bats that use echolocation frequencies between 20 and 50 kHz within the hearing range of eared moths) due to the moths' ability to detect syntonic bat echolocation. Syntonic bats therefore feed mainly on beetles, flies, true bugs, and non-eared moths. The AFH is expected to be violated around lights where eared moths are susceptible to exploitation by syntonic bats because moths' evasive strategies become less effective. The hypothesis has been tested to date almost exclusively in areas with permanent lighting, where the effects of lights on bat diets are confounded with other aspects of human habitat alteration. We undertook diet analysis in areas with short-term, localized artificial lighting to isolate the effects of artificial lighting and determine if syntonic and allotonic bats (i.e., bats that use echolocation frequencies outside the hearing range of eared moths) consumed more moths under conditions of artificial lights than in natural darkness. We found that syntonic bats increased their consumption of moth prey under experimentally lit conditions, likely owing to a reduction in the ability of eared moths to evade the bats. Eared moths may increase in diets of generalist syntonic bats foraging around artificial light sources, as opposed to allotonic species and syntonic species with a more specialized diet. [ABSTRACT FROM AUTHOR]

Many birds reduce rest-phase energy demands through heterothermy, physiological responses involving facultative, reversible reductions in metabolic rate and body temperature (T b). Here, we review the phylogenetic distribution and ecological contexts of avian heterothermy. Heterothermy has been reported in 140 species representing 15 orders and 39 families. Recent work supports the view that deep heterothermy is most pronounced in phylogenetically older taxa whereas heterothermy in passerines and other recently diverged taxa is shallower and confined to minimum T b > 20°C. The reasons why deep heterothermy is absent in passerines remain unclear; we speculate an evolutionary trade-off may exist between the capacity to achieve low heterothermic T b and the tolerance of hyperthermic T b. Inter- and intraspecific variation in heterothermy is correlated with factors including foraging ecology (e.g. territoriality and defense of food resources among hummingbirds), food availability and foraging opportunities (e.g. lunar phase predicts torpor use in caprimulgids), and predation risk. Heterothermy also plays a major role before and during migration. Emerging questions include the magnitude of energy savings associated with heterothermy among free-ranging birds, the role phylogenetic variation in the capacity for heterothermy has played in evolutionary radiations into extreme habitats, and how the capacity for heterothermy affects avian vulnerability to rapid anthropogenic climate change. [ABSTRACT FROM AUTHOR]

Variation in weather and food availability impacts the energy budgets of endotherms, with some species using torpor as an energy-saving strategy during periods of negative energy balance. We evaluated how latitudinal differences in energy balance relate to variation in torpor expression and roosting sociality between populations. We monitored summer skin temperatures (Tsk) of individuals from 2 populations of New Zealand lesser shorttailed bats (Mystacina tuberculata) separated by 6° of latitude using temperature telemetry. Although mean summer Ta was only < 1°C lower for the higher-latitude than lower-latitude population, individuals living at the higher-latitude site used torpor on 36% of observation days compared to 11% for lower-latitude bats. None of the recorded weather variables affected the propensity to enter torpor or torpor bout duration; however, the minimum torpid Tsk of bats positively correlated with daily minimum Ta. Roosts occupied by solitary bats were warmer than Ta and temperatures within them fluctuated less than Ta. Higher-latitude individuals roosted solitarily (38%) more frequently than lower-latitude individuals (17%) and individuals from both populations exclusively used torpor while roosting solitarily. Arousals from torpor by higher-latitude bats coincided with sunset and not daily Ta maxima suggesting that bats were not fully exploiting advantages of passive rewarming. Site-specific roost choice and torpor patterns were apparent between M. tuberculata populations during summer, demonstrating that small differences in Ta differentially affect energetic strategy. The thermoregulatory behavior of species inhabiting latitudinal gradients in climate is highly plastic, likely to meet the specific challenges of their environment. [ABSTRACT FROM AUTHOR]

