The great fruit-eating bat (Artibeus lituratus) is a large-sized species that forages primarily on fruits. This species is widespread throughout the Neotropics, where it is common in natural areas and also occupies forest patches and cities. In this study, we review the composition of Artibeus lituratus diet in Brazil as well as the size of fruits and seeds, plant geographic origin, and sampling methods used in natural versus urban habitats. We show that Artibeus lituratus is able to consume a higher proportion of exotic fruits with large seeds in urban environments than in natural areas. Fruit diameter was not statistically different between environments, but both fruit and seed diameters are smaller when detected by fecal sampling than by other methods. This difference is likely due to the fact that in natural habitats studies are predominantly based on fecal samples, which hinders the detection of large unswallowed seeds. Consequently, we recommend the use of complementary sampling methods (not only the widely used technique of fecal sorting) in order to produce more accurate descriptions of frugivorous bats’ diets. We suggest that the ability to exploit fruits of exotic plant species including the ones with large seeds may be a key trait for the persistence of A. lituratus in urban habitats.

Seed predation has been suggested to play a crucial role in plant population dynamics and could act as a strong selective force in the evolution of plant traits such as plant phenology, size and number of flowers. The loss of seeds could be particularly threatening for population maintenance of rare plant species. We investigated the influence of seed predators on plant fitness of the rare monocarpic thistle Cirsium decussatum. We tested the following hypotheses: (1) pre-dispersal seed predators reduce the number of dispersed propagules; (2) seed predators select larger inflorescences as oviposition sites; (3) the size of the capitulum is correlated with seed productivity; and (4) seed predators compete for the oviposition sites. We identified ten insect taxa from different taxonomic groups in the capitula of C. decussatum. Terellia longicauda larvae (Diptera: Tephritidae) were the most common. The presence of the flies’ larvae was positively correlated with the predation level in the capitula. Females of T. longicauda selected larger inflorescences for laying eggs that may increase offspring fitness as larger inflorescences promise more food resources. We could not prove the presence of competition between insect species inhabiting the capitula. Our data suggest, however, that T. longicauda, a specialized seminophagous dipteran, is one of the factors that negatively influence the fitness of threatened C. decussatum, lowering significantly the seed pool. Terellia longicauda potentially acts as a strong selective force in the evolution of C. decussatum inflorescence size.

The pollination ecology and breeding system of Trochetia granulata (Malvaceae), an endemic tree species from Réunion were studied. In 2010–2011, compatibility studies were conducted on a total of 154 flowers from 35 different individuals using three different hand pollination treatments: (a) autofertility, (b) self-pollination and (c) cross-pollination. During the period, we also studied the pollination ecology of T. granulata. During 48 h of video recordings, we tracked flower visits to T. granulata in six different sites and studied the behaviour of the visitors. The results from the hand-cross experiments show that T. granulata is self-compatible (60.8% fruit set) but cannot produce fruit (5.4% fruit set) without the visit of a pollen vector. During surveys, four different visitors were reported: the introduced honey bee (Apis mellifera), two endemic species of white-eye (Zosterops borbonicus borbonicus and Z. olivaceus) and the endemic Réunion day gecko (Phelsuma borbonica). This study documented a new case of vertebrate-pollination by lizard and birds in an insular context. These interactions might be linked to several uncommon floral traits of Trochetia species.

Forest fragmentation can alter herbivory on tree recruits with possible consequences for regeneration. We assessed effects of forest-fragment quality (tree diversity, vegetation complexity, relative abundance of pioneer trees) and matrix habitat on arthropods and herbivory in KwaZulu-Natal, South Africa. We compared arthropod abundances and herbivory on woody seedlings and saplings among four forest-fragment types differing in size and matrix (large fragments and small fragments surrounded by natural grassland, eucalypt and sugarcane plantations; nplots = 24) using analyses of covariance. We recorded 3385 arthropods and inspected 897 seedlings (71 species) and 876 saplings (91 species). Relative abundance of predators increased with fragment quality; that of herbivores decreased. Herbivory responses to fragment quality varied: seedling herbivory decreased with relative abundance of pioneers and sapling herbivory increased with vegetation complexity. Matrix effects were low with little variation in relative abundance of predators (0.39–0.53) and herbivores (0.22–0.32), proportion of seedling (8.3–11.0%) and sapling herbivory (12.4–14.3%) among the forest-fragment types. These findings indicate that herbivory on tree recruits is mediated by forest-fragment quality rather than matrix habitat. Future studies should evaluate whether contrasting effects of fragment quality on arthropods and herbivory are caused by weak trophic interactions and variable herbivore compositions.

