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Throughout the European Union, the EC Habitats Directive requires that member states undertake national surveillance of designated species. Despite biological connections between-populations across-borders, national assessments need not be co-ordinated in any way. We conducted a trans-boundary assessment of the status of Eurasian otters (Lutra lutra) aimed at providing consistency across a single biogeographical unit, i.e. the island of Ireland, comprising two states, i.e. the Republic of Ireland and the United Kingdom (Northern Ireland). Our aim was to ensure consistency with previous assessments conducted separately in each state, and permit each Government to fulfil their separate statutory reporting commitments. The species range increased by 23% from 1996-2006 and 2007-11. The population estimate of 9400 [95%CI 8700-12,200] breeding females during 2010/11 was not significantly different from 8300 [95%CI 7600-9800] breeding females established as a baseline during 1981-82. Modelling of species-habitat associations suggested that available habitat was not limiting and no putative pressures recorded at sites surveyed negatively affected species occurrence. Thus, under the statutory parameters for assessing a species' conservation status, i.e. range, population, habitat and future prospects, the otter was judged to be in 'Favourable' status throughout Ireland and in both discrete political jurisdictions. Thus, we provide a trans-boundary test case for EU member states that share habitats and species across ecoregions, ensuring conservation assessment data are standardised, synchronised, spatially consistent and, therefore, biologically relevant without compromising legal and administrative autonomy within separate jurisdictions. [ABSTRACT FROM AUTHOR]

Understanding how invasive species spread is of particular concern in the current era of globalisation and rapid environmental change. The occurrence of super-diffusive movements within the context of Lévy flights has been discussed with respect to particle physics, human movements, microzooplankton, disease spread in global epidemiology and animal foraging behaviour. Super-diffusive movements provide a theoretical explanation for the rapid spread of organisms and disease, but their applicability to empirical data on the historic spread of organisms has rarely been tested. This study focuses on the role of long-distance dispersal in the invasion dynamics of aquatic invasive species across three contrasting areas and spatial scales: open ocean (north-east Atlantic), enclosed sea (Mediterranean) and an island environment (Ireland). Study species included five freshwater plant species, Azolla filiculoides, Elodea canadensis, Lagarosiphon major, Elodea nuttallii and Lemna minuta; and ten species of marine algae, Asparagopsis armata, Antithamnionella elegans, Antithamnionella ternifolia, Codium fragile, Colpomenia peregrina, Caulerpa taxifolia, Dasysiphonia sp., Sargassum muticum, Undaria pinnatifida and Womersleyella setacea. A simulation model is constructed to show the validity of using historical data to reconstruct dispersal kernels. Lévy movement patterns similar to those previously observed in humans and wild animals are evident in the re-constructed dispersal pattern of invasive aquatic species. Such patterns may be widespread among invasive species and could be exacerbated by further development of trade networks, human travel and environmental change. These findings have implications for our ability to predict and manage future invasions, and improve our understanding of the potential for spread of organisms including infectious diseases, plant pests and genetically modified organisms. [ABSTRACT FROM AUTHOR]

Highlights: [•] Maximum entropy modelling was used to identify kittiwake feeding habitats. [•] Extent of optimal habitat and reproductive success declined between years. [•] MPA designation may be less effective where variability in feeding habitat is high. [•] Complementary approaches to the current proposed MPA networks are advocated. [Copyright &y& Elsevier]

Abstract: Although widespread, the ecology of the whiskered bat, Myotis mystacinus in Europe remains poorly understood. Ireland is positioned at the most western extreme of this species’ range. To ascertain the ecology of M. mystacinus at its geographic range extreme, the roosting behaviour, home range and habitat use of females in a maternity roost in Ireland was investigated by radio-tracking. M. mystacinus were active in a diversity of habitats: namely, mixed woodland, riparian vegetation, arable land and rough grassland. However, only mixed woodland and riparian habitats were selected as core foraging areas. This is in contrast to a previous study from Britain where only pasture was utilised but is in agreement with data from Slovakia, where woodland was also selected, whilst riparian areas were also utilised by this species in Germany. A high degree of overlap in the foraging areas of individuals was observed. A total of seven roosts were utilised by tracked bats and roost switching behaviour was observed. We discuss our contrasting results in respect to range limitations, regional variability in landscape structure and the composition of bat communities. The present results have implications for the conservation of M. mystacinus within Ireland and other parts of its range, highlighting the need for range wide ecological studies. Regional variability in the ecology of bats related to landscape factors is an important consideration for bat conservation and therefore must be incorporated into future management plans. [Copyright &y& Elsevier]

In this study, the growth pattern of juvenile European hake (Merluccius merluccius) was analyzed in relation to oceanographic and ecological factors in the Ligurian Sea and northern Tyrrhenian Sea, both part of the Mediterranean Sea. The ages of juvenile European hake, collected during a trawl survey in June 2011, were estimated by reading otolith daily growth rings. The growth pattern (length-age relationship) of juvenile European hake recruited to the population (<1 year old) was analyzed by fitting a multivariate generalized additive model with explanatory variables: depth, bottom temperature, sea-surface temperature, scalar wind speed, chlorophyll-α concentration, and fish density (number of individuals per square kilometer). A significant effect of density on the length-age relationship was found, and an increased growth rate at densities >3000 individuals km-2. This observed positive effect of density on growth could be argued to be a consequence of favorable environmental conditions, such as food availability and temperature, where both fish density and growth are maximized. Conversely, areas of lower density correspond to habitats of low suitability, where growth is impaired. [ABSTRACT FROM AUTHOR]

Climate influences the biogeography of bats, their access to food, timing of hibernation, reproduction and development, frequency and duration of torpor and rate of energy expenditure., Empirical data on the impact of climate change on bats are a cause for concern as current increases in global temperature are one fifth, or less, of those expected over the next century., We review observed impacts of climate change on bats and identify risk factors allowing species-specific predictions., The impact on species is reviewed in relation to six aspects, namely foraging, roosting, reproduction, biogeography, extreme weather events and indirect effects of climate change. For some aspects of species' ecology, there are insufficient data available to make accurate assessment of impacts., We identify seven risk factors encompassing three broad aspects: biogeography - small range size, high latitude or high altitude range and a range occupying a geographic area likely to become water stressed; foraging niche - frugivory and species restricted to aerial hawking; dispersal ability - species with restricted dispersal behaviour., We use the European and north-west African bats as a case study to assess the relative risk of climate change to individual species. Risk scores are compared with existing International Union for Conservation of Nature conservation assessments providing further insight into the conservation outlook for individual species., We provide a base for Chiroptera to be incorporated into future frameworks of risk assessment and identify areas that require further research. [ABSTRACT FROM AUTHOR]