Texas Parks and Wildlife Status: Positive
Zebra mussels or veligers (larva) have been detected on more than one occassion.
River Map
Blue triangles show USGS data-collection locations.
| Most Recent Detection | First Date Detected | |
|---|---|---|
| 07/19/2023 | 0.04 per Liter | 10/09/2012 |
Larvae detection counts are averaged across all sampling sites.
Zebra mussels typically spawn in the spring and autumn as microscopic, free swimming larvae called 'veligers'. The USGS uses fine mesh nets to sample for larvae during the spawning season.
| Most Recent Detection | First Date Detected | |
|---|---|---|
| 07/19/2023 | 10/09/2012 | |
Adult detection counts are averaged across all sampling sites.
At the end of their larval stage, zebra mussels attach to a substrate and metamorphose into juveniles. The USGS conducts both visual and SCUBA inspections, and deploys artificial substrates as passive samplers, to get a estimate of the juvenile and adult zebra mussel populations.
Water-quality monitoring is important for studies of zebra mussel survival, growth, and reproduction. Water-quality data are also important for risk assessments for zebra mussel infestation.
Water-Quality Graphs
Select a parameter to view graphs of data collected at all Elm Fork Trinity River sites.
Select a site to view all water-quality data in the USGS National Water Information System (NWIS).