A honeydew-producing scale insect, Stigmacoccus garmilleri (Margarodidae), is associated with oak trees (Quercus spp.) in highland forests of Mexico. Although feeding by ants on scale-insect honeydew is more frequently documented in the literature, the honeydew produced by feeding instars of S. garmilleri is sufficient to provide nourishment for birds. This study elucidates bird use of honeydew in the tropical montane forests near Chiconquiaco, Veracruz, Mexico, and uncovers patterns in honeydew foraging. Over a 2-mo period, 40 trees harbouring scale insects, located in both forest and pasture areas, were intensely studied (160 h of bird-foraging observations along with quantitative measurements of honeydew production). Fifteen resident bird species and 18 migrant species were observed visiting observation trees. Approximately 72% of the resident bird species and 83% of the migrant bird species observed were recorded to forage on scale-insect honeydew. Audubon's warbler (Dendroica coronata auduboni) was the most active consumer and defender of the resource. Of 118 aggressive chases observed, only 9.65% occurred in forest observation trees, and 90.3% in pasture trees. Audubon's warbler demonstrated preferential defence and territorial patrolling of scale-insect honeydew in scattered pasture trees.

We studied the effect of climate on the plant-pollinator communities in the West Indies. We constructed plots of 200 m × 5 m in two distinct habitats on the islands of Dominica, Grenada and Puerto Rico (total of six plots) and recorded visitors to all plant species in flower. In total we recorded 447 interactions among 144 plants and 226 pollinator species. Specifically we describe how rainfall and temperature affect proportional richness and importance of the different pollinator functional groups. We used three measures of pollinator importance: number of interactions, number of plant species visited and betweenness centrality. Overall rainfall explained most of the variation in pollinator richness and relative importance. Bird pollination tended to increase with rainfall, although not significantly, whereas insects were significantly negatively affected by rainfall. However, the response among insect groups was more complex; bees were strongly negatively affected by rainfall, whereas dipterans showed similar trends to birds. Bird, bee and dipteran variation along the climate gradient can be largely explained by their physiological capabilities to respond to rainfall and temperature, but the effect of climate on other insect pollinator groups was more obscure. This study contributes to the understanding of how climate may affect neotropical plant-pollinator communities.

Oviposition site selection in insects is essential in terms of low egg mortality, high offspring survival and therefore a high reproductive output. Although oviposition height could be a crucial factor for the fitness of overwintering eggs, it has rarely been investigated. In this study the oviposition height of a polyphagous leaf beetle, Galeruca tanaceti Linnaeus in different habitats and at different times of the season was examined and its effect on egg clutch mortality was recorded. The leaf beetle occurs as an occasional pest on several agricultural plants. It deposits its eggs within herbaceous vegetation in autumn. Eggs are exposed to numerous biotic and abiotic mortality factors summarized as egg parasitism and winter mortality. Oviposition height of the leaf beetle was not uniform, but changed significantly with the structure of the habitat and during the season. Mean oviposition height per site (70.2±4.9 cm) was significantly higher than mean vegetation height (28.4±2.4 cm). Height of plants with egg clutches attached and oviposition height were significantly positively correlated. The results suggest that females try to oviposit as high as possible in the vegetation and on the plants selected. In accordance with this, the probability of egg parasitism and of winter egg clutch mortality significantly declined with increasing oviposition height. A preference of G. tanaceti for oviposition sites high up in the vegetation might therefore have evolved due to selection pressures by parasitoids and winter mortality.