A Long-Term Evaluation of Trout Habitat Development and Its Relation to Improving Management-Related Research

Abstract

Responses of a wild brook trout (Salvelinus fontinalis) population to instream habitat development in a 0.7 km reach of Lawrence Creek were monitored for 7 years and compared to population data for the 3‐year period prior to development. Mean annual biomass of trout, mean annual number of trout over 15 cm (legal size), and annual production increased significantly during the 3 years following development, but more impressive responses were observed during the second 3 years. Maximum number and biomass and number of legal trout did not occur until 5 years after completion of development. The peak number of brook trout over 20 cm was reached the sixth year after development. Where long‐term studies of aquatic systems are needed to evaluate effects of environmental perturbations, it may be desirable to deliberately delay collection of posttreatment data. Such a start‐pause‐finish sequence of research would provide more valid and less costly evaluations and utilize the time of researchers more efficiently.

Relations entre les caractéristiques de l'habitat et les populations de truites communes (Salmo trutta L.) de la vallée de la Neste d'Aure

“…De nombreux auteurs considèrent les abris comme une des variables de l'habitat physique les plus déterminantes vis-à-vis de l'abondance des truites (LEWIS, 1969 ;HUNT, 1976 ;ENK, 1977 ;FAUSH et WHITE, 1981 ;BOVEE, 1982 ;CUNJAK et POWER, 1986 ;GATZ et al, 1987). NIELSEN (1986) montre que l'abondance des abris peut expliquer de 33 à 74 % de la variation de densités de truites.…”

“…NIELSEN (1986) montre que l'abondance des abris peut expliquer de 33 à 74 % de la variation de densités de truites. L'augmentation du nombre d'abris entraîne une augmentation de la biomasse de truites (BOUSSU, 1954 ;HUNT, 1976 ;NASLUND, 1989). WESCHE et al (1987) indiquent une corrélation significative entre la.surface occupée par les sous-berges et le nombre de truites.…”

Libby Mitigation Program, 2007 Annual Progress Report: Mitigation for the Construction and Operation of Libby Dam.

“…Most of the stream restoration activities that others report either the successes Binns and Remmick 1994;Burgess and Bider 1980;Hunt 1976;House andBoehne 1985 and or failures (Frissell and Nawa 1992;Pattenden et al 1998;Hamilton 1989) typically implemented what we would consider habitat enhancement activities rather than stream channel reconstruction as was the case with each of the projects we completed. Frissell and Nawa (1992) and Pattenden et al (1998) agreed that the risk of failure of stream restoration activities is highest in streams with recent watershed disturbance, high instream sediment budgets, and unstable stream channels.…”

“…Habitat enhancement has been shown to increase the abundance of resident salmonids in streams Binns and Remmick 1994;Hunt 1976;Saunders and Smith 1962;House and Boehne 1986). However, in nearly every study the physical changes to the habitat were sustained with relatively low structure failure rates.…”

“…Many investigators (Hunt 1976;Binns and Remmick 1994) argue that several years are needed for fish populations to fully respond to habitat enhancement. Binns and Remmick (1994) lobby for a minimum of several years of pretreatment data be collected and at least 4-8 years post treatment data collection is necessary for a valid evaluation of fish populations to habitat restoration work.…”