Assessment and Monitoring

Freshwater ecosystems are home to more species than either marine or terrestrial environments making them some of the most important ecosystems on the planet.  

Freshwater ecosystems also support valuable recreational fisheries, provide inland shipping channels and renewable hydropower, provide clean water for millions of people, and even protect communities from floods. Despite their global importance, freshwater ecosystems and the species that inhabit them have been heavily impacted by habitat loss, aquatic invasive species invasive species
An invasive species is any plant or animal that has spread or been introduced into a new area where they are, or could, cause harm to the environment, economy, or human, animal, or plant health. Their unwelcome presence can destroy ecosystems and cost millions of dollars.

Learn more about invasive species , and pollution. In the United States alone, over fifty aquatic species have already been declared extinct by and many others are critically endangered or threatened.  

To track the status of our freshwater resources, our Fish and Wildlife Conservation Offices specialize in collecting information on fish populations and their habitats nationwide.  

The offices operate monitoring programs throughout the year in watersheds across the country. The data collected by these programs provide information critical to effectively managing fisheries, preserving, and restoring aquatic habitats, and assessing management strategies.  

How many ways can you count fish?  

Biologists catch and mark fish for future study, track remnant DNA that species leave behind in the water column, and work with anglers to monitor catch and learn about trends in seasonal patterns or invasive species presence. All this information on the status and trends of fish populations is used to frequently evaluate the efficacy of fishing regulations, the success of habitat improvements, and the overall health of fisheries nationwide.  Using this information, managers can adjust key management strategies or conservation decisions as needed.  Further, monitoring and assessment data provided by our conservation offices is providing valuable insight into the impacts of  climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.

Learn more about climate change  on fisheries and the measures we need to protect them.  

We use data to protect wildlife and restore habitat.  

Fish and Wildlife Conservation Offices measure fish population responses to habitat alterations. This is an invaluable tool that can be used to measure the success of habitat restoration projects. As a result, we have been able to adapt emerging fish passage fish passage
Fish passage is the ability of fish or other aquatic species to move freely throughout their life to find food, reproduce, and complete their natural migration cycles. Millions of barriers to fish passage across the country are fragmenting habitat and leading to species declines. The U.S. Fish and Wildlife Service's National Fish Passage Program is working to reconnect watersheds to benefit both wildlife and people.

Learn more about fish passage technologies to meet local needs, apply lessons learned from riparian riparian
Definition of riparian habitat or riparian areas.

Learn more about riparian area restoration to other parts of the country, and provide critically needed oversight to partnership efforts to restore fish habitat from mountain streams to the coast.