04-09-2018, 03:44 PM
Keep in mind that back when those surveys conducted it was legal to keep all those foul hooked fish. That really increased the number of fish that could be legally harvested. While we haven't creeled the inlet since it's reopening, there is likely considerably less legal harvest now than back in the 60's and 70's.
Fishery biologists rarely conduct population estimates on reservoir fisheries so I don't have a population estimate for walleye on the reservoir. The reason actual population estimates are rarely done is that they involve mark and recapture, which requires collecting and marking a large number of fish and then following up on multiple occasions to collect those fish. In addition, by the time we have the actual estimate, it is assumed that the population will have changed by then. So basically there has to be a strong question for us to conduct a population estimate on a reservoir population of fish. Instead of population estimates we track populations in reservoirs through "relative abundance", which is a measure of how many fish of the species of interest we see in our trend netting catch from year to year. Basically, what we do is run a calculation on how many nets we have to set to detect a real change in the population. If we set too few nets, any changes we see might just be due to random chance or getting lucky by hitting a school of fish. If we set too many nets, than we are wasting time that we could be using sampling other waters. Basically, we look for the sweet spot of how many nets we need to actually track the population with confidence. With this in mind, if the numbers we see in our nets go up, it is assumed the population has gone up and if the numbers we see in our nets go down, it is assumed the population has gone down. Using this concept of relative abundance allows us to keep track of many fisheries in one year, where if we tried to do population estimates we would probably limit our knowledge and sampling ability to just a few waters. We definitely need the ability to keep tabs on multiple waters in a year as my office alone is responsible for overseeing Rockport, Echo, Pineview, Mantua, Willard, East Canyon, Lost Creek, Hyrum, Bear Lake, Newton, part of the Uintas, the Weber River, Logan River, Blacksmith Fork, and more.
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Fishery biologists rarely conduct population estimates on reservoir fisheries so I don't have a population estimate for walleye on the reservoir. The reason actual population estimates are rarely done is that they involve mark and recapture, which requires collecting and marking a large number of fish and then following up on multiple occasions to collect those fish. In addition, by the time we have the actual estimate, it is assumed that the population will have changed by then. So basically there has to be a strong question for us to conduct a population estimate on a reservoir population of fish. Instead of population estimates we track populations in reservoirs through "relative abundance", which is a measure of how many fish of the species of interest we see in our trend netting catch from year to year. Basically, what we do is run a calculation on how many nets we have to set to detect a real change in the population. If we set too few nets, any changes we see might just be due to random chance or getting lucky by hitting a school of fish. If we set too many nets, than we are wasting time that we could be using sampling other waters. Basically, we look for the sweet spot of how many nets we need to actually track the population with confidence. With this in mind, if the numbers we see in our nets go up, it is assumed the population has gone up and if the numbers we see in our nets go down, it is assumed the population has gone down. Using this concept of relative abundance allows us to keep track of many fisheries in one year, where if we tried to do population estimates we would probably limit our knowledge and sampling ability to just a few waters. We definitely need the ability to keep tabs on multiple waters in a year as my office alone is responsible for overseeing Rockport, Echo, Pineview, Mantua, Willard, East Canyon, Lost Creek, Hyrum, Bear Lake, Newton, part of the Uintas, the Weber River, Logan River, Blacksmith Fork, and more.
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