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Planted woodland islets act as sources of seed that may accelerate woodland development in extensive agricultural landscapes. We assessed a 1-ha plot that was planted with 16 100-m2 islets of holm oak Quercus ilex subsp. ballota seedlings near Toledo (Spain) in 1993. In spring 2014 we measured (1) acorn predation and (2) seedling emergence from seeded acorns at different distances from and orientations around the islets with half of the acorns protected to prevent predation, (3) survival of emerged seedlings, and (4) natural tree establishment outside of the planted islets. Most (96.9 %) unprotected acorns were removed or predated. Seedling emergence from protected acorns ranged from 42.9 % on the northern side of the islets to 13.2 % on the southern side, suggesting a less stressful microclimate on the northern side. Survival of naturally established seedlings was 28.6 % by the end of first summer; seedling mortality was chiefly due to drought (45.0 %) and herbivory (35.0 %). Density of emerged seedlings, surviving seedlings after first dry season, and established oaks >1-year old was similar at different distances from the islets. Over the 21 year time period, 58 new oak individuals >1-year old have established (an average of 3.3 established individuals per ha per year) at an average distance of 6.3 ± 5.4 m away from the closest islet. We conclude that initial oak regeneration triggered by small planted islets in Mediterranean abandoned farmland is slowed down by high acorn predation, seedling herbivory, and stressful microclimatic conditions. Regardless, these islets are a viable tool for regeneration of Mediterranean oak woodland.

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.

Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Novel ecosystems have emerged through human intervention and are rapidly expanding around the world. Whether they can support animal wildlife has generated considerable controversy. Here we developed a new approach to evaluate the ability of a novel forest ecosystem, dominated by the exotic tree species Eucalyptus globulus, to support animal wildlife in the medium and long term. To evaluate this ability, we took advantage of the fact that species territory size decreases with increasing habitat quality, and we used territoriality of a raptor guild composed of Northern Goshawk (Accipiter gentilis), Eurasian Sparrowhawk (A. nisus) and Common Buzzard (Buteo buteo) as indicator. We compared the territoriality of these species in the novel ecosystem with that in other ecosystems found in the literature. Average distances between con-specifics in the novel ecosystem were similar, or even shorter, than those in other ecosystems. Average distances between Goshawk con-specifics were among the shortest described in the literature. All three species nested preferably in mixed stands abundant in large exotic trees, with high structural complexity and abundance of native species within the stand. Key factors supporting this diverse and dense raptor community were the special forest management system implemented in the study area and the agricultural matrix located close to forest plantations that complements the supply of prey. Our results suggest that forest management that promotes a complex and suitable forest structure can increase the ability of novel forest ecosystems to support wildlife biodiversity, particularly a diverse nesting community of forest-dwelling raptors and their preys. The results further suggest the suitability of territoriality for assessing this potential of novel ecosystems., Competing Interests: The authors have declared that no competing interests exist.

Scatter-hoarding animals such as corvids play a crucial role in the dispersal of nut-producing tree species. This interaction is well known for some corvids, but remains elusive for other species such as the magpie (Pica pica), an abundant corvid in agroecosystems and open landscapes of the Palearctic region. In addition, the establishment of the individual dispersed seeds-a prerequisite for determining seed-dispersal effectiveness-has never before been documented for the interaction between corvids and nut-producing trees. We analyzed walnut dispersal by magpies in an agroecosystem in southern Spain. We used several complementary approaches, including video recording nut removal from feeders, measuring dispersal distance using radio tracking (with radio transmitters placed inside nuts), and monitoring the fate of dispersed nuts to the time of seedling emergence. Magpies were shown to be highly active nut dispersers. The dispersal distance averaged 39.6 ± 4.5 m and ranged from 4.1 to 158.5 m. Some 90% of the removed walnuts were cached later, and most of these (98%) were buried in the soil or hidden under plant material. By the time of seedling emergence, ca. 33% of nuts remained at the caching location. Finally, 12% of the cached nuts germinated and 4% yielded an emerged seedling, facilitating the transition to the next regeneration stage. The results demonstrate for the first time that magpies can be an effective scatter-hoarding disperser of a nut-producing tree species, suggesting that this bird species may play a key role in the regeneration and expansion of broadleaf forests in Eurasia.

Diet studies present numerous methodological challenges. We evaluated the usefulness of commercially available trail-cameras for analyzing the diet of Northern Goshawks (Accipiter gentilis) as a model for nesting raptors during the period 2007-2011. We compared diet estimates obtained by direct camera monitoring of 80 nests with four indirect analyses of prey remains collected from the nests and surroundings (pellets, bones, feather-and-hair remains, and feather-hair-and-bone remains combined). In addition, we evaluated the performance of the trail-cameras and whether camera monitoring affected Goshawk behavior. The sensitivity of each diet-analysis method depended on prey size and taxonomic group, with no method providing unbiased estimates for all prey sizes and types. The cameras registered the greatest number of prey items and were probably the least biased method for estimating diet composition. Nevertheless this direct method yielded the largest proportion of prey unidentified to species level, and it underestimated small prey. Our trail-camera system was able to operate without maintenance for longer periods than what has been reported in previous studies with other types of cameras. Initially Goshawks showed distrust toward the cameras but they usually became habituated to its presence within 1-2 days. The habituation period was shorter for breeding pairs that had previous experience with cameras. Using trail-cameras to monitor prey provisioning to nests is an effective tool for studying the diet of nesting raptors. However, the technique is limited by technical failures and difficulties in identifying certain prey types. Our study also shows that cameras can alter adult Goshawk behavior, an aspect that must be controlled to minimize potential negative impacts.