Large Old World Fruit Bats on the Brink of Extinction: Causes and Consequences

peer reviewedLarge Old World fruit bats (LOWFBs), species of Pteropus, Acerodon, and related genera of large bats in the pteropodid subfamily Pteropodinae, play important roles as agents of dispersal and pollination across the Paleotropics. LOWFBs are also collectively the most threatened group of bats in the world, with 71% of extant species assessed as threatened by International Union for Conservation of Nature. As highlighted here, contrary to other bats, the vast majority of LOWFBs face multiple simultaneous threats. Most importantly, biological and ecological traits, in particular life history characteristics, diet, movement, social ecology, and physiology, intensify threats and accelerate species declines. Furthermore, we demonstrate that LOWFBs are to be considered keystone species and express concern about the erosion of this role and the cascading effects expected on native ecosystems. In response to this alarming situation, we advance general recommendations and identify overarching research and conservation actions

Terrestrial invasion of pomatiopsid gastropods in the heavy-snow region of the Japanese Archipelago

<p>Abstract</p> <p>Background</p> <p>Gastropod mollusks are one of the most successful animals that have diversified in the fully terrestrial habitat. They have evolved terrestrial taxa in more than nine lineages, most of which originated during the Paleozoic or Mesozoic. The rissooidean gastropod family Pomatiopsidae is one of the few groups that have evolved fully terrestrial taxa during the late Cenozoic. The pomatiopsine diversity is particularly high in the Japanese Archipelago and the terrestrial taxa occur only in this region. In this study, we conducted thorough samplings of Japanese pomatiopsid species and performed molecular phylogenetic analyses to explore the patterns of diversification and terrestrial invasion.</p> <p>Results</p> <p>Molecular phylogenetic analyses revealed that Japanese Pomatiopsinae derived from multiple colonization of the Eurasian Continent and that subsequent habitat shifts from aquatic to terrestrial life occurred at least twice within two Japanese endemic lineages. Each lineage comprises amphibious and terrestrial species, both of which are confined to the mountains in heavy-snow regions facing the Japan Sea. The estimated divergence time suggested that diversification of these terrestrial lineages started in the Late Miocene, when active orogenesis of the Japanese landmass and establishment of snowy conditions began.</p> <p>Conclusions</p> <p>The terrestrial invasion of Japanese Pomatiopsinae occurred at least twice beside the mountain streamlets of heavy-snow regions, which is considered the first case of this event in the area. Because snow coverage maintains stable temperatures and high humidity on the ground surface, heavy-snow conditions may have paved the way for these organisms from freshwater to land via mountain streamlets by preventing winter desiccation in mountain valleys. The fact that the terrestrialization of Pomatiopsidae occurred only in year-round wet environments, but not in seasonally dried regions, provides new insight into ancient molluscan terrestrialization.</p

Threats to environmentally sensitive areas from peri-urban expansion in Mauritius

There are 60 inhabited tropical island countries covering c. 3.54 million km2 of land. Tropical islands are disproportionately rich in endemic plants, birds, molluscs, and other invertebrates (Whittaker and Fernandez-Palacios 2007) relative to similar mainland habitats (see, for example, Kier et al. 2009). The majority of global coral and seagrass diversity is located in the reefs, shoals, and lagoons of tropical islands (Spalding et al. 2001, 1997), the islands accounting for 2.4% of the global land area, but housing a much greater swathe of the Earth's biological uniqueness (Kreft et al. 2008). At the same time, the topography of most tropical islands is relatively steep, compressing their high terrestrial and coastal marine biological value into relatively small areas. This compression also reduces the average size of watersheds and shortens river main stems, in particular relative to the hydrological space of continental systems (Milliman et al. 1999). Consequently, island nations rely heavily on groundwater extraction and river impoundments to provide clean water to urban areas, particularly during periods of low rainfall

Monitoring hunted species of cultural significance: Estimates of trends, population sizes and harvesting rates of flying-fox (Pteropus sp.) in New Caledonia

International audienceAssessing population trends and their underlying factors is critical to propose efficient conservation actions. This assessment can be particularly challenging when dealing with highly mobile, shy and nocturnal animals such as flying-foxes. Here we investigated the dynamics of hunted populations of Pteropus ornatus and P. tonganus in the Northern Province of New Caledonia. First, an ethno-ecological survey involving 219 local experts identified 494 flying-fox roosts. Current status was assessed for 379 of them, among which 125 were no longer occupied, representing a loss of 33% over ca. 40 years. Second, species-specific counts conducted at 35 roosts, and a sample of animals killed by hunters, revealed that the endemic species, P. ornatus, was dominant (68.5%). Between 2010 and 2016, 30 roosts were counted annually during the pre-parturition period. Roosts size averaged 1,425 ± 2,151 individuals (N = 180 counts) and showed high among-year variations (roost-specific CV = 37-162%). If we recorded significant inter-annual variation, we did not detect a significant decline over the 7-yr period, although one roost went possibly extinct. Population size of the two species combined was estimated at 338,000−859,000 individuals distributed over ca. 400 roosts in the Northern Province. Flying-foxes are popular game species and constitute traditional food for all communities of New Caledonia. Annual bags derived from a food survey allowed us to estimate harvesting rates at 5-14%. Such a level of harvesting for species with a 'slow' demography, the occurrence of poaching and illegal trade, suggest the current species use might not be sustainable and further investigations are critically needed. PLOS ONE | https://doi.org/10.1371/journal.pone