The Spread of Invasive Asian Clams (Corbicula fluminea) in the Raystown Branch of the Juniata River and Other Streams in the Huntingdon Area

• Ryan Branton

  Juniata College

  Author

• Lauren Mahkovic

  Juniata College

  Author

• Matthew McCleary

  Juniata College

  Author

• Eli Ober

  Juniata College

  Author

Our study focused on the spread of the invasive Asian Clam (Corbicula fluminea) along 10 sites in the Raystown Branch of the Juniata River, Lake Raystown, and its tributaries. Based on our results, we determined that the invasive Asian clam was more prevalent in the sites that had a higher conductivity. This is because organisms that have a hard outer shell or exoskeleton need higher calcium levels to maintain them. Other factors that impacted the presence of freshwater clams were water velocity and depth. In many cases, if the location we were surveying had high water velocity there were very few or no clams found. The implication of this is that clams like to remain stationary, as it allows them to filter their nutrients out of the water more efficiently, fast moving water disrupts this because the nutrients pass by too quickly, without giving the clams a chance to filter it out. This would result in many of the clams dying off because of insufficient nutrients. One final factor that we concluded impacted the spread of Asian Clams at our different locations was pH. Areas with lower pHs would make it more difficult for these locations to harbor clams. Lower pH or higher acidity dissolves and weakens the clams’ outer shells which would make them more vulnerable to predators like raccoons or aquatic birds. Ultimately no native clams were found over the course of this study. All live clams and clam shells found in sampling areas were from the invasive Asian Clam.

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