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Aim Every spring endangered Mexican long-nosed bats ( Leptonycteris nivalis) migrate up to 1200 km from central Mexico to southern United States. Evidence suggests that L. nivalis follows the blooms of paniculate agave plants (genus Agave, subgenus Agave). Paniculate agave inflorescences are adapted to attract bats, and studies have indicated that Leptonycteris spp. played a key role in Agave speciation. We test the hypothesis of the Agave migratory corridor by (1) modelling the distribution of the relevant Agave species; and (2) testing whether bat records are significantly related to Agave species richness as predicted by our models. Location Mexico and United States. Methods We selected nine paniculate Agave species based on a set of criteria and modelled the current distribution of those species using maxent and the Genetic Algorithm for Rule-set Production (GARP), and geographic information systems to analyse the spatial correspondence of Agave richness and presence of L. nivalis. Results We combined the Agave presence maps that resulted from the models with higher performance to create a richness map. This map indicated up to five species overlapping. L. nivalis occurrence areas correspond with areas with two, three and four Agave species more often than random expectations at the 0.05 significance level. The opposite is observed for areas with 0 Agave species where L. nivalis correspond less often than random. Main conclusions Presence-pseudo-absence and presence-background modelling tools allowed us to map potential Agave presence. These maps could guide conservation actions to ensure the maintenance of this pollination corridor. Areas with higher number of Agave species are distributed along mountain chains and may provide foraging resources for L. nivalis for longer period of time during its migration. We recommend implementing a long-term monitoring programme in those areas to document inflorescence timing in Agave species and the presence of L. nivalis. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Climate change has significant impacts on the distribution of species and alters ecological processes that result from species interactions. There is concern that such distribution shifts will affect animal-plant pollination networks. We modelled the potential future (2050 and 2070) distribution of an endangered migratory bat species (Leptonycteris nivalis) and the plants they pollinate (Agave spp) during their annual migration from central Mexico to the southern United States. Our models show that the overlap between the Agave and the endangered pollinating bat will be reduced by at least 75%. The reduction of suitable areas for Agave species will restrict the foraging resources available for the endangered bat, threatening the survival of its populations and the maintenance of their pollination service. The potential extinction of the bat L. nivalis will likely have negative effects on the sexual reproduction and genetic variability of Agave plants increasing their vulnerability to future environmental changes. [ABSTRACT FROM AUTHOR]

Wildlife conservation involves making management decisions with incomplete knowledge of ecological relationships. Efforts to augment foraging resources for the endangered Mexican long‐nosed bat (Leptonycteris nivalis) are progressing despite limited knowledge about the species' foraging behavior and requirements. This study aimed to understand L. nivalis responses to floral resource availability, focusing on individual agave‐ and local‐scale characteristics influencing visitation rates to flowering agaves. We observed bat visitation at 62 flowering agaves around two roosts in northeast Mexico on 46 nights in the summers of 2017 and 2018. We found visitation rate had positive relationships with two agave‐scale characteristics: the number of umbels with open flowers and the lower vertical position on the stalk of those umbels (i.e., earlier phenological stages of flowering). However, these factors exhibited strong negative interaction: with few umbels with open flowers, the position of flowering umbels had little effect on visitation rate, but when umbels with open flowers were abundant, visitation rate was more strongly related to the lower flowering umbel position. We also found relationships between visitation rate and two local‐scale characteristics: negative for the density of flowering conspecifics within 30 m of the focal agave and positive for the density of dead standing agave stalks within 30 m. Our findings suggest opportunities to augment foraging resources for L. nivalis in ways that are consistent with their foraging behavior, including: increasing the supply of simultaneously blooming flowers by planting agave species that tend to have more umbels with simultaneously open flowers; planting multiple species of agaves with different flowering times to increase the availability of agaves with open flowers on lower‐positioned umbels throughout the period when bats are present in the region; planting agaves in clusters; and keeping dead standing agave stalks on the landscape. Our study points to useful management strategies that can be implemented and monitored as part of an adaptive management approach to aid in conservation efforts. [ABSTRACT FROM AUTHOR]

