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Predictive analytics monitoring, the use of patient data to provide continuous risk estimation of deterioration, is a promising new application of big data analytical techniques to the care of individual patients. We tested the hypothesis that continuous display of novel electronic risk visualization of respiratory and cardiovascular events would impact intensive care unit (ICU) patient outcomes. In an adult tertiary care surgical trauma ICU, we displayed risk estimation visualizations on a large monitor, but in the medical ICU in the same institution we did not. The risk estimates were based solely on analysis of continuous cardiorespiratory monitoring. We examined 4275 individual patient records within a 7 month time period preceding and following data display. We determined cases of septic shock, emergency intubation, hemorrhage, and death to compare rates per patient care pre-and post-implementation. Following implementation, the incidence of septic shock fell by half (p < 0.01 in a multivariate model that included age and APACHE) in the surgical trauma ICU, where the data were continuously on display, but by only 10% (p = NS) in the control Medical ICU. There were no significant changes in the other outcomes. Display of a predictive analytics monitor based on continuous cardiorespiratory monitoring was followed by a reduction in the rate of septic shock, even when controlling for age and APACHE score.

The Lower Keys marsh rabbit ( Sylvilagus palustris hefneri ) is one of many endangered endemic species of the Florida Keys. The main threats are habitat loss and fragmentation from sea-level rise, development, and habitat succession. Exotic predators such as free-ranging domestic cats ( Felis catus ) pose an additional threat to these endangered small mammals. Management strategies have focused on habitat restoration and exotic predator control. However, the effectiveness of predator removal and the effects of anthropogenic habitat modifications and restoration have not been evaluated. Between 2013 and 2015, we used camera traps to survey marsh rabbits and free-ranging cats at 84 sites in the National Key Deer Refuge, Big Pine Key, Florida, USA. We used dynamic occupancy models to determine factors associated with marsh rabbit occurrence, colonization, extinction, and the co-occurrence of marsh rabbits and cats during a period of predator removal. Rabbit occurrence was positively related to freshwater habitat and patch size, but was negatively related to the number of individual cats detected at each site. Furthermore, marsh rabbit colonization was negatively associated with relative increases in the number of individual cats at each site between survey years. Cat occurrence was negatively associated with increasing distance from human developments. The probability of cat site extinction was positively related to a 2-year trapping effort, indicating that predator removal reduced the cat population. Dynamic co-occurrence models suggested that cats and marsh rabbits co-occur less frequently than expected under random conditions, whereas co-detections were site and survey-specific. Rabbit site extinction and colonization were not strongly conditional on cat presence, but corresponded with a negative association. Our results suggest that while rabbits can colonize and persist at sites where cats occur, it is the number of individual cats at a site that more strongly influences rabbit occupancy and colonization. These findings indicate that continued predator management would likely benefit endangered small mammals as they recolonize restored habitats.

Knowing what the highest-level mammalian carnivores and intermediate levels eat throughout the geography and how human activities may affect their community dynamics is relevant information to focusing and deciding on conservation efforts within a territory. In this review, we characterize geographically the accumulated knowledge about the trophic niche of terrestrial mammalian carnivore species and evaluate the spatial relationship between the species richness distribution and the geographical distribution of their trophic knowledge in Chile. We found 88 peer-reviewed papers that include trophic studies per se, theses, and short notes carried out in Chile, where at least one trophic element was reported for terrestrial mammalian carnivore species. We found a positive relationship between the species richness distribution pattern and the spatial distribution of accumulated trophic knowledge, i.e., most of the papers have been conducted in Central-southern Chile (Central Chile and Temperate Forest ecoregions) responding to the highest co-occurrence of carnivore species within the limits of the biodiversity hotspot, the most threatened area in the country. Despite this general relationship, we recognize gaps in knowledge regarding regions of the country that require more research effort, such as O'Higgins, Maule, and Ñuble regions, as well as focus efforts on certain species with no or almost no knowledge of their trophic ecology, such as Leopardus colocola, Lyncodon patagonicus and Conepatus chinga. Except for the northern Chilean ecosystems, there is a generalized report of high consumption of exotic mammals in the diet of carnivores in the center and south of the country. However, of the 98 localities recognized in the 88 papers, 20.4% correspond to an anthropized environment, while most (79.6%) correspond to a "non-anthropized" environment or protected area. We hope this review allows researchers and decision-makers to consider the knowledge and lack thereof of carnivore trophic interactions as an opportunity to conserve entire natural communities throughout the Chilean territory. [ABSTRACT FROM AUTHOR]

Atlantic ghost crabs (Ocypode quadrata) are predators of beach-nesting shorebird nests and chicks on the United States' Atlantic and Gulf coasts. Ghost crabs may also disturb birds, altering foraging, habitat use, or nest and brood attendance patterns. Shorebird conservation strategies often involve predator and disturbance management to improve reproductive success, but efforts rarely target ghost crabs. Despite the threat to shorebird reproductive success, ghost crabs are a poorly understood part of the beach ecosystem and additional knowledge about ghost crab habitat selection is needed to inform shorebird conservation. We monitored ghost crab activity, defined as burrow abundance, throughout the shorebird breeding season on Metompkin Island, Virginia, an important breeding site for piping plovers (Charadrius melodus) and American oystercatchers (Haematopus palliatus). We counted burrows at shorebird nests and random locations throughout the breeding season and investigated whether ghost crab activity was greater at nest sites relative to random locations without shorebird nests. While we observed burrows at all nest sites (n = 63 nests), we found that burrow counts were lower at piping plover nests with shell cover, relative to random locations with no shell cover. Ghost crabs may avoid piping plover nest sites due to anti-predator behaviors from incubating adults or differences in microhabitat characteristics selected by piping plovers. We also investigated the effects of habitat type, date, and air temperature on the abundance of ghost crab burrows. We found that while crab burrows were present across the barrier island landscape, there were more burrows in sandy, undisturbed habitats behind the dunes, relative to wave-disturbed beach. Additionally, ghost crab activity increased later in the shorebird breeding season. Understanding when and where ghost crabs are most likely to be active in the landscape can aid decision-making to benefit imperiled shorebird populations. [ABSTRACT FROM AUTHOR]

Endangered species recovery requires knowledge of species abundance, distribution, habitat preferences, and threats. Endangered beach mouse populations (Peromyscus polionotus subspp.) occur on barrier islands in Florida and Alabama. Camera traps may supplement current methods and strengthen inferences of animal activity. Between November 2020-February 2022, we conducted 140 camera surveys across 86 track tubes on Tyndall Air Force Base, Florida. We used generalized linear models to explore the relationships between beach mouse detections and environmental factors. We detected beach mice on 6,397 occasions across all tubes. Detections ranged from 0 to 147 observations/survey. Our top model suggested that beach mouse detection was related to cover type with positive associations with grassland and dune compared to scrub. Detections further varied depending on islands, were negatively associated with predator detections, and increased in winter months. Our results suggest that cameras can supplement inference about vegetation associations at broader scales to complement monthly track tube surveys since detection counts are more informative than presence/absence data alone. Given that all tubes exhibited at least one observation, the camera trap network may provide a less frequent and more robust survey method relative to monthly track tube surveys. Adopting such a multifaceted approach may reduce effort and strengthen inference to inform recovery objectives and adaptive management range-wide for all listed beach mouse subspecies. [ABSTRACT FROM AUTHOR]

Mercury contamination in wildlife has rarely been studied in the Southern Appalachians despite high deposition rates in the region. From 2006 to 2008 we sampled feathers from 458 birds representing 32 species in the Southern Appalachians for total mercury and stable isotope δ (15)N. Mercury concentrations (mean ± SE) averaged 0.46 ± 0.02 μg g(-1) (range 0.01-3.74 μg g(-1)). Twelve of 32 species had individuals (7 % of all birds sampled) with mercury concentrations higher than 1 μg g(-1). Mercury concentrations were 17 % higher in juveniles compared to adults (n = 454). In adults, invertivores has higher mercury levels compared to omnivores. Mercury was highest at low-elevation sites near water, however mercury was detected in all birds, including those in the high elevations (1,000-2,000 m). Relative trophic position, calculated from δ (15)N, ranged from 2.13 to 4.87 across all birds. We fitted linear mixed-effects models to the data separately for juveniles and year-round resident adults. In adults, mercury concentrations were 2.4 times higher in invertivores compared to omnivores. Trophic position was the main effect explaining mercury levels in juveniles, with an estimated 0.18 ± 0.08 μg g(-1) increase in feather mercury for each one unit rise in trophic position. Our research demonstrates that mercury is biomagnifying in birds within this terrestrial mountainous system, and further research is warranted for animals foraging at higher trophic levels, particularly those associated with aquatic environments downslope from montane areas receiving high mercury deposition.

