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Aim Typically, non-indigenous species have been studied in relation to either the invaded (recipient) community or the donor community. However, we still lack a broad understanding of the mechanisms underlying the establishment of non-indigenous species that combines both perspectives. Since the opening of the Suez Canal, hundreds of species have invaded the Mediterranean from the Red Sea, forming a unique system in which the entire species pool (donor, non-indigenous and recipient) is known. Focusing on species ecological traits, we assess the drivers underlying the establishment of non-indigenous species from the onset of the invasion to the present. Location The Mediterranean and Red Seas. Methods We compiled traits for shallow-water hard-bottom-associated fishes in the Mediterranean (recipient community) and the Red Sea (donor community). We compared the multivariate community trait structure of non-indigenous species with the donor and recipient assemblages, using a novel method to objectively assign trait-weights, thereby increasing the robustness of the results. Patterns were contrasted with two types of null models which provide distinct insights into the ecological processes. Results Non-indigenous fishes are very diverse ecologically, substantially increasing the total community trait diversity of the Mediterranean. Trait similarity between non-indigenous and indigenous Mediterranean species was lower than expected, indicating that non-indigenous fishes tend to occupy relatively vacant niches within the Mediterranean. However, we further found that over time non-indigenous species display increased trait similarity to indigenous Mediterranean species. This suggests that trait constraints associated with successful establishment are weakening. Main conclusions Non-indigenous species establish in relatively vacant ecological niches, opening the possibility for predicting establishment using ecological traits. However, the weakening of trait constraints through time suggests that forecasting future establishment may be difficult. Faced with an accelerating pace of invasion, it appears that the Mediterranean is going to be transformed into an extension of the Red Sea in terms of trait and species composition. [ABSTRACT FROM AUTHOR]

Successful implementation of marine conservation plans is largely inhibited by inadequate consideration of the broader social and economic context within which conservation operates. Marine waters and their biodiversity are shared by a host of stakeholders, such as commercial fishers, recreational users and offshore developers. Hence, to improve implementation success of conservation plans, we must incorporate other marine activities while explicitly examining trade-offs that may be required. In this study, we test how the inclusion of multiple marine activities can shape conservation plans. We used the entire Mediterranean territorial waters of Israel as a case study to compare four planning scenarios with increasing levels of complexity, where additional zones, threats and activities were added (e.g., commercial fisheries, hydrocarbon exploration interests, aquaculture, and shipping lanes). We applied the marine zoning decision support tool Marxan to each planning scenario and tested a) the ability of each scenario to reach biodiversity targets, b) the change in opportunity cost and c) the alteration of spatial conservation priorities. We found that by including increasing numbers of marine activities and zones in the planning process, greater compromises are required to reach conservation objectives. Complex plans with more activities incurred greater opportunity cost and did not reach biodiversity targets as easily as simplified plans with less marine activities. We discovered that including hydrocarbon data in the planning process significantly alters spatial priorities. For the territorial waters of Israel we found that in order to protect at least 10% of the range of 166 marine biodiversity features there would be a loss of ∼15% of annual commercial fishery revenue and ∼5% of prospective hydrocarbon revenue. This case study follows an illustrated framework for adopting a transparent systematic process to balance biodiversity goals and economic considerations within a country's territorial waters. [ABSTRACT FROM AUTHOR]

