Comprehensive Grammar School
Methuen, Massachusetts

“Does fresh water all over the world have the same organisms” is the question that Mrs. Turmel’s 4^th grade class at the Comprehensive Grammar School in Methuen was ready to investigate.  We talked about this question in class, discussed what we knew about ponds, and came to the hypothesis that some of the macro invertebrates we expected to find would also be found in some other parts of the country.  We also believed that due to an area’s climate, there might be some macro invertebrates that would only live in certain parts of the country or world.

Sample Collection Day: Hills Pond in Methuen

On Sunday, October 29^th, Mrs. Turmel went to Hills Pond in Methuen to collect water samples for our class.  The day was brisk and windy and the temperature at the pond was 42 degrees Fahrenheit.  She took many pictures of the plants in and around the pond such as lily pads, reeds, cattails, bittersweet, and milkweed.  On the day she went to the pond, she couldn’t see any signs of life, except for one duck swimming on the pond.

Analyzing the Water

On Monday, October 30^th our class analyzed water samples and were surprised when we found so many living creatures!  We were afraid that because the day our teacher collected the water was so cold; all the macro invertebrates had either died or buried themselves beneath the muck of the pond.  Mrs. Turmel had a huge bucket of pond water and scooped out 6 containers full of the water and the pond muck she had collected for each of our 6 groups.  Pretty soon, as each group looked at the water, we could hear everyone excitedly talking about the live creatures we could see living there.  That day, we collected several samples and put them on slides under the microscope so that we could use the chart to identify them.  On Tuesday, October 31^st, we looked at other samples of the water and found more creatures.  One member of our class had the ingenious idea of using the tip of his pencil (the eraser part) to grab a creature, since we didn’t have a small enough net.  The eraser worked great.

Our Findings
After looking at each macro invertebrate we found under a microscope, we all agreed that we found every macro invertebrate listed on the Bucket Buddies chart.  We found the following macro invertebrates living in Hills Pond:

Amphipods, Caddish fly larva, Damselfly nymphs, Water fleas, Dragonfly

Nymphs, Mayfly nymphs, Midge larva,  Mosquito larva, Snail, and Bristle worm. 

In addition, we also found a clear jelly like clump (1-2 cm) that had some small brown dots in the center.  We haven’t yet been able to identify it, but we think it might be a sac holding eggs of one of the macro invertebrates we found.  On the whole, we found a lot of Damselfly nymphs and most of the creatures we found were in the nymph category.

Our Conclusions

We think that Hills Pond must not be polluted if so many creatures are able to survive there.  We’re interested comparing our findings to other schools’ results and finding out if our hypothesis is correct.