Biodiversity: The ravages of guns, nets and bulldozers

Abstract

© 2 0 1 6 M a c m i l l a n P u b l i s h e r s L i m i t e d , p a r t o f S p r i n g e r N a t u r e . A l l r i g h t s r e s e r v e d .risk -have guided assessments, now for 82,845 species. Assessors assign species to categories, including 'near-threatened' , 'vulnerable' , 'endangered' or 'critically endangered' depending on their population size; past, current and projected population trends; geographic range and other symptoms of extinction risk. Species in the latter three groups are collectively referred to as 'threatened' .To assess the relative prevalence of current hazards to biodiversity, we quantified threat information for 8,688 near-threatened or threatened species belonging to species groups in which all known species have been assessed (for complete list of taxa included, see Supplementary Information; go.nature.com/2ajen88).The basic message emerging from these data is that whatever the threat category or species group, overexploitation and agriculture have the greatest current impact on biodiversity (see 'Big killers').Of the species listed as threatened or near-threatened, 72% (6,241) are being overexploited for commerce, recreation or subsistence. The Sumatran rhinoceros (Dicerorhinus sumatrensis), Western gorilla (Gorilla gorilla) and Chinese pangolin (Manis penta dactyla, a scaly mammal), for instance, are all illegally hunted as a result of high market demand for their body parts and meat. These are just three of the more than 2,700 species affected by hunting or fishing, or by people collecting live specimens for the pet trade. At the same time, unsustainable logging is contributing to the decline of more than 4,000 forest-dependent species, such as the Bornean wren-babbler (Ptilocichla leucogrammica), India's Nicobar shrew (Crocidura nicobarica), and the Myanmar snub-nosed monkey (Rhinopithecus strykeri).The expansion and intensification of agricultural activity is imperilling 5,407 species -62% of those listed as threatened or near-threatened. Africa's cheetah (Acinonyx jubatus), Asia's hairy-nosed otter (Lutra sumatrana) and South America's huemul deer (Hippocamelus bisulcus) are among more than 2,300 species affected by livestock farming and aquaculture. And the Fresno kangaroo rat (Dipodomys nitratoides) and the African wild dog (Lycaon pictus) are two of more than 4,600 species currently under threat from land modification associated with the production of food, fodder or fuel crops.Meanwhile, anthropogenic climate change -including increases in storms, flooding, extreme temperatures or drought that exceed background variability, as well as sea-level rise -is currently affecting 19% of species listed as threatened or near-threatened. Hooded seals (Cystophora cristata) are among the 1,688 species affected. These have dropped in abundance by 90% in the northeastern Atlantic Arctic over the past few decades More than 80% of species analysed are harmed by more than one sub-class threat. OVER-EXPLOITATION BIG KILLE SOverexploitation and agriculture are the most prevalent threats faci...

A comparison of camera trap and permanent recording video camera efficiency in wildlife underpasses

“…Habitat fragmentation is one of the three main causes of biodiversity loss over the last decades (Maxwell, Fuller, Brooks, & Watson, 2016). It affects all taxonomic groups and has numerous consequences.…”

“…Roads have a specific impact and cause wide‐ranging damage to ecosystems, ranking in the top 10 threats to biodiversity (Maxwell et al., 2016). In the short and/or long term, roads increase local extinction risk through wildlife–vehicle collisions, lead to further habitat loss due to associated land consolidation, deteriorate habitats along the roadside, decrease population abundance (avoidance phenomenon), and reduce genetic flows by creating a filter and barrier effect.…”

Palmiers à huile et biodiversité: analyse de la situation par le Groupe de travail de l’UICN sur les palmiers à huile

“…Le biote de notre planète est menacé par l'ampleur et la rapidité du changement climatique (194), et les chercheurs lui attribuent déjà certaines extinctions locales (195,196). …”

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“…There are concerns that populations of many wildlife species in NNR, which had been steadily increasing since the end of the civil war, are being impacted by increasing human pressure (Grossmann et al, 2014). Anthropogenic conversion of intact vegetation, or habitat loss, is one of the major drivers of species extinctions globally (Maxwell et al, 2016;Fischer & Lindenmayer, 2007), followed closely by overhunting (Maxwell et al, 2016;Tranquilli et al, 2014), both of which pose an immediate threat to NNR's biodiversity and are a major challenge for NNR's management. Accurately monitoring fine scale spatial and temporal trends in land-use and tree-cover is increasingly used for monitoring the ecological state of important conservation areas (Tracewski et al, 2016;Nagendra et al, 2013;Allan et al, 2017).…”