Cayuga Lake’s Lake Trout Population – How big is it?


One thing I’ve often wondered is, “how large is the population of lake trout on Cayuga or Seneca Lakes?  DEC hasn’t done any population estimates on these lakes in decades, but I did come across some older information which may be enlightening.  Dan Bishop’s Master Thesis, published in January 1996 gives us a few clues.  The paper that I have a copy of is entitled “EVALUATION OF THE EXPERIMENTAL SEA LAMPREY CONTROL PROGRAM IN CAYUGA LAKE, NEW YORK FINAL REPORT.”

Chart of Lake trout population estimates through the 1980s - by Kosowski, Engstrom-Heg

We can see here that the lake trout population on Cayuga Lake fluctuated from lows of 6,000 in 1981 and 1982, to highs of around 20,000 adults in 1989.  Anecdotally, I believe that the population on Cayuga Lake hit even greater highs in the mid-1990s, so it may have gone up to 25,000 or more adult fish.  Seneca Lake ranged from lows of 6,000 to 7,000 adult lake trout in 1980 (when lake trout fishing there was awful), up to highs again around 23,000 adults in 1987, before it tapered back down again.  I would guess that the Seneca Lake lake trout population went up again in the late-1990s due to wild production.  It tapered down sharply after the 2011/2012 lamprey population highs.

Indicators now suggest that the Cayuga Lake lake trout population is very abundant, so I would guess that we are somewhere around 20,000 to perhaps 25,000 adults.  That’s about one adult lake trout per every 2 acres of lake.

During the course of the year, I think more fish are being harvested now – from late-March through April and into May than at any other point during the year.  The population needs to be brought down somewhat and given the numbers of anglers targeting lake trout now, we may see that happen.  The lake will be gill-netted by the DEC this summer, so we should have some idea of how abundant the lake trout population is by then.

The bottom-line is that, if you think Cayuga Lake is currently loaded with lake trout, you are correct!