COMPARING THE SKAGIT RIVER TO OTHER NORTHWEST RIVERS - STEELHEAD DECLINE AS RELATED TO HATCHERY RELE

Discussion in 'Steelhead' started by 808steelheader, Jan 31, 2013.

  1. More questions... Once a predation problem is in place and evident, how much time, in years does it take for the predator population to go back down or stabilize back to where it was?

    If there is a predation problem from outgoing hatchery smolts eating wild smolts--- Points to hatcheries as the problem
    If there is a predation problem in the straight from over abundance of "food" for other marine predators--- Points to hatcheries as the problem
    If there is a genetic degradation in wild fish--- Points to hatcheries as the problem
    If there is not enough food in the ocean for wild fish and them competing with hatchery fish--- Points to hatcheries as the problem

    The only problem that would seem to not be hatchery related would be pollution of some kind, or maybe water temps, or lack of cover for outgoing smolts to "hide" from predators.

    All "known" problems seem to lead back to hatcheries.
     
  2. Are we talking about the same predators that preyed on the once "mighty" runs of wild fish smolts? Or did these predators just show up after the hatcheries were built?
     
  3. The theory is that hatchery smolt tend to exit the river in a shorter period of time, and in greater concentration than do wild smolts, and preditors have learned to key on them. Like the Caspian Turns @ the mouth of the Columbia.
     
  4. Adding to what Chris said… From what I understand, hatchery smolts survival skills have them learn how to survive in a hatchery tank void of predators. The only skill they pick up is how to survive extreme overpopulation. We already know the survival rate of hatchery smolts vs wild smolts plummets. When released by the thousands out into the rivers, they are “sitting ducks” so to speak for every sort of predator. Over time and adding the compound effect, the hatcheries basically become glorified feeders for lots of downriver predators. This is a little about what David Noakes was pointing out. We want more fish, so we put more hatchery retards out into the rivers, and expect them to come back. When all we are doing is hurting the runs by exploding the predator populations.
     
  5. Chris -
    The problem with the terns on the Columbia is more related to the Corp of Engineers using the sand spoils from all the dredging they do to keep the main channel open for shipping to build islands on the river. Those islands (especially Rice) provide near ideal nesting grounds for the terns and Cornomants. In fact if I recall correctly Rice supports the largest nesting colony of Caspian tern in the world.

    Curt
     
  6. Has anything like this been witnessed in Puget Sound?
     
  7. I do not know



    That may have been a bad analogy, and I'm sure is up for debate, but it was the easiest one for me to reference.
     
  8. The tern colony on Rice was removed some time ago; http://www.birdresearchnw.org/Project-Info/Study-Area/Columbia-Basin/Rice-Island/default.aspx. Still the island is an artificial nesting site for other birds.
     
  9. Kerry -
    Thanks i had forgotten that the colony was moved (damn it is hell to get old)

    If I recall correctly east Sand is downstream near Chinook - still in the estuary. However the key point here is that the predation problem was compounded by man's poor ecological choice in creating those sand spoil island/potnetial nesting grounds.

    Curt
     
  10. Chris/TallFlyGuy-
    Let's talk about the role of hatchery steelhead in prey/predation relationships in the Skagit for a minute. I'll focus on the 4 points that TallFlyGuy posws but to be fair I should state that while have not targeted hatchery winter steelhead in years I do appreciate that having them in the river gives additional oopportunties to some blue ribbon trout fishing on the Skagit.

    1) "If there is a predation problem from outgoing hatchery smolts eating wild smolts--- "

    First there is no problem of hatchery steelhead smolts eating wild steelhead smolts, parr or fry. The wild smolts are nearly the same size as the hatchery fish (6 inches verus 8 inches) so the in the river a healthy wild smolt would not likely be prey for a hatchery smolts. In the spring of the year the fry of the year will be eggs either in the gravel or still in the females and not likely prey. Becasue of the high flows and cold water temperatures that are the norm in the Skagit during May and June the wild parr are still hiding out in their overwinter habitats well away from the migrating hatchery smolts and not likely prey.

