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Surface freshwater is a vital resource that is declining globally, predominantly due to climate and land use changes. Cambodia is no exception and the loss threatens many species, such as the giant ibis a Critically Endangered waterbird. We aimed to quantify the spatial and temporal (2000–2020) change of surface water availability across northern and eastern Cambodia and to assess the impact of this on the giant ibis. We used a Random Forest Classifier to determine the changes and we tested the impact of land use and geographical covariates using spatially explicit regression models. We found an overall reduction of surface water availability of 4.16%. This was predominantly driven by the presence of Economic Land Concessions and roads which increased the probability of extreme drying and flooding events. The presence of protected areas reduced these probabilities. We found changes in precipitation patterns over the wider landscape did not correlate with changes in surface water availability, supporting the overriding influence of land use change. 98% of giant ibis nests recorded during the time period were found within 25m of surface water during the dry season, highlighting their dependency on surface water. The overall surface water decline resulted in a 25% reduction in dry season suitable habitat for the giant ibis. Although absolute changes in surface water over the whole area were relatively small, the impact on the highest quality habitat for ibis is disproportionate and therefore threatens its populations. Defining the threats to such an endangered species is crucial for effective management. [ABSTRACT FROM AUTHOR]

Protected areas have been gazetted to protect natural resources and biodiversity, but evaluations of effectiveness rarely include measures of species population change. We compiled annual site‐level spending and elephant population data for 102 protected areas conserving either savannah (Loxodonta africana) or forest (Loxodonta cyclotis) elephants, which showed a median annual population decline of −0.78% across the protected areas. Site‐level population change was strongly associated with funding and government effectiveness. Annual funding deficits occurred in 78% of the protected areas, and when comparing necessary levels of annual spend to stabilize elephant populations, we estimate a US$1.5 billion annual funding deficit across all the protected areas. While financial investment can improve elephant conservation outcomes, there is still a need to identify where and how to best finance elephant poaching interventions, requiring a global commitment to improve the socioeconomic impacts of protected areas on local communities and reduce ivory demand. [ABSTRACT FROM AUTHOR]

While global patterns of bee diversity have been modelled, our understanding of fine‐scale regional patterns is more limited, particularly for under‐sampled regions such as Africa. South Africa is among the exceptions on the African continent; its bee fauna (ca. 1253 species) has been well collected and documented, including mass digitising of its natural history collections. It is a region with high floral diversity, high habitat heterogeneity and variable rainfall seasonality.Here, we combine a South African bee species distributional database (877 bee species) with a geospatial modelling approach to determine fine‐scale (~11 × 11 km grid cell resolution) hotspots of bee species richness, endemism and range‐restricted species.Our analyses, based on the probabilities of occurrence surfaces for each species across 108,803 two‐minute grid cells, reveal three bee hotspots of richness: Winter rainfall, Aseasonal rainfall and Early‐to‐late summer rainfall. These hotspots contain large numbers of endemic and geographically restricted taxa. Hotspots with particularly high bee diversity include the Fynbos, Succulent Karoo and Desert biomes; the latter showing 6–20 times more species per unit area than other biomes. Our results conform with global species‐area patterns: areas of higher‐than‐expected bee density are largely concentrated in Mediterranean and arid habitats.This study further enhances our knowledge in identifying regional and global hotspots of richness and endemism for a keystone group of insects and enabling these to be accounted for when setting conservation priorities. [ABSTRACT FROM AUTHOR]

Tropical montane insects are vulnerable to climate change if up‐hill range retractions reduce range sizes and increase extinction risk. Endemic species will be particularly at risk if they disproportionately occur at higher elevations, although threats may be ameliorated if they have morphological traits associated with improved thermoregulatory ability. We examine the vulnerability of endemic swallowtail butterflies on Sulawesi (Indonesia) to climate change by quantifying inter‐specific variation in traits associated with thermoregulation (body size and melanism) and whether species' traits are associated with the elevation of species' ranges. We collected data on size, melanism and elevation of 29 swallowtail butterfly species (Lepidoptera: Papilionidae) from 754 specimens at the Natural History Museum (United Kingdom) and the Zoologische Staatssammlung München (Germany). Endemic butterflies were less melanised (16 endemic species, mean = 83% melanised; 13 non‐endemic species = 89% melanised) but similar to non‐endemics in size (endemic, mean = 56 mm; non‐endemic = 53 mm) and elevation (endemic, mean = 345 m.a.s.l.; non‐endemic: 291 m). There was no evidence that species size or melanism patterns were related to elevation in either group. Few differences in elevation of endemic and non‐endemic species imply that endemic swallowtail butterflies are not disproportionately more threatened by climate‐driven mountaintop extirpation than non‐endemic species. Further work is needed to examine whether paler wings alter the ability of endemic species to thermoregulate and adapt to changing climates. In the absence of reductions in anthropogenic global greenhouse gas emissions, on‐going climate warming will continue to threaten tropical montane species. [ABSTRACT FROM AUTHOR]

