Drilling Down Hotspots of Intraspecific Diversity to Bring Them Into On-Ground Conservation of Threatened Species

Abstract

Unprecedented rates of biodiversity loss raise the urgency for preserving species ability to cope with ongoing global changes. An approach in this direction is to target intra-specific hotspots of genetic diversity as conservation priorities. However, these hotspots are often identified by sampling at a spatial resolution too coarse to be useful in practical management of threatened species, hindering the long-appealed dialog between conservation stakeholders and conservation genetic researchers. Here, we investigated the spatial and temporal variation in species presence, genetic diversity, as well as potential risk factors, within a previously identified hotspot of genetic diversity for the endangered Apennine yellow-bellied toad Bombina pachypus. Our results show that this hotspot is neither a geographically homogeneous nor a temporally stable unit. Over a time-window spanning 10-40 years since previous assessments, B. pachypus populations declined in large portions of their hotspot, and their genetic diversity levels decreased. Considering the demographic trend, genetic and epidemiological data, and models of current and future climatic suitability, populations at the extreme south of the hotspot area still qualify for urgent in-situ conservation actions, whereas northern populations would be better managed through a mix of in-situ and ex-situ actions. Our results emphasize that identifying hotspots of genetic diversity, albeit an essential step, does not suffice to warrant on-ground conservation of threatened species. Hotspots should be analyzed at finer geographic and temporal scales, to provide conservation stakeholders with key knowledge to best define conservation priorities, and to optimize resource allocation to alternative management practices.

Distribution and conservation status of threatened endemic amphibians within the Aspromonte mountain region, a hotspot of Mediterranean biodiversity

“…It is worth noting that the unavailability of exact locations from previous surveys does not allow for direct comparison and inferences on population trends. However, we visited 26 known historical sites for B. pachypus (see Zampiglia et al 2019) and in 14 of them (54%), the presence of the species was not confirmed. A negative trend was also reported by local people (shepherds, farmers, woodcutters, and walkers), who confirmed that B. pachypus is less widespread now compared to the early 1990s when it was ubiquitous and abundant in hilly and mountain streams and ponds, as well as in artificial aquatic environments used for agriculture and local pastoralism.…”

“…Climatic and orographic diversification have generated ecological gradients and highly heterogeneous vegetation typologies (Spampinato et al 2008). In endemism, relict species, and ancient woods, the Aspromonte represents a hotspot of plant and animal biodiversity at the species, genetic, and community levels (Spampinato et al 2008;Zampiglia et al 2019;Piovesan et al 2020). Biodiversity conservation within the Aspromonte region is undertaken by the Aspromonte National Park (ANP), together with 57 Natura 2000 areas, 55 of which are Special Areas of Conservation (SACs) and two are Special Protection Areas (SPAs).…”

“…Despite the biogeographic and conservation value of this area, surveys on the distribution and conservation status of amphibians are scarce and discontinuous over space and time (Tripepi et al 1999;Tripepi and Sperone 2007;Temi and Agristudio 2018). The only exhaustive study carried out in this area to clarify the conservation status of an endangered amphibian, the Apennine Yellow-bellied toad, highlighted the strong discordance between the historical and current distribution of the investigated species (Zampiglia et al 2019). This evidence, coupled with the scarcity of data for other threatened amphibians, suggests the need for a thorough investigation of the current distribution of amphibians in this area.…”

Shock or jump: deimatic behaviour is repeatable and polymorphic in a yellow-bellied toad

“…We collected adult males from close but distinct ponds to ensure similar environmental conditions and predators, and to avoid collecting related individuals. Also, we selected this population because it has not been affected by either recent and historical decline, and all the individuals can be considered belonging to a unique and panmittic population [29]. Details about the study species, sampling and housing procedures are provided as Supplementary material.…”

Evidence for multiple refugia and hotspots of genetic diversity for Westralunio carteri, a threatened freshwater mussel in south‐western Australia

“…In this scenario, hotspots are 'melting pots' generated by (a) localized contraction and divergence of these populations and (b) subsequent admixture during re-expansion (Canestrelli et al, 2010). Under this model, priority areas for conservation might exist within the broader refugia; however, the spatial resolution of many phylogeographic studies is too coarse to pinpoint these areas and allow targeted allocation of resources (Zampiglia et al, 2019).…”