Trapping Success Despite Low Return of Steelhead

  • Adult steelhead
    Licensing: 
    Creative Commons Licence
    Attribution: 
    Angela Carhart and Sarah Barnes
  • Fish Creek Weir
    Licensing: 
    Creative Commons Licence
    Attribution: 
    Marika Dobos
  • Marked Female
    Licensing: 
    Creative Commons Licence
    Attribution: 
    Angela Carhart and Sarah Barnes

The Lochsa River is managed as a wild steelhead refuge that does not allow steelhead fishing and does not have hatchery steelhead stocking.  A number of other drainages across the state are manged the same way such as the Middle Fork Salmon, South Fork Salmon and Selway rivers to name a few.

In the Lochsa River, IDFG has run an adult steelhead weir (trap) on Fish Creek since 1995. Because the trap has operated for nearly 25 years we can use information from there to say a lot about Idaho's wild steelhead. These fish migrate up in the spring time, flows are at their highest and trees are floating downstream making it very difficult to catch fish.  Since we can't trap every single fish heading up Fish Creek to spawn, we mark fish that are captured moving upstream and try to recapture them after they are done spawning moving back downstream.  The number of marked and unmarked fish we catch after spawning (i.e., kelts) are used to estimate the total number of fish that made it upstream of the weir to spawn.  

Despite the low number of wild steelhead returns this last year, we still caught some adults at Fish Creek weir.  Given the number of unmarked and marked fish we caught, we estimate there was a total of 48 adult steelhead that made it up Fish Creek to spawn.  Since 1995, an average of 152 adults made it up Fish Creek to spawn with the highest number being close to 500 in 2011 and 2015.  But we've also seen years similar to 2019. We've had three previous years where we estimated less than 50 fish returned to Fish Creek. 

These fish are pretty amazing creatures to work with and we're fortunate to have a place like Fish Creek to study them. We'll be back at it next February building the weir again to collect more information on Idaho's wild steelhead.