Frozen detritus: a novel nutritious food for juvenile mussels in captive breeding

Abstract

Captive breeding of freshwater mussels is essential for conservation strategies to maintain populations of endangered bivalve mollusks. In the Czech Republic, breeders use detritus from natural sources, preferably from nearby streams and spring areas, to prepare pearl mussels for release into the target localities to reestablish sustainable populations in their native habitats. This strategy is subject to sudden changes, and breeders must consider different detritus qualities between seasons and the unpredictability of weather conditions. Therefore, harvesting natural detritus on a regular basis is challenging and time-consuming, and more samples require more testing, which increases the cost of captive breeding. We proved that juvenile freshwater pearl mussels grew faster when fed detritus stored frozen in a freezer than when fed the same chilled detritus. Therefore, detritus can be harvested under optimal conditions and stored in a freezer for the remaining season, thereby simplifying and reducing mussel conservation costs. Moreover, this approach offers a sustainable, environmentally friendly method that does not require the industrial production of artificial feeds.