Endotherms allocate large amounts of energy and water to the regulation of a precise body temperature (Tb), but can potentially reduce thermoregulatory costs by allowing Tb to deviate from normothermic levels. Many data on heterothermy at low air temperatures (Ta) exist for caprimulgids, whereas data on thermoregulation at high Ta are largely absent, despite members of this taxon frequently roosting and nesting in sites exposed to high operative temperatures. We investigated thermoregulation in free-ranging rufous-cheeked nightjars Caprimulgus rufigena and freckled nightjars Caprimulgus tristigma in the southern African arid zone. Individuals of both species showed labile Tb fluctuating around a single modal Tb (Tb-mod). Average Tb-mod was 39.7°C for rufous-cheeked nightjars and 39.0°C for freckled nightjars. In both species, diurnal Tb increased with increasing Ta. At Ta ≥ 38°C, rufous-cheeked nightjar mean Tb increased to 42°C, equivalent to 2.3°C above Tb-mod. Under similar conditions, freckled nightjar Tb was on average only 1.1°C above Tb-mod, with a mean Tb of 40.0°C. Freckled nightjars are one of the most heterothermic caprimulgids investigated to date, but our data suggest that during hot conditions this species maintains Tb within a narrow range above Tb-mod, possibly reflecting an evolutionary tradeoff between decreased thermal sensitivity to lower Tb but increased sensitivity to high Tb. These findings reveal how general thermoregulatory patterns at similar Ta can vary even among closely related species. [ABSTRACT FROM AUTHOR]

From 11 to 15 October 2009, we observed Yellow-rumped Warblers (Setophaga coronata coranata) foraging inside an unheated barn on 4 d, and inside a heated modern milking parlor on 2 d at a dairy farm in southeastern Saskatchewan, Canada. Warblers fed on dormant flies that were huddled on the walls inside of the barn and sallied for flies in mid-air and gleaned them from the window screens inside of the milking parlor. These observations were preceded by 2 d of unseasonable cold weather on 9 and 10 October, when maximum temperatures were below 0°C. Yellow-rumped Warblers fed indoors until 15 October after which the days became warmer, and we observed them only outside. Yellow-rumped Warblers most likely entered buildings to feed because unseasonable weather conditions increased their energetic demands and provided incentive for them to exploit shelter and food in novel places. [ABSTRACT FROM AUTHOR]

Oil and natural gas development has increased dramatically in native grasslands over the past 25 years. Some grassland songbirds are less abundant in areas with oil and gas development, but the effects vary among species and geographically within a species' range. The reproductive consequences of nesting in areas with oil and gas development are unknown. We assessed how the density and reproductive success of five species of grassland songbird in Alberta, Canada, varied with distance to oil and gas wells, gravel roads, and trails, and cover of crested wheatgrass (Agropyron cristatum), an aggressive alien plant that often becomes established following anthropogenic disturbance. Crested wheatgrass cover had the greatest impact on the grassland songbird community. Sprague's Pipit (Anthus spragueii) nest survival decreased as the amount of crested wheatgrass increased. As crested wheatgrass cover increased from 0% to 60%, density of Savannah Sparrows (Passerculus sandwichensis) declined by 50%, but they fledged 25% more young from successful nests. Density of Savannah Sparrows was twice as high near wells, and fledging success was 40% higher compared with 700 m away. Distance to gravel roads did not influence the density or reproductive success of any species. Sprague's Pipits and Baird's Sparrows (Ammodramus bairdii) avoided nesting within 100 m of trails, and both species fledged fewer young from successful nests near trails. In contrast, Vesper Sparrows (Pooecetes gramineus) nested close to trails and fledged more young from successful nests near trails. Western Meadowlarks (Sturnella neglecta) were not strongly affected by any variable. Brown-headed Cowbird (Molothrus ater) abundance was three times higher in study plots with wells, although we detected no associated increase in brood parasitism. Our results indicate that the introduction and spread of crested wheatgrass and the creation of access trails to well pads have negative reproductive consequences for primary endemic species such as Sprague's Pipit and Baird's Sparrow, although these results do not extend to other grassland birds. The spread of crested wheatgrass and the disturbance of access trails could be reduced by directional drilling of multiple wells from a single well pad. [ABSTRACT FROM AUTHOR]

