Open AccessEvaluating Changes in Diadromous Species Distributions and Habitat Accessibility following the Penobscot River Restoration Project
Author(s) -
Trinko Lake Tara R.,
Ravana Kyle R.,
Saunders Rory
Publication year - 2012
Publication title -
marine and coastal fisheries
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.664
H-Index - 28
ISSN - 1942-5120
DOI - 10.1080/19425120.2012.675971
Subject(s) - fish migration , habitat , fishery , acipenser , range (aeronautics) , population , drainage basin , alosa , restoration ecology , geography , sturgeon , ecology , environmental science , fish <actinopterygii> , biology , materials science , demography , cartography , sociology , composite material
The Penobscot River basin, covering approximately 22,265 km 2 , is the largest river wholly within Maine and the second largest river system in New England. The Penobscot River Restoration Project (PRRP) is a multimillion‐dollar endeavor that aims to restore native sea‐run fish through the removal of two main‐stem dams and improved fish passage at a third dam on the Penobscot River. We used geographical information systems, accounts of historic ranges, and barrier survey data to estimate species‐specific distributions and habitat accessibility for 11 diadromous species before and after the proposed restoration. We predict a range of outcomes in terms of expected distribution and accessibility that are largely based on habitat use and life history differences. For 4 out of 11 species (Atlantic sturgeon Acipenser oxyrinchus , shortnose sturgeon A. brevirostrum , Atlantic tomcod Microgadus tomcod , and striped bass Morone saxatillis ), the PRRP is anticipated to provide access to 100% of their historic freshwater habitat. However, for alewives Alosa pseudoharengus , approximately 69% of the historic spawning and rearing habitat will remain inaccessible due to the presence of other passage barriers. Our results demonstrate that the PRRP is an important step toward ecosystem recovery in the Penobscot River basin but that other restoration activities will be needed to realize the full potential of the PRRP, particularly for alosines. Further, our results provide the first spatial analysis of diadromous fish distribution and access following the PRRP and serve as the baseline for developing a guiding image for expected diadromous fish population responses following the dam removals. Received March 21, 2011; accepted August 21, 2011