Privately protected areas provide key opportunities for the regional persistence of large‐ and medium‐sized mammals

The ecological drivers and consequences of wildlife trade

Wildlife trade is a key driver of extinction risk, affecting at least 24% of terrestrial vertebrates. The persistent removal of species can have profound impacts on species extinction risk and selection within populations. We draw together the first review of characteristics known to drive species use - identifying species with larger body sizes, greater abundance, increased rarity or certain morphological traits valued by consumers as being particularly prevalent in trade. We then review the ecological implications of this trade-driven selection, revealing direct effects of trade on natural selection and populations for traded species, which includes selection against desirable traits. Additionally, there exists a positive feedback loop between rarity and trade and depleted populations tend to have easy human access points, which can result in species being harvested to extinction and has the potential to alter source-sink dynamics. Wider cascading ecosystem repercussions from trade-induced declines include altered seed dispersal networks, trophic cascades, long-term compositional changes in plant communities, altered forest carbon stocks, and the introduction of harmful invasive species. Because it occurs across multiple scales with diverse drivers, wildlife trade requires multi-faceted conservation actions to maintain biodiversity and ecological function, including regulatory and enforcement approaches, bottom-up and community-based interventions, captive breeding or wildlife farming, and conservation translocations and trophic rewilding. We highlight three emergent research themes at the intersection of trade and community ecology: (1) functional impacts of trade; (2) altered provisioning of ecosystem services; and (3) prevalence of trade-dispersed diseases. Outside of the primary objective that exploitation is sustainable for traded species, we must urgently incorporate consideration of the broader consequences for other species and ecosystem processes when quantifying sustainability.

Troubled spots: Human impacts constrain the density of an apex predator inside protected areas

Effective conservation requires understanding the processes that determine population outcomes. Too often, we assume that protected areas conserve wild populations despite evidence that they frequently fail to do so. Without large-scale studies, however, we cannot determine what relationships are the product of localized conditions versus general patterns that inform conservation more broadly. Leopards' (Panthera pardus) basic ecology is well studied but little research has investigated anthropogenic effects on leopard density at broad scales. We investigated the drivers of leopard density among 27 diverse protected areas in northeastern South Africa to understand what conditions facilitate abundant populations. We formulated 10 working hypotheses that considered the relative influence of bottom-up biological factors and top-down anthropogenic factors on leopard density. Using camera-trap survey data, we fit a multi-session spatial capture-recapture model with inhomogenous density for each hypothesis and evaluated support using an information theoretic approach. The four supported hypotheses indicated that leopard density is primarily limited by human impacts, but that habitat suitability and management conditions also matter. The proportion of camera stations that recorded domestic animals, a proxy for the extent of human impacts and protected area effectiveness, was the only predictor variable present in all four supported models. Protected areas are the cornerstone of large felid conservation, but only when the human-wildlife interface is well managed and protected areas shelter wildlife populations from anthropogenic impacts. To ensure the long-term abundance of large carnivore populations, reserve managers should recognize the ineffectiveness of "paper parks" and promote contiguous networks of protected areas that offer leopards and other large mammal populations greater space and reduced human impacts.

Privately protected areas increase global protected area coverage and connectivity

Privately protected areas (PPAs) are increasing in number and extent. Yet, we know little about their contribution to conservation and how this compares to other forms of protected area (PA). We address this gap by assessing the contribution of 17,561 PPAs to the coverage, complementarity and connectivity of existing PA networks in 15 countries across 5 continents. We find that PPAs (1) are three times more likely to be in biomes with <10% of their area protected than are other PA governance types and twice as likely to be in areas with the greatest human disturbance; (2) that they protect a further 1.2% of key biodiversity areas; (3) that they account for 3.4% of land under protection; and (4) that they increase PA network connectivity by 7.05%. Our results demonstrate the unique and significant contributions that PPAs can make to the conservation estate and that PPAs deserve more attention, recognition and resources for better design and implementation.

Maintaining landholder satisfaction and management of private protected areas established under conservation agreements

Permanent protection of biodiversity on private lands is achieved through various mechanisms around the world. In Australia, conservation covenants are widely used to dedicate private lands to biodiversity conservation. The permanency of covenants necessitates similarly long-term commitment by landholders to meet and maintain the conservation obligations under the covenant. To better understand the effectiveness of conservation covenants as a tool for on-going environmental stewardship, we examined the relationship between landholders' initial motivations to covenant, their current perspectives on covenants and their management practices. We compared two groups of covenantors, those who initiated a covenant (original signees) and those who acquired a property with a covenant already in place (successive owners). We found the motivations and views of original signees and successive owners were similar overall, showing strong pro-environmental perspectives, and the majority of landholders were continuing to undertake management activities for the benefit of biodiversity. A small portion of respondents were dissatisfied with the covenant mechanism or covenant provider. This group tended to include successive owners and landholders who covenanted for regulatory reasons or financial incentives. Fewer dissatisfied landholders were actively managing the covenanted land compared to those who were satisfied. Considering the impending increase in successive owners as aging covenantors transfer ownership of their properties, the growing potential for covenants required under regulatory arrangements, and decreasing support within covenanting programs, this study identifies a risk that the satisfaction of landholders may decrease over time. Recognizing and addressing the challenges faced by landholders can bolster the commitment to covenant obligations and the longevity of covenants as a mechanism for positive conservation outcomes.

