Peer-reviewed publications

Allocating resources to growth and reproduction requires grazers to invest time in foraging, but foraging promotes dental senescence and constrains expression of proactive antipredator behaviors such as vigilance. We explored the relationship between carnivore prey selection and prey foraging effort using incisors collected from the kills of coursing and stalking carnivores. We predicted that prey investing less effort in foraging would be killed more frequently by coursers, predators that often exploit physical deficiencies. However, such prey could expect delayed dental senescence. We predicted that individuals investing more effort in foraging would be killed more frequently by stalkers, predators that often exploit behavioral vulnerabilities. Further these prey could expect earlier dental senescence. We tested these predictions by comparing variation in age-corrected tooth wear, a proxy of cumulative foraging effort, in adult (3.4-11.9 years) wildebeest killed by coursing and stalking carnivores. Predator type was a strong predictor of age-corrected tooth wear within each gender. We found greater foraging effort and earlier expected dental senescence, equivalent to 2.6 additional years of foraging, in female wildebeest killed by stalkers than in females killed by coursers. However, male wildebeest showed the opposite pattern with the equivalent of 2.4 years of additional tooth wear in males killed by coursers as compared to those killed by stalkers. Sex-specific variation in the effects of foraging effort on vulnerability was unexpected and suggests that behavioral and physical aspects of vulnerability may not be subject to the same selective pressures across genders in multipredator landscapes.

Deforestation and forest fragmentation are leading drivers of biodiversity loss. Protected areas have been the leading conservation policy response, yet their scale and scope remain inadequate to meet biodiversity conservation targets. Managed forest concessions increasingly have been recognized as a complement to protected areas in meeting conservation targets. Similarly, programs for voluntary third-party certification of concession management aim to create incentives for logging companies to manage forests more sustainably. Rigorous evidence on the impacts from large-scale certification programs is thereby critical, yet detailed field observations are limited, temporally and spatially. Remotely-sensed data, in contrast, can provide repeated observations over time and at a fine spatial scale, albeit with less detail.

The global palm oil value chain has grown in complexity; stakeholder relationships and linkages are increasingly shaped by new public and private standards that aim to ameliorate social and environmental costs while harnessing economic gains. Regulatory initiatives in the emerging policy regime complex struggle to resolve sector-wide structural performance issues: pervasive land conflicts, yield differences between companies and smallholders, and carbon emissions arising from deforestation and peatland conversion. Identifying opportunities for more effective governance of the palm oil value chain and supply landscapes, this paper explores disconnects, complementarities, and antagonisms between public regulations and private standards, looking at the global, national, and subnational policy domains shaping chain actors' conduct. Greater complementarities have emerged among transnational instruments, but state regulation disconnects persist and antagonisms prevail between national state regulations and transnational private standards. Emerging experimental approaches, particularly at subnational level, aim to improve coordination to both enhance complementarities and resolve disconnects.

Species prioritization efforts are a common strategy implemented to efficiently and effectively apply conservation efforts and allocate resources to address global declines in biodiversity. These structured processes help identify species that best represent the entire species community; however, these methods are often subjective and focus on a limited number of species characteristics. We developed an objective, transparent approach using a Structured Decision Making (SDM) framework to identify a group of grassland bird species on which to focus conservation efforts that considers biological, social, and logistical criteria in the Northern Great Plains of North America. The process quantified these criteria to ensure representation of a variety of species and habitats and included the relative value of each criterion to the working group. These SDM methods provide a unique roadmap for prioritization of grassland bird species and offer an objective, transparent, and repeatable method of selection for priority species in other well-studied ecosystems.

Global pressures on freshwater ecosystems are high and rising. Viewed primarily as a resource for humans, current practices of water use have led to catastrophic declines in freshwater species and the degradation of freshwater ecosystems, including their genetic and functional diversity. Approximately three-quarters of the world's inland wetlands have been lost, one-third of the 28,000 freshwater species assessed for the International Union for Conservation of Nature (IUCN) Red List are threatened with extinction, and freshwater vertebrate populations are undergoing declines that are more rapid than those of terrestrial and marine species. This global loss continues unchecked, despite the importance of freshwater ecosystems as a source of clean water, food, livelihoods, recreation, and inspiration.

Climate change has significant consequences for land conservation. Government agencies and nonprofit land trusts heavily rely on perpetual conservation easements. However, climate change and other dynamic landscape changes raise questions about the effectiveness and adaptability of permanent conservation instruments like conservation easements. Building upon a study of 269 conservation easements and interviews with seventy conservation-easement professionals in six different states, we ex-amine the adaptability of conservation easements to climate change. We outline four potential approaches to enhance conservation outcomes under climate change: shift land-acquisition priorities to account for potential climate change impacts; consider conservation tools other than perpetual conservation easements; ensure that the terms of conservation easements permit the holder to adapt to climate change successfully; and provide for more active stewardship of conservation lands. There is still a good deal of uncertainty as to the legal fate of a conservation easement that no longer meets its original purposes. Many state laws provide that conservation easements can be modified or terminated in the same manner as traditional easements. Yet conservation easements are in many ways unlike other easements. The beneficiary is usually the public, not merely a neighboring landowner, and the holder is always a nonprofit conservation organization or a government agency. Thus, there is a case to be made for adaptive protection. An overly narrow focus on perpetual property rights could actually thwart efforts to meet adaptation needs over the long term. We call for careful attention to ensuring conservation outcomes in dynamic landscapes over time.

