Colonization and development of stream communities across a 200-year gradient in Glacier Bay National Park, Alaska

Canadian Journal of Fisheries and Aquatic Sciences
By: , and 

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Abstract

In May 1997, physical and biological variables were studied in 16 streams of different ages and contrasting stages of development following glacial recession in Glacier Bay National Park, southeast Alaska. The number of microcrustacean and macroinvertebrate taxa and juvenile fish abundance and diversity were significantly greater in older streams. Microcrustacean diversity was related to the amount of instream wood and percent pool habitat, while the number of macroinvertebrate taxa was related to bed stability, amount of instream wood, and percent pool habitat. The percent contribution of Ephemeroptera to stream benthic communities increased significantly with stream age and the amount of coarse benthic organic matter. Juvenile Dolly Varden (Salvelinus malma) were dominant in the younger streams, but juvenile coho salmon (Oncorhynchus kisutch) abundance was greater in older streams associated with increased pool habitat. Upstream lakes significantly influenced channel stability, percent Chironomidae, total macroinvertebrate and meiofaunal abundance, and percent fish cover. Stable isotope analyses indicated nitrogen enrichment from marine sources in macroinvertebrates and juvenile fish in older streams with established salmon runs. The findings are encapsulated in a conceptual summary of stream development that proposes stream assemblages to be determined by direct interactions with the terrestrial, marine, and lake ecosystems.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Colonization and development of stream communities across a 200-year gradient in Glacier Bay National Park, Alaska
Series title Canadian Journal of Fisheries and Aquatic Sciences
DOI 10.1139/f00-212
Volume 57
Issue 11
Year Published 2000
Language English
Publisher NRC Research Press
Contributing office(s) Alaska Science Center
Description 17 p.
First page 2319
Last page 2335
Country United States
State Alaska
Other Geospatial Glacier Bay National Park