Understanding the breeding ecology of grassland birds is vital for understanding the mechanisms underlying their widespread population declines. We describe the breeding biology of Sprague's Pipit ( Anthus spragueii), Vesper Sparrow ( Pooecetes gramineus), Savannah Sparrow ( Passerculus sandwichensis), Baird's Sparrow ( Ammodramus bairdii), and Western Meadowlark ( Sturnella neglecta) and quantify the effects of nest predation, brood parasitism, and weather on the nest survival of these species in southeastern Alberta. Nest predation was the primary cause of nest failure, accounting for 75% of all nest losses. Daily survival rates were higher during incubation than the nestling stage for the three sparrow species, and nest survival of Baird's Sparrows was highest at intermediate temperatures. For all five species, clutch size, hatching success, and fledging success were within the range of values previously reported for these species in other parts of their range. Brown-headed Cowbirds parasitized nests of all species except Sprague's Pipit, with 4-11% of nests containing cowbird eggs. Savannah Sparrow experienced the highest frequency of brood parasitism and was the only species to successfully fledge cowbird young. Parasitized nests of Savannah Sparrows had reduced clutch size and hatching success, and fledged fewer young compared to non-parasitized nests. The overall cost of parasitism to Savannah Sparrows was at least 1.7 young per successful nest. [ABSTRACT FROM AUTHOR]

Bats are among the most heterothermic mammals, with nearly all species investigated under free-ranging conditions to date exhibiting some degree of daily torpor and/or hibernation. We investigated thermoregulation during late winter by seven Nycteris thebaica in a warm, semi-arid habitat in northern South Africa, using temperature-sensitive transmitters to measure skin temperature (T skin). Unexpectedly, we found no evidence for any expression of daily torpor or hibernation based on a total of 86 days of data from 7 bats (one male and six females), despite air temperatures as low as ∼10°C. Instead, daytime T skin was distributed unimodally with most values in the 33–35°C range, and a minimum T skin of 28.4°C at a roost temperature of 24.6°C. There are several possible reasons why N. thebaica may avoid torpor, including predation in roosts, and the long nightly foraging periods of this species compared to many others. [ABSTRACT FROM AUTHOR]

Behavioural plasticity is a critical component of natural selection leading to evolution. However, a surge of studies in the last two decades has discovered a distinct limit to behavioural plasticity, commonly referred to as behaviour types and behavioural syndromes. We set out to understand the relationships across behavioural categories in wild-caught adult, female big brown bats and how they compare between social and solitary behaviours. Using bats sampled from four different maternity colonies, we ran a series of behavioural assays to create a behavioural profile for each individual. The behavioural profile encompassed exploratory, learning, competitive and aggressive categories. We found that Big brown bats exhibit a mean profile relatively unique to other well-documented species, where aggression was linked to increased competitive ability but not to boldness. Our results indicate that the solitary and socially directed behaviours of individuals are not necessarily related and that behaviours pertaining to social interactions are linked most closely to learning abilities. Furthermore, we found evidence that poor body condition may be a predictor of increased social interactions and that behaviours exhibited in the presence of conspecifics are unrelated to those exhibited in solitude. These findings indicate importance of social affiliations on individual behaviours in this species and their uniqueness relative to other well-studied taxa. [ABSTRACT FROM AUTHOR]

Most studies of hibernation physiology sample individuals from populations within a single geographic area, yet some species have large ranges meaning populations likely experience area-specific levels of energetic challenges. As well, few studies have assessed within-season variation. Since physiological adjustments often are influenced by environmental factors, and the types of environments vary with geography, we expected variance in hibernation patterns among geographically separated populations. Our specific goal was to measure intraspecific variation in torpid metabolic rate (TMR) and body temperature ( Tb) as a function of ambient temperature ( Ta) for a non-migratory and migratory species to determine whether there is a continuum in physiological responses based on latitude. We chose big brown ( Eptesicus fuscus) and eastern red bats ( Lasiurus borealis) as model species and sampled individuals from populations throughout each species’ winter range. In both species, individuals from southern populations maintained higher TMR at cooler Tas and lower TMR at warmer Tas than those from northern populations. Big brown bats from southern populations regulated Tb during torpor at higher levels and there was no significant difference in Tb between populations of eastern red bats. Although metabolic responses were similar across the gradient between species, the effect was more dramatic in big brown bats. Our data demonstrate a continuum in thermoregulatory response, ranging from classic hibernation in northern populations to a pattern more akin to daily torpor in southern populations. Our research highlights the potential usefulness of bats as model organisms to address questions about within-species physiological variation in wild populations. [ABSTRACT FROM AUTHOR]

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 take-home 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. [ABSTRACT FROM AUTHOR]

