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Diplolepis (Hymenoptera: Cynipidae) are gall wasps that induce conspicuous galls on Rosa spp. (Rosaceae). These species are distributed globally and in Europe some are especially common and are founder organisms of biological communities composed of different insects. However, the ecological niches of these species have not been studied in detail. We modelled the potential distributions of these species using the locations of the galls of the four most abundant species of Diplolepis on the Iberian Peninsula (Diplolepis mayri, Diplolepis rosae, Diplolepis eglanteriae and Diplolepis nervosa, the galls of latter two are indistinguishable) using four different algorithms and identified the resulting consensus for the species. We compared the potential distributions of these species, considering their spatial complementarity and the distributions of their host plants. We found that D. mayri and D. eglanteriae/nervosa have complementary distributions on the Iberian Peninsula. The former species is found in the Mediterranean region, while D. eglanteriae and D. nervosa are distributed mainly in the Eurosiberian region. Diplolepis rosae has the widest distribution on the Iberian Peninsula. Our models constitute the first effort to identify suitable areas for species of Diplolepis species on the Iberian Peninsula and could be useful for understanding the evolutionary ecology of these species throughout their distribution in the western Palearctic.

Populations of bumblebees and other pollinators have declined over the past several decades due to numerous threats, including habitat loss and degradation. However, we can rarely investigate the role of resource loss due to a lack of detailed long‐term records of forage plants and habitats.We used 22‐year repeated surveys of more than 262 sites located in grassland, forest, and wetland habitats across Illinois, USA to explore how the abundance and richness of bumblebee food plants have changed over the period of decline of the endangered rusty patched bumblebee Bombus affinis.We documented a decline in abundance of bumblebee forage plants in forest understories, which our phenology analysis suggests provide the primary nectar and pollen sources for foundress queens in spring, a critical life stage in bumblebee demography. By contrast, the per‐unit area abundance of food plants in primarily midsummer‐flowering grassland and wetland habitats had not declined. However, the total area of grasslands had declined across the region resulting in a net loss of grassland resources.Synthesis and applications. Our results suggest a decline in spring‐flowering forest understorey plants is a previously unappreciated bumblebee stressor, compounding factors like agricultural intensification, novel pathogen exposure and grassland habitat loss. These findings emphasize the need for greater consideration of habitat complementarity in bumblebee conservation. We conclude that the continued loss of early season floral resources may add additional stress to critical life stages of bumblebees and limit restoration efforts if not explicitly considered in pollinator conservation. [ABSTRACT FROM AUTHOR]

Riparian galleries are among the most vulnerable habitats in the world and are well known for their importance to the most specialized riparian bird species. In this study, we analyzed songbird composition, songbird diet, trophic ecology and seed dispersal in riparian galleries and adjacent Montado matrices in southern Portugal to address the importance of birds in promoting the connectivity between riparian galleries and adjacent habitats. We used fecal samples to compare diet, and blood samples to compare nitrogen stable isotopes from birds in these two habitats. The seasonal variation in the abundance of arthropods and fruits was evaluated in both habitats and seed movement between both habitats was assessed from fruits marked with fluorescence. Abundance of food resources for birds (arthropods and fruits) declined throughout the season in a similar way for both habitats, and there were strong similarities in the diet and trophic ecology of songbirds in the riparian gallery and adjacent habitat. In both habitats, birds preyed heavily on Hymenoptera and Coleoptera but birds more abundant in the Montado fed more on Araneae and Hymenoptera. Seeds were moved significantly more frequently from the riparian gallery into the adjacent Montado than vice‐versa. Our results suggest that birds from the adjacent habitat move frequently to the riparian gallery to forage and disperse seeds into the adjacent habitat as they depart. This study shows that birds play an important role in promoting connectivity between riparian galleries and adjacent habitats. [ABSTRACT FROM AUTHOR]

There is increasing evidence that non-reef habitats in the seascape surrounding coral reefs are widely used by reef-associated fishes. However, our understanding of seascape use in the Indo-Pacific region is incomplete due to its large geographical range and as a consequence, considerable environmental variation (e.g. tidal regimes). We used remote video cameras to survey reef-associated fishes within five habitat types (coral reef slope, coral reef flat, macroalgal beds, mangroves and seagrass meadows) around the Tigak Islands, Kavieng, Papua New Guinea. Of the 282 shallow-water reef-associated species observed across 360 videos, 35% (99 species) were recorded in non-reef habitats, the majority (78 species) on multiple occasions. We found that macroalgal beds dominated by low-complexity algal genera (e.g. Halimeda, Caulerpa) were used extensively by reef-associated fishes, complementing previous research that has documented the use of canopy-forming macroalgae (e.g. Sargassum). Mean species richness and relative abundances (MaxN) of reef-associated fishes were twofold higher in macroalgal beds than mangroves or seagrass. Interestingly, mangroves contained the most distinct fish assemblage of the three non-reef habitats, including several reef-associated species that were not recorded from any other habitat type. This suggests that mangroves possess attributes not shared by other shallow non-reef, or even reef, habitats. Importantly, many of the fish families commonly found in non-reef habitats (i.e. lethrinids, lutjanids) are targeted by local fishers and are thus critical to sustaining local livelihoods. Our study demonstrates that non-reef habitat use is common for many reef-associated fishes and highlights the need to incorporate a range of habitats into study designs to better understand habitat use patterns in the Indo-Pacific. Given the widespread degradation of coral reefs and other shallow-water habitats, we emphasize the need to recognize that reefs are embedded within a mosaic of habitat types that influence patterns and processes and that management strategies should be scaled appropriately. [ABSTRACT FROM AUTHOR]

Agricultural intensification and associated loss of high‐quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post‐2020 CAP, we performed a European‐scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator‐friendly management, as well as the extent of farmer uptake.A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources.EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early‐season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived.Experts identified substantial opportunities to improve habitat quality by adopting pollinator‐friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen‐fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes.Policy Implications. To conserve pollinators and help protect pollination services, our expert elicitation highlights the need to create a variety of interconnected, well‐managed habitats that complement each other in the resources they offer. To achieve this the Common Agricultural Policy post‐2020 should take a holistic view to implementation that integrates the different delivery vehicles aimed at protecting biodiversity (e.g. enhanced conditionality, eco‐schemes and agri‐environment and climate measures). To improve habitat quality we recommend an effective monitoring framework with target‐orientated indicators and to facilitate the spatial targeting of options collaboration between land managers should be incentivised. [ABSTRACT FROM AUTHOR]