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Understanding microhabitat use is needed to make sound conservation decisions for at-risk, patchy-habitat specialists, such as rock-habitat specialists. Rock habitats offer unique microclimatic refugia for reptiles and mammals. Eastern small-footed bats (Myotis leibii (Audubon and Bachman, 1842)) use rock roosts during the summer, but data on these summer roosts are lacking for this species classified as (critically) imperiled in several US states and Canadian provinces and globally endangered. Our goal was to characterize the structure and microclimate of Myotis leibii roosts at the southwestern periphery of their range. We predicted that Myotis leibii roost temperatures would be warmer and less variable than ambient temperatures and that solitary bats would use horizontal roosts cooler at night, whereas maternity group roosts would be vertical and warmer at night. During summers of 2019 and 2020, we recorded physical (e.g., width) and temperature attributes of 58 Myotis leibii roosts at 16 sites in the Ouachita Mountains. Crevice roosts of Myotis leibii had narrow dimensions like elsewhere in their range and roost temperatures (measured with iButtons) were warmer and more variable than ambient temperatures. Group roosts were larger and had more stable temperatures than solitary roosts. These findings may be useful for assessing population threats, monitoring roost suitability, identifying roost-rich areas that need protection, and even planning artificial roost structures where natural roosts are limited. Key words: Eastern small-footed bat, microhabitat, Myotis leibii, rock roosts, summer roost, temperature, Introduction Species that specialize in habitats with patchy distributions (i.e., habitats that are spatially disjunct on the landscape, such as high elevations, ephemeral pools, rock outcrops) are particularly at risk [...]

Forest bats, including evening bats (Nycticeius humeralis), sometimes roost in manmade structures, such as barns and bridges, but here we report the first observations of evening bats using bird nest boxes for roosting on multiple occasions between 2012 and 2019, a few kilometers north of Jonesboro, Arkansas. Most encounters were in August, when the nesting season is almost finished. We discuss timing and factors that may explain use of bird nest boxes for roosting bv bats., INTRODUCTION During the day bats roost in places that can provide a microclimate suitable for thermoregulation and protection from predators and unfavorable weather conditions (Kunz and Lumsden, 2003). For noncave-obligale [...]

Climate change has advanced the onset of spring and, subsequently, avian nesting activity. Although this advance can have negative consequences such as phenological mismatch, species may be able to increase the annual number of young fledged. Eastern Bluebirds (Sialia sialis) can rear 3 broods to fledging, but in this paper we report 3 pairs that reared 4 broods to apparent fledging in 2016 and 2020 in northeastern Arkansas. Nesting attempts began as early as 18 March with the first laid egg and concluded as late as 18 September with the last fledging event; brood sizes ranged from 2 to 5 chicks. Nests were checked daily 15-18 d post-hatching, increasing confidence in our determination of successful fledging. Unlike a previous report of 4 broods reared by a male that mated with 2 females at once, the pairs at our site all remained together through all 4 attempts. These pairs all consisted of after-second-year birds and we discuss why we believe these nests were successful, as well as factors that allowed these pairs to attempt to rear an additional brood. Received 3 May 2021. Accepted 22 July 2021. Key words: climate change, multi-brooded, nest box, passerine, phenology. Des merlebleus de l'Est (Sialia sialis) élèvent quatre nichées jusqu'à envol apparent dans le nord-est de l'Arkansas Les changements climatiques a avancé le début du printemps et par conséquent celui de la saison de nidification des oiseaux. Bien que cette avancée des dates puisse avoir des conséquences négatives telles qu'une désynchronisation phénologique, les espèces aviaires pourraient être capable d'augmenter le nombre annuel de jeunes à l'envol. Les Merlebleus de l'Est (Sialia sialis) peuvent élever trois couvées jusqu'à l'envol, mais dans cet article, nous présentons trois paires de qui ont apparemment élevé quatre couvées jusqu'à l'envol en 2016 et 2020 dans le nord-est de l'Arkansas. Les tentatives de nidification ont commencé dès le 18 mars avec la ponte du premier oeuf et se sont terminées le 18 septembre au plus tard avec le dernier envol; la taille des nichées variait de deux à cinq poussins. Les nids ont été suivis quotidiennement à partir de 15-18 jours après éclosion, augmentant ainsi le niveau de confiance dans notre détermination de la réussite des envols. Contrairement à un rapport précédent de quatre nichées élevées avec succès par un mâle qui s'est accouplé avec deux femelles à la fois, les couples de notre site sont tous restés ensemble au cours des quatre tentatives. Tous ces couples étaient composés d'individus qui s'étaient déjà reproduit pendant au moins une saison de nidification et nous discutons de ce pour quoi nous pensons que ces nichées ont réussi ainsi que des facteurs qui ont permis à ces couples de tenter d'élever une nichée supplémentaire. Mots-clés: changements climatiques, espèce à plusieurs nichées par an, nichoir, passereau, phénologie., For many passerine species, the number of breeding pairs and nesting attempts are limited by lack of suitable nesting sites and habitat (Cockle et al. 2010, Miller 2010), competition for [...]

