IN THE WILD: Making sense of spiders By Rahul Alvares / cna at sancharnet.in
One of the creatures I studied about when I took a year off from School was spiders. I worked under Dr. Vijayalakshmi in Madras, who is an expert in rearing Giant Crab spiders - a species she uses especially to control cockroaches. My real interest even at that time was reptiles, but I was keen on learning about these animals as well. Yes animals! You read right. Though people often relate the word 'animal' to mammals, the actual definition of 'animal' includes sponges, jelly fishes, worms, fishes, birds, frogs, snakes and mammals! The Giant crab spider is slightly smaller than an adult cockroach, does not build webs, but is a skilled hunter. The spider's method of preying is to chase the cockroach, jump on its back and then kill it with its poisonous bite. It doesn't posses teeth so it only sucks the body fluids of its prey. This spider is common in Goa. Relax! Its bite is as painful and harmless as an ant's. Each one of these spiders can produce hundreds of young and Dr. Vijaylakshmi breeds thousands, which she distributes to people who prefer these bio control agents, instead of using harmful chemicals to kill pests. All her work and research was conducted in one small garage room, which was full of shelves on which stood hundreds of little plastic bottles each housing a single spider. Excepting for one species all spiders are cannibalistic and live alone, thus from birth each spider has to be kept separate. Dr. Vijayalakshmi also had a good number of books, which I devoured in no time at all. Reading about the life of a spider can be as interesting as a novel. In all my experience with wildlife I have found that the most remarkable in terms of behaviour and diversity are the little animals like spiders, Antlions, insects and scorpions. Though I haven't read much about other little animals, I must say that the most versatile, diverse and interesting creature I have known is the spider. People often mistake spiders to be insects. Insects have six legs, grow wings and posses compound eyes. Whereas spiders are arachnids having eight legs, simple eyes (eight in number!) and grow no wings at any stage of their life. It is also interesting to know that all spiders don't build webs. Many species like the Jumping spiders posses sharp eyesight allowing them to stalk and hunt their prey. Some like the Ogre- Faced spider spin a web like a net which they throw on insects passing around. The Bolas spider spins a long thread at the end of which is a sticky drop, which it waves about in the air lassoing insects as they fly by. Some species feed only on other spiders and are called Pirate spiders! And some are so small that they go unnoticed living in the webs of much bigger spiders' feeding only on the leftovers kills of their hosts. They have an array of camouflage methods as well. Some look like a bird dropping. Many mimic ants, which are rejected by birds due to their expulsion of formic acid when attacked. A few species can change colour better than chameleons, and hide in flowers. A tricky part for them is romance. The male is often very small, and therefore runs the risk of being eaten up before he gets to mate with the female. The male has to trick the female before he can mate with her. Before setting out in search of a female, a male spider secretes his sperm into a silky packet and holds it in his mouth. Mating is a simple act of applying this packet to the female's genital organs and then making a quick getta way. Some males will hunt an insect, then roll it with silk into an attractive bundle and offer it to the female as a present to distract her while mating. This may well be taken back after mating and offered to another eligible female instead. Very often the male will offer a silk wrapped gift which is actually empty inside! While the female is preoccupied opening it, the male mates and flees. Males of species with poor vision drum a rhythmic beat on the web strands of the female, to announce that they are sexual objects and not prey. Some males may go to the extent of loosely binding their mates with silk to render them powerless, while they copulate. A few species of males are smaller than the female's prey species, and practically go unnoticed during mating! Most people are scared of spiders. Actually only three or four like the Recluse spider or the Black Widow (the female kills the male after mating) out of the 30,000 species in the world are really dangerous. India harbours no poisonous species. Most people are also ignorant of the indispensable role that spiders play in the proper functioning of the ecosystem. Spiders can multiply quickly when pest population increases, and tide over unfavourable conditions by fasting for months at a time, making them perfect pest control agents. And like all Mother Nature's animals they have no side effects. Spiders have other amazing uses as well. Spider web has been used on wounds for centuries because of its clotting properties. Spider silk is stronger than steel of the same diameter and is used in making gunsights. They make interesting pets. Tarantulas are known to live for 12 years. I spent hardly nine days with spiders in Madras. So I know that the information I gained is only enough to graze the tip of the iceberg in the spider kingdom. If this article has interested you then you should know that there are a million other fascinating details about spiders, which picked up as a 'spider watching' hobby could keep oneself occupied for a lifetime. And the best part is that you don't have to go to the jungles and forests to do 'spider watching'. You can start right in your own house. [The writer is a young wildlife enthusiast from Goa, India] ########################################################################## # Send submissions for Goanet to [EMAIL PROTECTED] # # PLEASE remember to stay on-topic (related to Goa), and avoid top-posts # # More details on Goanet at http://joingoanet.shorturl.com/ # # Please keep your discussion/tone polite, to reflect respect to others # ##########################################################################
