Invasive species ALERT!
Non-native Botryllid tunicates have arrived in Alaska! These tunicates have been found in Sitka, Ketchikan and Homer, Alaska.
The council has been part of a collaborative effort with the Smithsonian Environmental Research Center and the San Francisco State University to monitor for non-native tunicates and to study changes in native marine invertebrate populations.
Tunicates, or sea squirts, are marine invertebrates that attach to hard surfaces such as rocks, piers, boats and docks. Composed mostly of water, they are soft and slimy. Non-native tunicates have been introduced by humans into Alaskan waters.
Tunicates are introduced to Alaska through human activity, often hitching rides from one place to another on ships.
Invasive tunicates can have harmful economic, ecological, or environmental impacts. In uncontrolled numbers, invasive tunicates can damage aquaculture, fishing, or marine gear. They can out-compete or suffocate native oysters and mussels, affecting commercial industries.
What can you do to help?
1. Clean your boat hull before you transit from one harbor to another.
2. Educate yourself and others.
Before moving your boat to a new location, clean your hull. Scrape off all tunicates. Dispose of the tunicates in a dumpster, leave them to dry out on the dock or soak them in a bucket of fresh water for several days. Also check any gear that spends long period of time in the water.
To report potentially invasive tunicates call Alaska Fish and game at: 1-877-INVASIV.
Invasive species ALERT!
The two NIS species below have not been found in Prince William Sound, but pose a serious threat. Contact us if you think you have found either of these species.
Chinese Mitten Crab (Eriocheir Sinensis) Fur-like hairs on the claws of adults. Four spines on each side of carapace. Legs more than twice as long as the width of the carapace.
European Green Crab (Carcinus maenas) Five spines, or teeth, on each side of the fan-shaped carapace. Three rounded lobes on frontal area. Last pair of legs somewhat flattened. Currently found along the West Coast of the United States, the Chinese Mitten Crab and the European Green Crab are considered a serious potential threat due to the proximity of their geographical distribution to Alaskan waters, their ability to survive and adapt in new environments, and the negative ecological impacts they have had in areas already invaded. See another photo of the Chinese mitten crab on the USFWS-Alaska Invasive Species Web site.
Other species of concern
The following non-indigenous species have been identified in Prince William Sound.
Fact sheets below describe each of the Prince William Sound NIS in detail, including information about biology and physiology, dispersal potential, and impacts and control.
Ballast Water Treatment Technology Fact Sheets
PWSRCAC developed the following fact sheets (pdf format) to identify and describe ballast water treatment technologies that may be successfully used to control non-indigenous species introduction into Prince William Sound via crude oil tankers. Both shore-based treatment systems and tanker-based technologies are identified and described in the two general overview sheets below.
To assist in the consideration of shore-based and tanker-based technologies, PWSRCAC developed a ranking system that is included on all the technology fact sheets. The ranking system is explained in its own fact sheet below.
The shore-based treatment systems and tanker-based technologies are further described in the 12 technologies sheets below.