Hydrology (HYDRO26) Lab Macroinvertebrate Survey

Guest bloggers: Anika Knowles, Cheyenne Wentz, Ellie White and Leo Casalini

The HYDRO ’26 Macroinvertebrate team.

The Objective

The team gathered before starting the survey at Site 1.

Students enrolled in this year’s Hydrology course took a trip down to Apple Creek, a local tributary of the larger Killbuck Creek, to aid in the completion of a macroinvertebrate survey led by entomologist Carrie Elvey of Ohio State University and Steve Slack of Trout Unlimited. The survey was done with the express goal of assessing the current health of Apple Creek and by extension to add to the larger understanding of its health over the years. By surveying the amount and the type of critters, or macroinvertebrates, found in the stream, an estimation could be made of the creek’s health. A healthy stream is a diverse and plentiful one.

Methods & Collection

Three of the HYDRO ’26 team (Amrin, Gabe, and Amelia from left to right) using the Kick Siene net.

Survey sites 1 and 2 (labeled in yellow) along Apple Creek.

The macroinvertebrate survey was done by splitting up and using different methods of collection. Both Dip nets and Kick Siene nets were used to catch the macroinvertebrates, as well as the basic method of picking up a rock and seeing if any macroinvertebrates were on it. This was done for about 20 minutes. Macroinvertebrates were placed into two bins for safe keeping until being separated further into a smaller tray based on species. The different types of species were then recorded. The same process was then repeated at site 2.

Macroinvertebrates separated by species in an ice cube tray.

Carrie Elvey helped the class learn how to identify the macroinvertebrates that were found and how to distinguish between similarly shaped ones. For example, in the top left corner of the ice cube tray above, there are two critters that may seem the same. Upon closer inspection, one of them has visible gills along its abdomen, a characteristic of a mayfly. The other critter without visible gills on its abdomen is a stonefly, as their gill tufts are under their arms.

Figure 1. Apple Creek’s reported annual stream health from 2012 to 2026 as recorded from site #1.

Figure 2. Apple Creek’s reported annual stream health from 2012 to 2026 as recorded from site #2.

Results

Based on our surveys, both of the sites have excellent water quality. Site 1 scored 27 (Figure 1) and Site 2 scored 37 (Figure 2), both above the threshold of 23. In Site 2, we found more of the species sensitive to changes in water conditions and chemistry, including a right-handed snail, dobsonfly larvae, and sow bug, hence the higher score. Both sites had caddis fly, mayfly, stonefly, blood midge, water pennies, left-handed snails, among other invertebrates. While these numbers indicate that the water quality is excellent, the scores have declined since the survey process began in 2012. This could potentially be due to the nearby cement plant, recent storm/flood events, or the history of dredging and oil spills, that could have increased runoff into Apple Creek.