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Adult males of many migratory species arrive at breeding grounds before females and young. In a 34-year study of the masked shrike, Lanius nubicus, an age- and sex-specific pattern of spring arrival was distinguished. Adult males arrived first followed by juvenile males and adult females, whereas juvenile females appeared last. We hypothesized that these differences in migratory strategies would be reflected in a differential response to climate conditions at the wintering grounds. Testing correlations between spring arrival time and winter climate conditions provided strong support to our hypothesis. Adult males’ arrival time exhibited high associations with climate conditions in early spring, upon migratory take-off, whereas juvenile males responded mostly to conditions in November, upon autumn arrival in Africa. Adult females responded to both parameters in autumn and early spring, whereas young females’ arrival correlated only with a few variables in autumn. GLM models of median spring arrival day for all categories but the young females were highly statistically significant with adjusted R-squared values of 0.81–0.93. The emerging pattern of different associations between timing of spring migration and climate conditions at the wintering grounds sheds new light on existing evolutionary theories regarding age- and sex-specific migratory strategies.

Land sharing strategies in agricultural landscapes need to allow for organisms to move between natural areas and different crops within an agro-ecological landscape in order to reduce extinction probability and the negative effects of small isolated populations. In this study, we tested whether legume or wheat fields differed in their effects on reptiles’ movement patterns. We conducted our study in an agro-ecosystem consisting of small isolated natural habitat patches nested within agricultural fields. We trapped reptiles in sampling arrays before and after harvest in both wheat and legume fields, and in adjacent natural habitat patches. For both crops, prior to harvest, we found an increase in movements of Trachylepis vittata, the most common reptile in our study, from the natural habitat patches into fields, but negligible movement in the opposite direction. In both crops before harvest, the individuals that moved into the fields were adults of better body condition than those remaining in the natural habitat patch, suggesting that long-distance movements were only possible for individuals with high prospective fitness. After harvest, no movements were documented between wheat fields and natural habitat patches. However, in legume fields, a high symmetrical movement (i.e. in both directions) of individuals of similar body condition between fields and natural habitat patches took place. Importantly, newborn lizards were only found in the natural habitat patches and in post-harvest legume fields. Our results suggest that agricultural heterogeneity, through a mixture of crop types may mitigate some of the negative effects of particular crops on biodiversity. As crop rotation between wheat and legume fields is common worldwide, our findings highlight the importance of creating an agricultural mosaic to enhance biodiversity permeability within the agricultural matrix.

This is the first population genomic analysis that examines micro-evolutionary changes in co-occurring plant species, in fragmented habitats, along a precipitation gradient. We applied Genotype-by-Sequencing (GBS) on three different annual Asteraceae on the same sites that share similar life history strategies, but different pollination and dispersal strategies (Catananche lutea, Geropogon hybridus, Urospermum picroides). We tested if the genetic diversity for all species correlates with effective population sizes along the precipitation gradient and whether therefore genetic drift drives evolution at range edges. However, our results support this hypothesis for only one species (C. lutea) but refute it for the other two. Potential genomic signals of adaptation to the high precipitation gradient were found only in one species (U. picroides). We also tested if species with complex pollination and diversified dispersal strategies are less affected by small scale habitat fragmentation, but the opposite is true. Biological differences between the species studied (pollination and dispersal) explain population genetic differences along the precipitation gradient at range edges rather than environmental filters. Pairwise correlation analyses showed no or only weak similarities in the accumulation of mutations in the different species. Our results suggest that the processes driving evolution in different co-occurring species are different, so that most genomic similarities in our investigations may only represent temporary stages in evolution.

Intensive agricultural activity over large areas on earth, which is necessary to meet the increasing demand of a growing human population, may lead to biodiversity loss. This loss may be mitigated by keeping natural and semi-natural patches within agricultural fields to allow the maintenance of biological diversity (‘Wildlife Friendly Agriculture’). We conducted our study in an agroecosystem comprised of small isolated patches nested within agricultural fields. We trapped reptiles in 13 sampling sites, each of which included arrays of pitfall traps in a natural patch, in the adjacent wheat field and at the patch-field edge. We conducted six trapping sessions in the spring – four times before, once immediately after and once a week after the wheat harvest. Prior to the harvest, we found an intensive movement of Trachylepis vittata, the most common reptile in our study, from the semi-natural patches into the fields, but negligible movement in the opposite direction. This pre-harvest directional movement corresponded with higher abundance of prey (i.e., arthropods) in the wheat field compared to the natural patches in early spring. The individuals that moved into the fields were adults of better body condition than those remaining in the patch, suggesting that the motivation for movement was habitat preference by individuals with high prospective fitness rather than the exclusion of subordinates. The population of T. vittata in the wheat fields and movement across habitats dropped to zero during and after the harvest. Our results provide strong evidence that the agricultural fields serve as an ecological trap to organisms inhabiting nearby natural habitats. We suggest that plans for Wildlife-Friendly Agriculture for biodiversity conservation should consider also potential negative effects, such as the ecological trap effect.

