eDNA a useful tool for early detection of invasive green crab
by Michelle Ma, University of Washington
February 15, 2022
European green crabs feast on shellfish, destroy marsh habitats by burrowing in the mud and obliterate valuable seagrass beds. The invasive species also reproduces quickly, making it a nightmare for wildlife managers seeking to control its spread in Washington’s marine waters.
Last month, Gov. Jay Inslee issued an emergency order in response to more than 70,000 crabs caught on Lummi Nation land as well as dramatic increases in crab populations on Washington’s outer coast and other locations in Puget Sound in recent years.
As the green crab invasion in the state worsens, a new analysis method developed by University of Washington and Washington Sea Grant scientists could help contain future invasions and prevent new outbreaks using water testing and genetic analysis. The results, published online Feb. 6 in the journal Ecological Applications, show that the DNA-based technique works as well in detecting the presence of green crabs as setting traps to catch the live animals, which is a more laborious process. Results suggest these two methods could complement each other as approaches to learn where the species’ range is expanding.
Read the Ecological Applications paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.2561