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Populations inhabiting the periphery of species distribution ranges may experience suboptimal environmental conditions and higher vulnerability to anthropogenic pressures. Disentangling the role of natural and human-related factors and the relationships among them in these marginal areas is thus key to understand and prevent species declines and range reductions. We analysed Eurasian otter (Lutra lutra) occurrence patterns in relation to anthropogenic pressures and natural environmental gradients in Morocco, an area constituting the arid limit of the species' global range. The probability of otter occurrence was higher as terrain ruggedness increased and at intermediate elevations, and lower in catchments exposed to higher anthropogenic pressures. Otters tended to be rare at higher elevations and in areas with less annual precipitation, probably as a result of trophic resource limitations and large water flow fluctuations, respectively. A combination of natural and anthropogenic factors, both at drainage area and local scales, was needed to understand the current occurrence of the species. Our study highlights a need for urgent action to conserve the Eurasian otter in northern Africa, where freshwater ecosystems and their associated biodiversity are threatened by rapid human development in areas of marginal climatic conditions. [ABSTRACT FROM AUTHOR]

1. Desert rivers are highly dynamic systems in which dry periods, frequently involving the cessation of superficial flow, alternate with violent flash floods. In spite of their territorial importance and high functional and biological diversity, desert rivers have received little attention in the scientific literature, especially in Northern Africa. 2. This study investigated the distribution of non-native fish, their relationship with river damming and their potential impacts on native biodiversity in the main river basins draining arid areas of Morocco (Oued Draa, Oued Ziz and Oued Ghir), based on field sampling covering 84 stream reaches. 3. Thirteen fish species were recorded, eight of which are non-native. Two species (stone moroko, Pseudorasbora parva, and bleak, Alburnus alburnus) had not been previously recorded in Morocco, while the native sandsmelt (Atherina boyeri) had not been cited as an invader. Pumpkinseed (Lepomis gibbosus) was the most widely distributed non-native fish. 4. Non-native fish species were associated with reservoirs, colonizing the regulated downstream reaches. In contrast, unregulated upstream reaches tended to be free of non-natives. The low abundance of native fish in reservoirs seems to be caused by the impacts of introduced fish species. 5. Management options for environmental flow are limited, owing to reduced water availability. Non-native fish management should thus focus on limiting the spread of species already introduced and avoiding new introductions, especially into reservoirs. [ABSTRACT FROM AUTHOR]

Although the Near Threatened Eurasian otter Lutra lutra has been recovering in Europe since the 1980s nothing is known about population trends of the species in northern Africa. Ninety sites was searched for signs of otters in northern and western Morocco in 1983 and we repeated this survey in 2011. At each site we searched for otter spraints (faeces) or clear footprints along a maximum of 600 m of river bank, ending the search when the first sign was found. Overall results were strikingly similar in 1983 and 2011, with 36 positive sites and the same general distribution pattern of the species. Healthy otter populations appear to remain in the foothills of the Middle and High Atlas but the trend of populations disappearing from the relatively flat Atlantic slope has increased. The results are in clear contrast with the recovery of otter populations in Europe, probably because of differences in the implementation of environmental policies, especially regarding water pollution. [ABSTRACT FROM PUBLISHER]

Some of the most arid environments inhabited by the Eurasian otter (Lutra lutra) are the river systems draining the southern slopes of the High Atlas Mountains into the Sahara Desert, where we have studied otter distribution, habitat use and feeding ecology. We found signs of otter presence in 61% of 80 sampled sites. The species was widespread at intermediate elevations within the study area, being rarer at high altitudes (above 2000 m a.s.l.) and, especially, in the arid lowlands. The intensity of habitat use, estimated from spraint counts, also peaked at intermediate elevations. Otter diet, described through the analysis of 554 spraints, was dominated by fish in general (found in 97% of the spraints) and Luciobarbus barbels in particular (86% of spraints). The otter positively selected barbels of intermediate sizes (100–160 mm in length), avoiding the smallest size classes and consuming larger ones according to their availability. Our results suggest that otter may be vulnerable to the harsh environmental conditions in arid areas. This aridity-driven vulnerability is expected to increase in the area and to expand to other peri-Mediterranean regions in the future. • Pre-Saharan river systems represent the arid extreme of the otter distribution. • Otters occupy mainly mid-elevations within a steep elevation gradient. • Luciobarbus barbels are the primary prey of otters in the area. • Aridity may involve local extinctions and hinder recolonization. • Aridity-driven vulnerability will increase in the area and expand geographically. [ABSTRACT FROM AUTHOR]

Simple Summary: The trading and collection of wildlife for pets is one of the main threats for the conservation of some species worldwide. Assessing the human dimension of it is essential to improve our understanding of its drivers, which may help inform the design of effective species conservation strategies. We address this issue using the Mediterranean spur-thighed tortoise (Testudo graeca) as a case study. This species has sharply declined in its native range, tortoise trade and non-commercial collection for pets being some of the main threats. In fact, both uses have been documented in southern Europe and northern Africa, although this species has been protected by the Convention on International Trade in Endangered species of Wild Fauna and Flora (CITES) since 1975. Our study, which was based on a questionnaire survey, (i) demonstrated that many people in Rabat city (Morocco) and surroundings keep tortoises as pets (55%; n = 480), most of which had been collected directly from wild populations, and (ii) highlighted the limited ecological and biological knowledge of tortoise owners (mainly of those living in the city of Rabat) on the species. Our findings evidence how both the sociological context and the role of consumers/harvesters play a major part in this problem with international projection. We discussed deeply how tortoise non-commercial collection might affect its conservation and welfare, and recommended appropriate actions that focus on strengthening collection bans. The trading and collection of wild animals as pets may be cause for concern regarding animal welfare and species conservation. These concerns can be exemplified by Mediterranean spur-thighed tortoise (Testudo graeca), a long-living species whose use as pets is long established. The human dimension plays a major role in the wildlife for the pet collection, and is particularly important in countries like Morocco, where this might pose a threat to the conservation of the species involved. This study, which is based on a questionnaire survey (n = 480 participants), documents the fact that many people in Morocco keep tortoises as pets: 55% of the participants in the survey and over two tortoises/person. Importantly, most captive tortoises, particularly juveniles, had been collected directly from wild populations by their owners (42%, n = 264). In general, the tortoise owners had limited knowledge of their tortoises' habits and requirements, although rural people were more likely to acknowledge that the tortoise is a wild and threatened species. Our study reveals that non-commercial collection is a common activity in Morocco that may threaten wild tortoise populations and hence species conservation, and it could have consequences regarding the welfare of the animals. We were also able to identify the profile of people towards whom education campaigns should be directed in order to reduce the number of tortoises collected from wild populations. Additional field research should also be conducted to quantify the impact of pet collection on wild tortoise populations. [ABSTRACT FROM AUTHOR]