    During the late 1990s there was concern that given the size of the hatchery steelhead smolts that they were major predators of wild salmon smolts; especially the ESA listed Chinook. Several years of sampling the stomach contents of free swimming hatchery smolts captured in the river. The rivers sampled included the Skagit, Green and Deshcutes with no Chinook or coho found in their stomachs. To be fair pink and chum fry were found and in some cases quite a few in an individual hatchery smolts. On the Skagit one was more likely to find fir needles in the hatchery smolts stomach than salmonids.

    Given the common preception of how unfit hatchery smolts are it could hardly be a surprise that they aren't every effective predators.

    2) "If there is a predation problem in the straight (sic) from over abundance of "food" for other marine predators..."

    A common negative associated with hatchery steelhead smolts is that they attract predators either in the river or the sounstraits. Again lets look atthe specifics of the Skagit. In the spring the Skagit is a major highway for smolts (hatchery and wild) on their way to the salt. In addition to the 300K of so hatchery winter steelhead on an average year there will be 1.29 million hatchery Chinook and coho and 500K to 1 million sockeye smolts. The Skagit is a major producer of wild salmonids so in additon to the 2 to 2.5 million hatchery salmonids there will be lots of wild salmonid smolts. The number of of Chinook and coho smotls will vary from 3 million to more than 10 million each spring, on good years there will 10s of million pink/chum fry and of course there will be 200 to 250K steelhead/cutthroat/bull trout smolts.

    With 6 to 10s of millions hatchery and wild salmonids migrating downstream in the spring of the year the less then 300,000 steelhead smolts account for sall poriton (from less than 1% to maybe as much as 5%) of the smolts in the basin. As a magnet to predators it is hard to imagine them attacting significantly (detectable) numbers of additional predators. Especially given the hatchery steelhead contribution to the overall abundance from year to year. This would also apply to the near marine waters (Puget Sound).

    3) "If there is a genetic degradation in wild fish--- "

    Over the last 40 years at least the genetic profile of the wild Skait steelhead (including hatchery "markers") has remained unchanged. This is in spite of reduced temporal and spacial over lapp between potential hatchery and wild spawners. Over that same time period the abundance/survival of the basin wild steelhead has ebbed and flowed independent of the so-called genetic degradation of the wild populations. In spite of several studies there is no information supporting that "genetic degradation".

    4) "If there is not enough food in the ocean for wild fish and them competing with hatchery fish--- "

    The fact through out the Pacific we see widely differing steelhead survivals points to an ocean that is hardly uniform withfish from different regions having different survival as they migrate through different ocean regions and at different times. While it is unlikely that today there are more steelhead smolts in teh ocean than say 200 years ago there is little doubt that with themassive numbers of hatchery pink and chums reelased in Alaska and Asian there likely more total salmonids using the ocean today than 200 years ago.

    It seems to me that eliminatng the release of hatchery steelhead in a single river or even in a region would not make much of dent in the total over all salmonid abundances in the ocean. That coupled with the fact eliminating hatchery smolts from a river has a mixed track record in postive population rebuilding it would seem to indicate that ocean abundance of steelhead (hatchery and wild) is not a major driver in their survival.

    While these kinds of issue are important and those kinds of interactions should remain on the radar screens of all for at least the Skagit wild steelhead they do not seem to be the smoking gun that is limiting their numbers.

    Curt
     
  11. I was just trying to answer Wayne's question, thanks for the response though.
     
  12. Curt, this is hard for me to believe. I do not believe I am the only one who has hooked many hatchery smolts on a swung fly that resembles a smaller smolt. Adding to that, I have also caught whitefish, bulls, and cutts on the fly as well. All on flies that resemble smaller fish etc. How long the smolts stay in the river before moving out, and where they go before going downstream is up in the air. Is it not safe to say they can go upstream as well as down, and therefore forage on smaller fish like salmon and steelhead smolts? You point out the studies above, but again, I think they are a little suspect given the fact that my friends and myself have caught many, Mucho smaller smolts on swung flies resembling minnows etc. I also see many people use spinners to catch smolt after smolt.

    Again, artificially adding 10s of million of hatchery smolts into a system and out into the straight, and saying there is no ecological effect on predator populations seems very hard to believe.

