Volunteers eagerly took to the warm water in Crystal Spring outflow on Saturday morning to strategically remove cattails (bulrush was left uncut along the outflow). The group was composed of 14 volunteers from Las Vegas and Pahrump, including members of the Amargosa Conservancy, young men from the Continuum of Care Program of Clark County, and the Boy Scouts in Pahrump. During the 4-hour event, two dump-truck loads of cattail were removed from approximately 200 yards of Crystal Spring outflow. Success!
So why do we cut cattails? When the Death Valley Expedition came through the Ash Meadows area in the 1880s, they observed that the dominant emergent aquatic vegetation was chairmaker’s bulrush (Schoenoplectus americanus). Southern cattail (Typha domingensis) also was present, but did not dominate spring outflow habitats in Ash Meadows. During the 1950s-1970s, large-scale farming and ranching resulted in the diversion of most spring outflows into channelized ditches. Among other things, channelization of the spring outflows changed the hydrology of the ecosystem, benefiting cattail more than bulrush. What we are left with today is an overabundance of cattail growth in many of the streams at Ash Meadows.
Uncontrolled, cattails have invaded the spring system causing changes in water velocity, water temperature, canopy cover (e.g. shading), and ultimately the community structure of the spring system. These changes can negatively impact numerous aquatic species, often favoring non-native aquatic species, such as red swamp crayfish (Procambarus clarkii), over native species, such as the endemic Crystal Spring springsnail (Pyrgulopsis crystalis) and the endangered Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes), both shown here. The springsnail is only 1 mm long and requires water warmer than 25oC to survive. The pupfish is the only native fish still occupying Crystal Spring, is generally smaller than one inch long, and requires warm water (>25oC) to reproduce. Both of these species benefit from cattail removal.
For more than a decade, Ash Meadows NWR staff, along with volunteers, has been controlling invasive cattail growth in springs throughout the Refuge. Crystal Spring outflow is one location where cattail removal is a priority. We wish to thank all the volunteers who helped improve our wetlands on December 4th!
By: Alyson Mack, Great Basin Institute Environmental Education & Outreach Specialist