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Island populations may have a higher extinction risk due to reduced genetic diversity and need to be managed effectively in order to reduce the risk of biodiversity loss. The Eurasian red squirrels (Sciurus vulgaris) in the south of England only survive on three islands (the Isle of Wight, Brownsea and Furzey islands), with the Isle of Wight harbouring the largest population in the region. Fourteen microsatellites were used to determine the genetic structure of red squirrel populations on the Isle of Wight, as well as their relatedness to other populations of the species. Our results demonstrated that squirrels on these islands were less genetically diverse than those in Continental mainland populations, as would be expected. It also confirmed previous results from mitochondrial DNA which indicated that the squirrels on the Isle of Wight were relatively closely related to Brownsea island squirrels in the south of England. Importantly, our findings showed that genetic mixing between squirrels in the east and west of the Isle of Wight was very limited. Given the potential deleterious effects of small population size on genetic health, landscape management to encourage dispersal of squirrels between these populations should be a priority.

Biodiversity conservation approaches are increasingly being implemented at the landscape-scale to support the maintenance\ud of metapopulations and metacommunities. However, the impact of such interventions on the provision of ecosystem services\ud is less well defined. Here we examine the potential impacts of landscape-scale conservation initiatives on ecosystem\ud services, through analysis of five case study areas in England and Wales. The provision of multiple ecosystem services was\ud projected according to current management plans and compared with a baseline scenario. Multicriteria analysis indicated\ud that in most cases landscape-scale approaches lead to an overall increase in service provision. Consistent increases were\ud projected in carbon storage, recreation and aesthetic value, as well as biodiversity value. However, most study areas\ud provided evidence of trade-offs, particularly between provisioning services and other types of service. Results differed\ud markedly between study areas, highlighting the importance of local context. These results suggest that landscape-scale\ud conservation approaches are likely to be effective in increasing ecosystem service provision, but also indicate that associated\ud costs can be significant, particularly in lowland areas.

1.The development of ecological networks could enhance the ability of species to disperse across fragmented landscapes and could mitigate against the negative impacts of climate change. The development of such networks will require widespread ecological restoration at the landscape scale, which is likely to be costly. However, little information is available regarding the cost-effectiveness of restoration approaches. 2.We address this knowledge gap by examining the potential impact of landscape-scale habitat restoration on the value of multiple ecosystem services across the catchment of the River Frome in Dorset, England. This was achieved by mapping the market value of four ecosystem services (carbon storage, crops, livestock and timber) under three different restoration scenarios, estimating restoration costs, and calculating net benefits. 3.The non-market value of additional services (cultural, aesthetic and recreational value) was elicited from local stakeholders using an online survey tool. Flood risk was assessed using a scoring approach. Spatial Multi-Criteria Analysis (MCA) was conducted, incorporating both market and non-market values, to evaluate the relative benefits of restoration scenarios. These were compared with impacts of restoration on biodiversity value. 4.Multi-Criteria Analysis results consistently ranked restoration scenarios above a non-restoration comparator, reflecting the increased provision of multiple ecosystem services. Restoration scenarios also provided benefits to biodiversity, in terms of increased species richness and habitat connectivity. However, restoration costs consistently exceeded the market value of ecosystem services. 5.Synthesis and applications. Establishment of ecological networks through ecological restoration is unlikely to deliver net economic benefits in landscapes dominated by agricultural land use. This reflects the high costs of ecological restoration in such landscapes. The cost-effectiveness of ecological networks will depend on how the benefits provided to people are valued, and on how the value of non-market benefits are weighted against the costs of reduced agricultural and timber production. Future plans for ecological restoration should incorporate local stakeholder values, to ensure that benefits to people are maximised. © 2012 The Authors. Journal of Applied Ecology © 2012 British Ecological Society.

