Impressive interactions

Recently I signed up for a three month volunteer placement at the Durrell Wildlife Conservation Trust in Jersey. This quickly evolved into a combined volunteer placement and research project. Food prep/feeding and enclosure cleaning dominate each day with just an hour or so for other tasks around the park. My research project will be on three aye-ayes kept at the park and this data collection will take place in the final weeks of my placement. The aim of this blog is simply to describe and show how Durrell is really doing all it can to make the world a friendlier place for wild animals; at ground level this is achieved by educating visitors about the animals that it keeps and providing representations of their natural habitats, which encourage natural behaviours.

Well, where do I start? Perhaps with two of the four species of non-human ape which have the most luxurious semi-naturalistic enclosures I have ever seen? Perhaps with the three species of tamarins that roam free in their exclusive unenclosed woods? Perhaps even with the aye-ayes – the animals that I will learn so much about in the coming year?

In fact, none of the above, instead I will start by introducing to you the two species of fruit bat that are kept at Durrell Wildlife Conservation Trust, namely the Livingstone's fruit bat and the Rodrigues fruit bat. The former can be found in the Comoros Islands in the Indian Ocean and is listed on the IUCN red list as endangered. The latter is endemic to Rodrigues; a single island also in the Indian Ocean and is listed as critically endangered – just one notch below being extinct in the wild.

The bats are housed in the conveniently named bat tunnel, which is constructed from all recycled materials; from unwanted plants and scraps of old astro-turf from a local hockey field, to off-cuts of wood and hundreds, if not thousands, of used car tyres. The methods that were employed and the materials that were utilised to build this enclosure demonstrate what can be achieved if sustainability is near the top of everyone’s agenda and recycling isn't thought of as being a modern fad that will fade away. Not only does the tunnel demonstrate that the sum of many recycled items is greater than each individual component, but it also shows that recycling can help save animal species in two ways; (1) it provides a safe home for the animals in captivity which provide a safety-net population if needed in any way; and (2) it shows that despite its size, no materials were drawn from the earth (wild habitats) for its construction and the materials that were used were not sent to a landfill to be put back into the earth! Everybody wins!

The tunnel simulates a tropical forest scene. It is comprised of a valley that runs the length of the enclosure (around 35 metres) and is just wide enough for a keeper to walk from one end to the other and feel the rush of wind flow from underneath the wings of the bats as the swoop (only just) overhead. The valley is about 1.5 metres below the other keeper-walking areas which run parallel on either side. These walkways are floored with strips of reclaimed astro-turf which is the perfect substrate for a floor which is constantly being messed, cleaned and kept harmful-bacteria-free. Separating the valley and the other walking areas are steep (40°) banks on either side made from the aforementioned recycled tyres and plants, which are watered daily. The walls of the tunnel are made from netting, attached to which are numerous food baskets and water stations. Draped throughout the tunnel are thick ropes, the type used for sports day tug-of-wars, which the bats enjoy clinging to whilst feeding!

The tunnel is kept extremely warm, averaging at a temperature around 27°C. It is important to maintain this temperature as the bats have bodily systems which are specially adapted to cope with the conditions. However, spending 1.5 hours each morning cleaning the floor and feeding apparatus is not a task undertaken lightly. The heat is generated by burning spare bits of wood from various projects around the park, which, I’m told has significantly reduced the energy bill of the mammal department.

Feeding takes place at 12.50 and around 17.00. To do this the feeder walks down the central valley, which encourages the bats to fly and walks back up each side of the tunnel in turn, placing food into the specially positioned baskets. Willow is occasionally used to supplement the normal diet and provide a form of enrichment.

Fruit bats have developed a technique of extracting as much usable content from food (energy, protein, etc.) without affecting their power-to-weight ratio too severely. After chewing a mouthful of food (either fruit and veg or special pellets) for a minute or two and all that can be obtained just through chewing has been obtained, a disc of mashed/chewed food is produced and released from the jaws of the bat.

Currently there are three babies still suckling from their mothers in the main tunnel, though it is very difficult to see them as they are often hidden under the cover of their mothers membranous appendages.

Separate to the tunnel is the bat hospital which is reserved for permanently injured or young bats. The injuries on the hospitalised bats range from an amputated thumb (the only one used to climb on the netting) to a completely missing foot which, if one hangs upside down, is not an advantage. Bats are unable to fly in the hospital as it is not long enough; this promotes recovery for the individuals wanting to be transferred into the main tunnel. Great enclosure in my opinion and the bats seem thoroughly happy with it too!

More updates to come on the fantastic animals and enclosures at Durrell in the coming weeks; this one, however, will be hard to beat.