Olga

Olga is a designated stream trout lake that has been managed for Brook Trout or Splake since 1971. Splake (1,000 fingerlings/stocking) have been stocked in this lake annually since 1994. This was the first of two surveys scheduled in the current (2014) lake management plan to determine whether goals for the Splake population have been met, and whether the lake continues to provide the cool, well-oxygenated waters needed by Splake and Brook Trout. Splake appeared to have been fairly abundant in 2016, although most were small. Goals for Splake in this lake were met in 2016, although not by a wide margin. The gill net catch exceeded 5.0 fish/set, at least two year classes of fish over 10 inches in length were present (actually four), and the capture of one fish larger than 16 inches met the goal of producing some fish of that size in this lake. Long-term survival of stocked fish appeared to have been good, with Splake as old as six years taken. Growth, however, had been slow. Fish reached a mean length of just 11.0 inches at the end of their third year, compared to an area average of 12.8 inches. Competition from White Sucker may have contributed to the slow Splake growth observed in 2016. White Sucker have been present in this lake since at least 1971, and the 2016 gill net catch was similar to past catches seen in Olga Lake. The 2016 gill net catch exceeded the normal range (2.83-14.83 fish/net) for surveys of stream trout lakes in this area, suggesting White Sucker abundance may have been excessive. Poor water quality may also have driven slow Splake growth. The temperature-oxygen profile measured on 17 August 2016 found conditions suitable for Splake (water temperature 5 ppm) in just a narrow range of depths (about 6.5 to 7.5 ft). As has often been observed in deeply bog-stained lakes like Olga, the transition from warm surface waters to colder deep waters was shallow and abrupt, with cold waters at depths greater than nine feet essentially lacking oxygen entirely. Although Olga Lake is over 40 ft deep, most of that water is unavailable to trout by the end of the summer.

This assessment was done to confirm results of a 2008 assessment that failed to find any trout in Olga Lake. The results of that assessment were suspect because the lake was reported to have supported some good fishing for splake the previous winter. Splake were found in 2009. The gill net catch fell short of the normal range (6.00 to 14.25 fish/set) for spring assessments of stream trout lakes in this area, but met the long range goal for the species (5.0 fish/gill net set) established in the 2005 lake management plan for Olga Lake. Splake growth had been about average for the area, two-year-old fish reached a mean length of 9.2 inches by the end of their second year and three-year-old fish reached a length of 12.2 inches. White sucker abundance appeared to have been high in 2009, although it still fell within the normal range (3.17 to 28.00 fish/gill net set) for catches in spring assessments of stream trout lakes in this area. White sucker compete with trout for invertebrate forage, and their presence in the numbers indicated by the 2009 assessment might result in reduced growth rates for stocked splake.

Although Olga Lake has been stocked with splake fingerlings annually since 1993, and despite good fishing reports in the winter of 2008, the June 2008 assessment failed to find any splake. This was the first assessment of this lake since stocking began (1971) to fail to catch a trout of some kind. It is likely that the failure to take any splake this time was a fluke, but to be sure, and to get information on the splake population that we failed to get in 2008, the assessment will be repeated in June 2009. White sucker have been present in Olga Lake since assessments began. The 2008 catch was one of the lower catches seen in this lake, and was below the normal range (3.2 to 28.0 fish/gill net set) for stream trout lakes in this area.

Based on Minnesota DNR survey data, anglers target Brook Trout and Splake in Olga. See the full species list above for catch rates, size structure, and quality scores.

Minnesota DNR records list public access for Olga. Check the DNR LakeFinder page for the launch type and directions before you go.

Olga has a maximum depth of 45 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Olga is from 2016. Surveys this old should be treated with some caution — fish populations change over time.

No invasive species are on record for Olga in Minnesota DNR data. Always clean, drain, and dry your equipment to help keep it that way.