Published April 1991. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
What ancient animal in modern times has a primitave spinal cord that may resemble the first vertebrates on earth, spends most of its life stuck to a boat or rock, produces an exoskeleton made of cellulose and is more associated with plants than animals? Tunicates are marine invertebrate filter feeders...
Revised July 1994. A more recent revision exists. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Crayfish are one of the most threatened groups of animals in the world. About 45 percent of North American crayfish species are considered to be at risk of extinction. However, a few crayfish species are among the world's most invasive freshwater organisms. Taking into consideration that invasive crayfish are the...
The nutria is a large, semi-aquatic rodent native to South America. Nutria were introduced to the United States for their fur. After a boom in nutria ranches during the 1930s, the animals escaped or were released from fur farms in the Pacific Northwest, Louisiana and other states, where theyare now...