It gave a final kick of the tail and disappeared into the calm water of San Pablo Bay. This white sturgeon was not yet mature enough to spawn. It would spend several years cruising around San Pablo, Suisun, and San Francisco bays, sucking up clams with its vacuum-like mouth and crushing their shells with its muscular gizzard. All that time, the transmitter I placed inside it would ping its unique coded number, which would be detected by acoustic receivers our Biotelemetry Lab fixed on weight plates or bridge abutments from the Golden Gate Bridge all the way up the Sacramento River.
We would know every time this fish passed Alcatraz or under the Bay Bridge. We would know when it made the migration up the Sacramento River to spawn and when it would decide conditions were right to spawn again years later. It was one of more than green and white sturgeon we tracked for six years for my Ph. Our study , published recently in the journal Environmental Biology of Fishes , is the most comprehensive description yet of green and white sturgeon in the San Francisco Estuary and Sacramento River.
Adult green sturgeon can grow to be 8 feet or longer. Emily Miller. We learned that green sturgeon make long-distance migrations about once every three years to spawn. White sturgeon make their shorter journey nearly every year. We learned that the journey to spawn is exhausting.
Despite most green sturgeon moving quickly through the freshwater system to get back to their marine feeding grounds, about 5 percent of migrating green sturgeon took more than days to recover from spawning. They hunkered in deep river holes. It was previously thought that they did not eat at all when in freshwater. Now we think that cannot be true. Green sturgeon are considered the most marine of all sturgeon, so it is important to understand how they use freshwater. Understanding these two species better, and where they are when, is valuable for agencies working to minimize human disturbances to sturgeon during activities like channel dredging and levee repairs.
If too much water is extracted from the system or released at an unnatural time of year, like the summer, there will not be the right cues for sturgeon to successfully migrate. There also would not be enough healthy clams, crustaceans and fish to support their massive bodies, and we would see their populations drop. Luckily, state and federal agencies monitor sturgeon populations and can use science-based management to ensure their persistence amid competing interests.
Bait and Tackle : Caught with heavy tackle, a sliding bait leader, and live bait such as ghost, mud, or grass shrimp. Large Kahle hooks can be used and several shrimp can be impaled on the hook.
When herring are spawning in nearby areas, herring and herring eggs make excellent bait. Use eel when crabs are are in full force and grabbing softer bait.
Am told the best way to use the eel is to cut off a inch-long chunk. Then cut the chunk into four strips before attaching to the hook. The strips will flutter and hopefully attract Mr. Surprisingly, given their size and manner of sucking in food, sturgeon have a very gentle bite that is hard to detect. Food Value : Excellent, mild-flavored meat that is dense with very small flakes.
Sturgeon contain no bones and cut up nicely into steaks for broiling, baking or frying. The meat does hve relatively high fat content. Comments : Many sturgeon are hooked from Bay Area piers but hooking them is just part of the battle. However, large sturgeon are indeed landed: George Gano landed a pound, eight-foot-long sturgeon while fishing from the old Vallejo Pier and a pound fish was reported from the McNear Park Pier.
Robert aka Red Fish with a sturgeon from the Eckley Pier. Philosopher fish? Sturgeon are considered very special fish by many people. And while females may spawn more than once it occurs only about every 4 to 10 years. Over fishing often illegal poaching in many areas of the world has led to an alarming decrease in the number of females and juvenile fish. For all of these reasons sturgeon rank high in the hierarchy of piscatorial species as seen in the following:.
One thinks of the sturgeon as a kind of philosopher among fishes, as if its ancient lineage had bred, over the thousands of centuries, a curious old wisdom and a quiet acceptance of change. The sturgeon has seen more years when it first spawns than many fish see in a lifetime. Some big white sturgeon from piers —. The Sturgeon Chronicles. Large Sturgeon. The fish in its entirety weighed pounds, and the head as it lies on the block weighs 94 pounds. It is a hideous frontispiece, the gape of its mouth stretching 22 inches from corner to corner, and the space across the back of its head being 28 inches at its broadest expansion.
Were the sturgeon so inclined, being alive and in its native element, it could easily swallow the head of a man, and if his shoulders were not too broad might possibly stow the greater portion of him in his hold, as he measured 10 feet from snout to tail.
This sturgeon which is a genuine Acipenser Oxyrhnchus, was captured by Italian fishermen at the mouth of the Sacramento river in the shoal water where his efforts to escape from the nets were hampered by the shoal water. As it was, he broke the net as if it had been a fly-catcher, and broke three ribs of the boat with his lash.
Commercial fishing for sturgeon in the Bay Area boomed in the s, but by stocks were depleted, and commercial take has been banned in California since In the southern population of green sturgeon, which spawns in the Sacramento River and other rivers south of the Eel, was federally listed as threatened and all fishing was banned. Like other native fish that migrate through the Delta and Bay, sturgeon have suffered from habitat loss and degradation, exclusion from spawning areas, reduced freshwater flows due to dams and water diversions, and depressed populations of prey fish.
International demand for caviar has fueled poaching and a black-market trade for sturgeon worldwide. In fall of , recognition of the imperiled status of green sturgeon led to the designation of critical coastal habitat from Monterey to the Straits of Juan de Fuca, including the San Francisco estuary. Farmed white sturgeon caviar from California is a legal premium product that may help reduce the demand for wild poached caviar, particularly in conjunction with recent efforts by wildlife officials to break up several caviar poaching rings.
Perhaps our growing understanding of these large fish will help us make wiser management decisions to ensure that these ancient wonders from the age of the hadrosaurs will be swimming in our midst for aeons to come. Joseph Kinyon is a geographic information systems and biodiversity database professional who is quite fond of tide pools, carnivorous plants, field journals, and words like petrichor.
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