Cover Image
close this bookBiodiversity in the Western Ghats: An Information Kit (IIRR, 1994, 224 p.)
close this folder1. Front matter
View the document1.1 About this information kit
View the document1.2 Workshop participants
View the document1.3 Introduction to biodiversity
View the document1.4 User survey
View the document1.5 Biodiversity: A synthesis
close this folder2. Threats
View the document2.1 Biodiversity of the Western Ghats
View the document2.2 Threats to biodiversity
View the document2.3 Urbanization and biodiversity
View the document2.4 Population and biodiversity in the Western Ghats
View the document2.5 Pollution in Goa's rivers and estuaries
View the document2.6 Atmospheric pollution and biodiversity
View the document2.7 Managing solid waste
View the document2.8 Traffic in wildlife products
View the document2.9 Effect of tobacco growing on biodiversity
View the document2.10 For those vanishing species
close this folder3. Marine
View the document3.1 Biodiversity of the Arabian Sea
View the document3.2 Seaweeds
View the document3.3 O verexploitation of of marine living resources
View the document3.4 Small-sector coastal fisheries along the Kerala coast
View the document3.5 Coral reefs
View the document3.6 Crabs
View the document3.7 Estuarine shellfish
View the document3.8 Fish
View the document3.9 Coastal ecosystems
View the document3.10 Coastal sand dune vegetation
View the document3.11 Fish breeding and habitat
close this folder4. Fresh- and brackishwater
View the document4.1 Estuarine ecosystems
View the document4.2 Mangroves
View the document4.3 Mangrove communities
View the document4.4 Wetlands
View the document4.5 Freshwater wetlands: Carambolim Lake
View the document4.6 Freshwater algae
close this folder5. Agriculture
View the document5.1 Rice diversity and conservation in the Konkan
View the document5.2 Conservation of traditional vegetables in the backyard
View the document5.3 Genetic diversity in mango and cashew
View the document5.4 Floriculture and arboriculture
View the document5.5 Enriched biodiversity by plant introductions
View the document5.6 Impact of introduced plants
View the document5.7 Effects of pesticides on biodiversity
View the document5.8 Khazan (saline) lands
close this folder6. Plants, fungi and bacteria
View the document6.1 Plant associations of the central Western Ghats
View the document6.2 Rare and endangered flowering plants
View the document6.3 Medicinal resources from the forest and sea
View the document6.4 Poisonous plants
View the document6.5 Fungi: Biodiversity, ecology and use
View the document6.6 Conserving fungi
View the document6.7 Edible mushrooms
View the document6.8 Microbial biodiversity of salt pans
close this folder7. Invertebrates
View the document7.1 Butterflies
View the document7.2 Honeybees to conserve biodiversity
View the document7.3 Mulberry silkworms
View the document7.4 Spiders
View the document7.5 Conserving natural enemies of mosquitoes
View the document7.6 Vermicomposting
close this folder8. Reptiles, birds and mammals
View the document8.1 Snakes
View the document8.2 Crocodiles
View the document8.3 Birds
View the document8.4 Mammals
View the document8.5 Animal diversity in prehistoric rock-art
close this folder9. Appreciating and conserving biodiversity
View the document9.1 Biodiversity and the media
View the document9.2 Role of non-government organizations in conservation
View the document9.3 Watershed management
View the document9.4 Energy conservation and alternatives
View the document9.5 Nature trails
View the document9.6 Sacred groves
View the document9.7 Rehabilitation of iron ore mine wasteland in Goa
View the document9.8 Reforestation to restore mining areas
View the document9.9 Mining: Social and environmental impacts
View the document9.10 Resource utilization in Uttar Kannada district
View the document9.11 Biodiversity of Dudhsagar valley
close this folder10. Reference
View the document10.1 National parks and sanctuaries in the Western Ghats
View the document10.2 Glossary
View the document10.3 NGOs in the Western Ghats states

7.4 Spiders

Colourful web-weavers-and scary to some-spiders are little known or appreciated creatures. Like insects, they are invertebrates (they have no backbone). But they are not insects; rather, they are arachnids, related to scorpions, ticks, mites and king crabs.

