Rabbits and Minotaurs - An Ecological Quandary
Rabbits leave the remains of their digestive tract on little ‘tuffets’ in Bat Park
20th February 2024
Today I've set myself the task of continuing putting up my rabbit-proof fence in the Bat Park area of Wilderness Wood. However, in typical ecological fashion I've discovered a problem whilst trying to exclude Peter, Benjamin and all the other members of the Rabbit family from dining out on our Acid Lowland Grassland. More of that later though (or if you just can't wait please go to “An Ecological Quandary” below).
I had initially intended telling you about what little I know of Rabbit natural history. So here it is:
Rabbit Natural History
You may or may not be aware that rabbits are not native to the British Isles, having been introduced by the Norman's in 12th Century AD as a source of meat. I know what you are thinking “what did the Normans ever do for us?”
“Well they introduced rabbits.”
“Yeah but what did rabbits ever do for us?”
But it wasn't long before many had escaped from their ‘warrens’ and into the wild, where they found plenty to eat - they are pretty happy eating most plants, including an irritating habit of the bark of young trees in winter.
The fact that most of their predators were persecuted by man for the following 800 years (think - fox, stoat, birds of prey) and they breed - well like rabbits - both of which did much to help their spread in the wild.
They are fond of burrowing into hedge banks, although our local rabbit catcher could find no trace of them, or their burrows, at Bat Park.
Jake believes that most of them have their burrows near the Christmas Tree Field, where they cause damage to young trees. The rabbit fence around it has to be constantly checked for signs of them burrowing underneath. The previous owner, Chris Yarrow, even reports seeing at least one individual actually climbing over the fence!
Jake likes to use the open spaces of Bat Park for hunting them, which they like to wander over to quite frequently. Here they sample the grass, which is cropped to within a centimeter or two of the ground.
At Bat Park and almost any other place where rabbits graze, you will find their raisin sized, hard pellets scattered over slightly raised latrine areas. Sort of tuffets, of the Miss Muffet variety. The ones they leave around have actually been through there digestive system twice - yes they eat their own poo!
In the 1950s rabbits were nearly wiped out in Britain when the myxomatosis virus was introduced into the UK. It is thought some 40 million rabbits populate these islands today, although this number increases significantly each spring and summer.
Rabbits at Wilderness Wood
Putting in a rabbit proof fence around Bat Park was always going to be a challenge, if The Christmas Tree Field is anything to go by, but I'm hopeful that if we can bury the bottom of the fence a little and check for activity on a weekly basis then we might at least control their numbers.
One thing I have noticed is how few there are in the field at the back of my house in Battle, not 15 miles from Wilderness Wood. I suspect their natural predators are deterred by Man and domestic dogs. Wilderness Wood attracts both of these in quite large numbers, which may account for why I have yet to see a fox around here in the 10 years I have been volunteering. No foxes, stoats, weasels or large birds of prey, that could well explain our problem, but it's one which we have got to try to manage as best we can.
I attended a Zoom based lecture on rabbits a couple of years ago. The lecturer worked in the Brecklands of Norfolk and believed that the rabbits there played an important part in the control of some of the more aggressive plant species to the benefit of low growing, rosette forming flowers. I've recently noticed that Bat Park has a growing population of Centaury, whilst last year I started seeing the seedlings of several other species, including Oxeye Daisy, Tormentil, Self Heal and Sheep Sorrel. Hopefully these too are resistant to rabbit depredation. So that could well be the case at Bat Park.
For the last 6 years I have been recording the changes in plant species in four permanent quadrats, each measuring 2 metres square. Two of them were originally enclosed by an 18 inch high chicken wire fence to keep the rabbits out, whilst the other two were left open to their depredations - what we call a ‘control’. Not surprisingly the unenclosed control plots suffered the same grazing impact as the rest of the grassland. The experimental plots however did significantly better - with the rabbits being excluded pretty effectively.
The short, rabbit-grazed turf of Bat Park with the four permanent quadrats in the distance.
Last year we finished putting our deer fence extension around Bat Park and removed the tree guards from our hedge saplings. This may have been a tad premature, since rabbits can also browse/graze the bark of young shrubs. Nonetheless, I have high hopes that with both deer and rabbit excluded, we should get grass and wildflower growth - comparable to that until now only found in the rabbit excluded quadrats.
Dung Beetles
Over the last few years I've noticed increasing numbers of 1-2cm holes appearing all around the acid lowland grassland part of Bat Park. These have recently spread to the heathland area too. Each hole has a tail of mined soil adjacent to it, a bit like a long curling squirt from a tube of toothpaste. It is obvious that whoever dug this hole must have ejected this matter too. My initial thought was that they could be mining wasps or even bumble bees, but local bumblebee expert Dave Goulson said they weren't.
One of the mystery holes at Bat Park - this time in the heathland area.
Today I got my answer when I spotted a movement at the mouth of one of the new holes in the heathland. Quick as a flash I grabbed my spade and dug a divot out of the bare soil and discovered 2 modestly sized, black, chunky beetles. Each was about 2 cm in length with 3 horns arranged close to their heads.
Using mobile technology it didn't take long for me to discover they were Minotaur Beetles. The 3 horns (which doubtless gives them their name) confirmed they were both male, which perhaps surprised me, since I assumed they ought to be one of either gender (but in these enlightened times I'm not going to question why two male dung beetles might choose to cohabit).
Male Minotaur Beetle - note the 3 horns on its thorax
It seems that this particular species is rare and protected in Germany, but relatively common on heathlands in the UK, especially where there is lots of rabbit poo. So they came to the right place here in Bat Park.
Now all they have to do is gather up a number of rabbit ‘raisins’, bury them in their beetle hole and find a female to mate with. The rabbit poo is placed next to the developing beetle larva and after a short period of time consuming these delicious delicacies, there will be further dung beetles at Bat Park.
An Ecological Quandary
I am both delighted and concerned by this new development. On the one hand dung beetles will turn the soil over and mix dung into it - great (within reason) for plant growth. They will also provide food for predators further up the food chain, giving us a nice healthy habitat.
On the other hand I am in a quandary. If I exclude the rabbits, then all of Mother Nature's excellent work providing for dung beetles and their predators will be undone. On the other hand, if I allow the rabbits free access they will graze my hallowed Bat Park turf to a bowling green.
So there you have it. An ecological quandary.
Perhaps I could insert a rabbit flap in the fence and have open days? Alternatively I need to grab a shovel and go poo hunting. Perhaps all those dog turds I was raging about a few weeks earlier will be beneficial after all?