Aim: Climate change and habitat loss or degradation are some of the greatest threats that species face today, often resulting in range shifts. Species traits have been discussed as important predictors of range shifts, with the identification of general trends being of great interest to conservation efforts. However, studies reviewing relationships between traits and range shifts have questioned the existence of such generalized trends, due to mixed results and weak correlations, as well as analytical shortcomings. The aim of this study was to test this relationship empirically, using analytical approaches that account for common sources of bias when assessing range trends. Location: Tanzania, East Africa. Time period: 1980–1999 and 2000–2020. Major taxa studied: 57 savannah specialist birds found in Tanzania, belonging to 26 families and 11 orders. Methods: We applied recently developed integrated spatio‐temporal species distribution models in R‐INLA, combining citizen science and bird Atlas data to estimate ranges of species, quantify range shifts, and test the predictive power of traditional trait groups, as well as exposure‐related and sensitivity traits. We based our study on 40 years of bird observations in East African savannahs, a biome that has experienced increasing climatic and non‐climatic pressures over recent decades. We correlated patterns of change with species traits using linear regression models. Results: We find indications of relationships identified by previous research, but low average explanatory power of traits from an ecological perspective, confirming the lack of meaningful general associations. However, our analysis finds compelling species‐specific results. Main conclusions: We highlight the importance of individual assessments while demonstrating the usefulness of our analytical approach for analyses of range shifts. [ABSTRACT FROM AUTHOR]

Aim: Humans have altered ecosystem productivity and biodiversity worldwide by changing land‐cover types and management. High local species richness is commonly found in geographic areas and ecosystems with high net primary productivity (NPP), but the long‐term effects of modification on productivity and biodiversity change, and particularly on the relationship between the two, are poorly understood. Here we evaluate whether human modification tends to increase biodiversity in low‐productivity ecosystems (where human management is likely to increase productivity) and decrease biodiversity in ecosystems that were originally high‐productive. Location: Global. Time Period: 2001–2013. Major Taxa Studied: Plants, mammals, birds, hexapods, arachnids, other terrestrial invertebrates, amphibians, reptiles and fungi. Methods: We assembled a large worldwide dataset of NPP and associated species richness from MODIS land cover and NPP products and the PREDICTS biodiversity database, involving 11,849 sites. This enabled comparisons of species richness and NPP differences between samples of relatively natural and human‐modified vegetation within the same geographic regions, considering 102 types of land‐cover transitions. Results: (1) Modification from non‐forest vegetation to forests on average increased NPP by 7.76%, and vice versa. (2) Human modification of less productive areas tended to increase NPP and vice versa, with stronger effects of major modification. (3) However, site‐level species richness decreases were associated with nearly all land‐cover transitions from relatively natural to modified vegetation. (4) Despite expectations, we found no significant relationship between species richness differences (between relatively natural and modified vegetation) and productivity differences, when considering conversions across land‐cover types and excluding human‐appropriated productivity in croplands. Main Conclusions: Human modification tends to increase NPP in low‐productivity ecosystems, but species richness declines are associated with most major human‐induced land‐cover changes. Therefore, increasing or decreasing NPP did not generate corresponding increases or decreases in species richness, contrary to expectations of the general species richness‐productivity relationship. [ABSTRACT FROM AUTHOR]

Measuring the impacts of anthropogenic activities on wildlife is crucial for ensuring effective management. Animal behavior is often considered a sensitive index of impact, but its use requires detailed understanding of the context dependent decisions animals make. In this manuscript I identify a number of areas where insights from the field of animal behavior are relevant to studies of human disturbance and activity. In particular, I differentiate between disturbance effects and disturbance impacts and show how context-dependent decision-making often makes animal behavior an unreliable index of impact. I show the areas where animal behavior can be useful in quantifying minimum disturbance impact when additional information is available, and identify a number of areas where further research may help improve the management of anthropogenic activities within wildlife areas.

