Running with the Rot Squad in Headwater Streams

Date: March 24, 2017 Author: EcoSpark Categories: Latest

A new citizen science initiative to examine decomposition in headwater streams!

This blog was contributed by guest writer, Brian Kielstra.

I’m an aquatic/landscape ecology PhD student from the University of British Columbia. I’ve been working with EcoSpark since last summer to develop a citizen science protocol to examine how an ecological process, decomposition rate of cotton strips in headwater streams, might change when land uses in watersheds are different. We developed a protocol, piloted a training session, and sent out two teams – affectionately called the Rot Squad (thanks, Les Stanfield!) –  try the methods for themselves.

Group photo of the pilot Rot Squad

The pilot Rot Squad, October 2016.

The Importance of Headwater Streams

Many people have some understanding about watersheds. When it rains, water tends to move from higher elevations to lower elevations. If enough rain were to fall in your neighbourhood, you might be able to trace its flow all the way to a slightly larger stream. If you followed the flow of that slightly larger stream, it would meet with an even larger stream! All of the land that moves water into a stream is called its watershed.

There are many small streams in a watershed. In fact, if you added up all of smallest stream lengths (the 1’s below), it represents 70% to 80% of the total stream length in a watershed! Since most water eventually ends up downstream, it makes sense to have a good understanding and protection of headwaters. However, most legislation focuses on protecting downstream habitat.


A stream network. Headwater streams are the 1’s. Larger numbers indicate larger streams. Source:

Examining Rot Rate

Along with EcoSpark, we are trying to understand how decomposition rates are different from one headwater stream to another. Decomposing materials (e.g., leaf litter) are recycled back into the plants and animals that make up complex and diverse food webs.

We are using a recently developed standardized cotton strip method to measure decomposition rate. We leave cotton strips in the stream for three weeks and then pull them apart with a machine called a tensiometer. Its resistance to breaking shows how much it decomposed. We expect that healthy microbial communities are able to degrade materials faster.


A 2.5 cm x 8 cm cotton strip that was left for three weeks in a stream and then pulled-apart. 

Volunteer for the Rot Squad

We are currently looking for volunteer crew members to join the Rot Squad to deploy these cotton strips across headwaters streams in southern York Region on Saturday April 8th, 2017. There is also an opportunity to be trained as a crew leader on Saturday April 1st, 2017. To learn more and to register, please visit the Rot Squad webpage

We hope that this work will engage citizen scientists to learn about the importance of headwaters and provide valuable data for larger research projects.

BrianKielstra_circle.jpg About the Author: Brian Kielstra is an aquatic/landscape ecology PhD student from the University of British Columbia with Dr. John Richardson. His research focuses on the cumulative impacts of headwater stream loss on downstream ecosystems. Brian is interested in how ecosystems are quantified and understanding how they are impacted by patterns and processes occurring at different scales.

This pilot project is funded through the Ontario Trillium Foundation with in-kind support from the University of British Columbia and the Toronto and Region Conservation Authority.

Ontario Trillium Foundation Logo    TRCA-CorporateLogo2012__1_.gif