We are currently living through a major global extinction event, with the loss of species occurring at a rate faster than seen for several millennia. While previous extinction episodes have been caused by massive planetary changes such as volcanic explosions or shifts in tectonic plates, the current die-off is almost entirely driven by the activities of man.
The last global extinction event was 65 million years ago and led to the extinction of the dinosaurs and a permanent re-shaping of life on earth. It now appears that a similar wave of extinction is gathering pace across the planet.
“Palaeontologists characterize mass extinctions as times when the Earth loses more than three-quarters of its species in a geologically short interval, as has happened only five times in the past 540 million years or so. Biologists now suggest that a sixth mass extinction may be under way, given the known species losses over the past few centuries and millennia”. Barnosky 2011
As humans we have vastly changed and manipulated our environments at the cost of other living organisms such that we are now stood at a tipping point, where we can either continue accepting this decline, or instead use our knowledge and capabilities to halt the loss of global biodiversity.
“The current massive degradation of habitat and extinction of species is taking place on a catastrophically short timescale, and their effects will fundamentally reset the future evolution of the planet's biota. The fossil record suggests that recovery of global ecosystems has required millions or even tens of millions of years.” Michael J Novacek, 2001.
Current predictions suggest that if we continue on our current trajectory we are likely to lose half of all known species on earth within the next century.
Nearly a quarter of the world's mammals, a third of amphibians and at least a tenth of bird species are currently threatened with extinction. Climate change alone is expected to force a further 30% of species to the brink of extinction within the next 50 years.
Many of these rare species may appear to not have any obvious benefits to us, or provide us with any direct ecosystem service. Their rarity alone has meant that few other organisms rely upon them. Yet diverse ecosystems are known to be far more resilient to change and perturbations than ecosystems supporting only a limited assemblage of species. A single link in a spider’s web may not perform a specific function in isolation, but the links altogether provide the web with strength and stability. If enough links are lost however the entire web will collapse in the slightest gust of wind. Humans are as intrinsically part of this web as any other organism on the planet.
“We should not in any way feel complacent that we are not on the list of possible extinctions” Richard Leakey.
In the UK over 900 native species are currently classed as a conservation priority, with several hundreds more known to be in significant decline. The countryside is now silent of many species which were once a familiar sight even as recent as only a generation ago.
Each year several millions are spent on conservation, and yet rare species are still slipping through the net.
“In 2002, world leaders committed, through the Convention on Biological Diversity, to achieve a significant reduction in the rate of biodiversity loss by 2010.... Our analyses suggest that biodiversity has continued to decline over the past four decades...the rate of biodiversity loss does not appear to be slowing” Butchart et al 2010.
Many rare species, given the right conditions, can thrive and are in fact extremely successful at expanding their populations. Wild poppy plants are a key example of this; hidden from view for decades and surviving only as seeds in the ground the moment small patches of land are not sprayed with herbicide they can flourish in huge numbers. Huge resources are therefore not always required to prevent species decline. By identifying and managing the specific pressures they face, whether this be habitat degradation or manipulation by man, these species can be released from their ongoing decline.
When habitats are successfully restored the knock on effects can be huge – a pond cleared out to support a rare stonewort becomes a haven for breeding damselflies, a hay meadow managed for a rare orchid can start to support rare ground nesting birds. And healthy functioning ecosystems have almost incalculable value to humans.
Human beings have an unparalleled ability to show compassion for life and empathy with living things – it is time to use our knowledge and wisdom to save the planet for the next generation.