Abundance and population density are fundamental pieces of information for population ecology and species conservation, but they are difficult to estimate for rare and elusive species. Mark--resight models are popular for estimating population abundance because they are less invasive and expensive than traditional mark-recapture. However, density estimation using mark-resight is difficult because the area sampled must be explicitly defined, historically using ad hoc approaches. We developed a spatial mark--resight model for estimating population density that combines spatial resighting data and telemetry data. Incorporating telemetry data allows us to inform model parameters related to movement and individual location. Our model also allows <100% individual identification of marked individuals. We implemented the model in a Bayesian framework, using a custom-made Metropolis-within-Gibbs Markov chain Monte Carlo algorithm. As an example, we applied this model to a mark--resight study of raccoons (Procyon lotor) on South Core Banks, a barrier island in Cape Lookout National Seashore, North Carolina, USA. We estimated a population of 186.71 +/- 14.81 individuals, which translated to a density of 8.29 +/- 0.66 individuals/km2 (mean +/- SD). The model presented here will have widespread utility in future applications, especially for species that are not naturally marked.

False positive errors are a significant component of many ecological data sets, which in combination with false negative errors, can lead to severe biases in conclusions about ecological systems. We present results of a field experiment where observers recorded observations for known combinations of electronically broadcast calling anurans under conditions mimicking field surveys to determine species occurrence. Our objectives were to characterize false positive error probabilities for auditory methods based on a large number of observers, to determine if targeted instruction could be used to reduce false positive error rates, and to establish useful predictors of among-observer and among-species differences in error rates. We recruited 31 observers, ranging in abilities from novice to expert, who recorded detections for 12 species during 180 calling trials (66,960 total observations). All observers made multiple false positive errors, and on average 8.1% of recorded detections in the experiment were false positive errors. Additional instruction had only minor effects on error rates. After instruction, false positive error probabilities decreased by 16% for treatment individuals compared to controls with broad confidence interval overlap of 0 (95% CI:--46 to 30%). This coincided with an increase in false negative errors due to the treatment (26%;--3 to 61%). Differences among observers in false positive and in false negative error rates were best predicted by scores from an online test and a self-assessment of observer ability completed prior to the field experiment. In contrast, years of experience conducting call surveys was a weak predictor of error rates. False positive errors were also more common for species that were played more frequently but were not related to the dominant spectral frequency of the call. Our results corroborate other work that demonstrates false positives are a significant component of species occurrence data collected by auditory methods. Instructing observers to only report detections they are completely certain are correct is not sufficient to eliminate errors. As a result, analytical methods that account for false positive errors will be needed, and independent testing of observer ability is a useful predictor for among-observer variation in observation error rates.

The recent surge in the development and application of species occurrence models has been associated with an acknowledgment among ecologists that species are detected imperfectly due to observation error. Standard models now allow unbiased estimation of occupancy probability when false negative detections occur, but this is conditional on no false positive detections and sufficient incorporation of explanatory variables for the false negative detection process. These assumptions are likely reasonable in many circumstances, but there is mounting evidence that false positive errors and detection probability heterogeneity may be much more prevalent in studies relying on auditory cues for species detection (e.g., songbird or calling amphibian surveys). We used field survey data from a simulated calling anuran system of known occupancy state to investigate the biases induced by these errors in dynamic models of species occurrence. Despite the participation of expert observers in simplified field conditions, both false positive errors and site detection probability heterogeneity were extensive for most species in the survey. We found that even low levels of false positive errors, constituting as little as 1% of all detections, can cause severe overestimation of site occupancy, colonization, and local extinction probabilities. Further, unmodeled detection probability heterogeneity induced substantial underestimation of occupancy and overestimation of colonization and local extinction probabilities. Completely spurious relationships between species occurrence and explanatory variables were also found. Such misleading inferences would likely have deleterious implications for conservation and management programs. We contend that all forms of observation error, including false positive errors and heterogeneous detection probabilities, must be incorporated into the estimation framework to facilitate reliable inferences about occupancy and its associated vital rate parameters.

Many factors affect the number of birds detected on point count surveys of breeding songbirds. The magnitude and importance of these factors are not well understood. We used a bird song simulation system to quantify the effects of detection distance, singing rate, species differences, and observer differences on detection probabilities of birds detected by ear. We simulated 40 point counts consisting of 10 birds per count for five primary species (Black-and-white Warbler Mniotilta varia, Black-throated Blue Warbler Dendroica caerulescens, Black-throated Green Warbler Dendroica virens, Hooded Warbler Wilsonia citrina, and Ovenbird Seiurus aurocapillus) over a range of 15 distances (34-143 m). Songs were played at low (two songs per count) and high (13-21 songs per count) singing rates. Detection probabilities averaged across observers ranged from 0.60 (Black-and-white Warbler) to 0.83 (Hooded Warbler) at the high singing rate and 0.41 (Black-and-white Warbler) to 0.67 (Hooded Warbler) at the low singing rate. Logistic regression analyses indicated that species, singing rate, distance, and observer were all significant factors affecting detection probabilities. Singing rate x species and singing rate X distance interactions were also significant. Simulations of expected counts, based on the best logistic model, indicated that observers detected between 19% (for the worst observer, lowest singing rate, and least detectable species) and 65% (for the best observer, highest singing rate, and most detectable species) of the true population. Detection probabilities on actual point count surveys are likely to vary even more because many sources of variability were controlled in our experiments. These findings strongly support the importance of adjusting measures of avian diversity or abundance from auditory point counts with direct estimates of detection probability.

