Sterile vs. Non sterile predator induction

[Cowboypirate]

The whole " musky in the Uinta" thread has got me pondering the biology and ethics of non native predator introductions , especially pertaining to sterile vs. Non sterile. I have mixed emotions on the whole process. 

For instance the choice to introduce a non sterile predator means long term cost to maintain that predator base through hatchery and stocking with what I would assume is a very high mortality rate.

But going non sterile of course means no control of population growth.

I would love to hear some thought about this. I am by no means a biologist so if those thought were back up with some science or links to good reading that would be great- but I am fine with personal opinions. Looking to get better educated on the subject.

[fishskibum]

The whole " musky in the Uinta" thread has got me pondering the biology and ethics of non native predator introductions , especially pertaining to sterile vs. Non sterile. I have mixed emotions on the whole process. 

For instance the choice to introduce a non sterile predator means long term cost to maintain that predator base through hatchery and stocking with what I would assume is a very high mortality rate.

But going non sterile of course means no control of population growth.

I would love to hear some thought about this. I am by no means a biologist so if those thought were back up with some science or links to good reading that would be great- but I am fine with personal opinions. Looking to get better educated on the subject.

a really interesting read on the history of stocking programs the effects on native fish and how the thoughts on it have changed over time

[wormandbobber]

Introducing sterile tiger musky is only different from introducing fertile brook trout in that one can reproduce and one cannot. From a fisheries management standpoint, the sterile non-native stocking is often better because of the ability to control population density with stocking. Stocking nonnatives that are fertile into environs where reproduction and recruitment are not possible can also be good but it is not always known prior to stocking whether reproduction is possible or not.
https://www.tandfonline.com/doi/abs/10.1...15.1035467

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https://www.hatchmag.com/articles/tiger-...7024000000

[Envenomation09]

As an aspiring biologist, using sterile species makes sense to me from a management perspective. The population is easily controlled and so we can determine biomass goals, etc. 

But as an angler, it makes me . We have to continually dump money into fisheries if we want triploid rainbows or sterile hybrids. It feels lazy. What I most of all hate is to see fisheries that essentially self sustain replaced by tiger trout. We put tiger trout everywhere! Let's put that same energy and money into maintaining quality populations of fertile fish especially brook trout. I want diversity in our recreational fisheries. The DWR, for instance, will not manage northern pike even though many many states have no problem managing excellent northern pike fisheries that require no stocking. Think of Navajo Lake that is filled with chubs, if pike were added things could change. But the DWR wants to use tiger musky that are costly to grow, will not self sustain, and are extremely difficult to catch, instead. Everything else dies in there each winter, so maybe let's try an Arctic species??

Now, I don't think there is always a solid, simple solution when managing fisheries, but I do believe there is more wiggle room than the DWR is willing to admit when they think of what predator fish people want. I have a big list of fish I'd love introduced to Utah if I had my pick (flathead catfish as carp control anyone?) but I recognize that is unrealistic! I think Utah really needs to get the Colorado squawfish/pikeminnow to be used as a sportfish like they have the round tail chub. It would be an amazing predator and a native! I enjoy our fisheries in Utah but an emphasis on the same few species and put and take waters always disappoints me. 

There's my ramblings on Utah fish, it probably shouldn't be taken too seriously but I love our fisheries dearly and hope they can always improve.

[Cowboypirate]

The whole " musky in the Uinta" thread has got me pondering the biology and ethics of non native predator introductions , especially pertaining to sterile vs. Non sterile. I have mixed emotions on the whole process. 

For instance the choice to introduce a non sterile predator means long term cost to maintain that predator base through hatchery and stocking with what I would assume is a very high mortality rate.

But going non sterile of course means no control of population growth.

