Global bee decline and its impact on pollination in agricultural and natural ecosystems have attracted public attention. However, more data are needed to show their generality and intensity in different ecosystems, especially in the tropics. For centuries, the tropical dry forest (TDF) of Costa Rica underwent intense deforestation, but in the last four decades, a large part of this forest has entered a recovery process. Using data of orchid bees generated by Janzen et al. (Ecology, 63, 66) in TDF in the Santa Rosa sector of the Guanacaste Conservation Area (ACG), we posed a general question: What changes have occurred in diversity, composition, and seasonality of the euglossine bee community in the TDF during the last 40 years and how are these changes related to the current recovery of this forest. We sampled euglossine bees during 2018–2019 using methods similar to those applied previously. To characterize the response of euglossine bees to habitat loss, we extended the sampling to pastures adjacent to the protected area. With the loss (n = 4) and gain (n = 3) of bee species, we did not find significant changes in overall species richness between now and 40 years ago. However, the composition of the euglossine community in the protected area in 1977 was more similar to that found in current pastures than to the current community in forests, where the presence of forest‐dependent species has been favored. It is possible that TDF regeneration in Santa Rosa has led to changes in the composition of the community of these bees. Abstract in Spanish is available with online material.

In human-modified tropical landscapes, the survival of arboreal vertebrates, particularly primates, depends on their plant dietary diversity. Here, we assessed diversity in the vegetative diets of Costa Rican non-human primates (i.e. Alouatta palliata palliata, Ateles geoffroyi, Cebus imitator, and Saimiri oerstedii) inhabiting a range of habitat types. Specifically, we assessed: (i) richness and dietary plant diversity, (ii) the β-diversity of dietary plant species and the relative importance of species turnover and nestedness in contributing to these patterns, and (iii) the main ecological drivers of the observed patterns in dietary plant assemblages. Data on diet were available for 33 Alouatta, 15 Cebus, 8 Ateles, and 5 Saimiri groups, from 37 published and unpublished studies. Considering all studies, dietary plant species richness was highest in Alouatta (454 spp.), followed by Ateles (329 spp.), Cebus (237 spp.), and Saimiri (183 spp.). However, rarefaction curves indicated that the diversity of plant species in diet was higher in Ateles than in the other three primate species. The diversity of plants was 868 species (range=1664-2041 species). The three top food species were Spondias mombin, Bursera simaruba, and Samanea saman. Species turnover was the mechanism responsible for most of the dissimilarity in the plant assemblages in diet (Beta-sim = 0.76). Finally, primate species, habitat type and, to a lesser degree, sampling effort were the best predictors of the dietary plant assemblages. Our findings suggest that primate diets are diverse, even in severely-disturbed habitats.

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Tropical areas are vital for conserving endangered tree species. However, barriers to the propagation and storage of plant material still limit preservation outcomes. Seed traits are essential in conservation but have rarely been applied in the tropics. In this work, we compile information about the germination and seed desiccation tolerance behaviour of 953 arboreal species from the Osa Peninsula, Costa Rica. We analysed how those traits are related to the growing strata, seed size, and dispersal mode and how they can be used to improve conservation initiatives based on the species distribution, abundance, extinction risk, and ex situ cultivation. Over a third of the species are probably recalcitrant but this number increase to almost half among the endangered and endemic ones. Most species have seeds dispersed by animals, but wind dispersal is usually orthodox and dominant in secondary forests. All species with tiny seeds and most understorey ones with small seeds are orthodox. Approximately half of the species have dormant seeds, while nearly one-third of nondormant species have cohorts with extended germination. Almost half of the species are conserved ex situ; however, several endangered, endemics could be expected to be considered exceptional. Seed traits could target orthodox species for seed banking in tropical forests, including the potential of secondary forests and a subset of oligarch species. For the recalcitrant ones, approaches based on the risk of extinction, distribution, abundance, and ex situ status allow for prioritizing collection and conservation strategies. Under this approach, we develop a list with priority species.