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Many plants benefit from seed dispersal by frugivorous animals. This mutualistic interaction depends largely on interaction‐relevant matching of functional traits (i.e. fruit size of plants and gape size of frugivores). With declines in large‐bodied animal populations, it is likely that fruit–frugivore interactions have eroded, leading to the loss of seed dispersal of large‐fruited plants. Such erosion could be especially evident in vulnerable island ecosystems such as those in the Caribbean, where most large‐bodied frugivore populations have collapsed due to human activities. Here, we aim to understand the consequences of this decline by first quantifying gaps in frugivory function between common, smaller frugivores (birds, smaller reptiles, and bats) and rarer or regionally extinct, larger reptiles (Cyclura spp. and Chelonoidis spp.) in the Caribbean archipelagos. We then assess the benefits of reestablishing these interactions by determining the effects of large reptile ingestion on seed germination for 10 fruiting species, representing a range of fruit sizes, native to the Caribbean. We found that there are significant gaps in frugivory function, with smaller frugivores having many times smaller mean gape sizes than larger reptiles. Furthermore, we found that most fruiting species used in this study could germinate after being consumed by large reptiles, with two species having their germination speed significantly accelerated post‐ingestion. These results indicate that fruiting plants could benefit from reestablishing frugivorous interactions between larger reptiles and fruiting plants. Given the existing gap in frugivory function, additional attention should be given to the possibility of rewilding defaunated islands to restore plant–frugivore networks. [ABSTRACT FROM AUTHOR]

Seed dispersal by frugivores is essential in plant life cycles, with birds and mammals the principal and well-studied dispersal agents. However, there is an increasing recognition that terrestrial tortoises could also be considered important seed dispersers in many ecosystems. The red-footed tortoise (Chelonoidis carbonaria) is one of the largest terrestrial tortoises in South America and is thought to disperse large seeds. However, little is known about their role as seed dispersers, and their potential use as restorers of defaunated areas. Here, we assessed the maximum width of seeds this species could ingest, the mean gut retention time (GRT), and the post-consumption germination capacity for tropical fruit species. Forty different fruit species were offered to eight captive individuals, obtaining a maximum seed width swallowed of 23 mm. We used four native plant species to measure the GRT within four tortoises, and we found a mean retention time of 18.92 ± 4.81 days. We also found that sex is an important indicator of GRT, with females presenting longer retention periods. This novel finding may be due to the higher metabolic defecating and dispersing rates of males. Although germination proportions varied between the four plant species used in the experiment, overall defecated seeds germinated faster than control seeds. We conclude that red-footed tortoises are potentially important seed dispersers due to their ability to swallow a large quantity and size of seeds while accelerating seed germination rates. This species should be considered a viable ecological substitute for large frugivores in rewilding projects, as C. carbonaria performs similar functions to large dispersers that have been extirpated due to defaunation processes. • Chelonoidis carbonaria individuals could ingest a maximum seed width of 23 mm. • The mean gut retention time within four captive tortoises was 18.92 ± 4.81 days. • Females of C. carbonaria present longer gut retention times than males. • Defecated seeds germinated faster than control seeds. [ABSTRACT FROM AUTHOR]

An often-overlooked question of the biodiversity crisis is how natural hazards contribute to species extinction risk. To address this issue, we explored how four natural hazards, earthquakes, hurricanes, tsunamis, and volcanoes, overlapped with the distribution ranges of amphibians, birds, mammals, and reptiles that have either narrow distributions or populations with few mature individuals. To assess which species are at risk from these natural hazards, we combined the frequency and magnitude of each natural hazard to estimate their impact. We considered species at risk if they overlapped with regions where any of the four natural hazards historically occurred (n = 3,722). Those species with at least a quarter of their range subjected to a high relative impact were considered at high risk (n = 2,001) of extinction due to natural hazards. In total, 834 reptiles, 617 amphibians, 302 birds, and 248 mammals were at high risk and they were mainly distributed on islands and in the tropics. Hurricanes (n = 983) and earthquakes (n = 868) affected most species, while tsunamis (n = 272), and volcanoes (n = 171) affected considerably fewer. The region with the highest number of species at high risk was the Pacific Ring of Fire, especially due to volcanoes, earthquakes, and tsunamis, while hurricane-related high-risk species were concentrated in the Caribbean Sea, Gulf of Mexico, and northwestern Pacific Ocean. Our study provides important information regarding the species at risk due to natural hazards and can help guide conservation attention and efforts to safeguard their survival. [ABSTRACT FROM AUTHOR]

Biodiversity inventories contain important information about species richness, community structure, and composition, and are the first step in developing any conservation and mitigation strategies. The Atlantic Forest of South America is home to around 334 species of small‐, medium‐, and large‐sized mammals, and is currently restricted to less than 12% of its original cover. Here, we present the ATLANTIC MAMMALS, an open data set on information on medium‐ and large‐sized mammal assemblages in the Atlantic Forest of Brazil, Paraguay, and Argentina. A total of 129 studies were compiled, including published and in press peer‐reviewed papers, book chapters, theses and unpublished data. We mapped 244 assemblages, eight orders, 63 genera, and 94 species (24 of which are classified as threatened by the IUCN Red List) distributed in 128 protected and 116 unprotected areas. Species richness of the mammalian assemblages varied from 1 to 39 species (mean 15). The most recorded species in the entire biome was Dasypus novemcinctus, followed by Cerdocyon thous and Procyon cancrivorous. These data can be useful in support of macroecological studies and conservation planning strategies. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. [ABSTRACT FROM AUTHOR]