Priority No. 1: Prevent spread of northern pike

Posted Feb. 26, 2009, at 9:04 p.m.

There are serious concerns over the Penobscot River Restoration Trust’s proposal to allow unrestricted fish passage into the Piscataquis River through a bypass channel around the Howland dam. Specifically, this proposal will result in some unintended and very undesirable consequences. These have not been widely aired in the PRRT’s public relations blitz over their Penobscot project.

Northern pike are present in Pushaw Lake and the Pushaw Stream drainage. Despite ongoing efforts to suppress the population there, and despite the fact that they have not yet been confirmed in the main stem of the Penobscot River, pike can move into the Penobscot, and they can move upstream to Howland and Enfield where fortunately they are now stopped by dams.

With PRRT’s proposed bypass channel around the Howland dam, northern pike will have access to approximately 40 percent of the Piscataquis River drainage, assuming they are stopped by dams in Milo on the Sebec River and in Dover-Foxcroft on the main stem of the Piscataquis River. Therefore they can invade 25-plus miles of main stem river, 27-plus miles of the Pleasant River, including its east and west branches, the Seboeis Stream drainage, and many small tributaries. These all provide wild brook trout habitat and Atlantic salmon habitat essential to the success of the Penobscot Restoration Project.

Northern pike are very efficient predators. They live in rivers and streams as well as in lakes and ponds. From the time they are only 2 inches long their diet consists primarily of fish. We can expect that both salmon and brook trout will be included in their diet as pike expand their range in the Penobscot and Piscataquis drainages.

There are many references to the adverse impact of pike when they have been introduced over existing salmonid populations in North America. There is even more convincing evidence from waters in Maine’s Belgrade Lakes region. What will be the consequences of pike on Atlantic salmon restoration in the Piscataquis drainage? What will be the consequences on wild brook trout?

The ongoing multiagency group effort to assess the risk of pike spreading farther once they enter the Piscataquis drainage in Howland is an exercise in planning a secondary line of defense. Although it is essential to preclude pike from extending farther into the Piscataquis drainage and to preclude the possibility that pike might also find their way from the Piscataquis River drainage into the Penobscot River’s West Branch, the first line of defense should be to prevent northern pike from entering the Piscataquis River in Howland.

With the interest and state and federal policies aimed at stopping the spread of invasive species such as the northern pike, it seems only common sense to consider an alternative to the bypass channel proposed at Howland. The Howland Dam should be maintained as a barrier to upstream fish passage. A fish trap, lift and sorting facility should be constructed in it that would allow the removal of undesirable invasive species.

Certainly, all provisions for upstream fish passage through dams on the Penobscot River and its tributaries should be designed to preclude the movement of any invasive species. This is present policy for upstream fish passage in the Kennebec River drainage. Shouldn’t it apply to the Penobscot River?

Desirable anadromous species targeted for restoration can be passed upstream through a sorting facility at the Howland Dam. Although a fish trap and lift may not be 100 percent efficient at passing some species upstream and does not meet the criteria of safe, timely and effective fish passage acceptable to restoration interests, given the potential adverse impact when pike enter the Piscataquis River drainage, is not this a reasonable alternative to allowing free passage of northern pike through Howland?

A lift and sorting facility in Howland has an added advantage of providing the opportunity to count what is moving upstream. Isn’t that a good way to assess the success of restoration as time progresses? This is an alternative that should be on the table for consideration. The public now needs to be included in the discussion regarding the risks associated with restoring the Penobscot under the present proposals as well as the benefits.

We are living with the scourge of illegal, irreversible fish introductions throughout Maine. Their effects are forever. However, the threat of illegal introductions should not be a reason to rationalize allowing pike to expand their range in the Penobscot Restoration Project. When an alternative exists to prevent them, the unintended consequences of allowing northern pike to increase their distribution in Maine in the Piscataquis drainage, sanctioned by the state and federal government and private nongovernmental organizations, is ecologically irresponsible, contrary to public policies and, most importantly, unacceptable.

Paul Johnson of Oakland is a retired Moosehead Lake Region fishery biologist who managed the fisheries resources in the Piscataquis River drainage.

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