The Nooksack Dace is a form of the Longnose Dace (Rhinichthys cataractae
). "The Nooksack Dace is an undescribed genetically and morphologically distinct form of the Longnose dace endemic to southwestern BC" (Eric Taylor, pers. comm. 2011).
Of the three forms of the Longnose Dace present in BC, the BC Conservation Data Centre tracks Rhinichthys cataractae--Chehalis lineage (Nooksack Dace).
Very little is known about the lifecycle of the Nooksack dace, but it is thought that they spawn at night, when the eggs are "dropped on the rocky bottom of a shallow, fast moving stream" (McPhail 2007). It is smaller than the longnose dace, and is found in the Nooksack River system in the lower Fraser Valley, where it is reported from four creeks: Bertrand, Cave, Fishtrap, and Pepin. It is critically imperiled in BC, and is listed as federally endangered by COSEWIC (Committee on the Status of Endangered Wildlife in Canada). It is restricted in global range to northwestern Washington and southwestern British Columbia, where it evolved in a glacial refuge. McPhail (2007) says: "The Nooksack dace is part of the “Chehalis fauna”, a group of fish that originated in the unglaciated areas south of Puget Sound during Pleistocene glaciation". Threats to this species include sedimentation and general habitat degradation, and habitat loss. Read more about the Nooksack dace.
Read the federal Recovery Strategy for this species.