Crayfish Corps Volunteers Needed at Valley Forge

Valley Forge National Historic Park needs volunteers to help wage battle against nature Saturday from noon to 3 p.m.

Each year, members of the Crayfish Corps join National Park Service staff to help clear rusty crayfish out of Valley Creek. According to the park’s website, the species invaded the creek in 2008 and can cause significant damage to the local ecosystem if left unchecked.

“Our long-term goal is to maintain a ratio of one rusty crayfish or less for every four native crayfish present in Valley Creek,” the site says.

The rusty crayfish is bigger, more aggressive, and eats up to twice as much as native crayfish in Valley Creek. They are able to eliminate all other crayfish species through direct competition for food and shelter and increasing the susceptibility of native crayfish to predators. Rusty crayfish also may reduce the amount of aquatic vegetation, reduce aquatic insect populations and ultimately negatively effect large predators such as trout.

Originally from the Ohio River Basin, this crayfish has been transported to new environments throughout the northeast primarily by bait fishermen, biological supply houses, aquaculture, and the pond and aquarium trade.

Crayfish Corps is active between May and August in order to catch the most rusty crayfish and to allow the stream time to rest. Crayfish removal is accomplished using hand nets. Participants of all ages are welcome to join, and park staff will provide necessary training and equipment including nets and a limited number of hip boots. Participants should wear their own closed-toe water shoes if possible.

First-timers will receive a button, and members can receive a t-shirt after participating three times.

Crayfish Corps dates for 2015 include:

• May 30, noon to 3 p.m.
• June 13, noon to 3 p.m.
• June 20 and 27, 9 a.m. to noon
• July 11, 18 and 25, 9 a.m. to noon
• August 1, 8, 15, 22, and 29, 9 a.m. to noon
• September 12 and 19, 9 a.m. to noon