Spatial prioritization in conservation is required to direct limited resources to where actions are most urgently needed and most likely to produce effective conservation outcomes. In an effort to advance the protection of a highly threatened hotspot of marine biodiversity, the Mediterranean Sea, multiple spatial conservation plans have been developed in recent years. Here, we review and integrate these different plans with the goal of identifying priority conservation areas that represent the current consensus among the different initiatives. A review of six existing and twelve proposed conservation initiatives highlights gaps in conservation and management planning, particularly within the southern and eastern regions of the Mediterranean and for offshore and deep sea habitats. The eighteen initiatives vary substantially in their extent (covering 0.1–58.5% of the Mediterranean Sea) and in the location of additional proposed conservation and management areas. Differences in the criteria, approaches and data used explain such variation. Despite the diversity among proposals, our analyses identified ten areas, encompassing 10% of the Mediterranean Sea, that are consistently identified among the existing proposals, with an additional 10% selected by at least five proposals. These areas represent top priorities for immediate conservation action. Despite the plethora of initiatives, major challenges face Mediterranean biodiversity and conservation. These include the need for spatial prioritization within a comprehensive framework for regional conservation planning, the acquisition of additional information from data-poor areas, species or habitats, and addressing the challenges of establishing transboundary governance and collaboration in socially, culturally and politically complex conditions. Collective prioritised action, not new conservation plans, is needed for the north, western, and high seas of the Mediterranean, while developing initial information-based plans for the south and eastern Mediterranean is an urgent requirement for true regional conservation planning. [ABSTRACT FROM AUTHOR]

Mountains provide an opportunity to examine changes in biodiversity across environmental gradients and areas of transition (ecotones). Mountain ecotones separate vegetation belts. Here, we aimed to examine whether transition areas for birds and butterflies spatially correspond with ecotones between three previously described altitudinal vegetation belts on Mt. Hermon, northern Israel. These include the Mediterranean Maquis, xero-montane open forest and Tragacanthic mountain steppe vegetation belts. We sampled the abundance of bird and butterfly species in 34 sampling locations along an elevational gradient between 500 and 2200 m. We applied wombling, a boundary-detection technique, which detects rapid changes in a continuous variable, in order to locate the transition areas for bird and butterfly communities and compare the location of these areas with the location of vegetation belts as described in earlier studies of Mt. Hermon. We found some correspondence between the areas of transition of both bird and butterfly communities and the ecotones between vegetation belts. For birds and butterflies, important transitions occurred at the lower vegetation ecotone between Mediterranean maquis and the xero-montane open forest vegetation belts, and between the xero-montane open forest and the mountain steppe Tragacanthic belts. While patterns of species turnover with elevation were similar for birds and butterflies, the change in species richness and diversity with elevation differed substantially between the two taxa. Birds and butterflies responded quite similarly to the elevational gradient and to the shift between vegetation belts in terms of species turnover rates. While the mechanisms generating these patterns may differ, the resulting areas of peak turnover in species show correspondence among three different taxa (plants, birds and butterflies). [ABSTRACT FROM AUTHOR]

An important challenge in ecology is to predict patterns of biodiversity across eco-geographical gradients. This is particularly relevant in areas that are inaccessible, but are of high research and conservation value, such as mountains. Potentially, remotely-sensed vegetation indices derived from satellite images can help in predicting species diversity in vast and remote areas via their relationship with two of the major factors that are known to affect biodiversity: productivity and spatial heterogeneity in productivity. Here, we examined whether the Normalized Difference Vegetation Index (NDVI) can be used effectively to predict changes in butterfly richness, range size rarity and beta diversity along an elevation gradient. We examined the relationship between butterfly diversity and both the mean NDVI within elevation belts (a surrogate of productivity) and the variability in NDVI within and among elevation belts (surrogates for spatial heterogeneity in productivity). We calculated NDVI at three spatial extents, using a high spatial resolution QuickBird satellite image. We obtained data on butterfly richness, rarity and beta diversity by field sampling 100 m quadrats and transects between 500 and 2200 m in Mt Hermon, Israel. We found that the variability in NDVI, as measured both within and among adjacent elevation belts, was strongly and significantly correlated with butterfly richness. Butterfly range size rarity was strongly correlated with the mean and the standard deviation of NDVI within belts. In our system it appears that it is spatial heterogeneity in productivity rather than productivity per se that explained butterfly richness. These results suggest that remotely-sensed data can provide a useful tool for assessing spatial patterns of butterfly richness in inaccessible areas. The results further indicate the importance of considering spatial heterogeneity in productivity along elevation gradients, which has no lesser importance than productivity in shaping richness and rarity, especially at the local scale. [ABSTRACT FROM AUTHOR]