Fire suppression has negatively impacted thousands of acres of private and public lands in the United States. As a case study, the New Jersey Pine Barrens (NJPB) are a disturbance driven ecosystem that is experiencing serious ecological implications due to a loss of traditional forest thinning activities such as harvesting for forest products or thinning for wildfire fuel-load reduction measures coupled with a long-standing philosophy of fire suppression and dormant-season prescribed burning. Dense closed-canopy forest conditions, dissimilar to historic open-canopy forests of the NJPB, have reduced abundance and diversity of certain flora and fauna, including regionally imperiled breeding birds. In recent years, active forest stewardship (e.g., thinning, clear-cutting, and burning) has occurred on private and some public lands within the NJPB; however, the impact of such management on breeding birds is unclear due to a paucity of research on this subject within the NJPB. During 2012, 2013, 2016, and 2017, we conducted repeat-visit point counts (n = 1,800) for breeding songbirds across 75 control and 75 treatment sites within the NJPB to assess the influence of forest structure at three strata levels (groundcover, midstory profile, and canopy) on breeding bird communities. Specifically, we constructed a hierarchical community abundance model within a Bayesian framework for Bird Conservation Region (BCR) 30 priority upland birds (n = 12) within three species suites: Forested Upland, Scrub-Shrub (or Young Forest), and Grassland. At the community level, we found a negative relationship between bird abundance and live tree basal area. At the BCR 30 suite level, we found no relationship between Forested Upland suite-level abundance and any of the measured covariates; however, we found a negative relationship between percentage of woody groundcover and Scrub-Shrub suite-level abundance, and negative relationship between horizontal visual obstruction at 2 m above ground level and Grassland suite-level abundance. Furthermore, the two latter species suites exhibited a strong negative relationship with basal area. We recommend active forest stewardship that specifically targets opening the canopy to achieve basal areas between ~0–15 m2/ha via selective thinning, shelter cutting, and small-scale clear cutting. Mechanical treatment and prescribed burning would produce such conditions and have the added benefit of reducing fuel loads across this ~4,500 km2 landscape as well as assisting in carbon defense strategies for the region. [ABSTRACT FROM AUTHOR]

Species of Pterygodermatites are spirurid nematodes that have expanded their geographic distribution worldwide. They infect a variety of mammalian definitive hosts with few reports of potential paratenic infections in amphibian and reptile hosts. In this study, we report Pterygodermatites sp. larvae identified in free-ranging, invasive Cuban treefrogs (Osteopilus septentrionalis), from central Florida, United States. Encysted larvae were recovered from the skeletal muscle and/or the coelomic cavity of three frogs; molecular characterization of the small subunit (18S) ribosomal RNA and cytochrome oxidase I genes of the parasites matched reported sequences of Pterygodermatites (Mesopectines) whartoni (Tubangui, 1931). This is a parasite native to Southeastern Asia and to the best of the authors' knowledge, it is the first report of the species in the New World. The recovery of invasive Pterygodermatites from invasive Cuban treefrogs in North America highlights the growing concern regarding the potential impact non-native parasites and invasive species may have on native wildlife populations. [ABSTRACT FROM AUTHOR]

Domestic cats (Felis catus) thrive at high densities alongside humans in urban and rural environments and are responsible for excessive wildlife predation worldwide. As urbanisation and farmland expands, and domestic cats inevitably reach previously unoccupied habitats, management plans will rely on understanding cat ranging behaviours. Cat movements and habitat selection may differ depending on their surroundings, and consequently, we sought to assess how male and female cat behaviours varied during different seasons in urban, suburban, and rural environments. In cities and farmland in the UK, the location of 56 owned cats (26 F:30 M) was recorded every 5 min for a total of 5237 h using GPS collars (454 ± 25 fixes over c. 4 days per individual). Urban and rural cats exhibited similar patterns of home ranges, maximum distances travelled from their owner's house, and habitat selection, where they selected for built-up areas with good cover and avoided open spaces. Cats spent an average of 75% of their time outside their owners' house or garden and therefore had great potential to encounter wild prey. Males in rural areas were almost twice as active than other males but all exhibited crepuscular activity patterns compared to cathemeral or diurnal females. In summer, cats had smaller home ranges and were more nocturnal, poentially concentrating their impacts around core areas during hotter months. Similarities in cat ranging behaviours across the urban–rural gradient suggest management plans can be equally applied in areas alongside cities as well as farmland. Buffer or exclusion zones of 750 m around protected areas would exclude 95% of cats, but specialised management, such as periodic confinement during specific active periods, could prove effective during vulnerable prey species' breeding seasons. These findings improve our understanding of how cat ranging is affected by urbanisation under seasonal variation, and can be used to tailor management strategies as new species and populations are exposed to domestic cat predation. [ABSTRACT FROM AUTHOR]

Density and population estimates aid in conservation and stakeholder communication. While free and broadly available community science data can effectively inform species distribution models, they often lack the information necessary to estimate imperfect detection and area sampled, thus limiting their use in fine-scale density modeling. We used structured distance-sampling surveys to model detection probability and calculate survey-specific detection offsets in community science models. We estimated density and population for 16 songbird species under three frameworks: (1) a fixed framework that assumes perfect detection within a specified survey radius, (2) an independent framework that calculates offsets from an independent source, and (3) a calibration framework that calculates offsets from supplemental surveys. Within the calibration framework, we examined the effects of calibration dataset size and data pooling. Estimates of density and population size were consistently biased low in the fixed framework. The independent and calibration frameworks produced reliable estimates for some species, but biased estimates for others, indicating discrepancies in detection probability between structured and community science surveys. The calibration framework produced reliable population estimates with as few as 10 calibration surveys with positive detections. Data pooling dramatically decreased bias. This study provides conservationists and managers with a cost-effective method of estimating density and population. [ABSTRACT FROM AUTHOR]

Black rats (Rattus rattus) are one of the most widespread invasive animals and have been implicated in the decline of species representing several wildlife taxa, particularly on islands. However, their impact on more closely related species, i.e. rodents, via competition is less well-understood. Using diet similarity as a metric of competition for food resources, we used stable isotopes to compare diets of two populations of black rats to diets of two endangered populations of rice rats (Oryzomys palustris natator and Oryzomys palustris sanibeli) in southern Florida, USA. Specifically, we analysed hair samples from 32 rice rats and 35 black rats for carbon (δ13C) and nitrogen (δ15N) isotopes. In addition, we analysed samples of 129 potential food items to characterise rodent diets using stable isotope mixing models. Despite considerable overlap in isotope-space, we observed differences between rice rats and black rats in the relative composition of plant and animal foods. Specifically, the diets of both populations of rice rats consisted of mostly animal foods, whereas the diets of black rats consisted mostly of plants. In combination with previous work revealing temporal niche partitioning, our results suggest competition between invasive black rats and endangered native rodents may be limited. As such, expensive and logistically complicated efforts to control black rats may have limited success for conserving endangered rodents. [ABSTRACT FROM AUTHOR]

Copyright of Caldasia is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The number of offspring parents rear varies considerably among closely related lineages, individuals, and even reproductive events by one individual. Constraints can come at any point, from the costs of producing a large clutch to the cost of caring for a large brood of dependent young. We report here on observations of the early phase of a reproductive cycle in a captive colony of Oophaga pumilio, a poison frog with offspring entirely dependent on maternally provisioned trophic eggs. We tracked reproductive clutches, and found that while clutch and egg size were variable, neither predicted the success of a clutch; there was also no evidence of a trade-off between clutch and egg size. Larger eggs did, however, produce larger tadpoles, and when parents transported only a subset of the brood to nurseries, the tadpoles they moved were larger than the ones they did not. Adaptive adjustment of parental investment is a key life-history trait, and a complete accounting of the way families are constructed is key to understanding the evolution of parental care, parental favoritism, and cooperation and conflict among closely related individuals. [ABSTRACT FROM AUTHOR]

Background: We investigated the effects of a calcium-fortified beverage supplemented over 12 months on body composition in postmenopausal women (n = 37, age = 48-75 y)., Methods: Body composition (total-body percent fat, %FatTB; abdominal percent fat, %FatAB) was measured with dual energy x-ray absorptiometry. After baseline assessments, subjects were randomly assigned to a free-living control group (CTL) or the supplement group (1,125 mg Ca++/d, CAL). Dietary intake was assessed with 3-day diet records taken at baseline and 12 months (POST). Physical activity was measured using the Yale Physical Activity Survey., Results: At 12 months, the dietary calcium to protein ratio in the CAL group (32.3 +/- 15.6 mg/g) was greater than the CTL group (15.2 +/- 7.5 mg/g). There were no differences from baseline to POST between groups for changes in body weight (CAL = 0.1 +/- 3.0 kg; CTL = 0.0 +/- 2.9 kg), %FatTB (CAL = 0.0 +/- 2.4%; CTL = 0.5 +/- 5.4%), %FatAB (CAL = -0.4 +/- 8.7%; CTL = 0.6 +/- 8.7%), or fat mass (CAL = 1.3 +/- 2.6 kg; CTL = 1.3 +/- 2.7 kg)., Conclusion: These results indicate that increasing the calcium to protein ratio over two-fold by consuming a calcium-fortified beverage for 12 months did not decrease body weight, body fat, or abdominal fat composition in postmenopausal women.

