Science Spotlight

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  • April 29, 2019

One large spiny lobster and four smaller lobsters lined up on green mat on side of boat.

Scuba diver next to rocks and kelp underwater holding up spiny lobster and calipers.

The April 30 deadline to turn in California spiny lobster report cards is fast approaching – and CDFW needs your catch data!

The information collected from these is enormously helpful to CDFW scientists who monitor the harvest, amount of fishing effort and the gear used in the recreational fishery. Although CDFW has considerable information about the commercial lobster fishery from landing receipts and logbooks, there was very little reliable information on the magnitude of the recreational lobster catch and fishing effort prior to the launch of the lobster report card program.

CDFW first began requiring lobster fishers to fill out and turn in harvest report cards 10 years ago, in the 2008-2009 season. Persons taking or trying to take lobsters were required to possess, fill out and submit spiny lobster report cards at the end of the season.

By the 2013-2014 sport fishing season, CDFW rolled out a new spiny lobster report card system with new reporting requirements to improve the estimates of the recreational fishery harvest. The new reporting requirements included a non-return penalty fee if cards were not returned at the end of the season. Since then, card return rates have improved greatly. It could be argued that the new reporting requirements encourage more people to return their lobster report cards, which in turn has improved estimates of sport lobster catch and effort.

Results determined from report card returns after the 2017-2018 season showed a 50 percent return rate of more than 16,000 cards, compared to 22 percent (approximately 6,000 cards) after the 2008 season. In 2017-2018, more than 85,000 lobsters were reported kept versus nearly 48,000 reported in 2008. Based upon the numbers from 2017-2018, more than 171,000 lobsters were estimated taken by the recreational fishery. When added to the recorded commercial harvest for this season, recreational fishermen accounted for 31 percent of the entire California spiny lobster harvest for the season.

The cost for this year’s spiny lobster season report cards was $9.27 when purchased from CDFW offices, with a small (about 2%) surcharge applied when purchased from other vendors. Report cards are available in most places where sport fishing licenses are sold, including tackle shops and sporting goods stores, or can be purchased online. The funds raised by the sale of lobster cards are earmarked for CDFW projects, including those specifically focused on the lobster fishery.

Daily bag and possession limits are seven lobsters per person. No more than one daily bag limit may be taken or possessed by any one person unless otherwise authorized, regardless of whether they are fresh, frozen or otherwise preserved. This means that if you have a limit of seven lobsters at home, you cannot go out and get more lobsters until the first limit is disposed of in some way (eaten, given away, etc).

People often ask why commercial fishermen are allowed to use huge traps while recreational fishermen are restricted to using hoop nets. Many think this doesn’t seem fair, but CDFW is mandated by law to allow for the sustainable use of lobster by both the commercial and recreational fishing sectors. While our laws say that recreational fishermen are entitled to harvest for sport (and not subsistence use), commercial fishermen must make a living off the resource. The commercial lobster industry is highly regulated, with a fixed number of permits, and commercial fishermen are required to use traps with strict regulations concerning mesh size and escape ports that allow large numbers of sub-legal sized lobsters to come and go freely from traps. Recreational lobster fishing is considered a sport and not meant for subsistence.

CDFW would like recreational users to enjoy this resource. The number of recreational participants is not restricted, and hoop nets and diving are both very effective methods of recreational take. Finally, there are large productive areas that are closed to commercial lobster fishing but open to recreational lobster fishing, such as Santa Monica Bay, San Pedro Bay, San Diego Bay, the lee side of Catalina Island and many bays and jetties.

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Some interesting facts about these popular crustaceans: California spiny lobsters are believed to live 50 years, or more! The males have been recorded up to three feet long and weighing 26 pounds. Today, lobsters over five pounds are considered trophy-sized. For more information on spiny lobster biology, please check out our link opens in new windowCalifornia Spiny Lobster brochure (PDF).

CDFW Photos.

Media contacts:
Carrie Wilson, CDFW Communications, (831) 649-7191
Kirsten Macintyre, CDFW Communications, (916) 322-8988

Categories: General
  • April 19, 2019

Brown vials with green tops in a dark gray tray.

Man wearing white lab coat holding up two sheets of white paper with graphs.

