On Saturday, November 10, 2018, CWCAP citizen scientists collected data from salmon carcasses in the Piper’s Creek Watershed. Each fall (view salmon return numbers since 2014), CWCAP surveys each carcass to determine whether fish are fully spawned, partially spawned, or not spawned at all. This is one measure of the heath of the adult salmon return. Through early-mid December, CWCAP will be conducting Saturday surveys until no more un-sampled salmon carcasses are found. Around Thanksgiving time has been within a few days of the actual peak of live activity for at least the last 5 years.
The following table summarizes the results from our first survey day.
- Of the 20 Coho sampled, 7 were remnants and could not reliably be sexed. Of the 13 Coho that were sexed, all were females. Of the 13 females, 7 were partially or fully spawned. Of those 7, 2 Coho appeared to be fully spawned. All Coho where the caudal region was intact were clipped hatchery fish.
- Storm water flow rate: it is known that extreme energy and water volume associated with storm water moves dead adult salmon from the system to Puget Sound. Fish flushed from the system cannot be estimated and are not represented in this data.
- Predators/Scavengers: many salmon carcasses are found each Fall in the brush and wooded areas near the creeks. Without a comprehensive search, it is likely that the survey team misses numerous carcasses during surveys due to predators and/or scavengers that drag salmon from the near-creek vicinity and are therefore not represented in the data.
- This data represents all fish encountered and processed that have already died after entering Piper’s Creek and Venema Creek. Each Chum salmon dies in more or less 10 days after entering Pipers Creek’s freshwater, whether spawned or not. Since this survey opens each dead fish by incision along the belly to examine its relative spawning success, we can be certain that fish haven’t been double-counted from one week to another.
- * Resident cutthroat trout (O. clarkii) are not part of the current survey design. The methods used in this survey do not accurately sample for the presence of resident cutthroat trout, but numbers are listed here as incidental information only.
- Fish are sampled from dead carcasses taken from Pipers Creek and Venema Creek and returned to sample location.