This blog appeared on yesterday’s Woodland Trust blog , but I thought I would recycle it today.
A new approach to Forest “Management”
The Holocene Forest (which existed from around 10000 years before present to 7000 bp ) was a quiet place. The Wolves howled and the Aurochsen roamed between the trees (with the occasional tap tap of Mesolithic forest management), there was something missing – something really big. Something that had been present in every previous incarnation of Forest in every previous interglacial period in Northern Europe – Elephants. Straight-tusked Elephants, standing 4m tall at the shoulder and weighing in at 6-7 Tonnes. A monster.
Compare this with today’s African Savannah Elephants – 3.3m and 4-5 tonnes.
What would these leviathans of the Forest done and how would their daily activities affected the forest ecosystem?
Modern day African Forest Elephants (tiny by comparison with their extinct forebears) create permanent forest tracks and large clearings called Bai. Here they congregate for social life and also use them as salt licks where they find essential minerals which are otherwise rare.
Apart from creating forest tracks and clearings, what else might these Elephants have done in the forest. It seems likely that they would have ripped branches off trees and shrubs, to access leaves or fruit. Sometimes trees and small shrubs would have been pulled clean out of the ground or just knocked over, if they were in the way, or again to provide food. Would they have stripped bark from trees to eat in the winter? Without worrying too much about the details, it’s fair to say that Elephants would have made a big mess, knocked down lots of trees and ripped branches off the larger ones.
This might lead on to a debate about how much of the British forest in previous interglacials was kept open by Elephants, and provided open habitats such as grassland or heathland. But even without this debate, it’s worth considering the action of Elephants on Forest structure.
Our wildlife, including trees and shrubs, as well as species of open habitats, evolved hundreds of thousands or millions of years ago, under selective pressure from animals such as this huge Elephant. These species are still with us, even though the Elephants have gone. They continue to depend on the types of activity which those Elephants previously created.
Historic woodland management from the Mesolithic to the 19th century depended on coppicing, pollarding, hedging and grazing. Woodlands also encompassed muddy, flowery rides for moving animals, people, timber and wood. Together, these created conditions that equated very approximately to the conditions that the Elephants (and other animals) provided previously.
Can we do better at creating these conditions for purely conservation reasons? A machine, such as a digger with a back-hoe, on low pressure tires, could drive around a forest, randomly knocking trees and shrubs over and breaking branches off trees.
But it would not be able to mimic the prolific consumption of herbage by an Elephant, nor the creation of Elephant-sized dung heaps.
While it’s not really feasible (or ethical) to re-engineer a Straight Tusked Elephant from fossilised DNA, an alternative would be to create Robo-Tusker.
This would be superficially similar to the digger, but instead of being powered by fossil fuel, it would have an inbuilt anaerobic digestion/wood gasification plant – to “consume” the material it extracted from the forest. Instead of low pressure tyres it could have legs and slowly walk around the forest (walking robots have come on in leaps and bounds in recent years), until it’s power ran out and it needed to do some more digesting/gasifying. Instead of Elephant Dung it would produce high quality compost, as AD plants already do. It would need no driver – it would effectively be a self-controlled drone. And unlike wild Elephants it would have no desire to leave the forest in which it lived.
That will please the neighbours.
Thanks to George Monbiot for opening my eyes to the impact Elephants had on European Pleistocene Forests.
Rod Leslie formerly of the Forestry Commission left a comment on the WdT blog yesterday suggesting that we already had a good equivalent of Robo-Tusker – a Forest Harvester. But Rod missed the point – a harvester extracts timber. Robo-Tusker would only be a consumer in the sense of any other animal in the forest – except of course that it would not be able to produce mini Robo-tuskers. Now there’s a thought….