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Data from: Finer-scale habitat predicts nest survival in grassland birds more than management and landscape: a multi-scale perspective
No full text1. Birds may respond to habitat at multiple scales, ranging from microhabitat structure to landscape composition. North American grassland bird distributions predominantly reside on private lands, and populations have been consistently declining. Many of these lands are enrolled in U.S. federal conservation programmes, and properly guided management policies could alleviate declines. However, more evaluative research is needed on the effects of management policies juxtaposed with other multi-scale habitat features. Furthermore, research focused on nest survival is arguably more valuable because habitat associations with avian densities can sometimes be deceptive. 2. We investigated nest survival of a grassland facultative (red-winged blackbird, Agelaius phoeniceus) an obligate species (dickcissel, Spiza americana), and two nesting communities (ground and above-ground nesters) relative to management and multi-scale habitat (nest-site characteristics, in-field microhabitat, patch metrics, and landscape context). Our study was conducted on private lands in Illinois (2011-2014) and directly linked to policy-based management (disking, herbicidal spraying, spray/interseeding) and landowner decisions. 3. Multi-scale models explained more variation in nest survival compared to single scales or management in three of four analyses (blackbirds, dickcissels, and above-ground nesters). Finer-scale habitat variables, such as nest-site characteristics, were more often in top and among the competitive models relative to landscape factors. 4. Compared with other management types, disking (i.e. tractor-pulled disc harrows removed approximately 50% of vegetation) displayed distinct effects and positively influenced nest survival in above-ground nesters. Also, greater proportions of a field managed cumulatively and yearly, regardless of type, generally improved nest survival for dickcissels and above-ground nesters. All groups except above-ground nesters had generally higher nest survival in native grass fields. 5. Synthesis and applications. Habitat practitioners can improve nest survival for certain grassland birds by directly affecting infield-microhabitat vegetation and structure. However, characteristics associated with specific nest locations often drive nest survival. We suggest habitat managers and agency staff promote native grass practices and management, such as disking, to enhance nest survival of grassland bird populations. Management will likely be most effective in favourable unfragmented grassland landscapes with less surrounding forested areas, which also promote other important responses (e.g. colonization and persistence) of target species
Data from: Common noctules exploit low levels of the aerosphere
No full textAerial habitats present a challenge to find food across a large potential search volume, particularly for insectivorous bats that rely on echolocation calls with limited detection range and may forage at heights over 1000 m. To understand how bats use vertical space, we tracked one to five foraging flights of eight common noctules (Nyctalus noctula). Bats were tracked for their full foraging session (87.27 ± 24 mins) using high-resolution atmospheric pressure radio transmitters that allowed us to calculate height and wingbeat frequency. Bats used diverse flight strategies, but generally flew lower than 40 m, with scouting flights to 100 m and a maximum of 300 m. We found no influence of weather on height and high-altitude ascents were not preceded by an increase in foraging effort. Wingbeat frequency was independent from climbing or descending flight, and bats skipped wingbeats or glided in 10% of all observations. Wingbeat frequency was positively related to capture mass, and wingbeat frequency was positively related to time of night, indicating an effect of load increase over a foraging bout. Overall, individuals used a wide range of airspace including altitudes that put them at increased risk from human-made structures. Further work is needed to test the context of these flight decisions, particularly as individuals migrate throughout Europe
Phenology of Seed and Elaiosome Removal, and Dehiscence
No full textDataset containing observations of fruit dehiscence timing as well as seed and elaiosome removal from seed depots
Black bear home range dataset
No full textHome range data from black bears in MI, MO, and MS (USA) from 2008-2017. Data includes bear ID, range area, state, season, year, and other environmental variables. For details about the variables please refer to the manuscript. If more info needed contact M. Gantchoff
2010 Matrices
No full textData represent abundance matrices with columns representing species or morphospecies of adult beetles found on baits of mature, fresh sporocarps of _Pleurotus ostreatus_ mushrooms. Each entry represents the number of individuals of that beetle species found on a particular bait type (see paper for experimental design of bait arrays). Rows represent individual mushroom baits, with letter codes corresponding to positions in experimental arrays as described in the manuscript. Each tab in the data file represents a different census. Adult beetles were censused mornings and evenings on consecutive days
Data from: Progression of cognitive decline before and after incident stroke
No full textObjective: To determine the trajectory of cognitive decline before and after incident stroke.