Increasing interest in measuring, modelling and valuing ecosystem services (ES), the benefits that ecosystems provide to people, has resulted in the development of an array of ES assessment tools in recent years. Selecting an appropriate tool for measuring and modelling ES can be challenging. This document provides guidance for practitioners on existing tools that can be applied to measure or model ES provided by important sites for biodiversity and nature conservation, including Key Biodiversity Areas (KBAs), natural World Heritage sites (WHS), and protected areas (PAs). Selecting an appropriate tool requires identifying the specific question being addressed, what sorts of results or outputs are required, and consideration of practical factors such as the level of expertise, time and data required for applying any given tool. This guide builds on existing reviews of ES assessment tools, but has an explicit focus on assessing ES for sites of importance for biodiversity and nature conservation.

In the decade since the Brisbane Declaration (2007) called upon governments and other decision makers to integrate environmental flows into water management, practitioners have continued to seek ways to expand implementation of flow restoration or protection. The science and practice of environmental flow assessment have evolved accordingly, generating diverse methods of differing complexity from which water managers or regulators need to select an approach best fitting their context. Uncertainty over method choice remains one of several of the more readily overcome barriers that have contributed to slowing the implementation of environmental flows. In this paper, we introduce a three-level framework intended to help overcome such barriers by intertwining holistic environmental flow assessment with implementation. The three levels differ based on the availability of resources and level of resolution required in the flow recommendations, with the framework designed to guide the user toward implementation at any level as soon as possible, based on at least some of the recommendations. Level 1 is a desktop analysis based on existing data, typically conducted by one or a few scientists. Level 2 is similarly mostly reliant on existing information, but brings together a multidisciplinary set of experts within a facilitated workshop setting to use both this knowledge and professional judgment to develop flow recommendations and fill data gaps. The most comprehensive assessment level, Level 3, guides the collection of new data and/or construction of models to test hypotheses developed by the expert team. Key characteristics of this framework include: (1) methods are matched to the levels of resources available and certainty required; funds for research are invested strategically to address critical knowledge gaps and thereby reduce uncertainty; (2) the framework is iterative and information generated at one level provides the foundation for, and identifies the need for, higher levels and; and (3) processes for flow assessment and implementation are intertwined, meaning they move forward in coordinated fashion, with each process informing the other. Using practical cases from North America, we illustrate how environmental flow assessment at each level has led to implementation, with changes in policy or management.

The Nationally Determined Contributions (NDCs) submitted under the Paris Agreement propose a country's contribution to global mitigation efforts and domestic adaptation initiatives. This paper provides a systematic analysis of NDCs submitted by South Asian nations, in order to assess how far their commitments might deliver meaningful contributions to the global 2°C target and to sustainable broad-based adaptation benefits. Though agriculture-related emissions are prominent in emission profiles of South Asian countries, their emission reduction commitments are less likely to include agriculture, partly because of a concern over food security.

Analysis of long-term trends in forest carbon stocks is challenged by interactions among climate change, wildfire and other disturbances, forest management actions, and heterogeneous vegetation responses. For such circumstances where complex interactions make it difficult to encompass the full range of processes in any one mode of analysis, expert elicitation is a well-developed method for documenting judgments about uncertainty, based on available evidence, to inform ongoing decision-making. Applying this method for the Sierra Nevada, we evaluate subjective probabilistic estimates of trends in aboveground forest carbon for different management scenarios toward the goal of maximizing carbon stored, while also considering implications for wildfire risk. The analysis examines the effects of four treatments in isolation (thinning, timber harvesting, prescribed burning, managed wildfire), as well as a user-defined management portfolio allocating resources across five management practices (thinning, harvesting, prescribed burning, firefighting, and restoration). The expert elicitation suggests that aboveground forest carbon stocks will decline 8%, from 126 to 116 tC/ha, between 2030 and 2100 (median estimate across experts) assuming conventional forest management practices are continued. Out of all surveyed practices, the custom user-defined management portfolio results in the highest carbon stock of 129 tC/ha which is 11% higher than conventional practice in 2100 at the 50th percentile. The expert elicitation indicates less beneficial carbon sequestration outcomes than recent modeling studies. Suggesting co-benefits across objectives, 75 experts collectively estimate a 61% likelihood that managing for carbon also reduces wildfire risk. By contrast, decreases in carbon stocks are anticipated for large magnitudes of climate change or substantial decreases in forest management investments.