California Outdoors Q&A

Salmon Carcasses Donated

Q: When adult (returning) salmon are processed for eggs at hatcheries, what happens with the carcasses?

A: CDFW has an agreement to donate Chinook salmon carcasses that are fit for human consumption to the California Emergency Foodlink. That agency then works with food banks throughout California to distribute the salmon that comes from five northern California hatcheries. Nearly 70,000 pounds of fish from the recent fall-run Chinook salmon migration were donated.

Here’s why salmon are available for those donations. Returning adult fish that swim hatchery gates and up fish ladders are anesthetized before they are spawned. Anesthesia methods used at CDFW hatcheries include carbon dioxide and electro-anesthesia, which keep these fish safe for consumption. CDFW is careful not to waste the carcasses and has been working with California Emergency Foodlink for more than 20 years.

Solo Flight vs Flocks

Q: Why do some species of birds fly in groups of hundreds – or thousands – while some fly or live seemingly single?

A: There can be many benefits to living or traveling in groups. Flocks of birds may gather for longer-distance migration or even shorter-distance local movements. Groups of birds also may assemble during the breeding season with many individual birds nesting in a colony. The main advantages of being an individual bird in a flock or nesting colony have to do with safety and finding food resources. Birds within a flock can help alert others to potential predators and other threats. The more eyes there are, the better it is to detect predators. Being in a group can also decrease the chance of any one individual within the flock or colony being taken by a predator. The scientific name for this is called the dilution effect, the more bodies there are the lower the chances of being the individual taken by the predator. Birds in a flock also can improve food-finding and wayfinding for other members within the group. For example, snow geese are a migratory bird that breed in the arctic and overwinter in parts of California and elsewhere in the U.S. and Mexico. The juvenile snow geese hatched that season in the arctic breeding colony have never migrated south. It’s common for juveniles to migrate in family groups with their parents and siblings within the larger flock, which helps juveniles find their way and locate food resources. For bird species that feed on relatively abundant plants or insects, such as waterfowl or small songbirds, it can be beneficial to be in the company of others both for safety and locating food resources.

The primary disadvantage to group living is competition for food and other resources like mates or territory. When a bird must expend a lot of energy to obtain its next meal, such as catching live prey, it can be beneficial to forage alone. For example, many raptors are mostly solitary outside of the breeding season. An individual raptor is in direct competition with its neighbor for limited food resources. Catching live prey, such as small mammals and birds, can require high energy expenditure to obtain. Given the high cost of catching the prey, the raptor benefits most from consuming the prey itself without having to share.

Bears in California

Q: I believe that I may have stumbled upon a grizzly bear in California in June of last year. Is that possible? I live in Siskiyou County, near the Oregon state line.

A:  In California, the native grizzly bear (Ursus arctos, also known as the brown bear) went extinct around 100 years ago, leaving California with just the one bruin, the black bear that inhabits the entire state. It can be easy to mistake a black bear for a grizzly bear though, due to the tremendous variation in black bear colors and sizes we have in California. Many black bears in California possess a brown coat just like their larger and more aggressive relatives. In addition to brown, California also has many animals that are black, dark brown, cinnamon and even some that are blonde. The size of black bears can also vary widely. While most black bear adults are going to be somewhere between 150 to 300 pounds and easy to distinguish from the much larger grizzly adult, there are many more than 300 pounds and some individuals weighing over a whopping 600 pounds, which is heavier than a lot of grizzlies. Grizzly bears are found today in Alaska, Wyoming, Montana, Idaho, Washington and western Canada. Ear shape, shoulder hump, facial profile and claw length are reliable features used by biologists to distinguish between the two types of bear in areas of species overlap.

California’s black bear population has increased over the years. In the early ‘80s the statewide population was estimated to be between 10,000 and 15,000 bears. The current population is estimated to be between 30,000 and 40,000.

Ivory Trafficking

Q: How do wildlife officers tell the difference between elephant ivory and other animals that have ivory such as whales or even warthogs?

A: In a forensics lab! When Assembly Bill 96 was signed (now Fish and Game Code section 2022), it made the commercialization of ivory and rhinoceros horn illegal in California, with limited exceptions. Passage of AB 96 prompted a number of dedicated wildlife officers, legal staff, and a wildlife forensic specialist to work on issues related to the illegal trade of ivory and rhinoceros horn. The law also created funding to support the creation of the California Department of Fish and Wildlife (CDFW) Genetics Research Laboratory.

The laboratory staff are federally certified in the morphological or structural identification of ivory using physical and chemical characteristics. Forensic specialists utilize these techniques to compare against a database of known ivory specimens (tusks and teeth) from ivory-bearing species as well as synthetic ivory items (bones, plastics, resins, etc.) to help identify suspected ivory items.

Since the passing of AB 96, CDFW’s wildlife forensic scientists have become recognized worldwide as experts in ivory identification and even helped to provide training and identification kits for other state, federal and national governments.

Tagging of Hatchery Fish

Q: What’s the purpose of putting tags in salmon that are released from hatcheries?

A: CDFW implants millions of fish each year with tiny metal tags engraved with codes indicating when and from which hatchery a fish was released into the wild. When the salmon return to their release location a few years later, CDFW scientists collect that important information.

The fish are about five months old, living and growing in a hatchery raceway, when they’re brought in for tagging. The adipose fin on the fish (between the dorsal fin and tail fin) is also clipped, which is a visual indicator of which fish have the metal tags, and which ones do not.