Copyright of Huitzil: Journal of Mexican Ornithology / Revue d'Ornithologie Mexicaine is the property of Sociedad para el Estudio y Conservacion de las Aves en Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Context. Where conservation efforts are undertaken to decrease downward trends in fish populations, comparatively few resources are directed to small-bodied cryptic species. The true extent of the decline of many of these species is therefore often unknown. Where surveys have occurred, they are frequently limited by budget and hence effort. Consequently, there is a risk that rare species may not be physically captured despite their presence at a site. Such an outcome has dire consequences for the conservation of remnant populations of threatened fish. To counter possible false negative detections, environmental DNA is increasingly being used in conjunction with, or as a precursor to, physical surveys. The Southern Purple-spotted Gudgeon (Mogurnda adspersa) is a small, threatened freshwater fish native to Australia. Recent surveys captured M. adspersa in two highly turbid waterbodies in north-central Victoria. This capture represented the first detection of the species in the state in more than 20 years. Because these waterbodies are part of a network of hydrologically connected systems, it was suspected that the species likely had a broader distribution in the region. Aims. To develop a probe-based eDNA assay for M. adspersa and compare its sensitivity against a physical sampling program. Methods. Detection (presence/absence) between eDNA and traditional surveys was compared across multiple sites. Key results. eDNA presents an effective tool for determining the presence of M. adspersa. The eDNA survey demonstrated significant clustering of eDNA detections towards the outlets of lakes sampled, suggesting concentrated eDNA at this point, or that, due to the channels being shallower, the eDNA of resident individuals may be less diluted. Conclusions. Based on these results, future survey of rare, cryptic species in highly turbid lake systems should in the first instance include a broad scale eDNA survey, with sampling concentrated at outlet channels. Implications. The likely most cost-effective approach to determining the presence/absence of rare species in lake systems is the collection of eDNA samples at outlet channels. [ABSTRACT FROM AUTHOR]

Context. Accurately estimating wildlife roadkill is necessary to compare differentroads, periods, and species, and to plan and assess mitigation effectiveness. We must account for the two main sources of errors associated with carcass sampling – carcass detection and persistence. Open-population models are used to estimate abundance, survival probabilities, and recruitment in living animal populations, accounting for imperfect detection, and they can be used in the context of animal fatalities. Aims. The aim of this study was to explore an open-population approach to estimate comparable roadkill rates from carcass capture–recapture data, accounting for carcass detection and persistence. Methods. We surveyed carcasses of the white-eared opossum (Didelphis albiventris) and blackand-white tegu lizard (Salvator merianae) on four road stretches using two sampling designs with different number of visits and sampling sessions. Carcasses were marked to be recaptured over visits within the same sampling session,resulting in a capture history for each carcass. Encounter history data were modelled using the superpopulation formulation of the open-population capture–recapture model under Bayesian inference for different datasets. A daily roadkill rate per kilometre was derived from the model entry probability estimate. Key results. We estimated a daily roadkillrate with 1501 captures from 447 opossum carcasses and 511 captures from 218 tegu carcasses. For full data, mean carcass detection overthe sessionsranged from 0.49 to 0.85 forthe opossum and from 0.27 to 0.80 for the tegu, and mean carcass persistence ranged from 0.60 to 0.94 forthe opossum and from 0.64 to 0.91 for the tegu. Scenarios with more occasions and captures increased precision of roadkill rates. Conclusions. We were able to explicitly estimate roadkill rates using an open-population capture– recapture model under a Bayesian framework. It provides accurate roadkill numbers for a known time frame and road extension, accounting for imperfect detection and its associated uncertainty. Under scenarios of few carcasses, users should consider a higher number of occasions. Implications. Not addressing carcass sampling errors or simplistically addressing them (e.g. only once during the study period) could mislead mitigation efforts. The approach used here can be used to estimate fatalities in other locations, such as windfarms and powerlines, for which repeated observations of marked carcasses are an option. [ABSTRACT FROM AUTHOR]

Road and pipeline infrastructure development for natural gas extraction often results in forest fragmentation, which could negatively influence habitat quality for many amphibian species. We investigated occurrence dynamics of the eastern red-backed salamander Plethodon cinereus in relation to natural gas pipeline rights-of-way (ROWs) and forest structure characteristics in northern Pennsylvania, USA. We sampled 80 sites across two study areas by using coverboards, with each site containing sampling plots at the center of the ROW, the edge of the ROW, and 10 m and 30 m into the adjacent forest. We assessed the influence of ROW age, ROW width, distance from ROW, and five forest structure characteristics on plot occupancy probability. Eastern red-backed salamander occupancy probability decreased with ROW age and increased with distance from ROW. Our results indicate that eastern red-backed salamanders are negatively influenced by forest fragmentation for natural gas ROWs. Moreover, responses were time dependent, with occupancy probability declining with ROW age. Due to low detections, we were unable to analyze data for the other amphibians and reptiles encountered during the study. Our capture data indicate that ROWs could improve habitat quality for some snake species, but additional research is needed to better understand the influence of ROWs on reptile species. To reduce future forest fragmentation and impacts on eastern red-backed salamander populations, managers could consider placing pipelines along existing linear clearings and enhancing the habitat quality of ROWs for salamanders. [ABSTRACT FROM AUTHOR]

The impact of rainwater harvesting systems on biodiversity in hyperarid North African areas has not been assessed to date despite its demonstrated usefulness. The present study investigated this impact by considering the richness of wintering birds (RWB) in the Tataouine region (pre-Saharan Tunisia). We used data from three sets of variables—rainwater harvesting system type, microhabitat conditions, and topography—to determine the best predictors causing variation in the RWB by means of generalized linear mixed models. Our results show that the jessour system is the most attractive for the wintering bird species, followed by the tabia system, and lastly by the control areas. In the jessour system, RWB is influenced positively by slope and shrub cover and quadratically by tree cover, whereas this richness is affected positively by the extent of the herbaceous layer in the tabia system. In the control areas, RWB is negatively affected by elevation and quadratically affected by tree cover. Variation partitioning (VP) analysis reveals that (i) space is the most robust factor explaining the RWB in control areas (adj. R2 = 0.15, p = 0.001), (ii) microhabitat is central in the tabia system (adj. R2 = 0.10, p = 0.001), and (iii) the shared fraction between microhabitat and space is relevant in the jessour systems (adj. R2 = 0.20). Specific management actions, especially preserving, maintaining, and promoting these traditional systems, are suggested to improve the attraction of wintering bird species to the Tataouine region. The implementation of a scientific watch system is recommended to understand how changes take place in such an arid environment. [ABSTRACT FROM AUTHOR]