Methods: By using data from the English Longitudinal Study of Ageing, we studied 9278 nondemented participants with no history of stroke who underwent cognitive assessment at baseline (wave 1), and at least one other timepoint (waves 2 to 7). We used linear mixed models to analyze repeated measures and longitudinal data.
Results: Among the 9278 participants (56.8% women, mean age 63.1±10.3 years), 471 (5.1%) incident stroke events were identified. Compared with stroke-free participants, multivariable-adjusted rates of prestroke cognitive decline in global cognition, memory, semantic fluency, and temporal orientation of participants who later experienced an incident stroke were increased by −0.029 standard deviation (SD)/year, −0.016 SD/year, −0.022 SD/year, and −0.024 SD/year, respectively. Among the 471 stroke survivors, the multivariable-adjusted acute changes in the four cognitive domains were −0.257 SD, −0.150 SD, −0.121 SD, and −0.272 SD, respectively. In the years following stroke, global cognition declined over time and was steeper than its prestroke slope, i.e. by −0.064 SD/year after multivariable adjustment. The rates of memory, semantic fluency, and temporal orientation decline were −0.046 SD/year, −0.033 SD/year, and −0.037 SD/year, respectively.
Conclusions: Accelerated prestroke and poststroke cognitive decline were associated with incident stroke over a follow-up period of 12 years. Attention should be paid to the long-term cognitive problems of stroke survivors, and intervention and management of major vascular risk factors should start from early- or mid-life to reduce the risk of cerebrovascular disease and the associated cognitive impairment
Data from: Early breeding females experience greater telomere loss
No full textAnnual reproductive success is often highest in individuals that initiate breeding early, yet relatively few individuals start breeding during this apparently optimal time. This suggests that individuals, particularly females who ultimately dictate when offspring are born, incur costs by initiating reproduction early in the season. We hypothesized that increases in the aging rate of somatic cells may be one such cost. Telomeres, the repetitive DNA sequences on the ends of chromosomes, may be good proxies of biological wear and tear as they shorten with age and in response to stress. Using historical data from a long-term study population of dark-eyed juncos (Junco hyemalis), we found that telomere loss between years was greater in earlier breeding females, regardless of chronological age. There was no relationship between telomere loss and the annual number of eggs laid or chicks that reached independence. However, telomere loss was greater when temperatures were cooler, and cooler temperatures generally occur early in the season. This suggests that environmental conditions could be the primary cause of accelerated telomere loss in early breeders
Data from: Ocean warming and acidification may challenge the riverward migration of glass eels
No full textThe dramatic decline of European eel (Anguilla anguilla) populations over recent decades has attracted considerable attention and concern. Furthermore, little is known concerning the sensitivity of eel’s early stages to projected future environmental change. Here we investigated, for the first time, the potential combined effects of ocean warming (OW; ∆ + 4oC; 18oC) and acidification (OA; ∆ - 0.4 pH units) on the survival and migratory behaviour of A. anguilla glass eels, namely their preference towards riverine cues (freshwater and geosmin). Recently arrived individuals were exposed to isolated and combined OW- and OA–conditions for 100 days, adjusting for the salinity gradients associated with upstream migration. A two-choice test was used to investigate migratory activity and shifts in preference towards freshwater environments. While OW decreased survival and increased migratory activity, OA appears to hinder migratory response, reducing the preference for riverine cues. Our results suggest that future conditions could potentially favor an early settlement of glass eels, reducing the proportion of fully-migratory individuals. Further research into the effects of climate change on eel migration and habitat selection is needed to implement efficient conservation plans for this critically endangered species