You've seen television forensic dramas where sleuths use science to help find a killer. What many don’t know is these same types of similar techniques like fingerprinting can help investigators track down the source of an oil spill. The California Department of Fish and Wildlife’s Petroleum Chemistry Laboratory (PCL), located east of Sacramento in Rancho Cordova, is tasked with determining the origin of oil spills, which can lead to criminal charges in California. They do this by comparing the chemical properties of the oil to known sources from around the world. The end result is sound scientific evidence that can hold up in a court of law.

Media Contact: Steve Gonzalez, CDFW OSPR, (916) 322-1683

Categories: Wildlife Research
  • April 12, 2019

Laminated sign with fish that reads attention anglers attached to old wooden sign on metal post in grassy area with lake and mountains in background
Lake-side signage lets anglers know Kirman has recently been stocked with wild brook trout and asks for help from anglers in competing a brief survey about their fishing experience.

Seven people in waders and machine backpacks holding nets and yellow poles in stream.
CDFW fisheries biologists electrofish Silver Creek in Mono County to remove non-native brook trout to reduce competition with native cutthroats.

Hand palm facing up with several water bugs in palm
The tremendous amount of aquatic life within Kirman Lake provides a nearly unlimited food supply for transplanted brook trout from Silver Creek and transplanted Lahontan cutthroat trout from Heenan Lake. Kirman itself has no spawning habitat and is dependent on trout plants from CDFW to maintain the trophy trout fishery.

Small speckled fish laid on top of measuring tape and wooden board.
Before release into their new home in Kirman Lake this fall, brook trout were measured and their adipose fins clipped. CDFW scientists plan to track their growth rates with the help of voluntary angler surveys.

It’s a question that has been asked by more than a few eastern Sierra trout anglers: What happened to the fishing at Kirman Lake?

Kirman, a small backcountry lake north of Bridgeport in Mono County, has long been heralded as one of the very few places in the state where anglers could catch trophy brook trout.

While many high-elevation waters hold overpopulations of stunted brook trout measured in inches, the brook trout in Kirman were measured in pounds. Fish in the 2- to 4-pound class were common with numerous reports of brookies exceeding 5 pounds.

The lake requires a moderate, 3-mile hike to reach – just enough distance and difficulty to discourage casual anglers and help minimize some of the fishing pressure, particularly with so many great trout fishing options nearby. The lake is a special-regulations water with limited harvest. It is open to fishing during the state’s traditional trout season from the last Saturday in April to Nov. 15. Only artificial lures with barbless hooks may be used. Only two trout can be kept – with a minimum size limit of 16 inches.

Kirman was a destination known well beyond the confines of Mono County.

Fly fishing author and instructor Denny Rickards included Kirman in his book “Fly Fishing the West’s Best Trophy Lakes.”

Rickards writes, “Those who have made the trek and landed one of these beautiful trout know what a delicate lake it is. Part of the promise here is more than just big brook trout – the lake also harbors big cutthroat. However, the cuts aren’t the primary focus of those who fish here. It’s those big, beautiful brookies that bring fishermen up the trail.”

Author Bill Sunderland likewise highlighted Kirman in his book “Fly Fishing California Stillwaters.” He writes, “The fish here, both brook trout and Lahontan cutthroats from Heenan Lake, grow exceptionally fast. A four-year-old brookie can be twenty inches long and weigh four pounds. Many of them are football-shaped, the result of their rapid growth.”

In recent years, however, the brook trout seemingly disappeared with anglers reporting fewer catches with no brookies in the mix. Fishing reports from Kirman dried up as well at local tackle shops with fewer anglers apparently making the trek.

What happened to Kirman Lake and its trophy brook trout is no mystery to CDFW fisheries biologists, who are committed to restoring the lake to its former glory.

“There’s no spawning habitat,” explained Jeff Weaver, a senior environmental scientist with CDFW who oversees the department’s Heritage and Wild Trout Program. “All the fish in Kirman Lake have been stocked to provide the recreational fishery.”

Brook trout were planted annually by CDFW until 2015 when hatchery problems prevented the raising and delivering of the fish.