This paper could not have been written without the financial and organizational support from Dieter Paulmann and Jo Hastie respectively. Thanks are also due to two anonymous reviewers, whose comments on an earlier version of the manuscript greatly improved the paper. The views expressed in this paper are those of the authors alone and do not represent those of Stellwagen Bank National Marine Sanctuary, the U.S. National Marine Sanctuary Program, Southwest Fisheries Science Center, the U.S. National Marine Fisheries Service, NOAA and/or any other institution or agency. Correspondence concerning this article should be addressed to Andrew Wright, Leviathan Sciences, U.S.A. (marinebrit@gmail.com). Sound travels much further than light in the marine environment. As a result, marine mammals, especially cetaceans, rely heavily on sound for many important life functions, including breeding and foraging. This reliance on sound means it is quite likely that exposure to noise will have some detrimental effects on these life functions. However, there has been little application to marine mammals of the knowledge available in other species of stress responses to noise and other stressors. In this paper we begin to integrate what is known about marine mammals with the current knowledge gained in terrestrial mammals about stress physiology, specifically considering physiological and psychological context and thus also cumulative and synergistic impacts. We determined that it is reasonable to extrapolate information regarding stress responses in other species to marine mammals, because these responses are highly conserved among all species in which they have been examined to date. As a result, we determined that noise acts as a stressor to marine mammals. Furthermore, given that marine mammals will likely respond in a manner consistent with other species studied, repeated and prolonged exposures to stressors (including or induced by noise) will be problematic for marine mammals of all ages. A range of issues may arise from the extended stress response including, but not limited to, suppression of reproduction (physiologically and behaviorally), accelerated aging and sickness-like symptoms. We also determined that interpretation of a reduction in behavioral responses to noise as acclimation will be a mistake in many situations, as alternative reasons for the observed results are much more likely. We recommend that research be conducted on both stress responses and life-history consequences of noise exposure in marine mammals, while emphasizing that very careful study designs will be required. We also recommend that managers incorporate the findings presented here in decisions regarding activities that expose marine mammals to noise. In particular, the effects of cumulative and synergistic responses to stressors can be very important and should not be dismissed lightly.

This paper could not have been written without the financial and organizational support from Dieter Paulmann and Jo Hastie respectively. Thanks are also due to 2 anonymous reviewers, whose comments on an earlier version of the manuscript greatly improved the paper. The views expressed in this paper are those of the authors alone and do not represent those of Stellwagen Bank National Marine Sanctuary, the U.S. National Marine Sanctuary Program, Southwest Fisheries Science Center, the U.S. National Marine Fisheries Service, NOAA and/or any other institution or agency. Correspondence concerning this article should be addressed to Andrew Wright, Leviathan Sciences, U.S.A. (marinebrit@gmail.com). Consequences of extreme noise exposure are obvious and usually taken into some consideration in the management of many human activities that affect either human or animal populations. However, the more subtle effects such as masking, annoyance and changes in behavior are often overlooked, especially in animals, because these subtleties can be very difficult to detect. To better understand the possible consequences of exposure to noise, this review draws from the available information on human and animal physiology and psychology, and addresses the importance of context (including physiological and psychological state resulting from any previous stressor exposure) in assessing the true meaning of behavioral responses. The current consensus is that the physiological responses to stressors of various natures are fairly stereotyped across the range of species studied. It is thus expected that exposure to noise can also lead to a physiological stress response in other species either directly or indirectly through annoyance, a secondary stressor. In fact many consequences of exposure to noise can result in a cascade of secondary stressors such as increasing the ambiguity in received signals or causing animals to leave a resourceful area, all with potential negative if not disastrous consequences. The context in which stressors are presented was found to be important not only in affecting behavioral responses, but also in affecting the physiological and psychological responses. Young animals may be particularly sensitive to stressors for a number of reasons including the sensitivity of their still-developing brains. Additionally, short exposure to stressors may result in long-term consequences. Furthermore, physiological acclimation to noise exposure cannot be determined from apparent behavioral reactions alone due to contextual influence, and negative impacts may persist or increase as a consequence of such behavioral changes. Despite the lack of information available to managers, uncertainty analysis and modeling tools can be coupled with adaptive management strategies to support decision making and continuous improvements to managing the impacts of noise on free-ranging animals.

We consider pairs of spatial point processes with intensity functions sharing a common multiplicative term. We introduce two novel approaches to estimating the pair correlation function for one of the point processes by treating the other as a baseline so as to account for the unspecified part of the intensity functions. The first approach is based on nonparametric kernel-smoothing, whereas the second approach uses a conditional likelihood estimation approach to fit a parametric model for the pair correlation function. A great advantage of the proposed methods is that they do not require the often difficult estimation of the unspecified part of the intensity functions. We establish the consistency of the resulting estimators and discuss how the parametric estimator can be applied in model diagnostics and inference on regression parameters for the intensity functions. We apply the proposed procedures to two spatial point patterns regarding the spatial distributions of birds in the U.K.'s Peak District in 1990 and 2004. KEY WORDS: Conditional likelihood; Inhomogeneous spatial point process; Pair correlation function; Proportional intensity functions; Residual diagnostics.