Concern over the impact of invaders on biodiversity and on the functioning of ecosystems has generated a rising tide of comparative analyses aiming to unveil the factors that shape the success of introduced species across different regions. One limitation of these studies is that they often compare geographically rather than ecologically defined regions. We propose an approach that can help address this limitation: comparison of invasions across convergent ecosystems that share similar climates. We compared avian invasions in five convergent mediterranean climate systems around the globe. Based on a database of 180 introductions representing 121 avian species, we found that the proportion of bird species successfully established was high in all mediterranean systems (more than 40% for all five regions). Species differed in their likelihood to become established, although success was not higher for those originating from mediterranean systems than for those from nonmediterranean regions. Controlling for this taxonomic effect with generalized linear mixed models, species introduced into mediterranean islands did not show higher establishment success than those introduced to the mainland. Susceptibility to avian invaders, however, differed substantially among the different mediterranean regions. The probability that a species will become established was highest in the Mediterranean Basin and lowest in mediterranean Australia and the South African Cape. Our results suggest that many of the birds recently introduced into mediterranean systems, and especially into the Mediterranean Basin, have a high potential to establish self-sustaining populations. This finding has important implications for conservation in these biologically diverse hotspots. [ABSTRACT FROM AUTHOR]

Recent studies suggest that patterns of genetic diversity significantly influence the viability and persistence of local populations. Revealing and mapping spatial patterns of genetic diversity within species’ ranges may be vital when defining criteria and prioritizing areas for conservation. Chukar Partridges (Alectoris chukar) in Israel occur along a steep ecogeographical gradient extending from mesic Mediterranean zones in the north to steppe and desert regions in the south. To test the hypothesis that the most genetically diverse populations within a species’ range occur within the ecotone, an area of transition between ecosystems where a sharp environmental gradient exists, we examined the allozyme diversity of chukars collected at five locations within the species’ continuous range in each of 2 years. Based on 32 allozyme loci, the genetic diversity of chukars increased significantly along a gradient from populations in Mediterranean regions to those at the ecotone in the northern Negev desert, despite close geographical proximity among populations. Genetic diversity as estimated by percent polymorphic loci, observed and expected heterozygosity, and mean number of alleles was not homogeneous among sampling localities: single and multilocus Hardy-Weinberg and linkage disequilibria increased along the gradient toward the ecotone. Populations exhibited some isolation by distance effects in the face of substantial gene flow. We therefore recommend that higher conservation priority be assigned to the Mediterranean-Negev ecotone area. For Chukar Partridges, it supports the highest overall genetic diversity as well as unique alleles. Priorities for other populations, moreover, can also be set based on their genetic diversity across ecological gradients. Rapid urbanization of Israeli landscapes threatens to disrupt unique and perhaps essential genetic connections among chukar populations, and management of chukars in Israel within a... [ABSTRACT FROM AUTHOR]

Among potential topics in the new science of biodiversity, understanding the characteristics and impact of invasive birds is an attractive subject to include as part of junior high school biology studies. Birds are aesthetic and raise curiosity. Curiosity about birds, combined with field observations, can stimulate students to ask authentic questions. As birds are among the few wild vertebrates that one can easily observe, students can easily develop systematic methods to answer their questions and initiate a dynamic open inquiry process. The educational project ‘Tracking Invasive Birds’, presented here as a case study, is the result of a unique collaboration among conservation biologists, science educators and biology teachers. High school students participated in an open inquiry process facilitated by teachers, ecologists, and science educators. At the end of the inquiry process, these high school students conducted a bird watching tour for junior high school students. This paper shows how investigating a conservation environmental issue – invasive birds – contributes to the development of both dynamic open inquiry skills and environmental literacy among 11th‐ and 12th‐grade students. [ABSTRACT FROM PUBLISHER]