We investigated the influence of lunar and environmental factors on behavior of Common Poorwills (Phalaenoptilus nuttallii) in southern Arizona under a diverse set of natural and artificial conditions. Radio-marked poorwills were most active shortly after sunset during the new moon. Movements declined as evening progressed. Activity remained high for several hours alter sunset when the moon was full. Poorwills were heard calling from March through October, but most calling occurred between early May and September. Only ambient light was correlated with number of poorwills heard calling. More poorwills responded to playbacks of conspecifics when the moon was full than when it was new. Poorwills did not change their response to conspecifics during full moon when playback of poorwill calls followed playback of Great Horned Owl (Bubo virginianus) calls but, during the new moon, fewer birds responded following the owl call. Poorwill behavior is strongly influenced by lunar conditions; their ability to detect and evade predators is important when calling advertises their location. [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 >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. [ABSTRACT FROM AUTHOR]

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 gone 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 ± 6.3° 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 ± 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. [ABSTRACT FROM AUTHOR]

We used radiotelemetry to quantify roost switching and assess associations between members of maternity colonies of forest-dwelling big brown bats. Bats remained loyal to small roosting areas of forest within and between years and switched trees often (X±SD=1.7±0.7 days). For radiotagged bats from the colony in one of these areas, roost-switching frequency was positively correlated with the number of different individuals with which tagged bats shared roosts. We quantified associations between pairs of bats using a pairwise sharing index and found that bats associated more often than predicted when roost and roostmate selection were random but that all tagged bats spent at least some days roosting in different trees, apart from preferred roostmates. Our results suggest that forest-dwelling big brown bats conform to a fission–fusion roosting pattern. Roost switching in forests may reflect the maintenance of long-term social relationships between individuals from a colony that is spread among a number of different trees on a given night. In this fission–fusion scenario, switching between trees, within a local area, could serve to increase the numbers of individuals with which bats maintain associations. We contend that roosting areas in forests are analogous to spatially large roosts in caves, mines and buildings. [Copyright &y& Elsevier]

The use of heterothermy is well documented in the order Caprimulgiformes, but there is conflicting information regarding whether whip-poor-wills are heterothermic. Consequently, we sought to rigorously examine the thermoregulatory abilities of this species. Our study was conducted in southeast South Dakota (42°47′N, 97°0′W), where 35 individuals were captured and outfitted with external, temperature-sensitive radio transmitters. We found evidence that whip-poor-wills used daily torpor during the autumn of 2000 and the spring of 2001 (n = 12 torpor bouts, based on 346 bird-nights of observation). The average minimum skin temperature of two torpid whip-poor- wills (n = 5 torpor bouts) in spring 2001 was n 20.1° ± 2.6°C, and bouts of reduced skin temperature lasted an average of 360.0 ± 93.7 min. The distribution of heterothermy within the Caprimulgiform phylogeny suggests that the trait is ancestral in the order. Specific heterothermic parameters, however, differ among the different species. In particular, the frequency of torpor use in whip-poor-wills is lower than for other species. These data suggest that several factors, including weather conditions and gender-specific reproductive ecology, influence the propensity of whip-poor-wills and other Caprimulgiformes to enter torpor. [ABSTRACT FROM AUTHOR]

Deals with a study which examined the effects of spatially complex habitat or clutter and prey availability on the habitat selection of bats. Materials and methods; Results; Discussion.

Presents a study that examined greater sage-grouse nest and brood habitat use in Alberta using radiotelemetry and assessed the relationship between habitat and population decline. Correlation of vegetation characteristics and the success of nests; Measurements of habitat characteristics; Use of the forward stepwise Discriminant Function Analysis; Suggested wildlife management strategies for sage-grouse.

