Audubon Naturalist Society GreenKids Stream Study

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Audubon Naturalist Society
GreenKidsStream Study
Prepared for teachers and 4th grade students
October 2008
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Water Quality Check-Up

• We will study a local stream to check on its
  health.
• To do this, we will look at habitat in and around
  the stream, and search for creatures (aquatic
  organisms) living in the stream.

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What are aquatic organisms?
Aquatic organisms are animals that live in the
stream. They help tell us about the water quality
of a stream. The ones we will search for are
called.are you ready? Benthic
Macroinvertebrates!
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Benthic Macroinvertebrates?
BENTHIC the habitat at the bottom of the stream
including, rocks, sediments, plants, fallen
leaves, debris MACRO larger than ½ millimeter
about the size of the dot you make with a pencil
on a piece of paper (.) and larger. You need to
look carefully! INVERTEBRATES animals without
backbones. We will search for animals without
backbones living at the bottom of the stream that
are ½ millimeter or larger.
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Benthic Macroinvertebrates Benthos
Scientists and volunteers who study streams often
refer to benthic macroinvertebrates as
benthos.
Non-scientists may use other terms like
creatures, critters, bugs, etc.
Well stick to benthos or benthic
macroinvertebrates.
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Why do we look for benthic macroinvertebrates?

• There are a lot of different kinds of benthos.
  They are an important part of the food chain in a
  stream.
• Some can only live in very clean water. If we
  find benthos that can only survive in very clean
  water, we know that the water quality in the
  stream is good or excellent.
• Others can survive in polluted water and poor
  habitat conditions. If we only find benthos that
  can survive in these conditions, we know that the
  water quality in the stream is fair or poor.

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Can you think of examples of benthic
macroinvertebrates?
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Examples of Benthic Macroinvertebrates

• Stoneflies
• Immature form of an aquatic insect, nymph

Stoneflies are usually only found in cleaner
waters. If we find stoneflies, the water quality
and habitat conditions in the stream are good.
Adult
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Examples of Benthic Macroinvertebrates

• Mayflies
• Immature form of an aquatic insect, nymph

Mayflies may be tolerant of pollution. If we find
them, this generally tells us that the water
quality and habitat conditions in the stream are
good.
Adult
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Examples of Benthic Macroinvertebrates

• Crayfish
• Crustaceans

Crayfish are usually found in fairly clean
streams. If we find them, this tells us that the
water quality and habitat conditions in the
stream are good. This is a photo of a rusty
crayfish which is not native to Maryland and is
considered an invasive species in Maryland
streams.
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Examples of Benthic Macroinvertebrates

• Dragonflies
• Immature form of an aquatic insect, nymph

Dragonflies can live in moderately polluted
streams. If we find them, the water quality and
habitat conditions in the stream are fair to good
depending on what other benthos we find.
Adult
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Examples of Benthic Macroinvertebrates

• Blackflies
• Immature form of an aquatic insect, nymph

Blackflies can live in moderately polluted
streams. If we find mostly blackfly larvae and
few other benthos, the water quality and habitat
conditions in the stream are fair to poor.
Adult
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Examples of Benthic Macroinvertebrates

• Worms
• Aquatic worms

Aquatic worms tolerate polluted streams. If we
find many worms and few other benthos, the water
quality and habitat conditions in the stream are
very poor.
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What we wear and use to look for benthos
Dipnets
Rubber Boots
Some students will be in the stream catching
benthos.
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What we use to identify and study benthos
Ice trays and plastic bins
Microscopes
Some students will be on the land identifying
benthos.
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Procedures and Expectations
Each student will spend 30 minutes in the stream
and 30 minutes studying the habitat around the
stream. Its important to be prepared to be
around the water
Here are a few reminders of how we can ensure
that we learn about the creek and have fun

• Only go in the water if you are wearing
  waterproof boots. We will bring some extra boots.
• Splashing or running in the water disturbs the
  wildlife. Please walk and be careful while in the
  stream.
• Remember that the nets are for collecting benthic
  invertebrates and should not be swung around.

• Dress for the weather.
• Bring waterproof boots (rain or snow boots will
  work) if you have them.
• Bring a change of pants and socks in case your
  clothes get wet.

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Poison Ivy
Stay away from me! I grow along the trail and up
the trees. Wearing long pants is recommended.