Freshwater aquaculture

Practical 4 - Aquatic insects

Introduction

• Insects are the most diverse and successful group of animals
• Nearly 80% of the world fauna are insects
• Quite a large number of insects spend at least part of their life in water
• 11 orders inhabit water – out of these only beetles and bugs spend their whole life in water
• They are dependent on atmospheric air for respiration
• Hence, more prevalent in shallow waters
• They are generally desirable on fish ponds since they are important part of the aquatic food web
• However, in nursery ponds they are undesirable, since they feed on spawn and fry.
• They also compete with spawn for food and space.

Major aquatic orders

• Hemiptera
• Coleoptera
• Odonata

Minor orders

• Ephemeroptera
• Trichoptera
• Lepidoptera
• Diptera