Operational Plan for the Restoration of Diadromous Fishes to the ...

BKT total N N
0 50 100 150
1993
1994
1995
1996
1997
1998
1999
Pike presence
2000
year
Figure 6. Total abundance of brook trout for Rome Trout Brook, 1993-2007.
One pike
found in monitoring site in 1998, 2001, and 2002. 2001 and 2002 were drought
years.
Brook trout abundance in Rome Trout Brook varies annually with the lowest
abundance in 2001 and 2002 (Figure 6). The lowest numbers of brook trout young
of the year also occurred in 2001 and 2002 (Figure 5). Pike presence within this
stream is not common with only 3 total pike being detected; one each in year 1998,
2001 and 2002. It is difficult to determine if the greatly reduced brook trout indices
for 2001 and 2002 are the result of pike presence at the time of the survey or if low
flow and drought conditions exacerbated the effect (Figure 3). However, in the only
year that pike were present and water conditions were normal, brook trout
abundance and YOY abundance were within the range of annual variation in years
that pike were absent. Those years also show the lowest overall relative fish species
diversity and abundance that are indicative of drought stress. It is possible that pike
intrusion 1.5 km upstream from their source lake is not a common occurrence and is
precipitated by environmental stress that forces some individuals to take extreme
chances in unusual conditions.
Baker Branch of the St John River: Muskellunge (Esox masquinongy) are an Esocid
fish similar in morphology and ecology to northern pike. Muskellunge occur in
Maine’s St. John River system presumably as a result of legal stocking events in
Quebec’s Lac Frontiere in the late 1960s. Although muskellunge tend to move
much greater distances than other esocids and tend to prefer large river habitats
over truly lentic areas whereas pike tend to be the opposite, the fish community
effects and habitat relationships caused by muskellunge are similar to the ecology of
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2001
2002
2003
2004
BKT
2006
2007