I would love to hear some thought about this. I am by no means a biologist so if those thought were back up with some science or links to good reading that would be great- but I am fine with personal opinions. Looking to get better educated on the subject.

a really interesting read on the history of stocking programs the effects on native fish and how the thoughts on it have changed over time

Thanks looks like a great resource. I will chase one down

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Introducing sterile tiger musky is only different from introducing fertile brook trout in that one can reproduce and one cannot. From a fisheries management standpoint, the sterile non-native stocking is often better because of the ability to control population density with stocking. Stocking nonnatives that are fertile into environs where reproduction and recruitment are not possible can also be good but it is not always known prior to stocking whether reproduction is possible or not.
https://www.tandfonline.com/doi/abs/10.1...15.1035467

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https://www.hatchmag.com/articles/tiger-...7024000000

Thanks for the links. Good info

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As an aspiring biologist, using sterile species makes sense to me from a management perspective. The population is easily controlled and so we can determine biomass goals, etc. 

But as an angler, it makes me . We have to continually dump money into fisheries if we want triploid rainbows or sterile hybrids. It feels lazy. What I most of all hate is to see fisheries that essentially self sustain replaced by tiger trout. We put tiger trout everywhere! Let's put that same energy and money into maintaining quality populations of fertile fish especially brook trout. I want diversity in our recreational fisheries. The DWR, for instance, will not manage northern pike even though many many states have no problem managing excellent northern pike fisheries that require no stocking. Think of Navajo Lake that is filled with chubs, if pike were added things could change. But the DWR wants to use tiger musky that are costly to grow, will not self sustain, and are extremely difficult to catch, instead. Everything else dies in there each winter, so maybe let's try an Arctic species??

Now, I don't think there is always a solid, simple solution when managing fisheries, but I do believe there is more wiggle room than the DWR is willing to admit when they think of what predator fish people want. I have a big list of fish I'd love introduced to Utah if I had my pick (flathead catfish as carp control anyone?) but I recognize that is unrealistic! I think Utah really needs to get the Colorado squawfish/pikeminnow to be used as a sportfish like they have the round tail chub. It would be an amazing predator and a native! I enjoy our fisheries in Utah but an emphasis on the same few species and put and take waters always disappoints me. 

There's my ramblings on Utah fish, it probably shouldn't be taken too seriously but I love our fisheries dearly and hope they can always improve.

I appreciate your thoughts. I would love some more options to chase quality northern pike. And flatheads would be a hoot. I dont agree with every decision made on this topic but I applaud the DWR for working hard to give us fishing opportunities. We are blessed with a lot of them for one of the driest states in the union and they deserve credit for working hard to help provide a mix of community ponds for kids and families to trophy water and primitive locations. I for one never complain when a smallmouth takes off with my trout rig.

[wormandbobber]

But as an angler, it makes me . We have to continually dump money into fisheries if we want triploid rainbows or sterile hybrids. It feels lazy. What I most of all hate is to see fisheries that essentially self sustain replaced by tiger trout. We put tiger trout everywhere! Let's put that same energy and money into maintaining quality populations of fertile fish especially brook trout. 

I get this frustration...but, honestly, what solution or other options are there with brook trout? If you leave them to self-sustain, you have a poor fishery that is underutilized. Poisoning is becoming more and more difficult because of the public...I really applaud the idea of trying something like this that is less costly. But, I would much rather have a quality fishery with healthy fish than a self-sustaining population of dinky brook trout that are starving. The thing that many people do not understand is that the very best brook trout lakes in Utah have ZERO reproduction and that is why they are quality lakes...they are completely maintained by stocking. The other lakes on Boulder Mountain, for example, that do produce quality brook trout only get some reproduction and go through cycles when fish are small and overpopulated. Oak Creek Reservoir is a good example of this...currently, it is putting out some really nice brook trout. But, a couple years of reproduction and the quality crashes (that is also why the legal limits of brook trout there are so high).

Remember, fishery managers only have 4 tools at their disposal to improve or manage fisheries: 1) fishing rules and regulations 2) public relations and education 3) fish stocking and fish removlal and 4) habitat improvement or manipulation. Of these 4 tools, which could be used to improve a stunted fishery and how? Looking at them, virtually all are in place when working with these poor self-sustaining fisheries.

R

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  4-step method to manage for quality fishing copy.pdf (Size: 1.26 MB / Downloads: 0)