Biological Properties

Biological Properties

• Biological attributes of a waterway can be important indicators of water quality. Biological attributes refer to the number and types of organisms that inhabit a waterway. The poorer the quality of water, the fewer the number and types of organisms that can live in it.

Great candidates for biological monitoring…

Benthic Macroinvertebrates

Heptageniidae sp. (Mayfly larva)

Hydropsyche sp. (Caddisfly larva)

Perlodidae sp. (Stonefly larva)

(bottom-dwelling) (animals w/o backbones visible to naked eye)

Macroinvertebrates as Indicators

• Limited migration patterns–good indicators of localized conditions and site-specific impacts

Easy to sample and identify

• Broad range of habitat requirements and sensitivities to pollution

The Tolerance Index0 - 10

most pollution sensitivee.g. Stoneflies

0 10

most pollution tolerant e.g. Midges & Leeches

require high DO, clear water, rocky cobble substrate

contain hemoglobin, tolerate lower DO, prefer soft substrate, less sensitive to toxins

Stonefly Water Penny Beetle Mayfly Dobsonfly

Alderfly Mussel Snipe Fly Riffle Beetle

Macroinvertebrates as Indicators

Pollution Sensitive (“Clean Water”) Benthos

Macroinvertebrates as Indicators

Blackfly Caddisfly Isopod Cranefly

Damselfly Dragonfly Crayfish Amphipod

Somewhat Pollution Tolerant Benthos

Macroinvertebrates as Indicators

Pouch Snail Midgefly Worm Leech

Pollution Tolerant (“Polluted Water”) Benthos