The reproductive periods of brown trout (Salmo trutta) populations in 12 rivers in the Baetic Mountains in southern Spain were studied from 2008 to 2013. This area is an ecological and geographical limit for the distribution of this species in Europe. We found that the spawning period has been markedly extended in these fish. The mean spawning dates in the studied populations are consistent with the European trend at this latitude, but our data suggest that females from most of the populations that we studied are able to produce eggs from early October through late April or early May, yielding a reproductive period of between 150 and 170 days, the longest and most delayed brown trout reproduction periods that have been reported in the literature. We believe that such expanded spawning periods result primarily from the unpredictability of the Mediterranean climate, although it is possible that other factors may have contributed to the development of this reproductive behaviour. This hypothesis is discussed in the context of a comparison of our results with those found for other European S. trutta populations.

The classical debate about the roles of endogenous factors and external drivers in regulating populations continues to be a very active area of scientific research, and these roles are even more complex in populations located in geographically marginal areas. We tested three hypotheses on two separate brown trout populations inhabiting the southernmost basins of the Iberian Peninsula, with the aims of determining the relationships among (a) rainfall and air temperature for each season preceding fish sampling and the observed age group densities; (b) environmental synchrony and density synchrony for all possible pairs of sites; and (c) physical habitat similarity and the similarity of the density response to climatic drivers among pairs of sites. For this purpose, demographic series (98 surveys at 14 sampling sites), climatic conditions (rainfall and air temperature) and site habitat characteristics (physiogeographic and quality index values) were analysed between 2006 and 2014. The results show how the synchrony in the study populations is the result of a Moran effect directed mainly by winter precipitation and conditioned by the habitat similarity (highlighting the altitude, the distance to the upper limit and IHF index, along with the Euclidian distance among pairs of sites of the whole set of habitat variables). Preserving the heterogeneity of these habitat characteristics will increase the resilience of trout populations that inhabit this rear edge of distribution. The current context of global climate warming predicts extremely drastic changes in the dynamics of external drivers that regulate the trout populations in the study region.

1. Understanding factors that regulate the patterns of diversity, richness, and density of organisms is of enormous importance to manage biodiversity in a global change context.2. We investigate the importance of environmental factors in regulating the patterns of diversity, richness, and density of diurnal butterflies in the Sierra Nevada mountain range (SE Spain).3. Diversity, richness, and density seem to be strongly correlated, being mainly defined by land-use and topographic-related variables. The sites with the highest values correspond to areas of dense scrubland, near patches of forest, oriented to the west and with a high rate of solar radiation but not excessively exposed from the topographical point of view. Topographic wetness index seems to be also important but with a positive relation in the case of density and negative in the case of diversity and richness. 4. Our results show a pattern of mid-elevation maxima, with highest values between 1600 and 2000 masl and lower in the summits and the piedmont (<1400 masl). This brings us the possibility to identify a series of areas of high value for the conservation of butterflies in this protected area, with important applications towards the conservation and management of this group of insects.5. Finally, a series of management recommendations to improve the conservation status of the butterfly communities in the Sierra Nevada protected area are inferred.One of the main recommendations is based on the maintenance of spatial heterogeneity, taking into account traditional land uses that enhance biodiversity.