What is a fish? At first, this might seem like an easy question to answer, but it is difficult to define what makes a fish a fish because there is so much diversity among animals that we consider to be fishes. There are more than 27,900 species of fishes alive today, ranging in length from 8 mm to 12 m, and living in marine and freshwaters environments as hot as 104°F/40°C and as cold as 28°F/-2°C.
What characteristics unite such a diverse group of animals?
- have a relatively small brain protected by a braincase and an obvious head region with eyes, teeth, and other sensory organs
- are vertebrate animals that live in the water. Vertebrate means they have a spinal cord surrounded by bone or cartilage.
- have gills that extract oxygen from the water around them
- breathe primarily with gills rather than lungs
- have paired limbs, in the form of fins that aid in locomotion
- are unable to regulate their own internal body temperatures
- are covered with scales that protect their bodies
There are many exceptions to these guidelines. For example, hagfish aren't vertebrates and don't have scales; mudskippers can live outside the water; lungfish use lungs to breathe; lampreys don't have paired fins; and tuna are warm blooded! To make matters more confusing, even though jellyfish and crayfish have the word ‘fish’ in their name, they aren’t actually fish - jellyfish are from a group of animals with specialized cells to capture prey and crayfish are crustaceans.
Fish play an important role in the environment. They feed on nearly all types of plants and animals, they provide a home for other organisms such as bacteria and crustaceans, and they are eaten by many other types of animals, including humans. The most common threats to any fish species include overfishing, factory fishing, bottom trawling, bycatch, development, pollution, and climate change.
Point Reyes National Seashore is surrounded on nearly all sides by the Pacific Ocean, but it also has fresh water lakes, ponds, creeks and other streams that act as important habitat for fish. The National Park Service staff have recorded over 130 different species of fish in the park from the small Mosquito ish to Great White Sharks. While park staff are interested in all types of fish, they focus their conservation efforts at Point Reyes on three species of special concern, including: Coho salmon (Oncorhynchus kisutch), Steelhead trout (Oncorhynchus mykiss irideus), and the Tidewater goby (Eucyclogobius newberryi).
The first two species use several of the coastal streams within and surrounding Point Reyes National Seashore throughout their lifecycle, while the Tidewater goby is found exclusively along Tomales Bay. These three species are all listed as threatened or endangered species, and are monitored closely by the National Park Service. The endangered tidewater goby was rediscovered living in a channelized creek in the southen end of Tomales Bay during a study conducted as part of the Giacomini Wetlands Restoration Project. This small 2-inch fish is endemic to California and is found primarily in waters of coastal lagoons, estuaries, and marshes. The species numbers have dropped dramactically over the years due to changes in drainage, water quality, introduced predators, and drought.
Check out more Fascinating Fish Facts from NOAA or scroll down for more information on what's happening in the park and around California.
Best Time to View
Fish are very unpredictable, but if you are close to the water, or are taking part in water activities like kayaking, canoeing, or swimming you may see various fish species including Leopard sharks and bat rays along Tomales Bay, or see spawning salmon in the creeks in fall and winter after storm events.
Best Place to View
Salmon and Steelhead: Olema, Lagunitas, Redwood, and Pine Gulch Creeks
Other fish: Tomales Bay, Abbotts Lagoon, Bass and Pelican Lake, and of course in the ocean!
Recreational and Sport Fishing
Fishing is closely regulated in the park and is subject to California State Fish and Wildlife regulations and the California Marine Protected Areas and Marine Life Protection Act. It is the individual's responsibility to be familiar with the state laws pertaining to the area in which he or she intends to fish, and with the species and limits of fish they take. A valid state fishing license is required and is monitored by park and local officials.
Join the National Park Service's Coho Salmon and Steelhead Monitoring Program and help observe fish and collect data.
- Point Reyes National Seashore Fish Species List
- Fish Assemblages in the Giacomini Wetlands
- Giacomini Weltands Fish Composition Graph Pre- and Post-Restoration
- California Department of Fish and Wildlife - Coho Salmon
- California Department of Fish and Game - Steelhead Trout
- Fish of Special Concern in California