Trout

LAKE TROUT OF BOL
Unique to the upper Mississippi River Basin and may constitute the only pure-ancestry remnants of the Pleistocene Mississippian Refugial Race of lake trout. BOL IS ONE OF TWO LAKES IN THE STATE OF WISCONSIN with NATIVE LAKE TROUT AND IS THE ONLY LAKE WITH ENTIRELY NATURAL REPRODUCTION SUSTAINED. This trout is genetically unique to BOL. Trout Lake and BOL strains are pure strains and very different from each other. The Wisconsin DNR determined that preservation of this unique trout should be a priority of BOL . Secondary lakes used to preserve trout are Big Carr, Oneida County Long, Vilas Lucerne, Forest Keyes, Florence Lac du lune, Vilas All of these lakes contained smelt.

BOL netting by the WDNR is limited to 3 nights with nets being run the same night and not set overnight to reduce mortality. Additional netting will only be conducted to obtain the minimum number of eggs needed to produce the yearlings. Four fish have been implanted with receivers done in October 2001 which should have worked til 2002 and some til 2003. Receiver lakes are monitored for temperature oxygen profiles. Habitat temperature values need to be 15.5 deg C. Upper boundary in water column. Determine water depth for useable habitat 10.0 deg C. Upper limit boundary, upper limit of preferred zone for adults Dissolved oxygen parameters Determine 6, 4, and 2 ppm oxygen reading will overlap with 10 deg C or less for adults preference. 4ppm is lower limit preference for juveniles. 2 ppm oxygen determines limit of tolerable zone. In 2003 bag limits we changed from 26″ minimum of ONE fish, protecting 75% of adult population to 30″ and one fish protecting 90% of adult population. Uniform to Trout Lake regulations. Other alternative was to close trout harvest. Stocking is detrimental for this trout and could result of eliminating recruitment of naturally produced juveniles. If population of trout declines, walleye would no longer be stocked. Trout that would be stocked, if necessary, would not be a different genetic make-up. Angler harvest repercussions are always monitored when testing is done by the WDNR. 6 year old trout (determined by scale samples which are fairly reliable for 6-8 year olds, but fin clips are more reliable) varied from 18.7 to 25 inches total length. Sex of females to male ranges 2.2 to 1 and 4.0 to 1. Females do not spend as much time at spawning cites as males do. Trout from Trout Lakes are generally longer in length than those from BOL by 1 to 3 inches from 2001 and 2002 nettings. Lake Trout management is guided by Upper Wisconsin Basin Inland Lake Trout Management Plan and is usually sampling every 5 years , but may be repeated at shorter intervals if deemed necessary. They monitor population, density, size structure and growth rates of lake trout and determine testing needs to be done in a few as 2 year intervals or slightly longer times. If walleye become detrimental to the trout population, stocking of them would be discontinued. Large or increased harvest of our trout, competition with walleyes, and low recruitment of juveniles may result in the loss of this genetically unique fishery. This information was obtained from the Black Oak Lake Watershed Protection Program book of 2005, loaned to me by Jean Cuttell. Thanks to all our prior and present members who work so closely with the WDNR for the preservation and health of our lake. This is a very extensive and complicated program. It involves hours of time and depth of knowledge that is amazing.  

Read these articles for some additional information about our Lake Trout.

Black Oak Lake Trout Study

Black Oak Lake Trout Summary