We studied the distribution of arthropods in the Arava desert on both sides of the Israeli-Jordanian border, to assess the impact of different anthropogenic pressures on the local fauna. We examined how different landscape units, proximity to agricultural fields, and human societies, might affect the diversity of ground dwelling beetles, and spiders, using ordination and diversity estimation methods. Our results suggest that although both countries contain similar habitats, each has its own unique characteristics, probably due to different cultural practices. The immediate repercussion is that loss of a habitat on one side of the border cannot be compensated with preservation of the same habitat across the border, due to fauna dissimilarity. For example, beetle species can be assembled according to landscape units, but within each landscape unit they show dissimilarities that are based on the geopolitical location. Spiders fail to assemble according to landscape units but cluster as a unique group within Israel. Both landscape unit type and the border, were found to be important for the overall species diversity of this ecosystem and therefore “redundancy” should be carefully applied, especially across geopolitical borders.

The peace treaty between Israel and Jordan found the Arava desert ecosystem, shared by the two countries, in a state of developmental dichotomy. On the Israeli side, vast lands have been settled and transformed into agricultural fields, while the Jordanian side has remained relatively intact and inhabited by only a few traditional and pastoral societies. This study examined the effect of different landscape units and proximity to agriculture on reptile diversity and rodent community structure on both sides of the border. It appears that in addition to the effect of proximity to agricultural fields and landscape habitat, the border between the two countries may play a role in determining diversity on the respective sides. While reptile abundance was generally higher on the Israeli side of the border, diversity was found to be significantly higher on the Jordanian side. Rodent community structure also revealed significant differences between the two sides of the border, mainly due to the more favorable conditions for psammophilic gerbils in Jordan. When comparing Western society with pastoral traditional society, it appears that development activities of the former have altered diversity and community structure of the taxa studied in the Arava. We suggest that in addition to the effects of habitats and human disturbances, such as modern agricultural practices, cultural differences between societies should be considered when conservation plans are developed for cross-border ecosystems.

Major progress has been made recently in our understanding of large-scale ecological processes and patterns. Here, a spatially explicit, multi-species, process-based, object-oriented landscape simulation model (SHALOM) is described that is built upon major lessons from fields such as metapopulation dynamics and landscape ecology. Consistent with the current landscape ecology terminology, SHALOM has physical classes (landscape, habitat, cell, patch) and biological classes (population, species, community). Each class has functions and characteristics that are strongly based on ecological realism. Processes of SHALOM are modelled on local and global scales. At the local scale, populations grow continuously, and are affected by: (1) a community-level saturation effect (ratio between energy consumed by all populations in a patch and the energy offered by that patch); (2) a species-habitat match (match between a species' niche space and the patch's habitat space); and (3) demographic stochasticity (inverse population-size dependent residuals from deterministic birth and death rates). The global-scale processes of the model include fitness-optimizing migration and catastrophic stochasticity (disturbance) that can be controlled for its probability, intensity, and spatial range. The processes of the model use allometric relationships and energy as a common currency to bridge differences between species of different body sizes located in habitats of different productivities. These processes also allow both intraspecific and interspecific effects to take place simultaneously without assuming a specific relationship between the two. Hence, SHALOM, with its functions and procedures, opens new opportunities to study combined ecosystem, community and population processes. Simulation results given in the paper on species composition and diversity show that the integration of interspecific competition, demographic stochasticity and dispersal revealed different predictions when different combinations of these processes were used. One novel prediction was that the complex relationship between dispersal and demographic stochasticity caused the global extinction of the largest species. This, in turn, might have further implications for conservation. Overall, the model represents a synthetic approach that provides ways to explore high-level ecological complexity and suggests predictions for future studies of macroecological questions.