Several small caprimulgiform birds (<80 g) are known to enter torpor, apparently to cope with a fluctuating supply of insect prey. Since the large Australian tawny frogmouth (Podargus stri-goides; 381--556 g) is also insectivorous, we investigated its ther-moregulatory behaviour and thermal biology to determine whether this species is also heterothermic. In an open woodland at -1,000 m altitude, we equipped eight free-ranging birds with external temperature-sensitive radio transmitters attached to an elastic harness to measure skin temperature (T[subskin] ). Core body temperature (Tb ) was measured in three of these birds fitted with an additional intraperitoneal transmitter. T[subskin] was closely cor-related with Tb , although T[subskin] was usually several degrees below Tb . During the three coldest months of the year (June--August), shallow torpor with Tb as low as 29.1° C occurred frequently, whereas during spring and summer, torpor was not recorded. Torpor occurred either during the night and/or during the first half of the day. Night torpor bouts were initiated after a short activity period around dusk and lasted on average for about 7 h. Torpid birds always aroused before sunrise to either commence a second short foraging period or to fly directly to a day roost tree. After birds roosted, Tb fell again around sunrise, and birds occasionally entered a second dawn torpor bout; however, in most cases, Tb increased rapidly not long after entry, most likely due to passive heating by the sun. We conclude that despite their large body size and energetically conservative hunting strategy, tawny frogmouths, like several related caprimulgiform species, frequently enter shallow torpor when low Ta demands high en-ergetic costs for normothermic thermoregulation and likely reduces insect availability. [ABSTRACT FROM AUTHOR]

Presents a study which examined the productivity and nesting activities of greater sage-grouse in southeastern Alberta using radio-telemetry. Cause of the decline in sage-grouse populations; Methods used; Results; Discussion.

Presents a study that investigates the year-to-year reuse of roost trees by California bats in Southern British Columbia. Factors that drive researchers to study the roosting behavior of bats; Methodology used in the study; Findings on the roost trees used by bats.

Discusses a study which assessed the use of torpor by free-ranging Australian owlet-nightjars. Period of the year when torpor bouts occurred; Lowest skin temperature recorded for any bird that entered torpor; Duration of torpor bouts.

Provides information on an experiment that tested the effect of small-scale disturbances and an access road in a forest setting on habitat use by bats. Study area and methods; Forest harvesting as a form of habitat disturbance; Increase in bat activity after forest harvesting.

Presents information on a study which investigated the effects of moonlight on the activity of bats. Effects of biological rhythms and illumination on nocturnal mammals; Materials and methods; Results of the study.

Presents a study which indicated that although most commonly found roosting in buildings, big brown rats have been found roosting in natural hollows of beech, kurta, ponderosa pine, brigham and western redcedar as well as rock crevices. Details on the most important resource for bat species; Methodology used to determine the width of bats and cavity entrances; Results of the study.

Reports that insectivorous bats use echolocation to make detailed discriminations among targets under controlled laboratory conditions. Testing of the ability of bats to distinguish edible and inedible targets; Comparison of response to moving and stationary prey; Distinguishing of size of prey.

Determines if general ecological relationship can be inferred from simple morphological measurements of foraging common nighthawks. Principal measurement used in the study to calculate power and speed relationship; Mechanical errors associated in using a stopwatch; Importance of the method used in measuring the flight speed of birds.

Presents a study which assessed the roost-site preferences of forest-dwelling California bats (Myotis californicus). Comparison of the characteristics of trees and sites of roost trees; Efforts to determine whether the features of tree roost selected by a variety of bats are similar; Information on the implications.

Clutch reduction (the disappearance of 1 or more eggs) is often reported in studies examining avian reproductive success and has typically been attributed to nest predation. We recorded clutch reductions at 20 (11%) of 188 Piping Plover (Charadrius melodus) nests at Chaplin Lake, Saskatchewan from 2002 to 2004. Partial clutch reductions were initially assumed to be the result of predation. However, all egg disappearances at three nests we monitored using video cameras were due to accidental removal by incubating parents. Our observations suggest that accidental removal may occur more frequently than expected in alkaline environments, and are likely misclassified as losses due to predation. Received 10 December 2007. Accepted 1 July 2008. [ABSTRACT FROM AUTHOR]

The authors highlights some of the significant events in the 90-year history of the "Canadian Journal of Zoology" (CJZ), including the first issue of CJZ with the original name of the "Canadian Journal of Research" in May 1929, a system of peer review established by editor William Hoar in 1964, and the affiliation of CJZ with the Canadian Society of Zoologists since its inception.

