Acadia National Park - FLOW: Freshwater Fish

The management and protection of native fish species and aquatic communities, while providing the recreational angler with a quality fishing experience, is the focus of the National Park Service"s recreational fisheries program. The NPS together with the Maine Department of Inland Fisheries and Wildlife regulate and manage freshwater fishing in Acadia National Park.

The fish communities of ponds and brooks of Mount Desert Island, particularly those within the boundaries of Acadia National Park, have been influenced by humans for well over a century. Angling pressure has increased substancially, especially in the second half of the twentieth century. This has resulted in extensive stocking of fish species native to Mount Desert Island as well as non-native and exotic (e.g. brown trout) introductions.

Virtually all ponds have been influenced by stocking at some point during the century. Of 24 ponds, only 4 have not been stocked, and these are all under 16 acres in size. The first intentionally introduced species was smallmouth bass in 1891. Since that time, brook trout, rainbow trout, brown trout, Sunapee char, lake trout, landlocked salmon, alewives, rainbow smelt, largemouth bass, steelhead, sea-run Atlantic salmon, and various species of sticklebacks and cyprinids have all been stocked in waters within Acadia National Park. As a consequence of these community species alterations, 91% of the ponds that contain fish no longer contain their original species mix.

Historically, 30 species or subspecies of fishes (see list below) have been confirmed for waters within the Park, but only 14 of these are native to MDI. The most widespread of these native fishes are banded killifish and golden shiner, each found in 79% of the ponds, as well as in several brooks. Other widely distributed fish species within Park waters are brook trout (71% of ponds), pumpkinseed (67%), American eel (63%), white sucker (54%), and northern redbelly dace and rainbow smelt (each 50%).

As a general trend, there is less multi-species stocking in the 1990s compared to even two decades ago. Most recent stocking has been with salmonid fishes. Numbers stocked have declined, but the size of stocked fish is larger, to promote higher survival. Only Bear Brook Pond, Duck Pond, and Lakewood have presumably never been stocked. Thus, if natural fish communities are to be studied, these three small ponds probably reflect the original fish communities.

Since almost all waters within the Park are biologically altered from their original species mixture, most fish communities will never return to their original state, especially with high angler demands of salmonids from local residents and tourists. Stocking has been a tool for meeting this demand - to introduce new species of game fish or to supplement existing populations. Logical research directions for the future could address the biogeographical progresssion of community changes and the consequences of such species changes.