The tagging happens at several CDFW hatcheries each year. At the Nimbus Fish Hatchery, east of Sacramento, about a million fish are tagged annually. The fish are about three inches in length when tagged. At roughly the six-month mark, the fish are released.

CDFW Interpretive Services Supervisor Laura Drath explained the importance of tagging salmon.

“The information on the Coded Wire Tag allows us to assess the success of our practices,” said Drath. “We're seeing not only how many hatchery-bred fish are returning, but also which of our release sites are most successful.”

The information retrieved from the tags helps CDFW monitor and adjust management techniques if needed. If a release site is not yielding a good return that site may not be used in the future. CDFW’s goal is to keep the fish population sustainable by using these tools and strategies.

Riverside County Sheep Barrier

Q: Is there an update on the fence construction project meant to keep bighorn sheep out of the community of La Quinta?

A: CDFW is working alongside the U.S. Fish and Wildlife Service and the Coachella Valley Conservation Commission on the construction of about two and a half miles of fencing between the city of La Quinta and the Santa Rosa mountains, in Riverside County. Peninsular bighorn sheep are federally endangered under the Endangered Species Act and are a fully protected species under California Fish and Game Code 4700.

The Peninsular Bighorn Sheep Barrier Project is meant to protect bighorn sheep from hazards of the urban environment in the La Quinta area. The fence will reduce the chances for a bighorn sheep to drown in residential pools or in canals, restrict access to roadways where they have been injured and killed by vehicle strikes and make it less likely that the sheep ingest toxins from decorative plantings.

The goal for the fence once completed is to encourage bighorn sheep to return to the desert slopes that are their natural habitat. Peninsular bighorn sheep have adapted over thousands of years to forage for desert plants and survive dry climates.

In mid-November, CDFW conducted a capture and collar event in which seven sheep were equipped with GPS collars and then released in the same area they were captured. Information gathered from the collars will assist CDFW biologists in tracking herd movement and behavior, as barrier construction continues.

The planning for the barrier began in 2014, with construction expected to be completed in 2024.

Free Hunting Days

Q: When are the next California Free Hunting Days?

A: Under state law the California Department of Fish and Wildlife (CDFW) Director designates two Free Hunting Days. In this license year, they are Nov. 25, 2023, and April 13, 2024. On these days, eligible California residents may hunt without purchasing a California hunting license, provided other requirements are met.

Those requirements include proof of completion of a hunter education course, possession of a valid Free Hunt Days Registration and any required tags, federal entitlements and entry permits. All hunting participants in Free Hunting Days must be accompanied by a hunter at least 21 years of age who possesses a valid California hunting license.

The dates were chosen intentionally to provide the widest variety of hunting opportunities and options for people trying hunting. On Nov. 25, waterfowl seasons and many upland game seasons, from rabbit and squirrel to dove, pheasant, quail and fall wild turkey will be open in various zones throughout the state. April 13, 2024, was chosen with two other popular species in mind, wild pig and wild turkey. More information is available at CDFW’s Free Hunting Days webpage.

Best Time to Visit Nimbus Hatchery

Q: Is this the best time of the year to watch salmon spawning at Nimbus Hatchery, east of Sacramento?

A: November is the start of a four month stretch when the Nimbus Fish Hatchery is most busy, with Chinook salmon returning up the American River for about two months, and then steelhead trout make that trip in January and February. This hatchery is one of 21 operated by CDFW and it attracts the greatest number of visitors – about 65 thousand people annually in addition to about 10 thousand children on field trips.

CDFW Interpretive Services Supervisor Laura Drath said the hatchery is back to full strength after the pandemic, meaning all tours and public spaces are available. The list of activities includes play areas for children and a preschool story and craft program called Tot Time on Sunday mornings. Visitors can feed fish in the raceways, then walk along the river bluff to see salmon in their natural habitat. Finally, it's also possible to watch as fish filled with eggs make their way up the fish ladder to the processing room where hundreds of thousands of eggs are extracted and then raised on-site until they’re large enough for placement into the river. The Nimbus Hatchery produces about 4.5 million Chinook salmon and 430,000 steelhead trout each year.

This hatchery is widely visited and visitor-friendly because it’s located so close to a populated urban area (about 20 miles east of Sacramento). Drath said this facility is in a great position to represent the important work being done by CDFW.

The Nimbus Fish Hatchery is open to the public every day of the year except Christmas Day (rain or shine).

Oil Spill Fingerprints

Q: Can CDFW track down the source of a mysterious oil spill?

A: Within CDFW is the Office of Spill Prevention and Response (OSPR). That’s where the Petroleum Chemistry Lab (PCL) has a staff of chemists whose primary task is determining where spilled oil came from. Hundreds of oil spills or leaks occur in the state annually, with incidents ranging from tanker truck rollovers to pipeline leaks to natural offshore seeps. When it’s not obvious which company or facility is the source of a spill, the PCL steps in.

Petroleum is a mixture of thousands of individual components that indicate the geographic location, age, thermal characteristics and organisms of a geologic oil reservoir. These factors create unique signatures or fingerprints that help chemists identify one oil sample from another. When oil is collected by CDFW during an investigation, OSPR’s scientists can identify the source of that spill by comparing the fingerprints to samples from the most likely potential sources. That work can lead to the collection of fines and even criminal charges in cases when the responsible party isn’t admitting fault. The PCL is one of just a handful in the country doing this work.