Part 2: Ecosystem Engineers

 

Last time I started to outline the kind of animals that lived in the UK before the last Ice Age, which we can consider a baseline of what would have lived in this country when the climate last resembled that of today. Most people are familiar with the Woolly Mammoth and other ice age fauna, which in warm periods have been confined to the high Arctic and dry grasslands in central Asia. South of them and in western Europe would have been animals that preferred woodland and warmer open country. Starting with the largest, the undoubted major influence on the habitats of Britain would have been elephants.

Seriously. The Straight-Tusked Elephant survived until only 30,000 years ago and lived in the temperate forest belt across the whole of Europe and Asia as far as Japan. Closely related to, but even larger than, the living African elephants, it would have opened up the forests, pushing over and eating trees, and creating a more parkland or open grassland habitat for other animals. This would have increased the variety of forest types – closed-canopy forest would not have been the only kind of woodland to be found, instead a mosaic of open grassland, small clearings and scrub would also have been found, with dense woodland perhaps more confined to steeper slopes where elephants found the going harder.

Narrow-Nosed Rhino

In addition to elephants, another surprising addition would have been rhinoceros. In fact, two species of temperate-climate rhino would have been found in the UK or northern Europe, the open country Narrow-nosed Rhino and the more forest loving Merck’s Rhinoceros.

Merck's Rhinoceros

 Both of these were large even for rhinos, as large as the Indian One-Horned Rhinoceros. Today their closest living relative is the Critically Endangered Sumatran Rhino, which has a total surviving population as low as 80 individuals.

Sumatran Rhino

 Although not as extensive an engineer of woodlands as elephants, they would still have created trails in the woodlands and affected the structure of grasslands by grazing. Another effect would have come about from most rhinoceros’ habits of using large dung piles for marking territory and social communication – the dung beetles and other insects these would attract would certainly have affected foraging by many bats, especially those that prefer beetles or gleaning from foliage along forest trails such as the Brown Long-Eared Bat.

Brown Long-Eared Bat

Perhaps the most unexpected animal of all to find in Britain though would have been the hippopotamus. Not just closely related, but the very same species to live in Africa’s rivers today, hippos only became extinct in Europe at the close of the last Ice Age when an unusually cold period even for an Ice Age eliminated the last populations in Spain and southern France. 

River Hippo

 In Africa they tend to create trampled grasslands up to 1km from the river, which would have impacted other animals in the waterways and coming down to drink. However, shallower rivers and streams would have been avoided, which would have left room for the last of the ecosystem engineers for this post, and the only one which so far has been reintroduced to the UK, the European Beaver.

Eurasian Beaver

Although a distinct species to the beavers of North America, their habits are identical and they would have greatly impacted wet woodlands, forest streams and the general hydrology of the land. This in turn would have affected fish, amphibians, waterside animals like the Water Vole and Otter, and their activities would have affected forest type and availability of nest sites for many birds.

Beaver dam, Scotland

Beavers have only been reintroduced to the UK in recent years but they are already having a big effect on how conservation of wetland and other areas is managed, although their impact on drainage of farmland and feeding on maize crops close to water has caused some issues. They are now starting to spread through the countryside away from the known sites, and recently they showed up at Longleat wildlife park under their own volition. As Longleat is one of the few collections in the UK to hold hippos, this means that England is now the only place on earth where hippos and beavers share the same waterways as they did in the Eemian.