Northern Wyoming News - Serving the Big Horn Basin for over 100 years

BASIN - The Wyoming Game and Fish Department, along with Colorado State University research student Dan Cammack, completed their collection of sauger eggs from the Big Horn River in Basin on May 23-25.

The collection is the beginnings of a study that looks to determine how temperatures affect sauger in their early stages of life.

"The egg take itself went really, really well," said Wyoming Game and Fish Cody Region Fisheries Supervisor Sam Hochhalter. "This was the big field effort to start the experiment. Twenty thousand eggs was the goal and we went over that Thursday morning. The eggs from seven females made the trip to Colorado State University just fine and everything seemed to be going smoothly in the lab."

The study will help the WGF better understand how water temperature fluctuations, either due to greater runoff or drought, will impact the sauger recruitment.

"For us down low in the Big Horn system we see, and have for a long time, seen a consistent recruitment in the Big Horn sauger population. They'll go two or three years without a good recruitment event but never longer. But a place where we see recruitment getting to a point that concerns us is up in the Wind River drainage.

"They'll go five or six years without a good recruitment. We have intervened by stocking sauger up there and this is trying to get us information to better be able to determine when that could be needed," said Hochhalter.

The sauger group was able to collect male and female sauger by means of electrofishing; then sorted through the best sauger, placing them in holding tanks until they were "ripe" and able to collect the eggs needed.

The study will have three phases, the first focusing on the eggs in various water temperatures.

"This is one phase of three. The first phase is looking at how different water temperatures affect hatching success. [Cammack] will have several different treatments, cold water all the way up to warm water. Then he'll have one that mimics the daily temperature swings we'll see in the Big Horn during drought years," said Hochhalter.

The second phase will determine how the eggs are affected by the temperature variations while still in the sauger female.

"The second phase is looking at how similar temperatures influence egg quality while still in the female," said Hochhalter. "Fish are cold-blooded and their body temperature is the same as the water they're living in. So we want to run females that are holding eggs through similar trials."

And the third will see if another egg collection is needed should the study produce results that call for it.

"Then we have the potential to do another egg take next year should we learn anything this year that we want to further expand upon," said Hochhalter.

Analysis of the data will be completed later this year and will hopefully allow for the WGF to better track the sauger population.

"We'll have a good idea in another month but it will probably be more likely this fall when we have some numbers to look at and we'll know what we learn from this first effort," said Hochhalter. "So rather than spending two weeks electrofishing, if we know where the water temperatures are at we can act accordingly. It makes us far more efficient in terms of how we keep our finger on the pulse of the populations and hopefully provide better information for when intervention is necessary."