    I am not sure the history of how many and what species of steelhead smolts have been put into the Skagit, but if the same species is caught and then artificially reproduced in a hatchery, and then let go, how do you "genetically" differentiate between the two fish when they come back from the ocean....One with an adipose and one without?

    Again, artificially releasing 10's of millions of smolts into a region and believing that no ecological effects take place on feed fish etc, is a hard truth to swallow. If you believe this, then you would have to believe the inverse to be true as well. If millions of smolts were put into a system, with unlimited amount of food for them, and zero predators...we would get the same returns. Very tough to believe this.
     
  13. TallFlyGuy -
    Again I must of written poorly -

    Of those 10s of millions of Skagit molts the vast majortiy are wild. More to the point depending on the abundance of the pink and chums (all wild) the hatchery steelhead represent as lttle as less than 1% to a amximum of 5% of the total smolts (hatchery and wild combined) exiting the Skagit each spring.

    Not seeing how the relatively low abundance (of the total smoltnumbers) of hatchery steelhead is contributing to the attraction of predators.

    I'm also struggling with where all these predators are coming from. Those smolts are available only a few months of the year and any predator will have to "make a living" the rest of the year. Unless the spring prey abundance is the bottleneck for the local predators don't see how the smolt abundance will lead to an overall increase in predators. Unlike the lower Columbia there are no seasonal concentration of avian predators on the Skagit at the time of smolt migration.

    Curt
     
  14. Curt,

    How many rivers are artificially planted that dump into the Straits? What is the total number of hatchery smolts from all of the rivers entering the Straits? How or where did you get the number 10s of millions of wild smolts on the Skagit heading out to sea? If this were the case, shouldn't you be able to sit on the banks in April and watch 1000s and 1000s of smolts go by you?
     
  15. TallFly Guy -
    I tried to be clear about the Skagit wild smolt numbers. The Chinook and coho wild smolt numbers come from a smolt trap located at river mile 16. As I mentioned a couple million Chinook migrants a year is pretty common (at times in excess of 10) and 3/4 to 1.5 million coho are also the "norm". Of course the wild migration numbers on the Skagit are boosted a lot by the pink and chum.

    While the "official" forecasts for this year's runs have been released (will see those March first) I full expect the wild pink forecast to be somewhere between 1 and 2 million adults. For this excercise let's assume it will be 1.5 million. Several studies have found that it is common for pink fry to adult survivals to be from a few tenths of a percent to bit over 1%. Let's assume that it was 1%. That means last spring as many as 150 million pink fry left the Skagit River (again all wild)!

    And yes one can watch 1,000s and at times even 10,000s wild salmonids swim by a given point during the out migration.

    The important point is that while it is great to gather as much information as studies across the region it is also important to try to put that information in context of the best local information.

    Curt
     
  16. I don't know how the predation thing works up in Washington. In the Trinity River in NorCal, the best flies at the time of smolt release is a 5-7" smolt pattern. The browns decimate those fry when they are released. They come back at the right time of the year, every year. surprisingly adaptive behavior for a stupid fish.
     
  17. The man made Everett jetty is also a nesting area for these terns
     
  18. Curt,

    I appreciate the feedback and discussion here. I am trying not to be or sound difficult. I am just a fly fisherman that is fed up and trying to piece the puzzle/mystery together.

    From what I understand, the coho and pink salmon populations are doing just fine, but the wild steelhead populations are plummeting. From the few research articles and studies done with radio transmitters, I have noticed, as Salmo pointed out, most of the smolts survive from the time they are smolts in the river down to the estuary/straight. As high as 90% and as low as 68% survival. However, from the time they go from estuary to the time they go to the ocean, the smolts survival falls off the charts. How could this be, if salmon populations are doing fine, but steelhead are “up and dying”? As one article pointed out, steelhead travel/live in the first 100 feet of water, and salmon tend to live deeper. If this is the case, then wouldn't they be much more susceptible to predation in the first 100ft of water than below 100ft? Seals, birds, larger fish, etc?

