stream organisms require access to food refuge from predators tolerable temperatures

Biological AssessmentDeveloped by Ken Cooke

Kentucky Division of WaterWatershed Watch Program Coordinator

Modified by Mike KempProfessor of Environmental Engineering Technology

Murray State University

Stream organisms require– access to food– refuge from predators– tolerable temperatures– sufficient oxygen– tolerable chemical

conditions

A degraded habitat may not support some organisms.

Benthic Macroinvertebrates• Benthic – bottom of the stream; macro – visible with

the naked eye; invertebrate – no backbone• Ubiquitous and easy to collect• Relatively sedentary• Vary in sensitivity to habitat alteration and pollution

Good Mid Range Poor

A diverse community representing a range of tolerances

A less diverse community dominated by tolerant species

True or False. The presence of pollution tolerant species such as leeches is an indication of poor water quality.

True or False. The presence of pollution tolerant species such as leeches is an indication of poor water quality.

False

Equipment to Bring• Boots, waders, or shoes that can get wet• D-frame or 10-inch aquarium net• Light-colored plastic pan• Field guides, key, and illustrations for identification• Magnifying glass• Biological monitoring assessment datasheet

Selecting the SiteChoose one or more riffles in your stream reach.

Sampling Protocol – traveling kick

1/2 meter line

• Set net in riffle.• Kick and stir 1/2 meters above

net.• Rinse net in pan containing a

small amount of water.• Repeat at five different locations

in riffle to produce one composite sample.

• Inspect and remove large debris• Identify organisms and calculate

score.• Carefully rinse net and pan

before sampling another stream.

Sampling Protocol – low gradient• Estimate habitat present.• “Jab” net in representative

habitat.• Rinse net in pan containing a

small amount of water.• Repeat at ten different locations

in the reach to produce one composite sample.

• Inspect and remove large debris.• Identify organisms and calculate

score.• Carefully rinse net and pan

before sampling another stream.

For each site, how many kick-net samples should be taken?

What should you do if your reach does not have any riffles?

For each site, how many kick-net samples should be taken?

What should you do if your reach does not have any riffles?

Five. These can be combined to form one composite sample.

For each site, how many kick-net samples should be taken?

What should you do if your reach does not have any riffles?

Five. These can be combined to form one composite sample.

Look for other habitats that might support macroinvertebrates. Use the low gradient sampling protocol if necessary.

Identify the following macroinvertebrates:

A

Images from http://www.cals.ncsu.edu/course/ent525/water/aquatic/index.htm

B C

DB. Newton 2003

E F

Identify the following macroinvertebrates:

A B C

DB. Newton 2003

E F

caddisfly larva crane fly larva water penny

mayfly larva scud (isopod) damselfly larvae

Images from http://www.cals.ncsu.edu/course/ent525/water/aquatic/index.htm

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X

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X

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