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1. Farmland ponds are a highly threatened freshwater habitat which has undergone dramatic losses during the last 200 years due to land drainage schemes and agricultural intensification. Agri-environment schemes (AES) incentivize farmers to adopt farming methods to benefit biodiversity, yet there are a paucity of data evaluating the success of artificially created AES ponds as analogues of natural ponds in an attempt to recreate lost environments. 2. We examined variation in environmental parameters and aquatic and terrestrial invertebrate communities between 38 natural ponds and 91 artificial ponds that were created in southwest Ireland (n = 129). 3. Artificial ponds in agricultural grassland did not replicate natural ponds in adjacent semi-natural habitats differing significantly in size, pH, conductivity, productivity (indicated by submerged and emergent plant cover including algae) and surrounding vegetation structure that is, sward height. These differences significantly influenced aquatic and terrestrial invertebrate community structure with a suite of indicator taxa in both natural and artificial ponds. 4. The conservation value of artificial ponds in agricultural grasslands should not be underestimated as they had 43% higher aquatic species richness and 33% higher aquatic species abundance than natural ponds in adjacent semi-natural habitats. 5. Synthesis and applications. We demonstrate that artificial agri-environment scheme ponds created in agricultural grasslands, whilst not direct analogues of natural ponds in adjacent semi-natural habitats, do fulfil a role in preserving high local biodiversity albeit representing a different community of species. Creation of ponds in farmland as well as in adjacent natural habitats could provide a wider range of environmental conditions and richer associated macroinvertebrate communities, increasing landscape connectivity and further enhancing regional biodiversity. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Molecular methods can play a crucial role in species management and conservation. Despite the usefulness of genetic approaches, they are often not explicitly included as part of species recovery plans and conservation practises. The Natterjack toad (Epidalea calamita) is regionally Red-Listed as Endangered in Ireland. The species is declining and is now present at just seven sites within a highly restricted range. This study used 13 highly polymorphic microsatellite markers to analyse the population genetic diversity and structure. Genetic diversity was high with expected heterozygosity between 0.55 and 0.61 and allelic richness between 4.77 and 5.92. Effective population sizes were small (Ne < 100 individuals), but not abnormal for pond breeding amphibians. However, there was no evidence of historical or contemporary genetic bottlenecks or high levels of inbreeding. We identified a positive relationship between Ne and breeding pond surface area, suggesting that environmental factors are a key determinant of population size. Significant genetic structuring was detected throughout the species’ range, and we identified four genetic entities that should be considered in the species’ conservation strategies. Management should focus on preventing further population declines and future loss of genetic diversity overall and within genetic entities while maintaining adequate local effective population size through site-specific protection, human-mediated translocations and head-start programs. The apparent high levels of genetic variation give hope for the conservation of Ireland’s rarest amphibian if appropriately protected and managed.

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This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.