Bennie J.,University of Exeter |
Hodgson J.A.,University of York |
Hodgson J.A.,University of Liverpool |
Lawson C.R.,University of Exeter |
And 6 more authors.
Ecology Letters | Year: 2013
Ecological responses to climate change may depend on complex patterns of variability in weather and local microclimate that overlay global increases in mean temperature. Here, we show that high-resolution temporal and spatial variability in temperature drives the dynamics of range expansion for an exemplar species, the butterfly Hesperia comma. Using fine-resolution (5 m) models of vegetation surface microclimate, we estimate the thermal suitability of 906 habitat patches at the species' range margin for 27 years. Population and metapopulation models that incorporate this dynamic microclimate surface improve predictions of observed annual changes to population density and patch occupancy dynamics during the species' range expansion from 1982 to 2009. Our findings reveal how fine-scale, short-term environmental variability drives rates and patterns of range expansion through spatially localised, intermittent episodes of expansion and contraction. Incorporating dynamic microclimates can thus improve models of species range shifts at spatial and temporal scales relevant to conservation interventions. © 2013 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.
Loos J.,Lüneburg University |
Loos J.,Lund University |
Kuussaari M.,Finnish Environment Institute |
Ekroos J.,Lund University |
And 4 more authors.
Landscape Ecology | Year: 2015
Context: Agricultural transformation and increased land use intensity often lead to simplified landscapes and biodiversity loss. For animals, one possible mechanism underpinning biodiversity loss in agricultural landscapes is the disruption of movements. The disruption of movements may explain, for example, why butterfly communities in agricultural landscapes are often dominated by generalist species with high mobility.Objectives: Here, we investigated how the movement patterns of butterflies characterised by different levels of mobility changed along a gradient of agricultural land use intensity.Methods: To this end, we studied 15 landscapes in low-intensity farmland in Central Romania, measuring 10 ha each and covering a gradient of landscape heterogeneity and woody vegetation cover. In these landscapes, we tracked movements of 563 individuals of nine butterfly species.Results: Our findings showed that overall movement activities differed significantly between species, corresponding well with expert-derived estimates of species-specific mobility. Interestingly, species of low and high mobility responded in opposite ways to increasing levels of landscape heterogeneity. In relatively simple landscapes, the movement patterns of low and high mobility species were similar. By contrast, in complex landscapes, the flight paths of low-mobility species became shorter and more erratic, whereas the flight paths of high-mobility species became longer and straighter. An analysis of the land covers traversed showed that most species avoided arable land but favoured the more heterogeneous parts of a given landscape.Conclusions: In combination, our results suggest that non-arable patches in agricultural landscapes are important for butterfly movements, especially for low-mobility species. © 2014, Springer Science+Business Media Dordrecht.
Dean C.,Bournemouth University |
Day J.,RSPB |
Gozlan R.E.,French Natural History Museum |
Green I.,Bournemouth University |
And 2 more authors.
Conservation Evidence | Year: 2013
Crassula helmsii is a semi-aquatic, invasive macrophyte, which has become abundant in wetland habitats across Europe. This species is of conservation concern because heavy invasions form dense carpets within which few other plants species occur. C. helmsii is known to be killed by inundation with seawater, but published information on its response to inundation by less saline water is limited. Growth trials were conducted to investigate the levels of salinity required to kill this species. We found a linear negative relationship between growth rate and salinity across the range from 2 - 8 ppt, but that 8 ppt was required to kill C. helmsii. These findings suggest that C. helmsii growth could be controlled by inundation with saline water of 8 ppt. This may present a method for reducing the negative effects of salt water on co-occurring species, and thus the next stage will be to determine the efficacy of this method in field trials.
Bocklebank H.,Sussex Wildlife Trust
Ecos | Year: 2012
The Wildlife Trusts have been talking about 'bigger, better and more joined-up' conservation for many years, primed by their Living Landscape programme launched in 2006. The Trusts recognise the importance of moving outside nature reserve boundaries and looking at connectivity in the wider countryside. Policies are now catching up with this thinking and the Lawton Review paved the way for the larger-scale aspirations of the 2011 Natural Environment White Paper. This article reflects on work by the West Weald Landscape Partnership. The activity began in 2004, building on research into wildlife connectivity of this landscape from 1998.
Whitbread T.,Sussex Wildlife Trust
Ecos | Year: 2012
Is looking after the environment an act of charity, to be funded by those with the desire to do so, or is it an act of social responsibility to be funded by all? This article considers the dilemmas for conservation in linking its interests to the political priority for economic qrowth.
Scott D.M.,University of Brighton |
Southgate F.,Sussex Wildlife Trust |
Overall A.J.,University of Brighton |
Waite S.,University of Brighton |
Tolhurst B.A.,University of Brighton
Journal of Zoology | Year: 2012
The Eurasian water shrew Neomys fodiens is a semi-aquatic predator of freshwater invertebrates. As water quality affects the diversity and abundance of aquatic invertebrates, water shrews could potentially be used as a vertebrate bio-indicator of water quality. To date, no detailed studies have empirically examined the impacts of water quality on Eurasian water shrew occurrence. Bait-tube surveys were undertaken in winter and summer over 3years at 26 different wetland locations across Sussex, UK, which varied in water quality. Bait tubes were used to confirm water shrew presence at specific sites and derive an index of activity using frequency of occurrence of faeces within tubes. Water quality was measured using six direct physical and chemical indicators (dissolved oxygen, pH, water temperature, ammonia, nitrate and phosphate) and two derived indices of biological indicators based on aquatic invertebrate composition. We found no linear relationship between any physical, chemical or biological water quality indicators and water shrew occurrence. Generalized linear models indicate that water shrew presence and frequency of occurrence are more affected by site and season than water quality. Thus, water shrews may be more tolerant of poor water quality than previously envisaged. Overall, our study indicates that water shrews are not suitable vertebrate bio-indicators of water quality. © 2011 The Authors. Journal of Zoology © 2011 The Zoological Society of London.