The sublime spectacle of Balinese ricefields and terraces usually encouragesreflections of a tranquil and meditative nature, but amongst thoseluscious, viridian-green rice stalks, and beneath the still waters of theflooded padi field ragesa ferocious battlefor survival. Monstrouspredators gorge themselves onhapless prey, while voracious herbivores feast on the maturing rice plantswith the rapacity of runaway lawn mowers. No Garden of Eden this !
Insects are a considerable menace to the success of the rice crop and they come in a variety of forms and dietary preferences. There are stem borers, leaf- folders, leafhoppers, planthoppers and any number of bugs which simply enjoy eating rice as much as the Balinese. The brown planthopper (Nilaparvartalugens) is an especially noisome beast which not only damages the rice plant by sucking sap from the vascular system of the leaves, but also, by this means, introduces viral infections directly to the plant. The seriousness of the damage inflicted by brown planthoppers is exacerbated by the fact that they are able to reproduce themselves in vast numbers and with great alacrity. Females can lay between 100-300 eggs in a three week laying period, with only four weeks between successive generations, while males are ready to mate just one day after hatching and go on to survive for almost a month subsequently. Whatis more, theeggs of the brownplanthopper are laid deep inthe leaf sheath of the rice plantwhich means that pesticides areunlikely to reach them.Actually pesticides are part oftheproblem, rather than the solution, in that they do not discriminatebetween ‘good’ bugs and ‘baddies’ so that their widespread use in recent years has decimated the natural predators of planthoppers. In the past, when rice was grown under more ‘natural’ conditions, planthoppers were subject to the attentions of over one hundred different kinds of predators, parasites and diseases, which kept their numbers under control.
Butplanthoppers don’t have it all their own way, being one step down in the food chain to spiders. Spiders are the most aggressive predators on planthoppers and other small creatures which afflict the pseudannulata) is particularly rapacious and can easily be recognised from the fork-shapedmarking on its back. These Arachnids do not spin webs but lurk instead at the base of rice parts ever ready to jump upon and devour their unsuspecting prey. Spiderlings feed upon planthopper and leafhopper nymphs, while adult wolf spiders indicate a preference for stem borer moths. Each individual wolf spider can dispatch between five to 15 victims a day and in this respect, they are an extremely effective natural agent of pest control.
Birds can also play a useful role in controlling pestilence in the rice fields—cattle egrets (Bulbulcus ibis) and the javan pond heron (Ardeolaspeciosa) are two easily spotted species which commonly occur in Balinese rice fields. Egrets feed on grasshoppers, crickets and spiders, while the javan pond heron prefers dragonflies and water beetle larvae, or spiders and molecrickets. Molecrickets (Gryllotalpa spp.) are a particular nuisance because they live among the roots of the rice plant, feeding on the lower stem and loosening the surrounding soil, causing the plant to wilt.
Frogs find rice fields much to their liking and a variety of species play their part in containing rice pests by dining on grasshoppers, crickets, beetles, bugs, and butterfly and moth larvae.
Ducks enjoy a diet of freshwater snails and Balinese farmers are mindful of this, escorting their ducks each day to their rice fields and allowing them to get on with the job. To prevent the ducks from straying too far in the absence of the farmer, a stick with a small white flag topped by a bunch of white feathers is planted in the mud. Balinese ducks are ‘flxated‘ by this marker and will follow where so ever it leads them. At dusk, they dutifully gather round the base of the flag, awaiting the signal to march home again. All that the duck·keeper has to do is simply to uproot the staff and walk back through the rice fields to his family compound, assured that his flock of ducks will follow closely at his heels.