Riparian communities form through a succession of colonizers.

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"But for the longest successional sequences we have to turn to Milner's work in Glacier Bay National Park in Alaska, which overall covers five streams up to 150 years old (Milner, 1994). As glaciers melt, so streams appear and new habitat is constantly being created as the ice retreats. One particularly detailed study was based on Wolf Point Creek, which was created in 1965. In 1978, the community at one site was based on six species of chironomids associated with filamentous algae (Fig. 8.3). Mayfly and stonefly species colonized between 1984 and 1986, and blackflies and caddis a few years later. Predatory stoneflies first appeared in 1988 and increased significantly by 1990. The chironomids themselves showed marked changes with the initial colonizers (like Diamesa spp.) disappearing, and other taxa (like Pagastia spp.) replacing them. Although there was a gradual increase in water temperature over this period, the evidence pointed clearly to competitive replacement. Fish (Dolly Varden Charr) appeared around 1988 (Fig. 8.3). This is typically the first salmonid to colonize new stream habitats. Around 1000 pink salmon spawned at the site in 1991. Over the 30 years since the formation of the stream site, no non-insect invertebrate groups had established, presumably due to geographical barriers to dispersal. The insects have the advantage of flight as adults and hence aerial colonization of the new habitat." (Giller and Malmqvist 1998:199)

Journal article
Macroinvertebrate community succession in Wolf Point Creek, Glacier Bay National Park, AlaskaFreshwater BiologyMarch 11, 2003
E. A. Flory, A. M. Milner

The Biology of Streams and RiversOxford University Press, USAGiller, P. S.; Malmqvist, B.

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Journal article
Colonization and succession of invertebrate communities in a new stream in Glacier Bay National Park, AlaskaMilner, AM

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