What's Going On?

Although this blog is intended to discuss the impact of global biodiversity loss on humans, I want to begin by outlining the reverse, the impact we are having on the natural world. To assess this,  I will draw from data and discussions taken from the 2014 Living Planet Report I mentioned below, in particular the Living Planet Index (LPI).

The index is calculated using trends in 10,380 populations of over 3,038 vertebrates to estimate the number of species in different taxonomic groups and biogeographic realms over time. For the first time the data is then weighted as population trends for each group and realm in the database are not perfect representations of number and distribution worldwide. For example, without weighting the LPI over represents trends in Europe and under represents reptiles. This results in the LPI-D. 

Each population time series is then assigned to one of five biogeographic realms (Nearctic, Neotropical, Palearctic, Afrotropical and Indo-Pacific) and classified as to whether the population is predominantly terrestrial, freshwater or marine. As a result, it is possible to compare how different species are doing in different biomes and regions. 

Global LPI

Declining or Stable Populations

The global LPI can be separated into temperate and tropical regions. The results indicate a global decline f 52% vertebrate populations since the 1970s with the average decline greater in the tropics (56% decline in tropics, 36% decline in temperate regions). 

The main threats to each population are also recorded with the results displayed below. 

Threats

The LPI-D provides a fairly comprehensive overview of the state of vertebrate species worldwide, however I feel that in order to understand the true health of global ecosystems and the impact of human populations, plant and invertebrate biodiversity should be taken into account. Due to the inherent nature and sheer number of species this is obviously near impossible using the techniques developed by the LPI-D so particular proxies could be employed.

Despite this flaw, hopefully the shocking statistics should kickstart new dialogues and action to preserve what we have left.

Access to the PDF can be found here: http://wwf.panda.org/about_our_earth/all_publications/living_planet_report/