This is a draft document which will be continually updated. We are looking for feedback, especially if there are any life cycle timings that do not align with your knowledge of the CU. For feedback and questions please contact Stephanie Peacock (speacock[at]psf.ca) or Sam Wilson (swilson471[at]gmail.com).
We have estimated the timing of four key life stages for Conservation Units (CUs) of five Pacific salmon species and steelhead trout 1. PSF will be using this information to determine the relative exposure of CUs to climate changes in freshwater across four freshwater life stages: eggs/alevin, juvenile freshwater rearing, adult freshwater migration, and spawning.
In order to estimate these four freshwater life stages we collated information on the timing of four life stage events. These events are:
For each of these life cycle events, we have estimated the start and end of the timing window as the 2.5th and 97.5th percentiles of the cumulative timing from available data for the CU.
Fry migration and ocean entry timing were determined through a literature review and compilation of historic data. Migration data were typically collected using rotary screw traps, incline plane traps, and fyke nets. Adult run timing was determined from reports of catch (e.g., Tyee test fishery; Albion fishery) assigned to CUs based on genetic stock identification. Spawn timing (except for steelhead) was estimated for each CU using NuSEDs data on start, peak, and end spawn times for river populations within that CU. Run timing and spawn timing for steelhead trout were collated from historic reports. In these reports, timing was typically determined using radio telemetry.
Although these sources represent the best publicly available information, the data on timing are limited. There are many CUs for which we were unable to find information on the above life cycle events, and CUs with information often have data from only a single location for a handful of years. As such, we are seeking input from experts to ensure the information is accurate. We would appreciate any feedback on the timing of life cycle events presented here, including suggestions for additional data sources (e.g., for run timing or for spawn timing in the Transboundary region).
Using these four life stage events we estimate four freshwater life stages:
Incubation - begins with the 2.5% percentile of the cumulative spawn timing, and ends with the 97.5% percentile of the cumulative fry migration.
Freshwater rearing - If juveniles rear for more than one year, this stage will span the whole year. If migration takes place within the first year (0+) then freshwater rearing begins with the 2.5% percentile of the cumulative fry migration, and ends with the 97.5% percentile of the cumulative ocean entry.
Upriver migration - begins with 2.5% percentile of adult freshwater entry, and ends with the with the 2.5% percentile of spawning.
Spawn timing –begins with the 2.5% percentile of the cumulative spawn timing, and ends with the 97.5% percentile of the cumulative spawn timing.
The datasets used to generate the following life cycle charts are available HERE. Descriptions of each file are located in the readme file in that folder. Briefly, the number of each file depicts the order that the data were summarized in, with:
1Life_cycle_timing_by_reference sheet showing the raw data entered from each reference.
2Life_cycle_timing_by_location is then a summary by location of all the information in 1Life_cycle_timing_by_reference sheet.
3Life_cycle_timing_by_CU is a summary of the location-specific information from 2Life_cycle_timing_by_location.
4Life_cycle_table_by_CU shows the data used to generate the life cycle tables below and includes raw data from 3Life_cycle_timing_by_CU and extrapolations.
If you have feedback or questions please contact Stephanie Peacock (speacock[at]psf.ca) or Sam Wilson (swilson471[at]gmail.com)
Conservation Units have been defined under Canada’s Wild Salmon Policy as ecologically and genetically unique groups of salmon that, if extirpated, are unlikely to be recolonized within an acceptable timeframe. Steelhead were not formally included in the Wild Salmon Policy or work led by DFO to define CUs for salmon. However, past work has been done to define 36 provisional CUs for steelhead in BC, which characterize the biodiversity of steelhead in BC using similar methods to those used to define salmon CUs (Tautz et al. 2011, Parkinson et al. 2005). Future work is needed to review and potentially refine these steelhead CUs based on more recent research and data to ensure they fully capture the diversity of steelhead in BC and meet the Wild Salmon Policy’s definition of a CU. We have used provisional steelhead CUs from Tautz et al. (2011) for the Skeena Region and from Parkinson et al. (2005) for all other Regions when summarizing timing data.↩︎