Privately Protected Areas: Missing Pieces of the Global Conservation Puzzle

Protected areas are an essential component of global conservation efforts. Although extensive information is available on the location of protected areas governed by governments, data on privately protected areas remain elusive at the global level. These are areas governed by private individuals and groups—ranging from families to religious institutions to companies—that meet IUCN's definition of a protected area: a clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values. As the world's governments prepare to adopt a new post-2020 global biodiversity framework to guide conservation over the next decade, we argue that, without complete data on privately protected areas, they do so without a vital piece of the puzzle.

Conservation and social outcomes of private protected areas

Government administered protected areas (PAs) have dominated conservation strategies, discourse, and research, yet private actors are increasingly managing land for conservation. Little is known about the social and environmental outcomes of these privately protected areas (PPAs). We searched the global literature in English on PPAs and their environmental and social outcomes and identified 412 articles suitable for inclusion. Research on PPAs was geographically skewed; more studies occurred in the United States. Environmental outcomes of PPAs were mostly positive (89%), but social outcomes of PPAs were reported less (12% of all studies), and these outcomes were more mixed (65% positive). Private protected areas increased the number or extent of ecosystems, ecoregions, or species covered by PAs (representativeness) and PA network connectivity and effectively reduced deforestation and restored degraded lands. Few PPA owners reported negative social outcomes, experienced improved social capital, increased property value, or a reduction in taxes. Local communities benefited from increased employment, training, and community-wide development (e.g., building of schools), but they reported reduced social capital and no significant difference to household income. The causal mechanisms through which PPAs influence social and environmental outcomes remain unclear, as does how political, economic, and social contexts shape these mechanisms. Future research should widen the geographical scope and diversify the types of PPAs studied and focus on determining the casual mechanisms through which PPA outcomes occur in different contexts. We propose an assessment framework that could be adopted to facilitate this process.

Benefits Beyond Borders: Assessing Landowner Willingness-to-Accept Incentives for Conservation Outside Protected Areas

Unplanned land-use change surrounding protected areas (PAs) can lead to degradation and fragmentation of wildlife habitats, thereby placing tremendous pressure on PAs especially in tropical countries. Incentivizing the expansion of habitats beyond PAs will not only benefit wildlife but also has the potential to create livelihood opportunities for marginalized communities living adjacent to PAs. Our study explored landowners’ willingness to participate in an incentive-based, wildlife-friendly land-use program using a discrete choice modeling approach. We surveyed 699 landowners living in 287 villages within a five-kilometer buffer around Nagarahole and Bandipur National Parks in India. We found that landowners preferred wildlife-friendly land-use over their ongoing farming practices. Landowners preferred short-term programs, requiring enrolling smaller parcels of land for wildlife-friendly land-use, and offering higher payment amounts. Landowners with larger landholdings, a longer history of living next to the PA, and growing fewer commercial crops were more likely to prefer enrolling large parcels of land. Landowners who grew more commercial crops were likely to prefer long term programs. We also estimated the average monetary incentive to be INR 64,000 (US$ 914) per acre per year. Wildlife-friendly land use, in developing economies like India with shrinking wildlife habitats and expanding infrastructural developments, could supplement rural incomes and potentially expand habitat for wildlife, thereby being a promising conservation strategy.

The biological, social, and political complexity of conserving oribi antelope Ourebia ourebi in South Africa

The endangered oribi antelope Ourebia ourebi is highly dependent on privately owned lands for its continued survival in South Africa. Despite the fact that conserving oribi may result in costs to farmers in the form of land use restrictions and pressures from illegal hunting, there is evidence that South African farmers are willing to conserve oribi on their lands. However, to date, no research has been conducted to examine farmers’ understanding of how to manage their lands for oribi or their motivations for conserving this species. We conducted 50 in-depth interviews with private landowners in KwaZulu-Natal, South Africa, to investigate why farmers are willing to protect oribi, their perceptions of the threats to the species, and their understanding of how land should be managed to benefit oribi. Respondents’ willingness to conserve oribi was driven primarily by an affinity for the species and wildlife in general. Respondents perceived illegal taxi hunting to be the greatest threat to oribi. Taxi hunts are organized, illegal hunting events that involve multiple participants and packs of dogs, who hunt at night on farms without the permission or knowledge of farmers. Although some respondents managed their lands specifically to benefit oribi, most were unsure which land management practices would support oribi conservation efforts. Farmers require legal support to more effectively conserve oribi. In addition, they would benefit from outreach and awareness programs on how to manage their lands for oribi.

