Dave Bishop, author of an excellent report on Manchester’s biodiversity, reflects on what we are doing. (This is NOT a cheerful blogpost.)
New Report on Biodiversity Loss
A new report from the Zoological Society of London (http://www.livingplanetindex.org/home/index) suggests that the global loss of non-human species is even worse than previously thought. Two years ago the same organisation estimated that wildlife was down “only” around 30%.But the authors of this latest report have applied improved statistical analyses to the data which have led them to the more depressing conclusion that populations of mammals, birds, reptiles, amphibians and fish have declined by an average of 52%.
Populations of freshwater species have suffered an even worse fall of 76%.
Nevertheless, it is clear that, whatever the true extent of the losses, they are being driven by human activity – particularly unsustainable human consumption.
The society’s report, in conjunction with the pressure group WWF, says humans are cutting down trees more quickly than they can re-grow, harvesting more fish than the oceans can re-stock, pumping water from rivers and aquifers faster than rainfall can replenish them, and emitting more carbon than oceans and forests can absorb.
The index tracks more than 10,000 vertebrate species populations from 1970 to 2010. It reveals a continued decline in these populations and the global trend does not appear to be slowing down.
In the UK, the government promised to halt wildlife decline – but populations of our wild species continue to fall.
Articles in the press, and other media, about this report have emphasised wildlife losses in the developing world and particularly the losses of big, ‘glamorous’ species such as elephants, lions and tigers. But as noted above wildlife continues to decline in the UK too – including in the South Manchester suburb of Chorlton-cum-Hardy where I live!
For example, when I first knew the Mersey Valley, around 40 years ago, there was a flourishing population of Brown Hares – now all gone, probably because there are too many dogs which chase and harass them. In fact Brown Hares are endangered all over Greater Manchester and the GM Ecology Unit have an on-going project which seeks to conserve them (http://gmwildlife.org.uk/wildlife/species/index.php?species=European%20Brown%20Hare&zoom_highlightsub=hares).
There used to be a population of Water Voles on Chorlton Brook but they have gone too – especially since the Environment Agency brutally and insensitively canalised the brook a few years ago. The Water Vole is supposed to be a protected species because it is Britain’s fastest declining wild mammal and is classed as a Priority Species in the UK Biodiversity Action Plan (http://www.wildlifetrusts.org/species/water-vole).
Also lost, along with the Water Vole habitat, was our only local specimen of Hard Fern. Now that might not mean much to most people but being an amateur botanist, it’s the losses of plant species that I notice most. Hard Fern may not be rare nationally but, as far as I can tell, it now appears to be extinct in Chorlton.
Not far from Chorlton Brook there used to be a smallish grassland site with a rich array of wild flowers growing on it. One of these was a curious little Buttercup which it took me ages to identify. Finally, I pinned it down to something called Hairy Buttercup (yeah, yeah, yeah – amusing name) – which is quite an uncommon species nationally. I later discovered that several other local botanists had noted it, independently of me. Then the local authorities, in their ‘wisdom’, decided to plant trees on the site (tree planting is a goooood, grrreeeen thing to do … isn’t it?) and the population of Hairy Buttercup was destroyed in the process. The Vice County Plant Recorder tells me that he believes that Hairy Buttercup is now extinct in the whole of South Lancashire.
My favourite botanical site, in the Mersey Valley, was Lower Hardy Farm (on the Chorlton side of the Mersey, diagonally opposite Jackson’s Boat). It was on that site that I made one of my best finds – a plant called Crowberry. That find was remarkable because Crowberry is usually thought of as a plant of upland moors – not lowland river valleys. But soon after I found it, about 30 years ago, it was destroyed by teenage motorcycle scramblers.
More recently, the Lower Hardy Farm site has been destroyed by the Metrolink-to-the-airport bridge and we have lost, among other species, Royal Fern, Wood Club-rush and two unusual species of Hawkweed.
A bit further up the river, near Chorlton Water Park, was a single specimen of an old hay meadow species called Pale Lady’s Mantle. This was several yards from a small sub-station owned by a utilities company. One day they decided to spray the whole area with herbicide and the Lady’s Mantle was destroyed (it posed no threat to the sub-station whatsoever!). I subsequently found another specimen near West Didsbury – but that site is now so overgrown that it is highly likely that Pale Lady’s Mantle too is extinct locally.
Then there was a small population of Ivy-leaved Duckweed, growing in a flooded section of the old railway line between Chorlton and Old Trafford, but that too has been lost to Metrolink.
And there was the little colony of Pignut, with attendant Cuckooflowers, which used to grow on the patch of ground in front of Chorlton Precinct, and used to grace sunny mornings in May and June as I waited for my bus to work. That has long gone – probably the victim of over-zealous mowing at the wrong time of year. I’ve not found Pignut anywhere else in Chorlton – so that’s probably extinct here too.
And so on and so on.
Years ago I decided to specialise in plants, because plants are my first love, but other local naturalists study bats, birds, butterflies and moths and other insects and invertebrates and fungi. I’m sure that they too could supply similar ‘litanies of loss’.
And remember, there’s probably nothing unique about Chorlton. This steady, relentless erosion of our natural capital is happening day in day out, year in year out all over the UK and all over the world. None of the species I have mentioned above have been completely eliminated from the UK, as a whole (yet!), but these days, once common species are having an increasing tendency to become rare as they are snuffed out in parish after parish after parish.
Of course, our culture regards the ‘weeds and bugs’ that we share the planet with as, at best, trivial and irrelevant and, at worst, as nuisances that need to be exterminated. But our culture needs to wake up to the fact that our own species almost certainly couldn’t survive in a completely sterilised environment.
Finally, it’s the timeframe within which this destruction is happening which is truly, truly terrifying. A few months ago I reviewed Elizabeth Kolbert’s book on ‘The Sixth Extinction’. The author of that book noted that it is now, more or less, agreed that when humans migrated out of Africa, some 100,000 years ago, they exterminated large animals (mammoths, giant ground sloths, moas etc.) everywhere they went. Kolbert interviewed a paleobiologist, named John Alroy, who described this ‘megafauna extinction’ as a “geologically instantaneous ecological catastrophe too gradual to be perceived by the people who unleashed it.”
But this latest phase of the on-going, human induced, ecological catastrophe is happening so fast that it’s perceptible well within a single human life-time. As I’ve detailed above, I have witnessed extinction events happening on my local patch, in my life-time; and my life-time is but an infinitesimal fraction of a geological eye blink!
Dave Bishop, October 2014