The native fish of Yosemite including the riffle sculpin, hardhead, Sacramento pikeminnow and California roach. Most of these can only be found in the native elevations. The numerous waterfalls in the park prevent the fish from migrating to upper levels of the rivers, leaving most water bodies in Yosemite fishless.
A variety of non-native fish species has also been introduced throughout the park, such as trout, smallmouth and bluegill. However, being predators, trout impacted the natural ecosystem of the park in a negative way, endangering the other native species of amphibians. This is why they were removed in large numbers from the water bodies of the park.
If you’re planning to fish while at Yosemite, you need to go through the fishing regulations to know which types are to be caught and how much you’re supposed to catch and possess.