Persistent surface water pools within non-perennial streams provide critical refuges for freshwater species by facilitating their survival during extended dry periods. However, our understanding of how pool water levels recede is limited, hindering our ability to quantify and predict aquatic refuge persistence. We characterise variations in water-level recession rates based on one year of water-level measurements in five non-perennial streams. Most of the observations show that the water level recedes at a constant rate after streamflow ceases in our study streams, a rate often significantly higher than that during low-flow periods. However, water-level recession rates varied considerably amongst cease-to-flow periods within pools in the same non-perennial stream and between nearby streams. The constancy of water-level recession during a cease-to-flow period is applicable to other non-perennial streams, but a detailed understanding of the factors influencing recession rates is needed for prediction in ungauged streams and identifying persistent aquatic refuges across river networks.

非常年河流中的持久地表水池通过促进淡水物种在长时间干旱期间的生存，为淡水物种提供了重要的避难所。然而，我们对泳池水位如何下降的理解有限，阻碍了我们量化和预测水生避难所持久性的能力。我们根据五个非常年河流的一年水位测量来描述水位衰退率的变化。大多数观察结果表明，在我们的研究溪流中水流停止后，水位以恒定的速度下降，该速度通常明显高于低流量期间的速度。然而，在同一非常年溪流中的水池内和附近溪流之间的停水期，水位衰退率差异很大。