Fish

Closing the loop on sustainable aquaculture

Inside the world’s first caviar farm that uses fish waste to grow vegetables

On a farm just outside of Sacramento, hundreds of prehistoric-looking fish swim around in 50-foot diameter tanks. These are white sturgeon, the largest freshwater fish in North America. They’ve been around since dinosaurs, can grow more than 7 feet long and lay hundreds of thousands of eggs at a time. The roe of these sturgeon are harvested for a boutique food producer regally named Tsar Nicoulai Caviar.

Walleye fish populations are in decline

Study a warning signal for popular game fish

Walleye, an iconic native fish species in Wisconsin, the upper Midwest and Canada, are in decline in northern Wisconsin lakes, according to a study published this week in the Canadian Journal of Fisheries and Aquatic Species.

Coping With Climate Stress in Antarctica

Some polar fish can cope with warming or ocean acidification, but not both together. Some Antarctic fish living in the planet’s coldest waters are able to cope with the stress of rising carbon dioxide levels in the ocean. They can even tolerate slightly warmer waters.

A Fish Story

Spring-fed waters a critical habitat for cold-water fish   Rainbow trout like their water cold. As the climate changes and temperatures rise, cold-water fish species such as trout and salmon don’t fare well in waterways that run low and warm.

“Native fish in California are imperiled throughout the state,” said Carson Jeffres, field and lab director at the UC Davis Center for Watershed Sciences. “During the drought, we saw a dramatic change in the aquatic habitats that were available.”

Can We Eat Fish and Protect it too?

Scientists help clarify labels and shore up supply  

Seafood is low in fat, high in protein, and a great source of Omega 3 fatty acids, which doctors say can boost brain development and help prevent ailments like depression, arthritis, and heart disease.

Health benefits are one reason people are eating more fish. The United Nations reports that global per capita fish consumption has hit a record high and continues to climb.

Can fisheries sustainably keep up with rising demand? What is “sustainable seafood” anyway?

Koi refugees

CABA cares for 33 fish rescued in wine country fires  

Thirty-three koi swim in sanitized tanks at the UC Davis Center for Aquatic Biology and Aquaculture (CABA). They are refugees from fires that ravaged hundreds of thousands of acres in Santa Rosa and throughout the wine country, destroying more than 6,000 homes.

“In some cases, the fish were rescued from homes that were completely burned down, so the koi are all that are left,” says CABA Director Linda Deanovic, lifting a tank lid to peer inside at a golden, incandescent koi.

The Last Stop: When There's Nowhere Colder to Go

How climate change is affecting polar fish at the tip of a warming world  

Fish have been migrating to cooler water over the last several decades as the ocean warms. But in Antarctica, the coldest place on the planet, polar species have nowhere to go.

Preliminary research by a UC Davis animal scientist shows that some polar fish have been able to acclimate to warm water or to higher levels of carbon dioxide, but not to both.

DNA Test Reveals Conservation Gaps

Study Reveals Evolutionary History of Imperiled Salmon Stocks

New technologies for analyzing DNA may transform how imperiled species are considered and managed for conservation protection, according to a study published today in the journal Science Advances and led by the University of California, Davis.

Social fish could save the reef

The social eating habits of fish may play a central role in protecting coral reefs, according to a study from the University of California, Davis, published April 10 in the journal Proceedings of the National Academy of Sciences.

Fish provide a critical service for coral reefs by eating algae that can kill coral and dominate reefs if left unchecked. The study, which analyzed the social feeding behavior of reef fish, suggests that overfishing not only removes vital algae-eaters, but it may cause remaining fish to eat less.

Freshwater or Saltwater? Why not both?

Researchers find salt-tolerant gene in tilapia

Most fish live either in freshwater or saltwater, but others, including tilapia, have the remarkable ability to physiologically adjust to varying salinity levels — a trait that may be critically important as climate change begins to alter the salinity of ocean and coastal waters as well as the water in desert lakes and creeks.