A watershed is an area of land that catches rain, snow, and other sources of water and drains into a body of water (Connors, 2008). They can combine with other watersheds to form a network of rivers and streams that drain into even larger bodies of water. What most people don’t know, however, is how important watersheds really are. Watersheds gather everything from rain and snow to run-off from drains in cities; since the collected water ultimately drains into other oceans, it is important to consider the downstream impacts. Of course, everything upstream ends up downstream, and we have been affecting the water quality of multiple watersheds in British Columbia by contributing to pollutants in our water run-offs (Connors, 2008). In turn, this can affect many organisms living in the watershed’s streams and rivers.
In many cases, there are things we can do in order to minimize this impact. By managing a watershed, we would be protecting the lake, river, or stream that the watershed runs in to (Journey with Nature), increasing the survival chance of animals living in these locations.
A study done by Ogston and colleagues focused on habitat restoration in the Chilliwak River watershed floodplain habitats in British Columbia. Floodplain habitats are habitats in the watershed area such as sloughs, side channels, beaver ponds, and other permanently/seasonally flooded areas, and are important for many species of fish and amphibians (Ogston et al, 2014). In particular, floodplain habitats are important for juvenile coho salmon (Oncorhynchus kisutch) because they use it for both rearing and overwintering. However, extensive logging in the Chilliwak area has resulted in extensive loss of floodplain habitat and salmon numbers were negatively impacted as a result. Habitat restoration in watersheds was thought to help bring their numbers back up.
By constructing and reconnecting floodplain habitat to the main stem of the watershed, they found that the juvenile coho salmon out-migration to a larger body of water increased from 27% to 34%, indicating that by restoring the habitat, we can effectively enhance the number of juvenile salmon migration (Ogston et al, 2014). This is important to ensure that the salmon can migrate to the ocean and return once they are ready to spawn.
Overall, restoring habitat in watersheds is very important when it comes to the survival of species such as the coho salmon. Of course, successful watersheds depend on an informed public to make the right decisions when it comes to the environment.
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Ogston, L., Gidora, S., Foy, M., Rosenfeld, J. 2014. Watershed-scale effectiveness of foodplain habitat restoration for juvenile coho salmon in the Chilliwak River, British Columbia. Canadian Journal of Fisheries and Aquatic Sciences, 72(4): 479-490. doi: 10.1139/cjfas-2014-0189
Connors, T. 2008. [Internet]. How watersheds work. Science: How Stuff Works. [cited 2016 Feb 03]. Available from: http://science.howstuffworks.com/environmental/conservation/issues/watershed1.htm
Journey with Nature. [Internet]. The Nature Conservancy [cited 2016 Feb 03]. Available from: http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/indiana/journeywithnature/watersheds-101.xm