Planter trout sterile, but they get bigger

Question: A friend told me state Fish and Wildlife fish hatcheries are now producing and stocking triploid fish. Is this true?

— Anonymous

Answer: Yes! These catchable, sterilized rainbow trout are produced by California Department of Fish & Wildlife fish hatcheries. Triploid fish have an extra set of chromosomes (3N) as a result of pressure treatment, combined with carefully monitored temperature and time precision during egg fertilization. The resulting fish are sterile, making them a more ecologically sound option for recreational fishing in many waters across the state. The fish perform for anglers like a diploid (fertile) fish, many grow larger than the fertile diploids, and they are increasingly being produced in other states for recreational stocking.

In fact, new legislation that went into effect Jan. 1 requires the CDFW to sterilize nearly all fish planted for recreational purposes. This has been in place for decades and requires no manipulation of the cell genomes — no genes are modified or transferred in this process. The carefully applied pressure during fertilization simply encourages the retention of an extra set of chromosomes normally in the egg but later discarded. Polyploidy (more than two sets of chromosomes) is common in the animal kingdom.

Q: The new sturgeon regulations mandate that only barbless hooks can be used when fishing for sturgeon. Does this mean it is now illegal to use two rods in waters where only barbless hooks are allowed? This doesn't seem right.

— Anonymous

A: No. Establishment of the barbless regulation for sturgeon does not alter use of the second-rod validation (e.g. the 2-rod stamp). The second-rod validation pertains only to specific bodies of water.

Q: I've read about crab fishing using a fishing pole and "crab snares" but don't know what regulations apply. Can you please clarify?

— Tim T.

A: These are called "loop traps" in the regulation booklet. Basically, they are composed of a bait box and up to six monofilament loops used to snare the crab. They are fished at the end of a line. Crab traps — including crab loop traps — can be used north of Point Arguello to take all species of crabs. For taking Dungeness crabs from commercial fishing vessels, refer to the Ocean Sport Fishing regulations booklet. Note: Loop traps can have only up to six loops. You can find many loop traps with more, but they are not legal in California waters; if you buy them, you'll need to cut off any extra loops.

Q: Why am I required to buy a sturgeon fishing report card and tags? What will the collected money be used for? Will the money be directed to a dedicated fund account?

— Anonymous

A: The sturgeon fishing report cards with tags were created to help enforce of the sturgeon bag limit, a key conservation measure. In addition, data from the report cards is valuable for ongoing sturgeon research. The money from the report card will be used to fund increased data analysis of sturgeon populations (white and green) and enforcement of the regulations related to the fishery. Card fees are not going to a dedicated fund because a dedicated fund can only be created by the Legislature.

Carrie Wilson is a marine environmental scientist with the California Department of Fish and Wildlife. Contact her at Cal.Outdoors@wildlife.ca.gov

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