Context: Brown-headed cowbirds (Molothrus ater), through brood parasitism, can exert extrinsic population growth pressures on North American songbirds. Cowbird removal programs may reduce parasitism rates on host species but can be expensive and difficult to implement throughout a host species' breeding range. Aim: We estimated cowbird abundance and nest parasitism rates within Kirtland's warbler (Setophaga kirtlandii) primary breeding range in Michigan, USA, and determined the maximum sustainable parasitism rate for Kirtland's warblers under several spatially structured cowbird removal designs. Methods: We conducted point counts to estimate cowbird abundance and monitored nests to quantify nest parasitism rates during 2019–2021. We used the modelling software STELLA to determine the maximum sustainable parasitism rate for Kirtland's warblers under different spatially structured cowbird removal scenarios (complete, core-only, and no removal). Key results: Cowbird abundance and parasitism rates remained low following cowbird trap closures in 2018. In the simulation study, complete removal was the most robust scenario with no replications having <1000 Kirtland's warbler males. The core-only removal scenario had a substantially higher sustainable parasitism rate in the peripheral breeding area than the no removal scenario. Assumed hatch-year dispersal distance had the greatest impact on the maximum sustainable parasitism rate in the core-only scenario. Conclusions: Low cowbird abundance and nest parasitism following suspension of cowbird removal efforts showed resuming the removal program may not be required in the short-term. If cowbird abundance increases, however, adaptive cowbird removal programs can be used to sustain Kirtland's warbler populations long-term. Implications: Our results indicate that incorporating spatial structure of host species' habitat into designing cowbird removal programs may minimise costs of cowbird management while sustaining populations of Kirtland's warbler and possibly other host species that are affected by brood parasitism. Brood parasitism can strongly impact songbird productivity and was a major factor resulting in the historical decline of the Kirtland's warbler. We found contemporary cowbird brood parasitism rates were around 1.5% within the primary breeding area of the Kirtland's warbler, the species can withstand a reduction in productivity of 13–18% before declining, and high parasitism rates in the peripheral breeding area are sustainable long-term if cowbird removal occurs in the core breeding area. Our study provides parasitism thresholds to assist with development of management strategies to ensure long-term viability of this conservation-reliant species. Photograph by Nathan W. Cooper. [ABSTRACT FROM AUTHOR]

Cross-national analyses test hypotheses about the drivers of variation in national outcomes. However, since nations are connected in various ways, such as via spatial proximity and shared cultural ancestry, cross-national analyses often violate assumptions of non-independence, inflating false positive rates. Here, we show that, despite being recognised as an important statistical pitfall for over 200 years, cross-national research in economics and psychology still does not sufficiently account for non-independence. In a review of the 100 highest-cited cross-national studies of economic development and values, we find that controls for non-independence are rare. When studies do control for non-independence, our simulations suggest that most commonly used methods are insufficient for reducing false positives in non-independent data. In reanalyses of twelve previous cross-national correlations, half of the estimates are compatible with no association after controlling for non-independence using global proximity matrices. We urge social scientists to sufficiently control for non-independence in cross-national research. Nations are connected in many ways, yet cross-national analyses often assume they are independent. Here, the authors show that previous studies may not have sufficiently accounted for this non-independence of nations. [ABSTRACT FROM AUTHOR]

Vultures are key to the functioning of ecosystems but they are assessed to be threatened globally and their numbers are at-risk due to changes in habitat and other factors. This study focuses on identifying localized conservation status changes in vultures over a decade (2011–2020) by assessing habitat occupancy and population in Uttar Pradesh using PRESENCE, GeoCAT and MaxEnt tools. The overall vulture population increased with differing growth rates across species (11–18%). The Extent of occupancy of Egyptian, Red-headed, and Indian vultures, and Himalayan Griffon increased over the decade but White-rumped and Cinereous vultures showed decrease in this parameter. The occupancy (ψ) and suitable area for Indian, White-rumped and Cinereous vultures decreased while, Egyptian and Red-headed vultures showed gains. Himalayan Griffon showed increased occupancy but decreased suitable area. On the other hand, Area of occupancy components showed improvement in conservation category in the case of Egyptian Vulture and Eurasian Griffon, but deterioration in Slender-billed Vulture. Remaining vultures (Cinereous, Himalayan Griffon, Indian, Red-headed and White-rumped) with continued threatened status were still a cause of concern. Overall, an increasing population coupled with decreasing suitable area indicated the concentration of individuals in smaller areas leading to enhanced extinction risks. This indicated that the imperiled resident Gyps (G. bengalensis, G. indicus and G. tenuirostris) were not recovering post-diclofenac-ban. However, an influx of population without nesting pressure in the wintering habitat indicated a positive future for migratory species. Therefore, management interventions for safeguarding the future of these vulnerable raptors should be concentrated in potentially suitable areas too as predicted in this study. [ABSTRACT FROM AUTHOR]

We investigated the effect of observer error on four commonly used species diversity measures: species richness, Shannon–Weiner diversity, Shannon–Weiner evenness and Simpson's index of diversity. We also evaluated how observer error affects inferences derived from multivariate analyses of species–abundance relationships as determined by non-metric multidimensional scaling (NMS) ordination. Grassland vegetation was sampled by three different botanists at two national park units in Missouri and Kansas, USA. The same plots were sampled by two of the botanists, who compiled lists of species composition and estimated foliar cover. Differences in the data records were then compared. Pseudoturnover (i.e. apparent turnover due to observer error) ranged from 17.1% to 22.1%, and differences in cover class estimation ranged from 21.5% to 30.5%. The percentage difference in species diversity measures between pairs of observers depended on how data were summarized, but were always <20%, and often <10%. Based on these results, species diversity metrics are affected to a relatively smaller extent by observer error than turnover indices. Turnover indices, however, contain more information because they track individual species, whereas species are interchangeable in most species diversity indices. Thus, less of the error is identified because of how species diversity indices are calculated. NMS ordinations revealed that while the characterizations of some plots by different observers were similar, differences between observers' records for other plots resulted in greater separation in ordination space. Points representing one observer's records were often shifted in ordination space in the same direction compared with the other observer. [ABSTRACT FROM AUTHOR]

Context: Within dynamic ecosystems, research into how land use changes and patterns affect species diversity has led to a suite of ecological hypotheses to assess species-landscape associations. The Habitat Amount Hypothesis suggests that it is the total amount of habitat, regardless of configuration, whereas the Multi-dimensional Hypothesis suggests it is the suite of local, landscape, and landform characteristics that have the greatest influence on species diversity within its local landscape. Objectives: Our study aims to understand how landscape pattern influences species abundance, in the context of these two competing hypotheses on priority avian species in working forest landscapes of the southeastern United States. Methods: To examine these hypotheses, we conducted bird point counts and vegetation surveys in short-rotation loblolly pine (Pinus taeda) forests in east-central Mississippi during 2019–2020 and used abundance and richness models to assess avian species associations to amount vs. configuration of habitat in a 2 km2 landscape. Results: We found that habitat amount alone did not exhibit consistent positive associations with species abundance for both early-successional and mature forest associated avian communities. Most target species exhibited positive associations with patch proximity, measured by Euclidean distance, and proximity-area index. However, measures of species richness showed no association with amount or proximity. Associations with landform features generally had positive influences on early-successional species than mature-pine priority species. Conclusions: The dynamic mosaic of forest stand ages may be sufficient in providing habitat needs such that measures of richness are not driven by amount and proximity at the 2 km2 scale in this working landscape. However, influences of proximity and landform on priority species abundance warrant further research to assess potential drivers of associations with stand proximity and effects of amount and proximity on measures of species diversity across scales. Given the growing demand for forest products, sustainable forestry guidelines that consider proximity of stands in similar age classifications could enhance landscape suitability for some target species. [ABSTRACT FROM AUTHOR]