Bird-conservation organizations have long promoted the use of predator guards to increase nest success of cavity-nesting birds. Predator guards can effectively reduce nest predation, but lithium grease as a predator deterrent has never been tested. Therefore, our objective was to determine the effectiveness of lithium grease at increasing nest success. In 2017 and 2018, in Jonesboro, AR, we monitored nesting activity by Sialia sialis (Eastern Bluebird) in 148 nest boxes divided evenly among 3 treatments: baffle, grease, and no guard. Our results indicate that grease and baffles equally improved bluebird nest success by about 40%. Overall, lithium grease is a cheap and effective alternative to baffles that owners of bluebird boxes can consider using to increase bluebird nest success. [ABSTRACT FROM AUTHOR]

Changes in temperature and rainfall patterns can have marked impacts on small mammal populations that inhabit environments with highly fluctuating water availability. With projected increases in droughts and fewer but more intense rainfall events in the Southwestern United States, the persistence of many wildlife populations may be threatened. Our goal was to assess how temperature and rainfall during distinct dry and wet seasons influenced the dynamics of a population of big-eared woodrats (Neotoma macrotis) in a mixed oak woodland of coastal central California. We applied Pradel's temporal symmetry models to our 21-year biannual capture–mark–recapture data set (1993–2014) to determine the effects of climatic factors on the woodrats' apparent survival (Φ) and recruitment rate (f). Monthly Φ averaged 0.945 ± 0.001 and varied with season. Monthly f was 0.064 ± 0.001 in the wet season (f was fixed to 0 in the dry season). Monthly population growth rate (λ) varied from 0.996 ± 0.001 during the dry season to 1.001 ± 0.001 during the wet season, which indicated a stable population (0.999 ± 0.001). Total rainfall from the previous season and mean temperature during the same season positively influenced Φ and f. By contrast, Φ and f were negatively influenced by mean temperature from the previous season and total rainfall in the same season. The resulting λ fluctuated with total rainfall, particularly in the wet season. Our results suggest that the big-eared woodrat population may not be substantially affected by warm temperatures per se, potentially because of the microclimate provided by its stick houses. We also discuss its adaptability to local food resources and relatively slow life history relative to other cricetids, and propose that the big-eared woodrat population may be equipped to cope with future climate change. [ABSTRACT FROM AUTHOR]

Despite scientific consensus and educational efforts, approximately 25% of Americans remain unconvinced of anthropogenic climate change (ACC), and significant misconceptions remain. Many studies have assessed adults' views, but it is important to also understand the perceptions of younger individuals who will deal with the future impacts of ACC. In this study, we aimed to determine first-semester college students' attitudes toward and knowledge of ACC, which factors are associated with these measures, and whether knowledge scores differ among audience segments. We issued surveys at 19 American universities and received 2355 responses. The surveys contained sections assessing attitudes, knowledge, and demographics. We analyzed the attitudes and knowledge in ordinal and beta regressions. Most (73.6%) of the students were very concerned about ACC, and their average knowledge scores were high (0.89, standard error = 0.003). Attitude and knowledge were associated with a combination of personal and environmental factors. The concerned students had higher scores, suggesting education may be an important mitigation tool. [ABSTRACT FROM AUTHOR]

The Isles Dernieres Barrier Island Refuge (IDBIR) in Louisiana constitutes a major colonial seabird breeding site but is also considered a high-risk marine area that is susceptible to both natural and anthropogenic disturbances that can be detrimental to breeding areas and food resources. The objective of this study was to track the movements of breeding Royal Terns Thalasseus maximus at the IDBIR to identify important foraging movement parameters and foraging areas. GPS loggers were attached to six Royal Terns during the 2014-2017 breeding seasons. Mean foraging trip distance was 28.8 km and the maximum distance traveled was 47.8 km. The overall mean foraging area (95% fixed kernel densities) was 1042.5 ± 526.1 km2. There was individual variation among foraging area size and foraging habitats that included bays, offshore habitats, and marsh habitats. However, appreciable overlap in foraging areas included marsh habitats ~12 km north of the breeding colony and offshore areas south of the colony. Identifying seabird foraging areas is critical for understanding their resource needs in the Gulf of Mexico, the coast of which is undergoing rapid change, and to assess how major disasters, such as oil spills and hurricanes, may influence important foraging areas. [ABSTRACT FROM AUTHOR]

Several populations of Black Skimmers (Rynchops niger), colonial waterbirds with a tactile foraging strategy, are declining. Improving our limited knowledge of Black Skimmer foraging ecology has become critical to inform conservation decisions. Black Skimmers were GPS-tracked from the Isles Dernieres Barrier Island Refuge in coastal Louisiana, USA, from 27 June-1 July 2013 and 30 May-2 June 2016, to shed light on their foraging movements during the breeding season. Black Skimmers foraged almost exclusively at night, as far as 16 km from the colony in the coastal marshes of Louisiana, in a home range of 86-256 km2. Additional movement data are needed to identify areas of conservation need and provide a basis for future studies of skimmer response to environmental changes. [ABSTRACT FROM AUTHOR]