There are 30,000 species of spiders distributed over 60 families worldwide. In India there are about 43 families of spiders.

Spiders inhabit a wide range of ecosystems because they can tide over periods of food shortage and take advantage of periods of abundance. In the Western Ghats, they are found in a variety of microhabitats-tree bark and trunks, rock crevices, under leaves and stones, below bushes, on walls of houses, in tunnels and burrows, and near water.

Spiders as big-control agents

Spiders are important biological control agents of animal and plant pests. The giant crab spider (Heteropoda venatoria) prefers cockroaches and other insects. Wolf spiders relish brown planthoppers-a pest dreaded by rice farmers.

Threats to spiders

· Many pesticides kill beneficial spiders as well as insect pests. Indiscriminate use can lead to increases in pest numbers because spiders and other predators are wiped out. Some species of spider may be endangered because of such use.

· As with all species, the destruction of habitat through deforestation and other changes may reduce the number of spiders.

· Many people are afraid of spiders. Instead of being seen as friends and vital parts of the ecosystem, spiders are often indiscriminately killed.

Conservation approaches

· Raise the general awareness of the important role spiders play in the Western Ghat ecosystem.
· Study spiders' role as big-control agents in agriculture.
· Explore various uses of silk-for instance, for fishing nets. The use of webs in bulletproof vests is being studied.
· Do not destroy forest patches-the home of many spiders.
· Study the role of spiders in maintaining the stability of an ecosystem and their relation to other forms of life.

Arachnids vs insects



8 legs

6 legs

2 body

3 body


parts: head,





6-8 simple eyes

Compound eyes

No antennae


Young resemble adults

Young differ from adults

Mature by moulting

Mature in stages

Arachnids vs insects

Uses of spider silk

· Tribal people in Australia and Papua New Guinea use the web of Nephila sp. to make fishing nets.

· Some tribal people in Maharashtra mix spider silk with jaggery to make native medicine to control fever.

· Spider silk is used as a healing agent in Unani medicine.

Some common spiders of the Western Ghats



Look for them...

Mygalomorp spiders


On the ground, in tree hollows and burrows

Argiope sp.


Tree trunks, bushes

Gasteracantha sp.


Low bushes and in trees

Herennia spider


Walls of houses in forest, trunk of tree

Giant Wood spider


Trees and bushes in thick forests

Social Web spider


Trees and bushes

Two-tail spider


Tree trunk and walls of houses

Heteropoda spider


Cracks and crevices, in houses

Wolf spiders


Base of tree trunks, under stones, in shrubs, on grasses, in tunnels and burrows

Lynx spider


Plant leaves, grass, shrubs

Dancing spider


Tree hollows, corners of houses

Jumping spiders


Tree, bushes, inside houses

Tetragnatha spiders


Inside wells, grasses near water

Crab spiders


On flowers

Spider facts

· All spiders are carnivorous and feed only on living prey.

· Spider silk is a kind of protein, used not only for trapping prey but in egg cases, nest lining and as a food source.

· All spiders are poisonous to their prey. Only a few are highly venomous and can kill a human being.

· Spiders may live from several months to ten years in their natural habitats.

· All spiders are solitary except for the group known as "social web spiders", which live in colonies.

· Certain species of sunbirds use the nests of social web spiders for their nests.

Spider myths

The term Arachnidae is derived from the Greek Arachne, meaning spider. The legendary Arachne wove exquisite tapestries. She was invited to a weaving competition with the Goddess Athene, whom she defeated. The enraged Athene tore the tapestry and Arachne killed herself. It is said that Athene changed Arachne to a spider so that she could continue spinning beautiful tapestries!

Spiders are also mentioned in Hindu mythology as worshippers and protectors of Lord Shiva.

The jumping spider anchors itself to the ground with a silk thread before it jumps on its prey.

The jumping spider

By R. Bhanumati