Montague Island Riparian Rehabilitation (Restoration Project 97139C1). EXXON211 VALDEZ Oil Spill Restoration Project Final Report

摘要

From 1994 to 1996, riparian restoration work was undertaken in four watersheds on211u001eMontague Island where logging had occurred in the 1960's and 1970's. Although 211u001ethis work would not deal directly with the habitat oiled by the Exxon Valdez oil 211u001espill, it was felt that the restoration of these watersheds would improve 211u001econditions throughout the stream systems and contribute to the overall 211u001erestoration of chum salmon (Oncorhynchus keta) and pink salmon (O. gorbuscha) in 211u001ePrince William Sound. The work involved two major parts: building instream 211u001estructures to reduce erosion, moderate flows, and improve fish habitat; and 211u001ethinning crowded riparian vegetation to stimulate the growth of Sitka spruce, 211u001ewhich was the dominant species before the logging. Most of the structures 211u001edesigned to create habitat were successful, but those built to reduce velocities 211u001ein the main channel of Hanning Creek either washed out or had limited effects. 211u001eWhile the habitat structures provide rearing area for Dolly Varden (Salvelinus 211u001emalma), the main channel structures have had no apparent benefit for the targeted 211u001esalmon species. Mainstem and whorl growth of trees in thinnned areas was 211u001esignificantly greater than growth in untreated areas. Thinning should accelerate 211u001ethe production of large diameter trees which will become the source of large 211u001ewoody material for the streams in the future.