Establishing ecological networks across national boundaries is essential for species to adapt to shifts in future suitable climate zones. This paper presents a method to assess whether the existing ...ecological network in the Dutch – German border region is “climate proof”. Using distribution data and climate envelope models for 846 species in Europe (mammals, birds, reptiles, amphibians and butterflies) we identified 216 species with climate-induced range shifts in the border region. A range expansion is predicted for 99 species and the ranges of 117 species are predicted to contract. The spatial cohesion of the ecological network was analysed for selected species that vary in habitat requirements and colonisation ability (forest species: Brenthis daphne, Dendrocopos medius; wetland species: Maculinea teleius, Lutra lutra). The assessment shows that optimising transboundary networks and developing corridors seems a suitable adaptation strategy for the forest species and for L. lutra. For the immobile butterfly M. teleius, the present habitat network is too weak and translocation into future suitable climate space seems to be a more appropriate adaptation measure. Our results underline that due to climate change landscape planning and management should not only focus on areas where target species occur today. The presented method can identify strongholds and bottlenecks in transboundary ecological networks and incorporate demands of climate adaptation into spatial planning which forms the basis for taking measures at a more detailed level.
Der Biotopverbund gilt als eine zentrale Anpassungsstrategie des Naturschutzes an die Folgen des Klimawandels. In der vorliegenden Arbeit wurde untersucht, welchen Beitrag Biotopverbundsysteme zwischen Deutschland und den Niederlanden zur Anpassung von klimawandelbedingten Arealverschiebungen von Arten leisten können. Durch eine vergleichende Analyse von Verbreitungsdaten und Klimahüllen-Modellen von 846 Tierarten (Säugetiere, Vögel, Reptilien, Amphibien und Tagfalter) wurden 216 Arten identifiziert, die in Zukunft potenziell grenzüberschreitende Arealverschiebungen aufgrund von Gewinnen (99 Arten) oder Verlusten (117 Arten) von klimatisch geeigneten Gebieten erfahren werden. Für ausgewählte Arten der Wälder (Brenthis daphne, Dendrocopos medius) sowie der Gewässer- und Feuchtlebensräume (Maculinea teleius, Lutra lutra) wurde die funktionale Kohärenz der vorhandenen Biotopverbundsysteme modelliert und vor dem Hintergrund der Arealverschiebungen bewertet. Dadurch, dass Wanderungskorridore und Kernlebensräume erhalten, entwickelt und neu geschaffen werden, können die Arten der Wälder und Lutra lutra potenziell bei der Realisierung der Arealverschiebungen unterstützt werden. Die für den Biotopverbund relevanten Bereiche wurden grenzüberschreitend räumlich dargestellt. Für die wenig mobile Tagfalterart Maculinea teleius ist die Kohärenz des Netzwerkes vermutlich zu gering, so dass eine Umsiedlung in klimatisch geeignete Lebensräume als Anpassungsmaßnahme vorgeschlagen wird. Die Ergebnisse verdeutlichen, dass sich Biotopverbundplanungen in Zeiten des Klimawandels nicht nur auf die Gebiete konzentrieren sollten, in denen Zielarten bereits heute vorkommen. Mit der vorgestellten Methode können die potenziellen Auswirkungen von Klimaänderungen mit Relevanz für den grenzüberschreitenden Biotopverbund ermittelt werden, so dass eine Grundlage für Maßnahmenkonzepte auf regionaler und lokaler Ebene zur Verfügung steht.
Over the centuries, mowing and grazing have been crucial for sustaining populations of grassland insects and their overall diversity in Europe. While long-term positive effects of mowing have been ...studied in more detail, little is known about the direct impacts of mowing on adult butterflies. Here, we explore how different habitat management (mown, recovered after mowing and unmown) affects movements and population estimates of the endangered specialist butterfly
. The results showed higher dispersal probability from mown (22%) and recovered meadows (16%) than from the unmown ones (9%). However, mowing shortened the average dispersal distances (mown = 102 m, recovered = 198 m, unmown = 246 m) and reduced butterfly population size. In contrast, a larger area of the habitat patches promoted long-distance dispersal and sustained larger populations. We hypothesise that mowing caused depletion of resources and triggered dispersal of poorly adapted individuals. This behaviour is maladaptive and could lead to higher dispersal-related mortality; thus, mowing should be avoided before and during the butterfly flight period. This study suggests that the species' persistence in a fragmented landscape depends on large, unmown and interconnected habitats that support more viable populations, promote long-distance dispersal, and enable (re)colonisation of vacant patches.
