What does the diversity of freshwater invertebrates tell us about ecosystem health?

Most of the world’s fresh waters are trapped in ice, underground aquifers and soil moisture. Only about 0.5% of the Earth’s fresh water is present in rivers, lakes and wetlands which cover merely 1% of the Earth’s surface.

Despite this small area, freshwater habitats are extremely rich in biodiversity, harbouring 10% of all described flora and fauna. These include about 1/3 of all vertebrate species, particularly fish, but most aquatic animals are invertebrates such as snails, prawns and aquatic insects (like dragonfly and mayfly nymphs, beetles and bugs).

All the different species of aquatic invertebrates vary in their tolerance to different environments for example to still or flowing water, to different temperatures, and to various pollutants.

In this video we explore how pristine environments, such as forested streams, exhibit the greatest biodiversity, while human impacts such as urbanization, deforestation, dams, and agriculture cause dramatic decreases in the diversity of fauna of rivers, lakes and swamps.