Fish General

Yes. Lamprey and hagfish are both jawless fishes. They are the only living members of the taxonomical class Agnatha (Greek for “no jaws”). 
No. Although sturgeon and catfish can be found in the same habitats and they both have barbels (whiskerlike growths extending from the jaw), they are not closely related. Sturgeon are much more primitive than catfish. There are some catfish sold for...
Yes, sturgeon really are the largest of the freshwater fish. The beluga sturgeon in Russia is the largest freshwater fish in the world. The white sturgeon is the largest freshwater fish in North America. White sturgeon have been reported to reach lengths...
The USGS Grand Canyon Monitoring and Research Center in Flagstaff, Arizona, conducts at least eight trips each year to study endangered fish populations. The USGS is especially interested in the Humpback Chub, but we are interested in all of the fish in...
Coastal marshes provide essential habitat and nurseries for fish and habitat for migratory and non-migratory birds, mammals, reptiles, and amphibians. Scientists cannot at this time predict the effects of brown marsh (sudden coastal marsh dieback) on...
Yes. Gas bladders, more commonly referred to as swim bladders, allow precise control of buoyancy because the volume of gas they contain can be regulated with ease. Two types of swim bladders exist. Some fish have swim bladders with a connection or duct...
This is a very broad question, and difficult to answer without a bit more context. Pollution comes in many forms; chemical, thermal, acoustic, and physical for example. Each of these types of pollution affect individual sturgeons and populations of...