Carbon dioxide levels at Salish, Canyon, & Musqueam Creek and its implications on salmon spawning and survival

Abstract

With increasing climate change, CO₂ levels in aquatic systems are becoming more important as high levels of CO₂ can prove to be lethal for salmon survival. In Pacific Spirit Regional Park, Musqueam Creek and Salish Creek have returning populations of salmon that spawn, while Canyon Creek does not. At each creek, CO₂ titrations were done to obtain CO₂ concentration measurements, in order to determine if there was a significant difference in CO₂ concentration between creeks. We predicted that there would be a significant difference between Salish Creek and Canyon Creek, and between Musqueam Creek and Canyon Creek, but not between Salish Creek and Musqueam Creek. Data were analyzed using a single factor ANOVA, and post-hoc analysis was done using Tukey’s HSD test. A significant difference in CO₂ was detected between Salish Creek (M=13.7, SD=2.18) and Canyon Creek (M=9.31, SD=0.87) and between Salish Creek and Musqueam Creek (M=9.92, SD=0.67). Recent restoration efforts and photosynthetic activity in Salish Creek may be contributing to its higher CO₂ levels, relative to Musqueam and Canyon Creek. As all three creeks have mean CO₂ levels within a tolerable range for salmon (8-20 mg/L), we concluded that some factor other than CO₂ must be involved in the differential abilities of these creeks to support salmon.