The use of local ecological knowledge (LEK) has been advocated for biodiversity monitoring and management. To date, however, it has been underused in studying wild populations of animals and, particularly, in obtaining quantitative abundance estimates. We evaluated LEK as a tool for collecting extensive data on local animal abundance and population trends. We interviewed shepherds in southeastern Spain, asking them to estimate the local abundance of the terrestrial tortoise Testudo graeca. We quantified reliability of abundance estimates derived from interviews by comparing them with those obtained from standard field-sampling protocols (distance sampling). We also explored the complementarity of these 2 approaches. LEK provided high-quality and low-cost information about both distribution and abundance of T. graeca. Interviews with shepherds yielded abundance estimates in a much wider range than linear transects, which only detected the species in the upper two-thirds of its abundance range. Abundance estimates from both methodologies showed a close relationship. Analysis of confidence intervals indicated local knowledge could be used to estimate mean local abundances and to detect mean population trends. A cost analysis determined that the information derived from LEK was 100 times cheaper than that obtained through linear-transect surveys. Our results should further the use of LEK as a standard tool for sampling the quantitative abundance of a great variety of taxa, particularly when population densities are low and traditional sampling methods are expensive or difficult to implement.

Should a species be translocated? Uncertainty regarding the necessity and feasibility of many translocations complicates answering this question. Here, we review translocation projects, both published and unpublished. Our results indicate that most projects (1) addressed fewer than half of the basic criteria established for translocations and (2) were either unjustifiable from a conservation perspective or inadequately designed to guarantee success or preclude negative consequences. We propose a hierarchical decision‐making system – an explicit method that integrates existing guidelines, thereby covering a key gap in conservation science – to reduce ambiguity when deciding whether to implement a given translocation project. This method will improve the likelihood of success in translocation projects and contribute to the efficient use of the limited resources available for these conservation efforts.

Abstract. The growth of inter-basin water transfers and the development of new irrigation facilities in southeastern Spain are responsible for a variety of ecological impacts. In spite of this, the construction of artificial ponds to keep water for intensive agriculture may also provide new habitats for breeding waterbirds. We counted waterbirds during the breeding season in artificial ponds that had been built up using different materials and measured their abiotic and biotic attributes. We found that ponds were used as breeding and foraging habitat by 22 different waterbird species and breeding numbers of a few of them seemed to be larger in these artificial facilities than in nearby natural and semi-natural wetlands. Abundance and richness of breeding waterbirds was influenced by construction materials. Ponds constructed with low density polyethylene and covered with sand and stones held more species and their numbers were higher than those constructed with other plastic materials. The presence of emergent and submerged vegetation as well as abiotic attributes, such as pond size, accounted for most of the deviance when modelling richness and species abundance.

This work represents the first attempt to model the habitat‐species relationships of a species of terrestrial tortoise on a large scale. We applied hierarchical variance partition methodology to Generalised Lineal Models (GLMs), with the presence of the tortoise in 1 km2 cells as the response variable. We posited the existence of a hierarchical scheme of factors (including climate, relief and lithology, and land‐use) that determine the distribution of Testugo graeca in southeastern Spain. We also identified the environmental variables within each factor with the greatest explanatory power and decoupled local vs landscape effects. Climate, followed by relief and lithology, and then land‐use, turned out to be the most important factor shaping the distribution of T. graeca in south‐east Spain as well as determining the presence of the species within its range. Univariate models showed that the main climate constraints were related to rainfall and extreme minimum temperatures, two factors which could be related to constraints imposed by the length of the annual activity period and productivity. Finally, multi‐scale decomposition suggested that neighbouring habitat and local dynamics may also be important in the distribution of the species at the landscape scale.

Aim Recent biogeographical studies have postulated a North African, Late Pleistocene, origin for some species of the Iberian Peninsula. However, a robust assessment of such range expansions requires high-resolution molecular tools to resolve overlapping biogeographical and cultural processes. Here we aim to determine whether the spur-thighed tortoise, Testudo graeca, arrived in southeastern Spain during historical or prehistoric times, and whether its dispersal to the Iberian Peninsula was human-mediated.Location The western Mediterranean Basin (south-eastern Spain, northern Algeria and north-western Morocco).Methods Using 428 samples from 19 sites in North Africa and 18 in southeastern Spain, we obtained mitochondrial sequences from the cytochrome b gene and genotypes derived from seven microsatellite loci. These data were employed to obtain population genetics descriptors, haplotype networks, Bayesian cluster analyses and isolation-by-distance patterns. Moreover, we used a Bayesian demographic approach to delimit the dates involved in the range expansion.Results We found lower levels of genetic variability and weak mitochondrial differentiation in the south-eastern Spanish tortoises compared with the North African ones. However, exclusive haplotypes occurred in the Iberian samples and microsatellite cluster analyses revealed moderate levels of admixture across both sides of the Mediterranean. A coastal area in the west of Algeria and the central-southern region in south-eastern Spain are suggested as the most probable founder and arrival places, respectively. Finally, we identified signatures of an ancient bottleneck event approximately 20,000-30,000 years ago. Main conclusionsThe spur-thighed tortoise probably arrived in south-eastern Spain during Late Pleistocene sea-level low stands. The role that humans may have played as dispersers across the Mediterranean remains unclear. Our results are in accordance with other recent findings of trans-Mediterranean expansions during this period and highlight the importance of employing precise methodological approaches before a species can be considered as historically introduced.

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Much of our current knowledge about the genetic dynamics in range expansions originates from models, simulations and microcosm experiments that need to be corroborated by field data. Here, we report a neutral genetic pattern that matches the predictions of the genetic surfing theory. Genetic surfing occurs when repeated founding events and genetic drift act on the wave of advance of an expanding population, promoting strong spatial structure. In the range expansion of the tortoise Testudo graeca from North Africa to southeastern Spain, we found several genetic signatures consistent with surfing: a decrease of genetic diversity with distance from the initial founder area, clinal patterns in allele frequencies, rare African alleles which have become common at distal sites in the Spanish range, and stronger spatial differentiation in the expanded range than in the original one. Our results provide support for the theory that genetic drift can be an important force in shaping the genetic structure of expanding populations.

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