Abundance surveys are commonly used to estimate plant or animal densities and frequently require estimating detection probabilities to account for imperfect detection. The estimation of detection probabilities requires additional measurements that take time, potentially reducing the efficiency of the survey when applied to high-density populations. We conducted quadrat, removal, and distance surveys of zebra mussels (Dreissena polymorpha) in three central Minnesota lakes and determined how much survey effort would be required to achieve a pre-specified level of precision for each abundance estimator, allowing us to directly compare survey design efficiencies across a range of conditions. We found that the required sampling effort needed to achieve our precision goal depended on both the survey design and population density. At low densities, survey designs that could cover large areas but with lower detection probabilities, such as distance surveys, were more efficient (i.e., required less sampling effort to achieve the same level of precision). However, at high densities, quadrat surveys, which tend to cover less area but with high detection rates, were more efficient. These results demonstrate that the best survey design is likely to be context-specific, requiring some prior knowledge of the underlying population density and the cost/time needed to collect additional information for estimating detection probabilities. [ABSTRACT FROM AUTHOR]

Context: Rodents in many parts of the world perform an important ecosystem function as dispersers of mycorrhizal fungal spores. These fungi are vital to nutrient uptake in plant communities, but many of the fungal taxa that form these associations have fruiting bodies that are reliant on animals for their spore dispersal. Aims: Numerous studies have focused on the ecological importance of Australian marsupials (especially members of the Potoroidae) for the dispersal of these ecologically important fungi. We chose to focus this study on the role of murid rodents in the dispersal of these fungi in eastern Australia. Methods: To compare fungal taxa in murid diets, we trapped rodents in three regions of eastern Australia; our study sites spanned over 2000 km from temperate eucalypt forests to tropical eucalypt and tropical rainforest habitats. We performed microanalysis on all scats to determine whether fungi were consumed and which taxa were being eaten. Statistical analysis was conducted to investigate trends in levels of mycophagy among species and habitats. Key results: We examined 10 rodent species, and all were shown to ingest mycorrhizal fungi to varying degrees. The diversity, abundance and specific fungal taxa consumed varied depending on the site and forest type. In drier forests dominated by Eucalyptus spp., the fungal taxa consumed and dispersed were primarily ectomycorrhizal; in wetter rainforest habitats, the fungal diversity consumed was far lower and included primarily vesicular arbuscular fungi. We provide the first evidence of mycophagy by grassland melomys (Melomys burtoni) and Cape York melomys (Melomys capensis). Conclusions: Our findings highlight the importance of rodents as dispersers of mycorrhizal fungi across a variety of habitats from temperate to tropical forests of eastern Australia. Implications: This study increases the existing knowledge of rodent diets and habitat requirements. It also provides a new angle for mammal conservation efforts, given the vital nature of the ecosystem service provided by these small and frequently overlooked mammals. Fungi are vital to the nutrient uptake in forests, but the role of rodents in spore dispersal in eastern Australia remains incompletely studied. Our study highlighted the importance of 10 species of rodents as dispersers of mycorrhizal fungi across a variety of habitats, including from temperate to tropical forests. We also provide the first records of fungus consumption by two species. Photographs by Todd F. Elliott. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a disease of primary concern for Hawaiian monk seals (Neomonachus schauinslandi), due to its apparently acute lethality and especially heavy impacts on breeding female seals. The disease-causing parasite, Toxoplasma gondii, depends on cats to complete its life cycle; thus, in order to understand how this pathogen infects marine mammals, it is essential to understand aspects of the terrestrial ecosystem and land-to-sea transport. In this study, we constructed a three-tiered model to assess risk of Hawaiian monk seal exposure to T. gondii oocysts: (1) oocyst contamination as a function of cat population characteristics; (2) land-to-sea transport of oocysts as a function of island hydrology, and (3) seal exposure as a function of habitat and space use. We were able to generate risk maps highlighting watersheds contributing the most to oocyst contamination of Hawaiian monk seal habitat. Further, the model showed that free-roaming cats most associated with humans (pets or strays often supplementally fed by people) were able to achieve high densities leading to high levels of oocyst contamination and elevated risk of T. gondii exposure., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Context: Accurate and precise monitoring practises are key for effective wildlife conservation management; providing reliable estimates of spatiotemporal changes in species abundance on which sound decision-making can be based. Advancements in drone and satellite technology are providing new standards for survey accuracy and precision and have great potential for enhancing population monitoring of numerous difficult to survey species. Flying-foxes (Pteropus spp.) are large bats that roost in groups of a few hundred to many thousands in the canopies of trees, where they are difficult to census accurately and precisely by human observers. Globally, 35 of the 64 flying-fox species are listed as threatened under the IUCN Red List of Threatened Species, and reliable monitoring methods are needed for the effective management of this ecologically important group. Aims: Recently, we showed that drone-acquired thermal imagery can be used to count flying-foxes in their roost with high accuracy and precision. In the present study, we aimed to assess the accuracy and precision of whole colony counts derived from ground-based counting methods against reference counts derived from drone-acquired thermal imagery. Methods: We evaluated the relationship between ground-based counts by two groups of human observers to highly accurate and precise counts derived from drone-acquired thermal orthomosaics for 25 counts conducted across seven flying-fox roosts throughout the Greater Sydney region, Australia. Key results: We found that ground-based counts by human observers were positively correlated with those obtained from concurrent drone-acquired thermal imagery. However, drone-acquired estimates of colony size were 2.05 and 1.92 times higher than ground-based counts by the experimenter and Australian government counters respectively. When compared against drone-acquired reference counts, the precision (coefficient of variation) of ground-based counts was 26.3% when conducted by a single counter and 55.1% when conducted by multiple counters. Conclusions: Our research indicates that ground-based counting methods underestimate true population sizes by substantial margins and have limited precision. Drone-based monitoring provides highly accurate and precise population estimates, and thus is expected to yield more reliable information on flying-fox abundance and allow for trends to be established over shorter timescales. Implications: Using ground counting methods alone, population trends can only be established with significance after protracted periods of monitoring. Incorporating the use of thermal drones into current monitoring practises would enhance the capacity to detect population trends earlier and more accurately, so that conservation management can more effectively respond. Reliable monitoring of trends in flying-fox populations is essential for flying-fox conservation. By comparing ground-based counting methods with reference counts derived from drone-acquired thermal imagery, we found that ground-based methods severely underestimate the true number of flying-foxes in roosts and had very limited precision. Drone-based monitoring of flying-foxes can facilitate more effective conservation management of these ecologically important species. Photographs by Justin A. Welbergen (left) and Eliane D. McCarthy (right). [ABSTRACT FROM AUTHOR]

Bumble bees (Hymenoptera: Apidae, Bombus Latreille) perform important ecological services in both managed and natural ecosystems. Anthropogenically induced change has altered floral resources, climate, and insecticide exposure, factors that impact health and disease levels in these bees. Habitat management presents a solution for improving bee health and biodiversity, but this requires better understanding of how different pathogens and bee species respond to habitat conditions. We take advantage of the washboard of repeated ridges (forested) and valleys (mostly developed) in central Pennsylvania to examine whether local variation in habitat type and other landscape factors influence bumble bee community composition and levels of 4 leading pathogens in the common eastern bumble bee, Bombus impatiens Cresson. Loads of viruses (DWV and BQCV) were found to be lowest in forest habitats, whereas loads of a gut parasite, Crithidia bombi , were highest in forests. Ridgetop forests hosted the most diverse bumble bee communities, including several habitat specialists. B. impatiens was most abundant in valleys, and showed higher incidence in areas of greater disturbance, including more developed, unforested, and lower floral resource sites, a pattern which mirrors its success in the face of anthropogenic change. Additionally, DNA barcoding revealed that B. sandersoni is much more common than is apparent from databases. Our results provide evidence that habitat type can play a large role in pathogen load dynamics, but in ways that differ by pathogen type, and point to a need for consideration of habitat at both macro-ecological and local spatial scales. [ABSTRACT FROM AUTHOR]

