16 research outputs found
The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
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The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts
Biodiversity continues to decline in the face of increasing anthropogenic pressures
such as habitat destruction, exploitation, pollution and introduction of
alien species. Existing global databases of species’ threat status or population
time series are dominated by charismatic species. The collation of datasets with
broad taxonomic and biogeographic extents, and that support computation of
a range of biodiversity indicators, is necessary to enable better understanding of
historical declines and to project – and avert – future declines. We describe and
assess a new database of more than 1.6 million samples from 78 countries representing
over 28,000 species, collated from existing spatial comparisons of
local-scale biodiversity exposed to different intensities and types of anthropogenic
pressures, from terrestrial sites around the world. The database contains
measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35)
biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains
more than 1% of the total number of all species described, and more than
1% of the described species within many taxonomic groups – including flowering
plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans
and hymenopterans. The dataset, which is still being added to, is
therefore already considerably larger and more representative than those used
by previous quantitative models of biodiversity trends and responses. The database
is being assembled as part of the PREDICTS project (Projecting Responses
of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk).
We make site-level summary data available alongside this article. The full database
will be publicly available in 2015
West Africa - a safe haven for frogs? A sub-continental assessment of the Chytrid Fungus (Batrachochytrium dendrobatidis)
A putative driver of global amphibian decline is the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd). While Bd
has been documented across continental Africa, its distribution in West Africa remains ambiguous. We tested 793 West
African amphibians (one caecilian and 61 anuran species) for the presence of Bd. The samples originated from seven West
African countries - Be´nin, Burkina Faso, Coˆ te d’Ivoire, Ghana, Guinea, Liberia, Sierra Leone - and were collected from a variety
of habitats, ranging from lowland rainforests to montane forests, montane grasslands to humid and dry lowland savannahs.
The species investigated comprised various life-history strategies, but we focused particularly on aquatic and riparian
species. We used diagnostic PCR to screen 656 specimen swabs and histology to analyse 137 specimen toe tips. All samples
tested negative for Bd, including a widespread habitat generalist Hoplobatrachus occipitalis which is intensively traded on
the West African food market and thus could be a potential dispersal agent for Bd. Continental fine-grained (30 arc seconds)
environmental niche models suggest that Bd should have a broad distribution across West Africa that includes most of the
regions and habitats that we surveyed. The surprising apparent absence of Bd in West Africa indicates that the Dahomey
Gap may have acted as a natural barrier. Herein we highlight the importance of this Bd-free region of the African continent -
especially for the long-term conservation of several threatened species depending on fast flowing forest streams (Conraua
alleni (‘‘Vulnerable’’) and Petropedetes natator (‘‘Near Threatened’’)) as well as the ‘‘Critically Endangered’’ viviparous toad
endemic to the montane grasslands of Mount Nimba (Nimbaphrynoides occidentalis).http://www.plosone.org
West Africa - A Safe Haven for Frogs? A Sub-Continental Assessment of the Chytrid Fungus (Batrachochytrium dendrobatidis)
A putative driver of global amphibian decline is the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd). While Bd has been documented across continental Africa, its distribution in West Africa remains ambiguous. We tested 793 West African amphibians (one caecilian and 61 anuran species) for the presence of Bd. The samples originated from seven West African countries - Bénin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea, Liberia, Sierra Leone - and were collected from a variety of habitats, ranging from lowland rainforests to montane forests, montane grasslands to humid and dry lowland savannahs. The species investigated comprised various life-history strategies, but we focused particularly on aquatic and riparian species. We used diagnostic PCR to screen 656 specimen swabs and histology to analyse 137 specimen toe tips. All samples tested negative for Bd, including a widespread habitat generalist Hoplobatrachus occipitalis which is intensively traded on the West African food market and thus could be a potential dispersal agent for Bd. Continental fine-grained (30 arc seconds) environmental niche models suggest that Bd should have a broad distribution across West Africa that includes most of the regions and habitats that we surveyed. The surprising apparent absence of Bd in West Africa indicates that the Dahomey Gap may have acted as a natural barrier. Herein we highlight the importance of this Bd-free region of the African continent - especially for the long-term conservation of several threatened species depending on fast flowing forest streams (Conraua alleni (“Vulnerable”) and Petropedetes natator (“Near Threatened”)) as well as the “Critically Endangered” viviparous toad endemic to the montane grasslands of Mount Nimba (Nimbaphrynoides occidentalis)
Map of confirmed records of <i>Bd</i> on the African continent (black dots).
<p>Grey transparent dots represent the West African localities with negative <i>Bd</i> records. The hollow black circles indicate <i>Bd</i> positive localities <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056236#pone.0056236-SotoAzat1" target="_blank">[87]</a> which were not used for modelling. The three red colours represent the geographical extent of three different models, predicting the potential distribution of <i>Bd</i>. Modelling is based on the conditions of sites with confirmed presence of the pathogen (light red = maximum; red = mean; dark red = minimum; for niche parameters see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056236#pone-0056236-t002" target="_blank">Table 2</a>).</p
Environmental parameters used in the environmental niche modelling (ENM) approach with a short description of the parameter and the source of the original data.
<p>Parameters 1–10, calculated in two steps: i) an average (from the years 1950 to 2000) for each month (January to February), thus leading to 12 averages; (ii) calculation as detailed in the main text. Parameters 11–12: calculated from the annual average of the year 2000. Parameters 13–15: extracted from the 500 m MODIS vegetation continuous fields dataset, which are derived from monthly composites that are in turn derived from eight day composites. All 7 bands were used and smoothed via a 4×4 rectangular neighbourhood function. Parameters 16–17: after calculation data were ln-transformed and multiplied by 10 to assure compatibility with other environmental parameters.</p
Detailed maps of West Africa.
<p>From top to bottom, depicting the most western positive records of <i>Bd</i> (black) and the negative records (transparent grey) (2a). <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056236#pone-0056236-g002" target="_blank">Figure 2b</a> indicates in white transparent lines the transport system (roads) of the region. If <i>Bd</i> is transported via humans, the area around Accra (Ghana) is most likely to be the point of introduction (well connected via transportation routes and highly suitable environment). Further shown (2c) are the extents of the potentially forest regions (green) with the Upper Guinea Forests west of the Dahomey Gap <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056236#pone.0056236-Burgess1" target="_blank">[after 131]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056236#pone.0056236-Daszak1" target="_blank">[2a]</a>. In 2d the known point localities of <i>Conraua alleni</i> (transparent yellow), <i>Petropedetes natator</i> (transparent blue) (light green = overlapping localities), and <i>Nimbaphrynoides occidentalis</i> (dark green) are depicted.</p
The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity