Pass Lake 'Bows

Willie Bodger

Still, nothing clever to say...
So, I made it to Pass yesterday with Desmond and of the two fish that I caught, the second left me a little present on my apron, about a half dozen eggs. Which brings me to my question, can (or, perhaps do) the 'bows in Pass Lake reproduce there?


Kent Lufkin

Remember when you could remember everything?
Willie Bodger said:
So, I made it to Pass yesterday with Desmond and of the two fish that I caught, the second left me a little present on my apron, about a half dozen eggs. Which brings me to my question, can (or, perhaps do) the 'bows in Pass Lake reproduce there?
I've had the same thing happen with fish at Lenice and Bobby. The fish planted in the Basin lakes were supposed to be triploids and thus incapable of ovulating, as I believe were those planted at Pass.

But nothing is ever as simple as it might seem. In their white paper 'Triploids in Aquaculture', Trout Lodge states that the process of inducing fertilized eggs to become triploid is not always 100% successful. Some of the eggs remain diploid and thus capable of reproducing. Since in practice only females are planted, it would appear that we have run across some diploid females from a planted population that was largely triploid.

That still leaves the question of whether they can spawn successfully. That depends on the presence of diploid males and suitable spawning habitat. I'm frankly not sure whether or not either exist at Pass Lake or the Basin lakes.



Active Member
No they won't reproduce. As far as triploids go, only a fraction of the 'bows planted in lakes like Lenice and Pass are sterile, most of them being normal 'ol diploids.
Triploids cant reproduce, but they often have eggs I believe. A lot of fish at rocky ford have eggs spewing out of them, although they dont, or rarely reproduce. I dont think the males have the ability to fertilize the eggs, so they dont hatch.
Nice meeting you up at Pass yesterday Willie. Its a good thing we headed up there yesterday given I-90 was closed at the summit...I tried the Yak today and (not surprising) like other options right now it is completely blown out. (should have headed back up north) :beathead:

Hope to see you out again sometime...

--hutch (Solomon)

Kent Lufkin

Remember when you could remember everything?
Dan Soltau said:
Triploids cant reproduce, but they often have eggs I believe. . . .
I thought the same thing Dan until I was corrected by another board member a year or so ago. The attached Trout Lodge white paper states: "Triploid females do not produce ovaries and generally do outperform diploid fish . . . " Seems like it'd be kinda hard to produce eggs without any ovaries.


Willie Bodger

Still, nothing clever to say...
Hutch, it was nice meeting you. It'd be pretty cool to see those fish following from the bow of the boat, might have to try that some time...

We were just pulling around various streamers: buggers, sculpins, double bunnies. I almost pulled out some big hairy Muskie flies I've got tied up, but decided against it this time.

And yes, I think eggs without ovaries would be a tricky thing...



Ryan Haseman
I ran into an interesting situation last year at a friends farm pond. It was planted with rainbows a while back that were supposedly sterile. Last year I caught a 22 inch male that squirted milt when I picked him up.
Nice, Miller, nice.

I have to agree with those that say that if it had eggs or milt it wasn't a triploid. I have been under the impression that triploids are not just sterile, they have no reproductive metabolism at all (can we really speak of triploids in terms of male or female?). That's how they get bigger faster; all calorie intake goes to growth, and they don't have to reabsorb eggs or milt when they are unable to spawn in a lake environment, which doe ssound a little hard on anybody.

I also believe that it is correct that only some fraction of rainbows planted in WA lakes by WDFW are triploids. I would guess some lakes get no triploids at all. It's pretty easy to get a copy of WDFW's trout stocking schedule if you want to know for sure what's in the lakes you fish.

Having said that, I doubt there is any successful rainbow spawning at Pass. Does it even have a stream inlet? There are at least intermittent stream connections at some of the Basin lakes (certainly at Lenice/Nunnally), so there might be some limited spawning going on (and probably at RFC too), but I would guess that hatchery rainbows have pretty limited reproductive success. I would imagine that most hatchery-trout lines are significantly domesticated.

I do have to say that I am troubled by the idea that not all of the "triploids" WDFW plants are successfully "sterilized" (they are starting to consider stocking their "sterilized" triploids in streams). Troubled, that is, but not altogether surprized. It seems like there's always more to the story with those chaps, doesn't it?
There are actually two ways of producing triploids. The cheapest and so most common is to apply heat or electroshock to the eggs. This is the least effective and there will still be substantial #'s of unaffected fish in the batch. The second way is to treat the eggs with testosterone. Much more effective but expensive and there will still be some unaffected fish. The most effective and most expensive is to do both yielding very few unaffected fish. this link goes into detail. page 5 or 6

For normal female trout the attempt to spawn is very stressful. They produce eggs which must later be reabsorbed. This is the biggest cause of mortality amoung female rainbows, which are typically the largest fish in a population. In some places with no spawning access artificial streams have been built so that those big females can spawn, even if no eggs ever hatch, and so live longer. One example is at Logan Lake in BC. The channel is about 200 yards and water is pumped up from the lake and runs back down making a little stream. The stream is dry after the fish spawn. Some natural spawning occurs when good gravel is available on a lake bottom (rare), but this is seldom enough to benefit many fish. There is no stream inlet or outlet at Pass big enough to be useful, but there are springs which may create spawnable areas. I have also seen bows attempting to spawn in the gravel off the launch and near the big cove along the road where there is some gravel bottom.

Old Man

Just an Old Man
Maybe this is what is wrong with me. Ever since I got older I got fatter and my desire to spawn is waning. Or in my case the desire to fish.:( :(


Note to the Mods. It is alright to delete this if you feel that it isn't within the lines of this thread. I was just trying to poke a little humor into this worn out subject.

Note to Old Man Jim: How can you wear it out if you aren't using it?


Active Member
I recall reading somewhere that male triploids are culled and only females are planted. The apparent concern is that males, which would have an advantage in size over normal diploid males, might attempt successfully to spawn with fertile diploid females which would result in infertile eggs. Of course, this would only be of concern where natural spawning can occur. I suspect it may be just a general precaution.