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Layzer, J. B. (1996). The importance of habitat hydraulics in the restoration of native freshwater mussels. Journal of Shellfish Research. 15:485.

Freshwater mussel populations in North America have been devastated by a wide array of physical and chemical perturbations. In some cases, habitat destruction and the loss of mussel populations is essentially permanent as in the case of the construction of dams which inundate riverine habitat, change water quality, and eliminate hosts fish populations. In many other cases, the factors responsible for the extirpation of mussel populations have largely been corrected and conditions may now be suitable for the reestablishment of mussels; however, it is suggested that during the intervening time between the extirpation of mussels and improvement in stream conditions other factors affecting stream hydraulics may prevent the successful reintroduction of mussels. In particular, land-use practices within watersheds may have profoundly affected stream hydrographs by increasing peak discharges following precipitation and decreasing base flows during dry periods. Lower base flows may expose mussel beds, eliminate settlement of juveniles from otherwise suitable habitat, and affect host fish population dynamics and movements. Conversely, results of recent research indicate that high shear stress associated with peak discharge is likely responsible for unsuccessful settlement of juvenile mussels in a headwater stream. Measuring or modelling simple hydraulic variables such as mean water column velocity is inadequate for assessing the affects of altered stream hydrographs on potential mussel habitat. In contrast, complex hydraulic variables such as shear stress and Reynolds boundary number are potentially better predictors of hydraulically suitable sites for mussel reintroductions.