Sustainable use of wildlife is crucial to ensuring persistence of natural resources. We used age-specific survival and breeding data to parameterize a demographic model for a harvested Kazakh saker falcon (Falco cherrug) population by radiotagging juveniles and estimating adult turnover with DNA-fingerprinting during 1993–1997. We gathered similar data during 1990–1998 to model populations of British buzzards (Buteo buteo), and during 1980–1998 to model populations of Swedish goshawks (Accipiter gentilis). Leg-bands and implanted microtransponders provided ways to test for bias and to estimate the harvest of sakers for falconry. Despite an estimated minimum first-year survival of only 23%, the observed productivity of 3.14 young per clutch would sustain a saker population (i.e., λ = 1) with a breeding rate (at laying) of only 0.63 for adults or with a residual juvenile yield of 37% if all adults breed. Higher first-year survival rates for goshawks and buzzards correlated with juvenile yields of up to 71%, but no more than half as many individuals if adults also were harvested. An annual population decline of 40% for sakers in southern Kazakhstan could be explained by observed productivity of only 0.71 young per clutch if there was also an estimated harvest of 55% of adults. This study shows that demographic models such as these can now be built rapidly if nestlings are fitted with reliable and safe radiotags and adult turnover is estimated from genetic analyses or other techniques.

In animal pairs, males are often more vigilant than females. This is generally assumed to result from mate guarding (either against predators or other males). However, when males have conspicuous secondary sexual characteristics, they could be constrained to be more vigilant because of a higher predation risk than females. We attempted to distinguish between the ‘‘male constraint hypothesis’’ and two variations of the mate-guarding hypothesis by studying the vigilance behavior of the sexually dimorphic wigeon during early winter, when some males are in breeding plumage and some are not and when not all males are paired. The proportion of time spent vigilant by paired males in breeding plumage was five times higher than any other category of males or females. We found no significant differences between the vigilance levels of unpaired male wigeon in cryptic and in breeding plumage and therefore rejected the male constraint hypothesis. As vigilance levels of paired and unpaired females did not differ either, we rejected the hypothesis that paired males invest in vigilance to reduce their mate’s need to be vigilant to predation risks. Paired females interacted less frequently with other wigeon than unpaired ones, and it is probably to protect their female from other males that paired male wigeon increase their vigilance times. Key words: Anas penelope, Eurasian wigeon, mate guarding, predation risk, sexual differences, vigilance. [Behav Ecol 14:724–729 (2003)]

The demography of red and grey squirrels was studied by live-trapping and radio-tagging at 14 deciduous and conifer sites in southern Britain and at eight conifer sites for one year in northern England. Densities and productivity correlated with tree seed crops for both squirrel species in deciduous and conifer habitats. Productivity was reduced by high density of full-grown squirrels relative to seed abundance. In oak-hazel woods, demography of grey squirrels correlated with abundance of acorns but not of hazel-nuts, whereas density and productivity of red squirrels correlated with hazel-nut abundance. Correlations of female density and productivity with pine-cone crops did not differ between red and grey squirrels. Predators ate many radio-tagged grey squirrels in conifers, and annual survival was only 50% compared with 80-82% for both species in other habitats. Grey squirrel populations in southern conifer sites were sustained by immigration, and at northern sites female density correlated with oak abundance within 500m. Failure to exploit acorn crops puts red squirrels at a competitive disadvantage in deciduous woodland. Red squirrels had higher survival than grey squirrels in conifers, which may give them an advantage in that habitat, but could also have been explained by a lack of predators on their island study site.

In order to test whether Common Buzzards Buteo buteo that dispersed early were entrepreneurs or exiles, we determined standardised autumn ranges by radio-tracking 67 juveniles during 1990-94. Of these, 11 had dispersed more than 2 km from their natal nest, and had therefore left the natal territory. Buzzards that dispersed early had more fragmented ranges than those that delayed dispersal until the following spring; otherwise no range characteristic differed between the two groups. When only the dispersers were considered, increase in distance from the natal nest was associated with a decrease in range size (r = 0.74) and an increase in the proportion of arable land within the range (r = 0.77). Further investigation revealed that range size was affected by distance from the nest but not by arable habitat. The smaller range size of distant dispersers, combined with evidence of increased productivity among them, suggests that they were more likely to have been entrepreneurs than exiles.