The parasitic relationship between
butterflies and
ants has been extensively studied but little information is available on the spatial occurrence of
larvae. We searched for the presence of
in 211 ...ant nests at two sites in two crucial phases of its life cycle, i.e., in autumn, during the initial larval development, and in the following late spring, before pupation. We assessed variations in the proportion of infested nests and factors correlated with spatial distributions of parasites in
colonies. The parasitism rate in autumn was very high (∼50% of infestation rate) but decreased in the following spring. The most important factor explaining parasite occurrence in both seasons was the nest size. Further factors, such as the presence of other parasites, the
species or the site, concurred to explain the differential survival of
until the final development. Irrespective of the host nest distribution, the parasite distribution changed from even in autumn to clumped in late spring. Our work showed that the survival of
is correlated with colony features but also with the nest spatial distribution, which therefore should be taken into consideration in conservation strategies aiming at preserving these endangered species.
One of the key challenges in designing agri-environmental schemes targeted at conservation is the determination of the amount of financial resources that should be allocated towards a particular aim ...such as the conservation of an endangered species. Economists can contribute to an answer by estimating the ‘optimal level of species conservation’. This requires an assessment of the supply and the demand curve for conservation and a comparison of the two curves to identify the optimal conservation level. In a case study we estimated the optimal conservation level of Large Blue butterflies (protected by the EU Habitats Directive) in the region of Landau, Germany. The difference to other studies estimating optimal conservation is that a problem was addressed where costs and ecological effects of conservation measures are heterogeneous in space and over time. In our case study we found a corner solution where the highest proposed level of butterfly conservation is optimal. Although our results are specific to the area and species studied, the methodology is generally applicable to estimate the amount of financial resources that should be allocated to conserve an endangered species in the context of agri-environmental schemes.
Population growth and spread of recently reintroduced species is crucial for the success of their reintroduction. We analysed what limits the spread of two congeneric butterfly species Maculinea ...teleius and Maculinea nausithous, over 10 years following their reintroduction. During this time, their distributions appeared to be limited to a few sites although it was thought that more suitable habitats were available. Thus, we question, does the quality or the spatial arrangement of their habitat limit their spread? Although adult individuals of both species can select high-quality plots, we show that selection of suitable plots in the area of reintroduction is spatially constrained. A low colonization probability of unoccupied distant plots of high quality was found for both species. The abandonment of occupied plots in Ma. teleius was also found to be dependent on the distance to occupied plots. We conclude that the spatial distribution of the two species during the 10 years following reintroduction was limited by the spatial arrangement of their habitat, rather than by the availability of high-quality plots. The spatial constraints in movement can explain observed source-sink structures when female butterflies deposit their eggs on low-quality plots. We conclude that although these species have very similar life histories, they require different approaches to their conservation due to subtle differences in adult habitat use and movement. Conservation of Ma. teleius should concentrate on improving local habitat quality, whereas conservation of Ma. nausithous is predicted to be more effective by creating a spatial network of suitable habitat plots, such as along road verges.
Payments for environmental services (PES) are widely adopted to support the conservation of biodiversity and other environmental goods. Challenges that PES schemes have to tackle are (i) ...environmental uncertainty and (ii) information asymmetry between the provider of the service (typically a farmer) and the regulator. Environmental uncertainty calls for action-based payment schemes, because of the more favorable risk allocation if the farmer is risk-averse. Information asymmetry, on the other hand, calls for a performance-based payment, because of the more direct incentives for the farmer. Based on a principal-agent model, we study the optimal combination of both, performance-based and action-based payments under conditions of environmental uncertainty and asymmetric information. We find that for a risk-neutral regulator a combination is optimal in the majority of cases and that the welfare gain of the combined scheme over a pure action-based (performance-based) payment increases with information asymmetry (environmental uncertainty). We further show that for a regulator who is risk-averse against fluctuations in environmental goods provision the optimal performance-based payment is lower than for a risk-neutral regulator. We quantitatively illustrate our findings in a case study on the enhancement of the butterfly Scarce Large Blue (Maculinea teleius) in Landau/Germany.