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 lucifugus (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 (Tb; 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 (Ta) from ∼30 °C in ∼2 °C increments. Experiments were terminated when individuals became hyperthermic (Tb ≈ 42.5 °C), with maximum Ta (Ta,max) ranging from 42.0 to 49.7 °C. As predicted, hoary bats had the highest heat tolerance and evaporative cooling capacity, reaching Ta,max ∼2.4 and 1.2 °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. [ABSTRACT FROM AUTHOR]

Standardized monitoring is critical for conservation because reliable survey data are used to inform the necessity, type, and effectiveness of conservation actions. Many of the avian monitoring data used for conservation are collected by "comprehensive" programs that survey for all species observed; however, there are some species that have low availability for detection during comprehensive surveys and are instead monitored with targeted programs. Unfortunately, those targeted programs are rarely evaluated relative to existing programs and management objectives to inform allocation of effort. We assessed the statistical performance of the comprehensive North American Breeding Bird Survey (BBS), the targeted Canadian Nightjar Survey (CNS), and the two programs combined for the Common Nighthawk (Chordeiles minor). First, we used parameters from the existing datasets to simulate population declines and determined the probability of detecting those declines. Analyses that combined both datasets resulted in higher probability of detecting a 30% population decline (BBS: 38%, CNS: 64%, combined: 69%). Next, we built probability of occurrence models and assessed the predictive performance of those models. Combined analyses had similar predictive performance to the CNS and moderated poor performance of the BBS in the north (mean Cohen's kappa; BBS: 0.40, CNS: 0.46, combined: 0.50). Our results suggest that data from targeted monitoring is important for evaluation of Common Nighthawk population trend and habitat relationships but is best combined with BBS data. Comprehensive and targeted monitoring programs may be better when considered together, and exploration of data combination should become the rule, not the exception. We suggest that the framework we present can be used as a starting point for evaluating targeted monitoring programs relative to defined objectives and existing programs, with the potential to explore hypothetical management scenarios. [ABSTRACT FROM AUTHOR]

The article presents an editorial on the ongoing research work and publications in the field of echolocation in bats. Topics discussed include a brief of the second international symposium on bat echolocation research, a brief about the research publication papers on this field, and researched data on bat echolocation.

Birds in the family Caprimulgidae generally exhibit high nest site fidelity, but it is not known if fidelity extends to foraging sites, especially for Common Nighthawks (Chordeiles minor), which are otherwise one of the most studied species. Common Nighthawks are ecologically distinct from other caprimulgids, being one of the few true aerial hawking species and among the longest distance migrants in the group. We predicted these birds would exhibit fidelity between years to a foraging site in British Columbia, Canada, where they forage in large numbers on a nightly basis and the same individuals return nightly. We banded individuals and, for a subset of birds, attached transmitters programmed to activate upon return to the foraging area the next year. We estimate we marked approximately 10% of the birds foraging at the site, but did not recapture a single marked bird despite capturing potentially 50% of birds foraging at that site over the two subsequent years. Furthermore, we did not detect any of the subset of birds with radiotransmitters, indicating they did not return to the foraging site in the year following initial capture. Our data suggest low fidelity between years to a foraging site, in contrast with the published records for nesting by this species and with the general expectations for the group. [ABSTRACT FROM AUTHOR]

Vast areas of North American grasslands have been lost and degraded, resulting in unprecedented declines of biodiversity. For example, 82% of North American grassland songbird species are experiencing population declines. Basic natural history, life history, and demographic data from different regions and time periods are essential for modeling population dynamics and developing effective conservation strategies for grassland birds. We monitored 392 nests to provide information on nesting biology, quantify reproductive success, and gain insight into the extent to which predation and weather influence nest survival of 7 grassland songbird species in southwest Saskatchewan, during 2010 and 2011. Clutch sizes of all species were within the range reported previously and declined as the breeding season progressed, particularly for Chestnut-collared Longspur (Calcarius ornatus), Vesper (Pooecetes gramineus) and Baird's (Centronyx bairdii) sparrows, and Western Meadowlark (Sturnella neglecta). Overall, 32–69% of the nests we monitored were depredated, and predation accounted for 91% of all unsuccessful nesting attempts. Daily survival rates were lowest during the nestling stage for 5 species, and nest survival estimates ranged from 16% to 48%. Nest survival of 4 species was influenced by the temporal effects of age and date. Chestnut-collared Longspur and Western Meadowlark nest survival increased through early to mid-incubation and declined thereafter until ∼3 d prior to fledging before increasing again. Nest survival of these 2 species, along with Sprague's Pipit (Anthus spragueii) and Vesper Sparrow, were lowest in late June to early July. We found no support for a strong effect of precipitation on nest survival. However, nest survival rates declined with increasing ambient temperature for Chestnut-collared Longspur and Horned Lark (Eremophila alpestris), the 2 study species with the most exposed nests, and were highest for Western Meadowlark nests when ambient temperatures were between 15 and 24 °C. [ABSTRACT FROM AUTHOR]

