Water Rangers was given the exciting opportunity to join the Rideau Valley Conservation Authority on a City Stream Watch Fish Sampling Session at Steven’s Creek. Our trip served two purposes, to see how the fish are collected and studied, and to compare our testkit instruments to the Conservation Authority’s professional devices.
Starting The Day Off: Fish Sampling
After arriving at the creek, we put our hip waders on and got straight to work. We started by bringing in the nets to see what had been collected the day before. The Rideau Valley Conservation Authority (RVCA) checks these nets and records data daily and the locations of the nets are changed weekly.
We removed all of the fish from the net and placed them in a large container of oxygenated water. We don’t want to harm the fish – just study them – so we tried to work quickly so they could be released as soon as possible.
Rosario Castañón, a marine and freshwater biologist from the RVCA was helping us out with the fish identification. She let us know about the defining features of certain types of fish and helped us understand these features in practice.
After identifying and separating the different types of fish, we weighed each one and measured its length. We had collected about 10 of a fish known as “pumpkinseed” because of its distinct orange dot on the distal end of the gill opercular cover. Since there were many of them, we weighed and measured the largest one and took the average weight of the rest. Once all the fish had been released, we set the net up again for the next day.
Once all the fishing gear had been cleaned up, we decided to paddle down the river to look for invasive species. We found quite a few, some of which included curly leaf pondweed and European frogbit. Rosario mentioned that the water quality is considered “good” in the headwaters, which are dominated by wetlands and forest cover, but as you move downstream through the system, water quality shifts to “fair” and “poor.” This is because the land cover conditions surrounding the creek are being dominated by agriculture and small residential areas. More details on the water quality within the watershed can be found in the Lower Rideau Sub Watershed Report.
A True Test: Comparing Our Equipment to the RVCA’s Probes
The final exciting thing we got to do was compare our instruments to the professional level equipment. We were so happy with the accuracy of the results! Using a pH probe, the RVCA got a reading of 7.36, while we measured a reading of 7.5, giving us a percent difference of 1.9%. Our dissolved oxygen test gave us a reading of 4.5 compared to the RVCA’s 4.45, making the percent difference of 1.1%. We made a full Water Rangers entry with these results!
We aim to make sure our instruments are within 5% of the professional probes, so we were very pleased. Learn more about our testkits.
All in all, it was a great day! Water Rangers would like to thank Rosario, Fiona and the Rideau Valley Conservation Authority for having us.