► We study how performance- and action-based payments should be optimally combined. ► We analyze a principal-agent model of conservation contracting. ► We show how the optimal PES scheme depends on uncertainty and asymmetric information. ► Optimal performance-based payments decrease with the regulator's risk aversion. ► A case-study of butterfly conservation shows that the welfare gains may be large.
Although the behaviour of the Large Blue butterflies of the genus
(=
) is relatively well studied, most empirical data come from investigations of their dispersal and oviposition. Here, we assessed ...overall intersexual differences in resource use by tracking
(Bergsträsser, 1779) individuals and recording the duration of their behaviours. Females were characterised by frequent, short flights, and devoted more time to resting and oviposition. Males engaged in numerous, but usually short interactions, and spent most of the time in flight exploring their surroundings for receptive females. Their average flight time was significantly longer compared to females. Average feeding time did not differ between the sexes but was shorter when butterflies were feeding on
L. Intraspecific interactions within
were three times longer than those with other insect species, and interactions between sexes were particularly long lasting. Significantly shorter interspecific interactions imply that butterflies can easily recognise conspecifics and differentiate between sexes, which offers obvious fitness benefits. Both sexes, but especially females, showed strong association with their larval host plant, and less so with other flowers of similar colour and shape. Females predominantly used their host plant for feeding, which possibly indicates neuro-sensory constraints towards this resource.
Less transformed and managed grassland habitats in Asia serve as a good frame of reference for studies on demographics and ecological situations of grassland species in Europe. In this study, using ...AFLPs (transposon insertion display), we compared the genetic structures of populations of the endangered and highly specialised scarce large blue (Phengaris teleius, Bergsträsser, 1779) butterfly from Europe (Germany, Poland, and Ukraine) and Asia (Siberia and Mongolia).
There are no differences in levels of intra‐population genetic variability between European and Asian P. teleius populations. Nevertheless, we found significantly higher genetic differentiation (wider scattering) among European populations than among Asian populations. All examined Eurasian populations were admixed, except for those from the Bavarian region (Germany) where an atypical genetic structure was observed for P. teleius. Individual membership probabilities to a population were higher and more variable among European populations than among Asian populations. Comparison of genetic spatial structures revealed an isolation‐by‐distance effect in both European and Asian populations. Genetic autocorrelation analysis showed that significant dissimilarity among individuals first appeared at a distance of 1800 km at Asian sites, but at only 400 km at European sites.
The observed P. teleius genetic structure reveals substantial differences in the quality of connectivity among European and Asian populations, which favour Asian populations. It suggests that differences between European and Asian P. teleius population genetic structures have the origin in differences in habitat structures, emphasising the impact of habitat fragmentation on animal movement in Europe.
Intra‐population levels of genetic variation of Phengaris teleius are similar in Europe and Inner Asia. Populations from both of those super‐regions are admixed.
European populations exhibit larger genetic population differentiation than populations in Inner Asia. Also, isolation‐by‐distance is significant in Europe and non‐significant in Asia.
Genetic local structure among Asian individuals is three times larger than among European individuals. This indicates on stronger effects of isolation and habitat fragmentation in European populations.
A model of interspecific host competition in a system with one parasite (butterfly—
Maculinea
) and multiple potential hosts (ants—
Myrmica
) is presented. Results indicate that host interspecific ...competition increases the occurrence of multiple host behaviour in
Maculinea
natural populations but decreases the ability of the parasite populations to adapt to the most abundant host species. These qualitative predictions were compared with data on host specificity, with good agreement. Analysis of the data also indicates that
Maculinea teleius
and
Maculinea arion
respond differently to changes in relative host abundances.
Maculinea teleius
shows a larger fraction of sites where it displays multiple host behaviour and a larger fraction of sites where the niches of the hosts overlap. In some instances,
Maculinea teleius
is adapted to
Myrmica
hosts that are present in lower frequencies.
Maculinea arion
is locally more host-specific and occurs at sites where host interspecific competition is unlikely and is more frequently adapted to the most abundant host species.
PDF
