Monthly Archives: October 2013

Data on 2013 Radiotracked Brook Trout Are Now Online

I am finally caught up with entering the radiotracking data we collected this spring and summer into our online map. Last year we tagged and tracked 11 immature (6” or less) brook trout. Starting in April of this year we have tagged and tracked an additional 16 immature brook trout and 5 mature (8” or greater) brook trout. We will be releasing an additional 6 immature trout in the next week.

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Here are some highlights of the data collected thus far (to view specific fish just click on one of the two links and make sure the only the box for at particular fish or fishes is checked):

  • 7 trout were not located after release.
  • A large majority of the tags were discovered detached from a trout. We have strong evidence that at least in some cases this was caused by predation (see for example 27).
  • Both immature and large trout showed the greatest movement right after release.
  • However larger trout moved more and all four of the large trout which we were able to track after release entered Beaver Lake. None of the immature trout moved that far downstream.
  • One of the large trout (101) returned upstream after entering Beaver Lake and remained for several months well upstream in Beaver Lake. The other three disappeared in the lake as summer temperatures rose into the upper 70’s.
  • Patterns of movement among immature trout varied considerably but can be divided into two two general types:
    • Movers. Examples include 20, 23, 25, 22b
    • Stayers. Examples include 17, 18, 19, 24, 21b, 28

LITU’s Radiotagged Trout – Final Results

Tracking of the five mature brook trout we released in Beaver Brook this past spring and summer is done. Of the five fish we released, one (104) disappeared right after release. That probably means it was eaten. The other four moved downstream and entered Beaver Lake. One trout made it to the entrance of Beaver Lake three days after release, at which point it did not move again. Either the trout was eaten or it dropped its tag. Two others moved deep into the lake and never returned to Beaver Brook. Both of them appeared to have stopped moving this summer. I suspect conditions were lethally hot by that time (temperatures were well over 78 by late June). Finally, 101, released in early April, traveled all the way to the Beaver Lake spillway within one week of release and then returned to Beaver Lake the same day. It spent the next three months in a 200 yard upstream stretch above the concrete bridge before the tracking signal was lost in mid July. Here is the map of their movements:

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