    I think fish survival relies on two things outside of environmental issues, being able to eat, and not being eaten. If salmon are doing fine then I don’t think we can look at environmental issues, we have to look at predation and feed. I think WDFW and the other powers that be know this. So the easiest, cheapest, least problematic, (until Occupy Skagit) predator to get rid of is us the fishermen. This plan doesn't seem to be working.
    In Idaho, Lake Pend Oreille had a similar mystery with their kokanee. The kokanee populations were plummeting. The conclusion was too many predator fish eating the kokanee. Their solution was to kill off as many predator fish and pay fisherman to do the same. Now it appears the kokanee are rebounding and doing well. Not sure how or if it is even possible to kill off predators that eat steelhead smolts as we are talking about birds and seals etc.
     
  19. TallFlyGuy-
    I agree that these kinds of discussions are a good thing. They help provide lots info to the various readers and force all of us to think about this kinds of issues.

    That said I'm not sure how germane the Pend Oreille kokanee/predator discussion is to this thread. As you know the Pend Oreille kokanee are an exotic gaining access to the lake during the 1930s. As often is the case in their new habitat the population exploded. By the late 19400s/50s it was support a significant commercial fishery (caugth with hand lines) with the best years producing up to a million kokanee harvested. In addition to the commercial fishery the kokanee provided forage for the larger fish predators. Ultimately it produced world record bull trout (a native species) and rainbow (an exotic Kamloop stock from Gerrard). Things began going south in the late 1950s/early 1960s due to habitat loss (mostly spawning areas for the kokanee) following the conctruction of a dam (Albeni?). Things when from bad to worst following the introuduction of mykiss shrimp during the late 1960s. It was thought the mykiss would supplement the forage base from the kokanee leading to the larger fish (a common belief during the era).

    The problem with the mykiss was they ate the same zooplankton that the kokanee did. In addition mykiss are light sensitive and go deep (depths of 100s of feet) during the day effectively moving out of range of the kokanee. The result was that the kokanee had a serious forage competitor causing a decline a kokanee abundance. To crop the mykiss lake trout were introdcued. They would following the mykiss to the depths result in an explosion offast growing lakers (at least until they reached a size that mykiss were too small to be a significant forage item). Of course the lakers looked for a new forage base - the kokanee.

    The end result was the kokanee were caugth in the deadly situation of having a significant spawning habitat loss, a serious food competitor and a string of predators (bull trout, rainbows and lakers). Things had unraveled to the point that the managers were looking at a total fisheries collapse. They were left with trying to manipulate the various exotic species (kokanee, mykiss, rainbows and lakers) in to some sort of balance for fisheries benefits.

    BTW -
    Pend Oreille is not an iolated example of kokanee collapse following mykiss introductions and the resulting prey/predator problems (Chelan and Flathead are other examples).

    Curt
     
  20. Curt,

    I remember standing on our boat on lake Pend Oreille and looking out across the lake and seeing, what seemed like millions of kokanee, jumping and feeding on the surface of the lake. This was back in the mid to late 90's. A few years later and as you said, they were looking at a total collapse. One of the first things they did was close the fishery, and then they took massive action to try and help the fishery out. Commercial fishing vessels were called in and 1000s of lake trout and other predators were netted. Gerrard rainbows, and lake trout were caught by fishermen and then turned in for a bounty. I think the problems with the kokanee parallel the problems with steelhead in some ways. The two main variables for survival, feed and predation, were wiping out the kokanee, and the powers that be took massive action to help the kokanee out.

    Thinking outside the box a little, if we were able to construct a huge floating enclosure of some sort 1000x1000x50ft, and put 1000 steelhead smolts in it... pulled it into the Strait, then the Ocean, and fed the steelhead smolts for a couple years...would the fish up and die? I don't think so. They would be protected...void of predators and having all the food they need. Of course, this is just for the sake of example, I really don't think this is possible. It does show how when you eliminate the two variables of food and predation, the fish survive. Back to the Idaho example, the fish and game along with the scientists, didn't sit around, scratch their heads, tell people the problem was impossible to figure out, and throw money at "mystery" problems. They took massive action to correct the food and predator problem. Why is this so hard for the state of Washington to do the same?
     

Share This Page