Compared to mammals, there are relatively few studies examining heterothermy in birds. In 13 bird families known to contain heterothermic species, the common poorwill (Phalaenoptilus nuttallii) is the only species that ostensibly hibernates. We used temperature-sensitive radio-transmitters to collect roost and skin temperature (Tskin) data, and winter roost preferences for free-ranging poorwills in southern Arizona. Further, to determine the effect of passive rewarming on torpor bout duration and active rewarming (i.e., the use of metabolic heat to increase Tskin), we experimentally shaded seven birds during winter to prevent them from passively rewarming via solar radiation. Poorwills selected winter roosts that were open to the south or southwest, facilitating passive solar warming in the late afternoon. Shaded birds actively rewarmed following at least 3 days of continuous torpor. Average torpor bout duration by shaded birds was 122 h and ranged from 91 to 164 h. Active rewarming by shaded birds occurred on significantly warmer days than those when poorwills remained torpid. One shaded bird remained inactive for 45 days, during which it spontaneously rewarmed actively on eight occasions. Our findings show that during winter poorwills exhibit physiological patterns and active rewarming similar to hibernating mammals. [ABSTRACT FROM AUTHOR]

The article presents a response to a review of the book "Tawny Frogmouth," by G. Kaplan by S. Pruett-Jones. The argument raised by Pruett-Jones that the book is an example of a good natural history text is criticized by the author. Several dubious claims made in the book are also cited, including the suggestion that seabird nostrils filter out salt.

Prewinter fat accumulation along with the use of shallow torpor permits the survival of free-ranging Australian Tawny Frogmouths ( Podargus strigoides) during winter, when prey availability is low and metabolic costs to maintain high body temperatures increase. Captive studies of these animals currently provide no direct support for this ability. We investigated mass fluctuations of 18 captive birds over 8 years at a North American zoo facility to determine whether or not body mass gains were correlated with seasonality, and subsequently provide indirect evidence for regular torpor use. We found that mass fluctuations were correlated with season, as predicted. The lowest body masses occurred during summer, and the greatest mass occurred during late fall and early winter, based on the seasons of the Northern Hemisphere. We conclude that body fat accumulation by captive Tawny Frogmouths occurs in preparation for winter when, under natural conditions, they regularly use torpor, and that Tawny Frogmouths are capable of altering physiological processes to match the environments in which they live, no matter their Southern Hemisphere origins. [ABSTRACT FROM AUTHOR]

Grassland birds have undergone widespread global population declines due to loss and degradation of native grasslands. Activities associated with non-renewable energy derived from oil and natural gas extraction have substantially increased on grasslands. The cumulative disturbance generated by natural gas development creates a network of non-linear (e.g., bare ground and exotic plant species) and linear (e.g., roads, trails, pipelines) features that may degrade habitat quality for grassland species. We quantified grassland songbird abundance in two areas of southwestern Saskatchewan, Canada, to determine whether variation in abundance 1) depended on the type and amount of disturbance at two spatial extents, and 2) was more affected by the cumulative impacts of natural gas development than any single type of disturbance. We found that specific types of disturbances impacted the abundance of most species to varying degrees. The cover of different types of linear disturbance had the strongest effect on the most species. Natural gas disturbance within 450 m of point counts was more influential than disturbance within 200 m for nearly all species in both areas. Only Savannah sparrow (Passerculus sandwichensis) abundance was most strongly influenced by the cumulative amount of disturbance with abundance decreasing with increased disturbance. Overall, we detected few consistent patterns among species, or within species between our two study areas. Our results indicated that the impact of natural gas infrastructure can extend beyond the local influences associated with well sites and that relatively small amounts of disturbance (<2%) may impact grassland songbird abundance. We recommend that researchers use caution when studying well-density effects or combining individual types of disturbance without understanding the separate effects each type of disturbance has on the species or community of interest. Not doing so may lead to investing resources into management practices that do not have the greatest possible benefit for grassland songbirds. [ABSTRACT FROM AUTHOR]