Numbers could be slightly up in N. Channel, but news not good in lake overall
MANITOULIN—Fisherpeople equipped with flashlights, waders and dip nets could be spotted in large numbers in Kagawong last week as the annual smelt fish was underway.
Many reported high numbers of smelt and also commented on the size, with many adult smelt found in the nets.
The Expositor spoke with Arunas Liskauskas, management biologist for the Upper Great Lake Management Unit with the Ministry of Natural Resources and Forestry (MNRF), about what this means for Lake Huron and if smelt are on the rise.
“The information we have (on rainbow smelt) is rather limited and based on the annual United States Geological Survey (USGS),” explained Mr. Liskauskas. “They use hydroacoustics to look at the prey fish in Lake Huron.”
The USGS vessel Sturgeon can be found each fall in Little Current during its annual survey.
“In general the information is telling us that there have been changes since the collapse of the alewives in 2003 which was due to an increase of quagga mussel,” Mr. Liskauskas continued. “Quagga mussels remove a lot of nutrients which produce plankton which has had major implications for rainbow smelt as well.”
The USGS divides Lake Huron into three basins: the main basin of Lake Huron, Georgian Bay and the North Channel.
Last year in the 2014 survey, the technicians saw a slight increase in rainbow smelt aged one year and older, per hectare in the lake, but the survey detected a two-fold increase in smelt in 2014 over the previous year in the North Channel.
“It is a fairly complex story, for 2015 smelt are down in the lake generally, but up slightly in the North Channel,” said Mr. Liskauskas. “It was also noted that most of the smelt were small, but they were a bit larger in the North Channel.”
“In general, prey fish (such as rainbow smelt) are well below the averages of the 1980s and ‘90s,” he added. “In the North Channel smelt may be up compared to the rest of the lake, but its also still below the ‘80s and ‘90s.”
Mr. Liskauskas said that Lake Huron’s ecosystem is changing due to invasive species such as the quagga mussels and the round goby and that these changes will not likely benefit species like rainbow smelt.