What Kirman lacks in spawning habitat it makes up for in food abundance. Unlike many high-mountain lakes where trout eke out an existence in near-sterile conditions, Kirman is the equivalent of a 24-hour, all-you-can-eat buffet. The lake is loaded with all manner of aquatic invertebrates -- water boatman, dragonflies, mayflies and midges – along with high-protein leeches and shrimp-like scuds. The heavy population of scuds accounts for the tremendous growth rate and size of Kirman brook trout.

When Russell Black, CDFW’s new fisheries supervisor for the Inland Deserts Region, learned about the lack of hatchery plants and the poor state of the once-great fishery, he came up with a simple yet creative solution.

This past fall, work was underway at nearby Silver Creek to prepare the water for the eventual restoration of native Lahontan cutthroat trout. CDFW biologists electrofished Silver Creek to remove the non-native brook trout there to minimize competition with the native cutthroats.

Black’s idea: Take those brook trout and transport them to Kirman.

More than 1,300 Silver Creek brook trout in a variety of sizes were relocated to Kirman. Prior to release, the fish were measured and their adipose fins clipped. CDFW biologists encourage anglers at Kirman this upcoming trout season to record their catch and fishing experiences at angler survey boxes lakeside so they can track the transplanted Silver Creek brook trout.

Given the exceptional growth rate at Kirman, CDFW biologists expect anglers to get into some quality fish by the fall.

Even as CDFW shifts its statewide trout hatchery focus to raising and stocking native trout as opposed to non-native brown trout, brook trout or even domesticated strains of hatchery rainbow trout, biologists see a future for trophy brook trout in Kirman and are exploring options to resume annual hatchery stocking.

“Kirman Lake is one of those celebrated fisheries where we weigh management in favor of continuing that recreational fishery,” said CDFW’s Weaver, who himself has fished Kirman a dozen or so times over the past 20 years. “Kirman Lake is managed as a trophy trout fishery and we intend to continue to manage it as a trophy trout fishery. We’ve just been on pause as a result of the lack of stocking.”

The pause may be over, though, as CDFW intends to maintain the supplemental stocking from Silver Creek until regular hatchery plants can resume.

CDFW Photos. Top Photo: This small brook trout was one of many relocated this fall from Silver Creek to Kirman Lake, where it could potentially grow into a trophy-sized fish awaiting anglers this trout season.

Media contact: Peter Tira, Communications, (916) 322-8908

Categories: Wildlife Research
  • April 2, 2019

The latest issue of California Fish and Game, Vol. 105, Issue 1 (PDF), focuses on marine species, bringing new insights and understanding of several fish species found off the California coast.

In A very long term tag recovery of a California scorpionfish (Scorpaena guttata) (PDF), Roberts and Hanan report the remarkable recovery of a tagged scorpionfish that had been at liberty far longer than any previously recaptured scorpionfish. The recovery was made during a four-year mark-recapture study on nearshore groundfish off southern and central California. More than 32,000 fish were recaptured, with an average of 408.8 days at liberty. The study results indicate that scorpionfish demonstrate strong site fidelity, given that a majority of the fish were recaptured within 5k of their original tagging site. The scorpionfish that is the subject of the article was tagged in 2004. It had been at liberty for nearly 14 years (5,048 days). After removing the tag, the fisherman who captured the fish reported that he released it “unharmed and looking very healthy.”

Another paper reports on a method for estimating the age of roosterfish using dorsal fin spines (PDF). According to authors Chavez-Arellano et. al, the roosterfish is considered a prized species by the sport fishing community and provides a significant economic benefit to the Mexican tourism industry. However, little is known about its biology, ecology, and movement patterns. The authors embarked upon a study to assess which sections of roosterfish dorsal fin spines have the most legible indicators of growth for use in future aging studies. Their work provides the initial basis from which future aging studies can be conducted.

Finally,Primary and secondary nursery areas for leopard and brown smoothhound sharks in San Francisco Bay, California (PDF), summarizes a 31-year study to determine primary and secondary nursery habitats for leopard and brown smoothhound sharks within South San Francisco Bay, adding new knowledge to the biology of both species.

As it has for the past 105 years, California Fish and Game continues to publish high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife. We look forward to witnessing the contributions of the next installment.

CDFW Photo.
Media Contact:
Lorna Bernard, CDFW Communications, (916) 322-8911  

Categories: California Fish and Game Journal