Conserving threatened species requires taking a landscape or regional scale approach to maintain connectivity among populations. In a new study, Rodrigues and colleagues propose a framework for informing countrywide connectivity conservation for large carnivores, focusing on the endangered Asiatic wild dog in India.
Why conserve connectivity?
The increase in human footprint and rapid changes in land-use patterns threaten the existence of several endangered species. Recent studies have called for a shift from a population centric focus to a landscape or regional scale perspective to safeguard and facilitate connectivity among populations.
Connectivity at different scales can provide unique and complementary insights and inferences for conservation actions. These scales may be at the (1) range-wide or national-level to assess transboundary conservation interventions, (2) at the regional-level to identify metapopulations, connectivity corridors and potential source-sink populations, or (3) at smaller spatial scales such as the landscape-level to assist with spatial prioritization, corridor design and evaluating corridor functionality.
What scales should we consider?
Conservation interventions are often implemented based on political jurisdictions. Linking ecologically pertinent results to administrative units would therefore provide easier implementation of targeted conservation actions and strengthen ties between ecology and policy.
In our study, we present a framework for assessing connectivity conservation that links ecological and administrative scales, thereby optimising its relevance for practitioners. We first considered the countrywide scale to assess potential connectivity patterns across the country and to identify priority areas for transboundary conservation efforts. At the smaller regional scale, we delineated conservation landscapes informed through species ecology.
We then focused on Protected Areas or potential population sources to assess the degree of connectedness within each landscape. Lastly, at the smallest scale, we explored species’ accessibility to optimal habitats (proxy for resources) within landscapes, and overlaid administrative units to prioritise units in need of targeted conservation efforts.
India’s wild dogs as a case study
We applied this framework to the endangered Asiatic wild dog or ‘dhole’ in India. Countrywide connectivity was assessed among 155 potential source populations (Protected Areas). Dhole populations fell into three conservation landscapes– Western and Eastern Ghats (WEG), Central Indian Landscape (CIL) and North-East India (NEI)– exhibiting varying degrees of connectivity and anthropogenic threats.
Source population clusters within WEG were pivotal for maintaining connectivity across the landscape while populations across CIL and NEI had similar connectedness. Access to optimal habitats relied on PAs functioning as stepping stones and structural corridors between PAs. Finally, we identified 114 administrative units of priority for habitat consolidation to improve connectivity.
Our results show that populations from NEI are likely to benefit from international collaborations between India and other south Asian countries, namely, Nepal, Bhutan, China and Myanmar. We provide the first evidence for the link between Western and Eastern Ghats populations; although, populations within the Eastern Ghats appear to be largely limited to Protected Areas, and weakly connected to the landscape, overall. Our findings also suggest that connectivity conservation actions should be targeted in WEG due to its vulnerable (linear) spatial configuration, and in CIL because it has a lower proportion of areas under protection and needs functional corridors for connecting populations.
Our study achieved three key objectives– (1) the main results offer important insights on a relatively under-studied carnivore in a globally important region; (2) we show how incrementally building knowledge can benefit species that do not have a long history of targeted, systematic quantitative assessments; and (3) our framework, which uses open-source data, published information and freely-accessible software or code, can be applied to other under-studied species of conservation concern, particularly in the tropics and in global south countries.
Implementing evidence-based conservation interventions hinges on political will and administrative jurisdictions. Extending our approach to other regions and landscapes could contribute towards creating more comprehensive species conservation plans that explicitly incorporate connectivity considerations.
Read the full paper Dog in the matrix: Envisioning countrywide connectivity conservation for an endangered carnivore in Journal of Applied Ecology.