The zooplankton community is a widely used bioindicator for the biological assessment of riverine aquatic ecosystems. Phyto-zooplankton interaction and spatially varying river environment parameters perceivably govern their spatial distribution in a large river. This invites the challenge of predicting zooplankton abundance along the river channel. The present article has proposed a geostatistical framework to predict zooplankton abundance along the river course while decoupling phyto-zooplankton relationship from spatial dependency. The strength of secondary data on the river Narmada—a large tropical river in India—has been utilised to accomplish the goal. The nonlinear logistic regression kriging has been found to be the most effective framework. The phyto-zooplankton relationship captured 66% of zooplankton variability, having moderate (37%) residual spatial dependence. The results have shown longitudinally fluctuating spatial variability, which supports the river serial discontinuity concept. The proposed framework has generated smooth zooplankton abundance and sustainability predictive maps that have allowed detection of the change point locations of zooplankton abundance. The map has precisely identified the most productive zone of zooplankton sustainability. The study also has appraised obtaining approximate data in the areas where sampling is infeasible, which will be helpful for location-specific management strategies on a lower spatial scale. [ABSTRACT FROM AUTHOR]

Avian reproductive strategies vary widely, and many studies of life-history variation have focused on the incubation and hatching stages of nesting. Birds make proximate decisions regarding reproductive investment during the laying stage, and these decisions likely constrain and tradeoff with other traits and subsequent behaviors. However, we know relatively little about egg-laying stage behaviors given the difficulty of locating and monitoring nest sites from the onset of laying. We used non-invasive continuous video recording to quantify variation in the egg-laying behaviors of burrowing owls (Athene cunicularia) along a 1400-km latitudinal gradient in western North America. Burrowing owls laid eggs disproportionately in the morning hours, and that tendency was strongest among first eggs in a clutch. However, selection appeared to act more strongly on laying intervals (the time between laying of consecutive eggs) than on the diel time of laying, and laying intervals varied widely among and within clutches. Laying intervals declined seasonally and with increasing clutch size but increased with increasing burrow temperature and as a function of laying stage nest attentiveness, which may be a strategy to preserve egg viability. Laying interval was positively correlated with the duration of hatching intervals, suggesting that laying interval duration is one mechanism (along with timing of incubation onset) that generates variation in hatching asynchrony. Our results lend support to two general hypotheses to explain laying schedules; selection favors laying eggs in the morning, but other selective pressures may override that pattern. These conclusions indicate that allocation decisions during laying are an important part of avian life-history strategies which are subject to energetic constraints and tradeoffs with other traits. [ABSTRACT FROM AUTHOR]

Background Maternal exposure to pesticides during early pregnancy is associated with increased risks of birth defects, while the association between maternal exposure to chemical fertilizer during pregnancy and the risk of birth defects remains unknown. Methods Data were from a population-based birth defects surveillance system between 2007 and 2012 in Pingding County, Shanxi Province, northern China. A total of 14 074 births with 235 birth defects were used to estimate spatial clustering and correlations at the village level. A population-based case–control study of 157 cases with birth defects and 204 controls was performed to investigate the association between maternal chemical fertilizer exposure and the risk of birth defects by a two-level logistic model. Results The total prevalence of birth defects between 2007 and 2012 was 167.0/10 000 births. The spatial analysis indicated a remarkable high-risk area of birth defects in the southeast of Pingding County and the use of chemical fertilizer was associated with the risk of birth defects at the village level. After adjusting for confounders at the individual level, mothers who live in villages with chemical fertilizer application ≥65 tons/y had an increased risk of birth defects (adjusted odds ratio 2.06 [95% confidence interval 1.23 to 3.46]) compared with those of <65 tons/y. Conclusions Our findings suggest that the risk of birth defects may be associated with the use of chemical fertilizer in rural northern China. The findings must be cautiously interpreted and need to be investigated on larger samples. [ABSTRACT FROM AUTHOR]

Context: The introduced red fox has driven the decline or extinction of numerous wildlife species in Australia, yet little information exists on the population densities of foxes in most ecosystems. Fox monitoring programs will differ widely depending on the goals of management, which, in turn, will determine whether the appropriate metric is a density estimate, or some proxy thereof, and the time and resources required. Aims: This study aims to assist wildlife managers to design fit-for-purpose monitoring programs for foxes by providing a better understanding of the utility and precision of various monitoring methods. Methods: We surveyed foxes monthly over four consecutive years in a semi-arid region of Australia by using sand plots, camera traps and GPS telemetry. The resultant data were used to produce population estimates from one count-based method, two spatially explicit methods, and two activity indices. Key results: The incorporation of GPS-collar data into the spatial capture–recapture approaches greatly reduced uncertainty in estimates of abundance. Activity indices from sand plots were generally higher and more variable than were indices derived from camera traps, whereas estimates from N-mixture models appeared to be biased high. Conclusions: Our study indicated that the Allen–Engeman index derived from camera-trap data provided an accurate reflection of change in the underlying fox density, even as density declined towards zero following introduction of lethal control. This method provides an efficient means to detect large shifts in abundance, whether up or down, which may trigger a change to more laborious, but precise, population monitoring methods. If accuracy is paramount (e.g. for reintroduction programs) spatially explicit methods augmented with GPS data provide robust estimates, albeit at a greater cost in resources and expertise than does an index. Implications: Our study demonstrated that the shorter the survey period is, the greater is the likelihood that foxes are present but not detected. As such, if limited resources are available, longer monitoring periods conducted less frequently will provide a more accurate reflection of the underlying fox population than do shorter monitoring periods conducted more often. Foxes threaten the survival of many Australian wildlife species, yet little is known about their population numbers. We monitored a fox population for four consecutive years and compared a variety of monitoring methods and analytical techniques. Our findings will help land managers design fit-for-purpose monitoring programs to better understand the threat posed by foxes and the efficacy of efforts to manage their populations. Photograph by Andrew Carter. [ABSTRACT FROM AUTHOR]

Ongoing urbanization and land transformation drive profound changes in ecosystems worldwide, with wildlife responding in myriad ways. Particularly, functional homogenization of wildlife communities due to these widespread changes may reduce biodiversity and urban ecosystem resilience. However, there are benefits of urbanization (e.g., increased resources and survival) for some mammal species, likely supported by corresponding traits that facilitate the exploitation of human-dominated landscapes. Using data collected simultaneously from 107 sites throughout the contiguous United States, we explored how urban development, agricultural development, and environmental factors affected mammalian functional diversity (i.e., richness, evenness, and divergence of effect traits) and mean species' traits at two spatial scales. Although we expected that urbanization would lead to mammal community functional homogenization, we found that urban development was positively associated with functional richness at the camera-site and all three functional metrics at the camera-array scales, whereas environmental variables (i.e., primary productivity, temperature) were not associated with any functional diversity metric. Sampling locations with greater urban development were associated with mammals that had smaller average home ranges, smaller average body sizes, and decreased mean rates of carnivory and scavenging. Identifying the effects of anthropogenic development on ecosystem functioning, as mediated by species' traits, is crucial as urban landscapes continue to expand globally. [ABSTRACT FROM AUTHOR]

