Alewife populations and salmonid stocking numbers have been a scorching subject ever since back-to-back chilly winters in 2013 and 2014 prompted considerations of a doable prey inhabitants collapse.
Each April, scientists from Ontario’s Ministry of Pure Assets and Forestry (MNRF) and New
York’s Division of Environmental Conservation (NYDEC) full a bottom-trawl pattern of Lake
Ontario’s pelagic prey populations. They drag nets and accumulate acoustic knowledge at areas throughout the
lake. The info supplies a sign of the dimensions and age courses of alewife, and consequently, how
finest to handle predator species stocking.
To scale back the stress on depleted alewife populations, the MNRF and New York’s NYDEC made modifications to salmonid (lake trout and salmon) stocking, beginning in 2017 and 2018 with a 20% discount. In 2019 and 2020, a further 20% minimize in chinook stocking numbers was made, adopted by no additional reductions in 2021, and a ten% improve in 2022.
This previous spring, it was initially believed {that a} sturdy yr class of 2020 alewife would offer a big biomass improve in 2022 and 2023. Nonetheless, upon additional investigation, scientists discovered there was a higher-than-expected mortality of these two-year-old alewife, probably due to heavy predation from salmonids.
Though this isn’t as optimistic as as soon as thought, MNRF Lake Supervisor Andy Todd famous the MNRF would adapt to the brand new findings and mentioned: “We now have a rock-solid science program that’s monitoring lake-wide prey fish so we will work on options from an knowledgeable place.”
To learn the Nice Lake Fishery Fee’s 2022 report, click on right here
