Transcript Thorpe_Rusty Crayfish

Rusty Crayfish
Orconectes rusticus
Current Distribution
Background
• Originated in the Ohio River Basin, Kentucky and Ohio.
• Introduced to Wisconsin in the early 1960’s.
• Spread through use as fishing bait, educational purposes, pets.
• Inhabit lakes, ponds, streams, and rivers.
• One female possessing sperm and eggs start a population.
Typical Decapoda(order) Life Cycle
Egg bearing Female
Male and Female
Arrow points to the gonopod legs on a male.
Seminal receptacle found on females.
Negative environmental impacts
• Displace native crayfish species.
- Food consumption
- Disrupt reproduction cycle
- Destruction of ecosystem
- High growth rate
Native Orconectes obscurus
Negative Economic impacts
• Reduction of sporting species
• Decreased recreation usability
• Aquatic maintenance costs
Sparkling Lake, Wisconsin
Sparkling Lake, Wisconsin
Control Methods
• Chemical control methods
• Seasonal Harvest
• Combination fishing restriction and trapping
• Don’t introduce in the first place
Typical Traps
Prevention
• Education of the threats
• Mandatory washing and cleaning of equipment.
• Check points
• Implementation of laws
- PA law makes its illegal for anglers to posses, aquarists to raise, and bait
dealers or pet traders to sell O. rusticus.
Identifying characteristics
Don’t Use Me For Bait!