The jaguar is listed as endangered in Mexico. However, population estimates and conservation initiatives have relied on data obtained from Protected Areas (PA) covered by humid tropical forests of southern Mexico. In this context, the objectives were: 1) to estimate jaguar density for the last wilderness ecoregion of central-western Mexico, 2) quantify the capture rate of potential prey of jaguar, 3) evaluate the percentage of native vegetation cover in the Effective Sampling Area (ESA), and 4) review the density estimates of jaguars in Mexico. Jaguar density was evaluated in an ESA of 156 km2, using 'Capture–Recapture' (C-R) and 'Spatially Explicit Capture–Recapture' (SECR) models. We obtained 28 photographic captures of two females, in which models averaged a density of 1.01 ± 0.41 ind/100 km2. The mid and large size-mammal community included 14 species with forested landscape and vegetation measured at 90%. The scientific literature includes 30 jaguar density estimates in Mexico, with 22 (85%) inside Protected Areas. Average density among all estimates in México is 2.85 ± 1.82 STD. For the first time, our density estimates provide reliable population-level data for one key region for jaguar conservation efforts in the northern hemisphere. As low-density estimates were obtained, this population is highly vulnerable, deserving priority attention by conservation strategies at a national level. RESUMEN El jaguar está en peligro de extinción en México. Sin embargo, las estimaciones de sus poblaciones y las iniciativas de conservación se han basado en datos obtenidos en Áreas Protegidas (AP) cubiertas por bosques tropicales húmedos del sur de México. En este contexto, los objetivos fueron: 1) estimar la densidad de jaguares para la última ecorregión silvestre del centro-oeste de México, 2) cuantificar la tasa de captura de presas potenciales del jaguar, 3) evaluar el porcentaje de cobertura de vegetación nativa en el Área Efectiva de Muestreo (ESA en ingles) y 4) revisar las estimaciones de densidad de jaguares en México. La densidad del jaguar se evaluó en una ESA de 156 km2, utilizando modelos de "Captura-Recaptura" (C-R) y "Captura-Recaptura Espacialmente Explícitos" (SECR en ingles). Obtuvimos 28 capturas fotográfícas de dos hembras, en las cuales los modelos promediaron una densidad de 1.01 ± 0.41 ind/100 km2. La comunidad de mamíferos de tamaño mediano y grande incluyó 14 especies con un paisaje boscoso y una cobertura vegetal de 90%. La literatura científica incluye 30 estimaciones de densidad de jaguares en México, 22 (85%) dentro de Áreas Protegidas. La densidad promedio entre todas las estimaciones en México es de 2.85 ± 1.82 ETS. Por primera vez, nuestras estimaciones de densidad proporcionan datos confiables a nivel de población para una región clave en los esfuerzos de conservación del jaguar en el hemisferio norte. Debido a la baja densidad reportada en este estudio, esta población es altamente vulnerable y merece una atención prioritaria por parte de las estrategias de conservación a nivel nacional. [ABSTRACT FROM AUTHOR]

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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]

We address two computational issues common to open-population N-mixture models, hidden integer-valued autoregressive models, and some hidden Markov models. The first issue is computation time, which can be dramatically improved through the use of a fast Fourier transform. The second issue is tractability of the model likelihood function for large numbers of hidden states, which can be solved by improving numerical stability of calculations. As an illustrative example, we detail the application of these methods to the open-population N-mixture models. We compare computational efficiency and precision between these methods and standard methods employed by state-of-the-art ecological software. We show faster computing times (a ∼ 6 to ∼ 30 times speed improvement for population size upper bounds of 500 and 1000, respectively) over state-of-the-art ecological software for N-mixture models. We also apply our methods to compute the size of a large elk population using an N-mixture model and show that while our methods converge, previous software cannot produce estimates due to numerical issues. These solutions can be applied to many ecological models to improve precision when logs of sums exist in the likelihood function and to improve computational efficiency when convolutions are present in the likelihood function. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Monitoring the occupancy and abundance of wildlife populations is key to evaluate their conservation status and trends. However, estimating these parameters often involves time and resource-intensive techniques, which are logistically challenging or even unfeasible for rare and elusive species that occur patchily and in small numbers. Hence, surveys based on field identification of signs (e.g. faeces, footprints) have long been considered a cost-effective alternative in wildlife monitoring, provided they produce reliable detectability and meaningful indices of population abundance. We tested the use of sign surveys for monitoring rare and otherwise elusive small mammals, focusing on the Cabrera vole (Microtus cabrerae) in Portugal. We asked how sampling intensity affects true positive detection of the species, and whether sign abundance is related to population size. We surveyed Cabrera voles' latrines in 20 habitat patches known to be occupied, and estimated 'true' population size at each patch using DNA-based capture-recapture techniques. We found that a searching rate of ca. 3 min/250m2 of habitat based on adaptive guided transects was sufficient to provide true positive detection probabilities > 0.85. Sign-based abundance indices were at best moderately correlated with estimates of 'true' population size, and even so only for searching rates > 12 min/250m2. Our study suggests that surveys based on field identification of signs should provide a reliable option to estimate occupancy of Cabrera voles, and possibly for other rare or elusive small mammals, but cautions should be exercised when using this approach to infer population size. In case of practical constraints to the use of more accurate methods, a considerable sampling intensity is needed to reliably index Cabrera voles' abundance from sign surveys. [ABSTRACT FROM AUTHOR]

China implemented a strict lockdown policy to prevent the spread of COVID-19 in the worst-affected regions, including Wuhan and Shanghai. This study aims to investigate impact of these lockdowns on air quality index (AQI) using a deep learning framework. In addition to historical pollutant concentrations and meteorological factors, we incorporate social and spatio-temporal influences in the framework. In particular, spatial autocorrelation (SAC), which combines temporal autocorrelation with spatial correlation, is adopted to reflect the influence of neighbouring cities and historical data. Our deep learning analysis obtained the estimates of the lockdown effects as − 25.88 in Wuhan and − 20.47 in Shanghai. The corresponding prediction errors are reduced by about 47% for Wuhan and by 67% for Shanghai, which enables much more reliable AQI forecasts for both cities. [ABSTRACT FROM AUTHOR]

Honey bee decline is currently one of the world's most serious environmental issues, and scientists, governments, and producers have generated interest in understanding its causes and consequences in honey production and food supply. Mexico is one of the world's top honey producers, however, the honey bee population's status has not been documented to date. Based on 32 years of data from beekeeping, we make a country-level assessment of honey bee colony trends in Mexico. We use generalized additive mixed models to measure the associations between the percent change in honey bee hives and the percent change in honey yield per hive in relation to land-use, climate, and socioeconomic conditions. Despite the fact that the average annual yield per hive increased from 1980 to 2012, we detected a significant decline in the percent change in the number of honey bee hives across the time period studied. We also found a relationship between climatic conditions and agricultural land use, with agriculture increases and high temperatures producing a decrease in the percent change in honey yield. We found a relationship between a reduction in the temperature range (the difference between maximum and minimum temperatures) and a decrease in the percent change in the number of hives, while socioeconomic factors related to poverty levels have an impact on the number of hives and honey yields. Although long-term declines in hive numbers are not correlated with poverty levels, socioeconomic factors in states with high and medium poverty levels limit the increase in honey yield per hive. These results provide evidence that land-use changes, unfavorable climatic conditions, political, and socioeconomic factors are partially responsible for the reductions in the percent change in honey bee hives in Mexico. [ABSTRACT FROM AUTHOR]

To test the long-term efficacy of mammalian pest control, annual distance sampling estimates of the density of North Island kākā (Nestor meridionalis septentrionalis) within the southern Waipapa Ecological Area (WEA), Pureora Forest Park from 2008-2020 are compared to previously published estimates made at the same sites and time of year (October) between 2000-2007. Kākā density increased approximately four-fold from an average of c. 0.5 (95% CI 0.5-0.6) birds ha-1 between 2000 and 2007 to c. 2.3 (95% CI 1.9-2.8) birds ha-1 in 2020. The average of rate of increase between 2000 and 2018 was c. 6.9% per annum. Kākā recovery is likely to be a function of multiple mast events and long-term (> 20 years), large-scale, frequent, effective control of possums (Trichosurus vulpecula) and probably mustelids. It is recommended that the current pest control as well as kākā and pest monitoring continue. [ABSTRACT FROM AUTHOR]