What's Up with the Alewife?
Gap in Alewife Age Class Structure to Impact Lake Ontario Fishery
By David Rockwell & Garrett Brancy
- Little did we know that the brutal cold winters of 2014 and 2015 may have produced such lasting effects on Lake Ontario’s Trout and Salmon fishery.
These two extremely cold winters likely had a significant effect on the survival of alewife -specifically “young of the year” alewife. Experts speculate that the young alewife simply were not large enough to make it through the prolonged cold winter and subsequently perished (It’s important to note that Lake Ontario is located in the northern-most limit of the alewife’s range and they are not native to freshwater systems which get colder than marine environments). As a result, annual alewife population trawls conducted by the USGS have revealed that few young of the year alewife appeared to have survived the winters of 2014 or 2015. This has caused an apparent “gap” in the alewife age class structure in Lake Ontario. This gap will likely result in a significant decrease in the available forage base for chinook salmon and other sportfish for at least several years. In 2017, these two age classes of alewife would usually make up the primary forage base for chinook salmon which most often consume age 3, 4, and 5 year old alewife. These same fish also comprise the majority of the reproductive potential, which could impact the population’s ability to rebound to more typical levels.
To ensure the long term health of the Lake Ontario salmonid fishery the NYS DEC, in conjunction with the Ontario Ministry of Natural Resources, have made the decision to reduce overall stocking of chinook salmon and lake trout by 20% beginning in 2017. This stocking adjustment is a precautionary measure to ensure that sportfish have enough forage to support healthy populations. Basically, the adjustment will hopefully help prevent the chinooks from eating themselves out of house and home. Simply put, a potential collapse in the alewife population in Lake Ontario would likely result in the collapse of our salmonid fishery –specifically and most particularly the chinook salmon.
It’s noteworthy to mention that alewife population collapses have been well documented in both Lake Huron and Lake Michigan, in part due to over-stocking of sportfish. For Lake Huron, the alewife population collapsed in just 3-4 years and the chinook salmon fishery there has never recovered. In Lake Michigan, fishery managers are now considering an 80% reduction in overall salmonid stocking for 2017. This information is a strong indicator to the Lake Ontario fisheries managers that they have to take action now to prevent the over predation of the alewife in order to maintain a salmonid based sport fishery.
The good news:
- There is a plan and fisheries managers are acting quickly. The stocking adjustment will result in an estimated 228 million fewer alewife (7.5 million pounds) being consumed between years 2018-2020
- Once alewife populations recover, fisheries experts anticipate that king salmon and lake trout stocking can return to target levels
- Nearly 50% of the chinooks caught by anglers in the Lake Ontario watershed are naturally reproduced or “wild” fish, resulting in only a 10% effective reduction in chinook stocking
- No reduction to the stocking of any other salmonid species (coho, browns, steelhead, or Atlantic salmon)
- We’ve actually experienced greater chinook stocking shortfalls in the past due to inability to collect the target number of salmon eggs (drought related) with no noticeable impact on angling success
- The Salmon River will receive stocking preference over other rivers to ensure adequate numbers of returning adults to the DEC’s Salmon River Hatchery in Altmar.
Douglaston Salmon Run applauds the NYS DEC and OMNR for their quick analysis and action, all the while holding many public meetings to keep anglers informed and ask for their input.
Dave “Rocky” Rockwell (US Army ret.) is a Douglaston Salmon Run approved guide and member of Zero Limit Adventures Guide service. He is also works in conjunction with Douglas Outdoors and Tailwater Lodge in Altmar NY. Rocky enjoys spending most of his day’s streamside or making presentations to fishing groups.
Garrett Brancy is the General Manager of Douglaston Salmon Run in Pulaski NY. DSR is 2.5 miles of private waters on the famed Salmon River where access is limited and the angler’s experience is focused on sportsmanship, ethics, and conservation.