Interested in why fish bite some days and not others?
So were we! One of the side benefits of a rigorous sampling program like we have for the Five-Year Mark & Recapture Study is that we now have robust, quality-checked datasets to ruminate on! The 2010-2011 dataset includes over 1,400 angler hours on the river, and some 1,000 fish events. Since our data is date-specific, we can (and have!) associated it with date-specific environmental variables.
We did preliminary exploration of the dataset using the following variables:
Productivity variables – the ones we wanted to try to get to the bottom of!
- Bull trout productivity (fish per angler hour)
- Chinook salmon smolt productivity (fish per angler hour)
- Wild cutthroat trout productivity (fish per angler hour)
- Wild rainbow trout productivity (fish per angler hour)
- Hatchery rainbow trout productivity (fish per angler hour)
- Steelhead smolt productivity (fish per angler hour)
- Whitefish productivity (fish per angler hour)
- Tagged fish (wild cutthroat + wild rainbow) productivity (fish per angler hour)
- Total productivity, all species (fish per angler hour)
Environmental variables – a cross-section of weather, flow, and temperature variables which speak to common conceptions of when fish tend to bite:
Trip Data:
- Day of calendar year (indicator of early versus late in the season)
- Number of anglers in boat
- Names of anglers
- Total trip time
Flow:
- CFS at Walterville
- Daily mean
- Day-over-day (1-day) change
- Day-over-day (1-day) trend (rising/falling/steady)
- 3-day moving average
- 3-day average change
- 3-day trend (rising/falling/steady)
- 10-day moving average
- 10-day average change
- 10-day trend (rising/falling/steady)
- CFS at Vida
- Daily mean
- Day-over-day (1-day) change
- Day-over-day (1-day) trend (rising/falling/steady)
- 3-day moving average
- 3-day average change
- 3-day trend (rising/falling/steady)
- 10-day moving average
- 10-day average change
- 10-day trend (rising/falling/steady)
- Vida minus Walterville CFS (indicator of EWEB canal operations)
- CFS at Hayden Bridge
- Daily mean
- Day-over-day (1-day) change
- Day-over-day (1-day) trend (rising/falling/steady)
- 3-day moving average
- 3-day average change
- 3-day trend (rising/falling/steady)
- 10-day moving average
- 10-day average change
- 10-day trend (rising/falling/steady)
Water Temperature:
- Vida daily maximum temperature
- Vida daily minimum temperature
- Vida temperature spread (max – min)
- Vida daily mean temperature
- Daily mean
- Day-over-day (1-day) change
- Day-over-day (1-day) trend (rising/falling/steady)
- 3-day moving average
- 3-day average change
- 3-day trend (rising/falling/steady)
- 10-day moving average
- 10-day average change
- 10-day trend (rising/falling/steady)
Weather:
- Moon phase (percent of full)
- Daily maximum air temperature
- Daily minimum air temperature
- Daily mean air temperature
- Daily mean
- Day-over-day (1-day) change
- Day-over-day (1-day) trend (rising/falling/steady)
- 3-day moving average
- 3-day average change
- 3-day trend (rising/falling/steady)
- 10-day moving average
- 10-day average change
- 10-day trend (rising/falling/steady)
- Daily mean barometric pressure
- Daily mean
- Day-over-day (1-day) change
- Day-over-day (1-day) trend (rising/falling/steady)
- 3-day moving average
- 3-day average change
- 3-day trend (rising/falling/steady)
- 10-day moving average
- 10-day average change
- 10-day trend (rising/falling/steady)
- Daily mean wind direction (cardinal direction, 18 divisions)
- Daily mean wind speed
- Daily total precipitation
- Daily mean cloud percentage