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San Vicent del Raspeig, Spain

Sanchez-Fernandez D.,CSIC - National Museum of Natural Sciences | Lobo J.M.,CSIC - National Museum of Natural Sciences | Hernandez-Manrique O.L.,Centro Iberoamericano Of La Biodiversidad Cibio
Diversity and Distributions | Year: 2011

Aim In this study, we (1) determine whether simple species distribution models based on regional data provide incomplete descriptions of potential distributions; (2) investigate whether underrepresented areas where potential distributions are estimated using only regional data are spatially and environmentally structured; and (3) examine why regional data may not adequately describe potential distributions.Location Iberian Peninsula.Methods We used a multidimensional envelope procedure to estimate the potential distributional areas of 73 species of Iberian diving beetles (Dytiscidae) using two data sets (Iberian data and data from the entire range). We used a Mann-Whitney U-test to compare the features (climate, number of database records and proportion of human-transformed land uses) of these underrepresented areas with those of the remaining Iberian territory.Results By comparing species-richness estimates obtained by overlaying predicted species distributions modelled using either global or regional data, we found that some areas of species' potential distributions are underrepresented when only regional data are used. Incomplete estimates of potential distributions when using only Iberian data may be partly attributable to limited survey efforts combined with unique local climates, but none of the considered factors by itself seems to fully explain this underrepresentation.Main conclusions Our results show that species data from regional inventories may provide an incomplete description of the environmental limits of most species, resulting in a biased description of species' niches. The results of distribution models based on partial information about the environmental niche of a species may be inaccurate. To minimize this error, we highlight the importance of considering all known populations of a given species or at least a sample of populations distributed across the whole range, to include environmental extremes of the distribution. We highlight some methodological and conceptual concerns that should be considered when attempting to infer potential distributions from occurrence data. © 2010 Blackwell Publishing Ltd. Source

Hernandez-Manrique O.L.,Centro Iberoamericano Of La Biodiversidad Cibio | Hernandez-Manrique O.L.,CSIC - National Museum of Natural Sciences | Numa C.,Centro Iberoamericano Of La Biodiversidad Cibio | Verdu J.R.,Centro Iberoamericano Of La Biodiversidad Cibio | And 2 more authors.
Insect Conservation and Diversity | Year: 2012

1.Using a recently created database representing the joint effort of around 100 invertebrate taxonomists, this study uses the information on 52 arthropoda and 27 mollusca species that are endangered and critically endangered to examine to what extent invertebrate species are represented in existing Spanish protected areas. 2.As distribution information is available at a 100km 2 resolution, we consider different area thresholds to judge cells as being protected. 3.Approximately 19% of the area represented by the grid cells with observed occurrences rates as extant protected reserves, and 36% is included within the Natura 2000 network. 4.If having 50% of the cell area as a Natura 2000 reserve is considered as sufficient to have effective protection, almost 68% of species and 32% of probable populations (contiguous cell groups) would be represented. 5.However, 77% of species and 94% of probable populations are not represented in the current protected reserves if we establish that at least 95% of each cell area should belong to a reserve to provide effective protection. 6.Thus, existing conservation strategies, which are based primarily on the protection of certain areas and vertebrate species, may be insufficient to ensure the conservation of invertebrate species. © 2012 The Royal Entomological Society. Source

Hernandez-Manrique O.L.,Centro Iberoamericano Of La Biodiversidad Cibio | Hernandez-Manrique O.L.,CSIC - National Museum of Natural Sciences | Sanchez-Fernandez D.,CSIC - National Museum of Natural Sciences | Verdu J.R.,Centro Iberoamericano Of La Biodiversidad Cibio | And 3 more authors.
Biodiversity and Conservation | Year: 2012

Local autocorrelation statistics offer new opportunities for the discrimination of important conservation areas since the spatial dependence of local values upon neighbouring ones may assist conservation decisions. We exemplify the use of local autocorrelation statistics for conservation purposes using data on Spanish threatened invertebrates to identify areas composed of similarly species-rich localities (hot spots), species-rich "islands", cold spots and species-poor "islands". In order to assess the probable causes of the detected patterns differences in environmental, land use and protected area variables were examined between the different regions. Distributional data for threatened invertebrate species in Spain at 100 km 2 UTM cell resolution were used. After defining a neighbouring area, statistically significant local autocorrelation values (both positive and negative) were estimated. Kruskal-Wallis ANOVA by rank test was used to compare the environmental, land use and protected area percentages between the cells of the different regions. Around 11 and 2 % of total cells can be considered hot spots and rich "islands", respectively. Hot spots are characterized by a lower percentage of anthropic land uses and a higher percentage of current protected area. However, approximately a third part of these cells possess at least 98 % of their area unprotected. Rich "island" cells are not environmentally different from those considered as cold spots, though experiencing a lower rate of anthropization and higher proportion of protected area. Unfortunately, almost 70 % of these rich "island" cells have <2 % of their areas currently protected. The use of local autocorrelation statistics on species richness values may complement conservation decisions by discriminating interconnected sites facilitating local persistence (hot spots) as well as isolated and vulnerable sites (rich "islands"). The study of different variables associated with these regions allows us to suggest determinant causal factors. Our results suggest that land use changes due to human activities are the main cause of threats. © 2012 Springer Science+Business Media B.V. Source

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