Attack of the wild boars, and our response

Written by Logan Sander, December 21, 2016 (edited by Laura)

This past week saw several new developments in our nursery. While the three of us were traveling we received disturbing news from Somaratne and Dr. Singhakumara: wild boars (ura) had ransacked our nursery, eating our banana, coconut and taro seedlings! The true extent of the damage wasn’t as bad as we had feared, and upon our return we were able to salvage several of the plants. Still, this meant we would need to take measures to counteract what had been our chief anxiety about the nursery to this point: wild animals. Coincidentally, the evening we received this news Laura and I had just visited the National Museum in Colombo and its fine exhibit on traditional agriculture and livelihoods. Aside from the obvious solution of fencing in our nursery, we saw a working model of a non-physical deterrent: a “water-ghost.”

The exhibit said that farmers had often used these “water-ghosts” whenever pest animals were eating or destroying crops. To operate, water pours into a piece of bamboo “pipe” until the bamboo’s chambers are filled, at which point its center of gravity shifts and the bamboo swivels downward, dumping its water onto the ground. With this, the center of gravity suddenly shifts again and the bamboo pipe swivels back, rapidly striking a rock. A half-coconut shell is loosely attached to the striking end of the bamboo, creating a high-pitched percussive effect on impact. This sound is supposed to startle and unsettle approaching animals. It’s unclear to me if this would be effective on wild boar, but in addition to a fence it seemed like a fine opportunity to give a water-ghost a try. It would certainly be fun to build and would give us another chance to showcase traditional appropriate technology in our homegarden.      
 

Piping water from our water-tank’s overflow to our nursery

The water-ghost took all of an hour to construct, with Tillekaratne and Somaratne’s help. We piped water from our water tank’s overflow (with our newly- made bamboo pipes) down to our nursery and into the water ghost. Success! Every 4.5 seconds the gentle sounds of birds and insects in our little valley are punctuated with a low-pitched popping sound – something like a whiffleball being struck by a hollow bat - audible from a distance (including the field station) but not at all unpleasant (so far...). Hopefully we read the right placard at the National Museum and this isn’t actually a wild elephant call! 

We chose to divert the stream of water flowing from the water-ghost into a small pond we constructed. We have been having trouble with our water system when we needed to water our plants; the rapid shifts in pressure when we open and close the valve on our water line tends to separate the plastic pipe somewhere up- valley. This can be incredibly inconvenient, as the water pipe is occasionally strung 20 feet above the river! The pond allows us to dip our watering can and avoid the use of the spigot and this dilemma altogether. We conveniently found a deep, pure clay deposit right at the edge of the river where we bathe. We used a few shovel- scoops of the clay to line a hole we dug and built up with rocks and then connected our new piping to fill the pond. So far, the seal appears to be nearly perfect – even with inflow turned off we don’t lose water out of the pond! 

Applying river clay to create a small pond

 

Nepenthes (pitcher-plant) stem used to lash sticks together

Our “water-ghost” and pond

Our other animal deterrent project was to build a fence. This was fairly straightforward: cut and bury posts, nail stringers between the posts and unroll and hang metal fencing. Most of the wood cut for the fence was from small, short-lived early-successional trees. We enclosed one section of the garden with 5’ chain-link fencing; another with 3’ chicken wire; and the final section left unfenced. The plants we know boars and other animals (mostly goona, or wild deer) like to eat go in the tall, chain-link fence. The other plants that show evidence of browsing (apparently from smaller animals) go in the shorter fence. Germinating seeds and unpalatable plants are so far unfenced. To us this seems like an economical and reliable method of making sure our nursery receives minimal damage from the local wildlife. Of course, an elephant would see our fencing as a feeding trough, but elephants are relatively rare in this valley. Locals report that there are two elephants that occasionally come here, but at intervals of a few years... We’ll keep our fingers crossed that we can have the homegarden planted out and established by the time they make the rounds again. Five days later and our nursery is much more secure (actually, a little prison-like), and just a little bit noisier...

Bringing chain-link fencing from the road to the field station

Building the fence. Posts were from fast-growing secondary species cut near the nursery

Wildlife exclosure or plant prison?

 

The completed “tall” fence

Working on the “low” fence

  P.S. It has been brought to our attention by a local researcher that our pond closely resembles a wild boar wallow. Expect updates as to our countermeasures’ efficacy...