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

MAINE DEPARTMENT OF MARINE RESOURCES
BANGOR, MAINE
NORTHERN PIKE MOVEMENT BARRIER RISK ASSESSMENT SURVEY
1.0 INTRODUCTION
In recent years non-indigenous fish species have become widespread throughout Maine,
in some cases by deliberate introductions, and in other cases due to colonization from an
expanding local population. In some cases, there have been documented impacts to native
species, such as brook trout, and other non-game species resulting from these invasions (Boucher
and Bonney, 2004; Gallagher, 2004).
Northern pike (Esox lucius) were illegally introduced into the Belgrade Chain of Lakes in
the 1970s, and are now present in the Kennebec, Androscoggin, and coastal river drainages
(Maine DIFW, http://www.maine.gov/ifw/fishing/illegal_stocking.htm). In the Penobscot
watershed, a northern pike population is established in Pushaw Lake, a tributary lake near
Bangor.
Northern pike are believed to be presently confined to the Pushaw Stream subwatershed
in the Penobscot drainage. Routine fishery monitoring and also recent electrofishing surveys of
Pushaw Stream and the Penobscot River have not detected northern pike at other locations
(Yoder, et al. 2005; Kleinschmidt Associates, 2009). However, there is no barrier preventing
volitional access from the Pushaw drainage to the mainstem Penobscot River. Should the
species ever become established in the Piscataquis River drainage, two tributary streams with
headwaters in a breached divide between the Piscataquis and West Branch Penobscot drainages
potentially could serve as a thoroughfare allowing northern pike to invade the West Branch. The
two sites of interest are: Wangan Brook (southern-flowing inlet to Upper Ebemee Lake) in
Piscataquis County and East Branch Lake which connects the East Branch Seboies Stream to
Nollesemic Lake in Penobscot County.
The goal of this survey is to provide an analysis of the potential for these two streams to
provide access to the West Branch for northern pike, based on surveyed stream channel
conditions.
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