Societal Impact Statement Crop wild relatives (CWR) are plant taxa closely related to crops and are a source of high genetic diversity that can help adapt crops to the impacts of global change, particularly to meet increasing consumer demand in the face of the climate crisis. CWR provide vital ecosystem services and are increasingly important for food and nutrition security and sustainable and resilient agriculture. They therefore are of major biological, social, cultural and economic importance. Assessing the extinction risk of CWR is essential to prioritise in situ and ex situ conservation strategies in Mesoamerica to guarantee the long‐term survival and availability of these resources for present and future generations worldwide. Summary: Ensuring food security is one of the world's most critical issues as agricultural systems are already being impacted by global change. Crop wild relatives (CWR)—wild plants related to crops—possess genetic variability that can help adapt agriculture to a changing environment and sustainably increase crop yields to meet the food security challenge.Here we report the results of an extinction risk assessment of 224 wild relatives of some of the world's most important crops (i.e. chilli pepper, maize, common bean, avocado, cotton, potato, squash, vanilla and husk tomato) in Mesoamerica—an area of global significance as a centre of crop origin, domestication and of high CWR diversity.We show that 35% of the selected CWR taxa are threatened with extinction according to The International Union for Conservation of Nature (IUCN) Red List demonstrates that these valuable genetic resources are under high anthropogenic threat. The dominant threat processes are land use change for agriculture and farming, invasive and other problematic species (e.g. pests, genetically modified organisms) and use of biological resources, including overcollection and logging. The most significant drivers of extinction relate to smallholder agriculture—given its high incidence and ongoing shifts from traditional agriculture to modern practices (e.g. use of herbicides)—smallholder ranching and housing and urban development and introduced genetic material.There is an urgent need to increase knowledge and research around different aspects of CWR. Policies that support in situ and ex situ conservation of CWR and promote sustainable agriculture are pivotal to secure these resources for the benefit of current and future generations. [ABSTRACT FROM AUTHOR]

The diverse functional roles of over 6,000 species of extant mammals that range in body size across eight orders of magnitude, from blue whales (Balaenoptera musculus) to tiny Etruscan shrews (Suncus etruscus), contribute to shaping Earth's ecosystems. Large mammalian herbivores (e.g. African elephants [ Loxodonta africana ], American bison [ Bison bison ], hippopotamuses [ Hippopotamus amphibius ]) and carnivores (e.g. wolves [ Canis lupus ], pumas [ Puma concolor ], sea otters [ Enhydra lutris ]) often have significant effects on primary producers in terrestrial, aquatic, and marine systems through nutrient cycling, energy flow, and the exertion of bottom-up and top-down processes. Small mammals, like bats, are important pollinators, dispersers of fruits, and consumers of arthropods, and others, especially rodents and primates, are important predators and dispersers of seeds. Many of these mammal-mediated processes occur simultaneously in the same ecosystem, and have significant effects on community structure of primary producers that in turn alter communities of other vertebrates and invertebrates. Many mammals also are ecosystem engineers (e.g. elephants, American beavers [ Castor canadensis ], porcupines [ Erithezon dorsatum ], prairie dogs [ Cynomys spp.]) that create, significantly modify, or destroy habitat, and by doing so, they alter ecosystem structure and function and increase habitat heterogeneity and biodiversity. The extensive influence mammals have on ecosystems results in important services that contribute to human well-being, such as pollination, insect pest control, and bioturbation of soils. The rapid declines in abundance of many mammal populations and the associated increase in extinction risk raise conservation concerns for mammals. To maintain mammalian diversity and the critical ecosystem processes they provide, scientists need to mobilize concern for their status and strive for more effective and comprehensive conservation action. We provide insights and synthesis on the ecological role of mammals and highlight key research questions and future directions for their conservation. [ABSTRACT FROM AUTHOR]