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Water Quality of A Stream Using the Biotic Index





Grade Levels

3rd-5th

Subjects

Science
Living Environment

Keywords

trout in the classroom, water quality, macroinvertebrates

Forest Locations

The stream near the science center will be used as long as the science center.



Download Trail Map




Materials

plastic ice cube trays, plastic spoons, eye droppers, hand lenses, petri dishes, white dish pans, kick nets, macroinvertebrate sorting chart and cards, data collection forms,  Critter game cards (laminated), waders with boots, permanent marker, clipboards, pens

Schedule

Pre-Forest Activity

Teacher will label with permanent marker (mayfly, stonefly, caddisflies), worm, midge, leech,  damsel fly, etc) the parts of the ice cube tray.

Students will learn about the definition of a macroinvertebrate and be introduced to a variety of macroinvertebrates that they may encounter on their stream study.  

They will also be instructed on the proper procedure to do a stream sample and be introduced to the different equipment that they will be using during their stream sampling. 

They will play at "Critter game" which shows the various macroinvertebrates that they will find and understand what aquatic bugs make a healthy stream versus an unhealthy stream. 

The students  have been collecting data on their various trout ( at varying life cycles) at the end of this trout in the classroom activity, the trout will be released .The purpose of this lesson is to determine if the trout can be released in the river at Black Rock based on the water quality. 

Forest Activity

Field Trip Lesson:  Prior to getting to Black Rock, the students will be broken up into groups of 4. The teams will need to partner up with one other person to do the macroinvertebrate collection. The students will be given a section of the stream (2 meter length of the stream). Each pair of students will use flags to mark off their section of the stream.  The  students will have ten minutes to collect macroinvertebrates with their kick nets and give their materials to the students not collecting ( by dumping into bus tubs). After ten minutes, the two teams will switch positions. Once both teams have finished collecting macroinvertebrates, the whole team will process the sample. They will use their charts and cards to help them sort the organisms into sections of the ice cube trays  ( with water).  

Set up a transect.  

Collection procedure:  

One person should stand down stream holding the kick net firmly on the bottom. The other person should be standing a couple feet in front of them. They should be kicking rocks and sediment in front of the net, to disturb the stream bottom ( where all the macroinvertebrates on the dead leaves, etc). After they have done a small section, they will dump their contents into the white sorting tray. They will move downstream to do a new section of their transect.  Each member of the team will get a chance to participate in the macroinvertebrate sample gathering. After completion of their macroinvertebrate sampling they will carefully remove any debris ( sticks, leaves,etc) from their white container and begin to remove organisms and place into their ice cube tray with others that are identical. They will begin to identify the macroinvertebrates and match to the corresponding label on the tray.  

Students will record how many macroinvertebrates of each type they have by marking it on their data sheet. When they have completed this task, the organisms will be carefully transported back to their transect section. This data will be taken back to the classroom where all data will be processed. Each group will share out their results so we add the total number of organisms to determine the quality of the stream water. 

Data sheet for collection: https://tnf9u43u8s42cg8l3sksfn28-wpengine.netdna-ssl.com/wp-content/uploads/4_LPNDataSheets_2012.pdf 

This data sheet includes an easy tally marker spot for students, along with pictures to ID the  macroinvertebrates. 

 

Evaluation of Water Quality from Biotic Index 

Biotic Index 

Water Quality 

Degree of Organic Pollution 

Less than or equal to 3.75 

Excellent 

Organic pollution unlikely 

3.76 to 5.0 

Good 

Some organic pollution 

5.1 to 6.5 

Fair 

Substantial pollution likely 

6.6 to10.0 

Poor 

Severe organic pollution likely 
 
 

 

 

 

 

 

Post-Forest Activity

The students will bring back their data sheets and as a class we will add up/ average the total number of each macroinvertebrates.

In classroom project the biotic index ( to add up everyones numbers). Use the following website to get the answer to

https://leafpacknetwork.org/biotic-index/ 

 

Using their tally sheets, we will get the biotic index.  

Assessments





Learning Standards

3-LS3-2. Use evidence to support the explanation that traits can be influenced by the environment. [Clarification Statement: Examples of the environment affecting a trait could include normally tall plants grown with insufficient water are stunted; and, a pet dog that is given too much food and little exercise may become overweight.]

3-LS4-2. Use evidence to construct an explanation for how the variations in characteristics among individuals of the same species may provide advantages in surviving, finding mates, and reproducing. [Clarification Statement: Examples of cause and effect relationships could include plants that have larger thorns than other plants may be less likely to be eaten by predato

Curriculum

Pre- Trip: Students will learn about the definition of a macroinvertebrate and be introduced to a variety of macroinvertebrates that they may encounter on their stream study.  

They will also be instructed on the proper procedure to do a stream sample and be introduced to the different equipment that they will be using during their stream sampling. 

They will play at "Critter game" which shows the various macroinvertebrates that they will find and understand what aquatic bugs make a healthy stream versus an unhealthy stream. 

The students  have been collecting data on their various trout ( at varying life cycles) at the end of this trout in the classroom activity, the trout will be released .The purpose of this lesson is to determine if the trout can be released in the river at Black Rock based on the water quality. 

Objectives

Students will learn how to measure the quality of the water with key indicators.

Background

Students will be calculating the EPT ( health of the stream) back in the classroom. EPT Richness Estimate: An estimate of the number of different kinds of mayfly (Ephemeroptera), stonefly (Plecoptera), and caddisfly (Trichoptera) The EPT’s tend to be particularly sensitive to pollution.  

Live samples are assessed for the presence of four orders of relatively pollution sensitive stream organisms, and the absence (or sparseness) of worms, which tend to be very pollution tolerant. The four pollution sensitive orders are mayflies, stoneflies, caddisflies and beetles. There is a caveat that netspinner caddisflies (a relatively pollution tolerant family) do not dominate the sample, and dobsonflies or fishflies may be substituted for beetles. The presence of the four orders, with an absence or scarcity of worms, indicates a non-impacted stream. This method is not for quantitative analysis.  

Safety Concerns

Students should be sprayed with bug spray before going on the trip. Waders need to be used in the stream and students will have to be careful on slippery rocks.

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