THE FISH HAWK

The study of the Brown Trout fishery is now in it's fourth year. With the last few years being rather interesting, in terms of water requirements and usage on the 'Hooch, the information that is being collected for the study has been excellent.

A minimum flow program was an idea that Chris Martin with The State Fisheries division of the DNR wanted to implement as soon as the stocking of Brown Trout was stopped. He wanted to see how this effected the survival of any river born Brown Trout. Because so many water use issues were tied to the Chattahoochee, the minimum/consistent flows could not be done right away. Now they are trying to stick to the program. The latest results are rather telling. This data is based on sampling fish populations from the same areas: downstream of Bowmans Island, Fulton County side of Jones Bridge, and Roswell Shoals off of Riverside Drive. In 2006 (which was a wet year) they electrofished 64 trout per hour. In 2007 (1st drought year) the numbers were 224 trout per hour. This spring, 2008 (2nd drought year and the reduced, consistent flow implemented) the levels were 406 trout per hour! This information is based on "catch per unit effort" using a standard method of comparing catch rates between sites, years and resources.

What the data confirms is that low consistent flows have provided an excellent habitat for stream born Brown Trout. Lower flows have protected the banks of the River from the scouring effects of heavy releases from Buford Dam. The growth of aquatic plants and algae, as well as plant growth on the eroded banks, have not only provided protection for the fry, but has also allowed for a significant amount of bug life to be available as a food source for the the young trout. The interesting thing about the timing of this study is that if we had a full lake and a wet year, the minimum flow could not be done.

The minimum flows of the river are based on 650 cubic feet per second (cfs). The actual flow is 750 cfs to allow for the city of Atlanta to draw off water and also return treated waste water to the river system. These flows have to be approved through a meeting of various State and Federal Agencies as well as interested parties in Alabama and Florida. Future meetings could result in a change in flows from Buford Dam as rainfall, power generation and water needs change throughout the year.

The one catch with restricting flows during drought conditions causes the water to warm faster over less river miles due to solar radiation. Chris Martin has recorded 2-5 degree Celsius increase in water temperature at Island Ford this spring. This will make these areas marginal for trout habitat from July to September. To combat this, small release pulses are being sent down river to help cool the water.

What does all this mean to fishermen? The DNR has heard complaints from fishermen that "because of the absence of stocked Brown Trout they are not catching as many Browns as they used to." Chris is quick to point out that the River has plenty of trout in it. Since all of the Rainbow Trout are stocked, they are not as smart as, say, a "Wild" Brown Trout. The 'Hooch has an estimated trout population of 160,000! If the "recruitment" rate of river born Brown Trout increase at the current pace, Chris estimates that the Brown Trout population will be at levels equal to those while they were stocked. Fishermen who want to catch Browns are just going to have learn to be better fishermen.

Why are Brown Trout able to reproduce while Rainbows can't? It all has to do with water levels during the timing of the spawns. Brown Trout spawn in the fall when water levels are lower. The Brown Trout eggs do not get washed away or smothered.   Rainbows spawn some time between January and March, generally a time of higher releases from Buford Dam. Nature does find a way and some Rainbow Trout eggs do hatch, but it is in insignificant amounts.

After talking to Chris Martin, I felt really good about the future of our local fishery. We are lucky to have it. We are lucky to have guys at the DNR who are taking an interest in the Chattahoochee. With all the cuts in funding and staff at such state agencies as the DNR, it is good to know that quality people are making a difference in promoting and protecting the States natural resources.

                                                            -Rob Rooks