Reference state and benchmark concepts for better biodiversity conservation in contemporary ecosystems

Measuring the status and trends of biodiversity is critical for making informed decisions about the conservation, management or restoration of species, habitats and ecosystems. Defining the reference state against which status and change are measured is essential. Typically, reference states describe historical conditions, yet historical conditions are challenging to quantify, may be difficult to falsify, and may no longer be an attainable target in a contemporary ecosystem. We have constructed a conceptual framework to help inform thinking and discussion around the philosophical underpinnings of reference states and guide their application. We characterize currently recognized historical reference states and describe them as Pre-Human, Indigenous Cultural, Pre-Intensification and Hybrid-Historical. We extend the conceptual framework to include contemporary reference states as an alternative theoretical perspective. The contemporary reference state framework is a major conceptual shift that focuses on current ecological patterns and identifies areas with higher biodiversity values relative to other locations within the same ecosystem, regardless of the disturbance history. We acknowledge that past processes play an essential role in driving contemporary patterns of diversity. The specific context for which we design the contemporary conceptual frame is underpinned by an overarching goal-to maximize biodiversity conservation and restoration outcomes in existing ecosystems. The contemporary reference state framework can account for the inherent differences in the diversity of biodiversity values (e.g. native species richness, habitat complexity) across spatial scales, communities and ecosystems. In contrast to historical reference states, contemporary references states are measurable and falsifiable. This 'road map of reference states' offers perspective needed to define and assess the status and trends in biodiversity and habitats. We demonstrate the contemporary reference state concept with an example from south-eastern Australia. Our framework provides a tractable way for policy-makers and practitioners to navigate biodiversity assessments to maximize conservation and restoration outcomes in contemporary ecosystems.

Cross-scale and social-ecological changes constitute main threats to private land conservation in South Africa

Conserving biodiversity in the long term will depend in part on the capacity of Protected Areas (PAs) to cope with cross-scale, social-ecological disturbances and changes, which are becoming more frequent in a highly connected world. Direct threats to biodiversity within PAs and their interactions with broader-scale threats are both likely to vary with PA spatial and management characteristics (e.g., location, dependence on ecotourism revenues, governmental support). Private Land Conservation Areas (PLCAs) are interesting case study systems for assessing cross-scale threats to PAs and their determinants. Despite the growing number of PLCAs around the world, there is considerable uncertainty regarding the long-term capacity of these privately owned areas to conserve biodiversity. Their potential impermanence is commonly raised as a key concern. To better understand the threats to which different types of PLCAs are likely to be vulnerable, we asked 112 PLCA landholders in South Africa what they perceived as the top threats to their PLCAs. Landowners identified direct threats to the biodiversity within their PLCAs (e.g., poaching, extreme weather, inappropriate fire regimes, alien species) as well as describing broader socio-economic threats (e.g., regional crime, national legislation and politics, global economic recessions), which were noted to interact across scales. We found support for the hypothesis that patterns in the perceived multi-scale threats to a PLCA correspond with its management and spatial characteristics, including its remoteness, dependence on ecotourism or hunting revenues, and richness of megafaunal species. Understanding the threats to which different PLCAs may be vulnerable is useful for developing more nuanced, targeted strategies to build PLCA resilience to these threats (for example, by strengthening the capacity of self-funded PLCAs to cope with the threat of economic downturns through more innovative financial instruments or diversified revenue streams). Our findings highlight the importance of considering interactions between broad-scale socio-economic changes and direct threats to biodiversity, which can influence the resilience of PAs in ways that are not anticipated by more traditional, discipline-specific consideration of direct threats to the biodiversity within their boundaries.

Coexistence between wildlife and livestock is contingent on cattle density and season but not differences in body size

Many studies on the coexistence of wildlife with livestock have focused primarily on similar-sized species. Furthermore, many of these studies have used dietary overlap as a measure of potential competition between interacting species and thus lack the important link between dietary overlap and any negative effects on a particular species–a prerequisite for competition. Consequently, the mechanisms that drive interspecific interactions between wildlife and cattle are frequently overlooked. To address this, we used an experimental setup where we leveraged different cattle stocking rates across two seasons to identify the drivers of interspecific interactions (i.e. competition and facilitation) between smaller-bodied oribi antelope and cattle. Using direct foraging observations, we assessed dietary overlap and grass regrowth, and also calculated oribi nutritional intake rates. Ultimately, we found that cattle compete with, and facilitate, smaller-bodied oribi antelope through bottom-up control. Specifically, cattle facilitated oribi during the wet season, irrespective of cattle stocking density, because cattle foraging produced high-quality grass regrowth. In contrast, during the dry season, cattle and oribi did not co-exist in the same areas (i.e. no direct dietary overlap). Despite this, we found that cattle foraging at high densities during the previous wet season reduced the dry season availability of oribi’s preferred grass species. To compensate, oribi expanded their dry season diet breadth and included less palatable grass species, ultimately reducing their nutritional intake rates. Thus, cattle competed with oribi through a delayed, across-season habitat modification. We show that differences in body size alone may not be able to offset competitive interactions between cattle and wildlife. Finally, understanding the mechanisms that drive facilitation and competition are key to promoting co-existence between cattle and wildlife.