“Can you tell me about sturgeon sex?”
My question hangs in the air for a second, time enough for Matt Balazik, PhD, to consider whether I might be kidding — or setting him up for another round of fish jokes that have peppered the banter during the early October afternoon aboard the 27-foot research skiff.
I am as serious as a growing child who wants to assemble the mass of clues she’s gathered into a coherent picture to answer where babies come from. But I want to know how baby sturgeon come to be in this stretch of the James off Presque Isle, just outside the channel where ocean-going tugs come and go from the port of Richmond some 15 miles upstream.
Balazik has a ready answer, as he and his crew, Jamie Brunkow, lower James Riverkeeper, continue to hand-over-hand the nylon mesh gill net up and across the deck and back down into the tidal water that is so far upstream from the mouth of the Bay that it rarely measures more than 1 or 2 parts per millions in salinity.
“The males congregate in the water along this part of the river, near where the bottom is good. It’s kind of like a staging area, where they wait for the female, who is ready to spawn,” explains Balazik.
“And when she comes by, they follow her. She’s looking for the right kind of bottom, a place she somehow knows is just right. Depending on size, she’s got as many as 40 or 50 pounds of eggs ready to release.”
Both male and female sturgeon know this stretch of the James as their home, the place where at least 10 years earlier their lives began in a similar ritual — before, as young fish, they swam to the coast and a life in the open waters of the Atlantic.
Balazik, who has been studying sturgeon through a masters and doctorate at Virginia Commonwealth University using its Rice Center as a base of operations, explains that the males literally jockey for position to be immediately under and behind the female when she starts to release her eggs, up to 2 million in one spawn. They, too, are ready, spraying their milt into the water where chance and natural selection guide this watery dance of reproduction.
As Balazik and Brunkow haul the net, our boat is drawn across the bottom, with help from Chuck Frederickson at the control console, jogging the boat ever so slightly towards the flag buoy at the other end of the net.
Frederickson is the former Lower James Riverkeeper, recently retired but out here now on his own time because it’s hard to resist the opportunity to see the sturgeon up close and personal. In the late 1990s, Frederickson, then working for the James River Association, was part of a team that included conservationists, corporations, and scientists that wanted the see the return of the sturgeon, which were once thought to have been extirpated from this section of their historic spawning grounds.
Balazik continues talking while he watches the angle of our boat to the net, his body poised to sense the change in the weight of the haul. It’s a particular kind of drag that is caused by a sturgeon caught cross-wise in the net.
This season, he has caught more than 130 sturgeon in nets along this stretch of river. Balazik has placed egg mats strategically in spawning areas, hauling them periodically in hopes of finding eggs. He’s played host to a growing number of water managers, agency scientists, and representatives from the press now that he’s demonstrated for science that the autumn spawning — once known to local fishermen but never quite believed — is for real.
The previous 200-foot long net yielded two sturgeon, which are now resting belly up in a long trough filled with river water constantly being refreshed by a pump in the stern of the boat. Balazik will tag, measure, and release them back to the river. He will also take blood samples to check, among other things, the levels of testosterone as an indicator of how “ready” these males are to spawn, and also take tissue samples for DNA analysis.
I’ve inspected these fish, peeking under the blue tarp laid over them to keep the sun off, watching as their toothless mouths pull in water to pass over their blood red gills. Both fish show definite signs of “scrapes” — bruised and red undersides that tell of the underwater struggle to maintain the optimum position below the female as she prepares to release her eggs.
The sturgeon’s skeletal support is external, made up of rows of larger, interlocking plates called scutes that run lengthwise down the fish. They are hard and sharp, and scientists believe it is scute-to-scute rubbing between the male fish — and possibly between male and female — that causes the bruising so evident when they are caught during the spawning run.
So the answer to my question, simply put, is that sturgeon sex is rough.
We reach the end of this net, and Balazik turns to the two fish in the tank, measuring each in turn, while Brunkow records on the data sheet. To determine the age requires lab work, but Balazik has handled enough fish and enough data over the last eight years that he can make an educated guess of 10 or 11 years for the smaller one, 14 to 16 for the larger one.
Data gathered, Balazik kneels to raise the fish out of the tank water, gathering it to his chest in an intimate hug for the short trip across the deck and the unavoidably awkward toss back into the river. The torpedo-shaped fish disappears immediately into the murky water.
The fertilized eggs of the sturgeon are coated with a sticky substance designed to fix them on the substrate during the larval stages of growth. For this reason, rocky bottom is preferable to mud, and we all wonder – aloud and to ourselves – about the future of sturgeon in this river, awash with silt from the Piedmont and the muddy banks along this tidal stretch of the river.
It may be another 10 to 15 years before the progeny of these sturgeon tagged in 2013 return for the bump and scrape of sexual reproduction on the bottom of this river. By that time, Balazik and other scientists studying these grand and ancient fish, will know more about their habits, sexual and otherwise. And the James River, we hope, will be that much cleaner.