Mysterious fall migration of striped bass in Connecticut Rivers
This article is a year old, originally published in the NY Times, but thought some folks might find it interesting.
Trying to Solve Mysteries of Striped Bass in Winter
By JOHN WALDMAN
Published: April 7, 2007
Fishermen and scientists may never fully understand the striped bass, but they will never stop trying. Few fish have been studied as much as the striped bass has between spring and fall. Its wintering biology, however, is less understood.
Skip to next paragraph http://graphics8.nytimes.com/images/...tdoors_MAP.jpg The New York Times
Stripers can be found in several Connecticut rivers in winter.
During autumn, stripers entertain anglers as they migrate south from New England. Large individuals then winter in ocean waters, but many of their smaller counterparts, known as schoolies, travel to major estuaries that support striped bass spawning, namely the Hudson and Delaware Rivers and the Chesapeake Bay.
Some, however, ride out the cold months in systems where they do not reproduce, including the Housatonic and Connecticut Rivers in Connecticut and Scortons Creek on Cape Cod. Judging from fishermen’s catches, none of these hold anywhere near the sheer numbers of the upper Thames River in Connecticut, home to an unusual aggregation of wintering striped bass long known to fishermen but not to scientists.
Mike Bednarski, a Queens College graduate student and an avid angler, tried to tackle this striped bass riddle.
In December, he placed ultrasonic transmitters in seven stripers to use remote sensing to chart their movements in relation to changing conditions. A couple months later, on the second day of a midwinter thaw, we could sense spring uncoiling from winter’s grip when we met at the town dock in Norwich, Conn.
After idling through the fishing fleet, we ran five miles downriver among ice sheets — spooking two bald eagles off a floe — to test temperatures and salinities in the same reach of river where Bednarski had located the southern end of a great striper school in early January, before the freeze began. The sonar fish finder did not mark any striped bass at this destination, so we headed back to Norwich Harbor to sample the fishing. There, the fish finder showed a solid mass of stripers under the boat, but we caught only one in half an hour.
Nearby, three men were gleefully landing one fish after another. Asked what they were doing right, one said that, because most of the stripers were swimming at a depth of about 20 feet, they were dropping their lures to 17 feet and gently teasing the fish upward. He handed us a couple of the jigs they were using. Even then, we struggled to work the lures with the correct action and landed only a few while the other men were at times fighting three schoolies at once.
Because this fishing sometimes occurs under brutal conditions and requires a degree of skill, its practitioners tend to be dedicated. We noticed partners in one boat marking stripers with tags from the American Littoral Society to learn where their catches went after they left the river in spring. Most appear to originate from the Hudson, the nearest river where stripers spawn.
Bednarski also wanted to capture the striper schools on videotape, so he lowered an underwater camera. The water was murky, but when the rig hit the magical 20-foot level, we saw stripers moving past the lens.
The final task was to find the seven stripers that Bednarski had tagged with transmitters in December. He slipped on the receiver’s headphones, dialed to the frequency of one striper, submerged the listening cone and rotated it to determine the direction of the strongest signal. The river was surprisingly noisy; Bednarski could hear the hammering of other anglers’ fish finders and even interference from someone else’s ultrasonic transmitter.
He teased out the pinging sound from striped bass No. 1 and, after two more location adjustments with the boat, zeroed in on the fish. To document the conditions that the fish preferred, Bednarski conducted a series of temperature and salinity measurements at regular depth intervals near the striper’s position.
While he recorded his data, I watched two men troll and land striper after striper. By now I had come to realize that the abundance of striped bass in this stretch of the river was staggering. As the trollers neared us, Bednarski shouted, “How many are you up to?”
The reply: “107.” And they were not done yet.
We located all seven striped bass before nightfall, and all told the same story. The five-mile long body of stripers seen in December had contracted to become a dense aggregation at the head of the estuary. The surface waters were fresh and frigid, carrying ice chunks from the two rivers — the Yantic and Shetucket — that feed the main stem Thames. But beneath this inhospitable layer was a tongue of the sea — 42-degree, full-strength salt water, slightly warmer than what we measured downriver, and phenomenally attractive to a not insignificant portion of the Atlantic coast migratory striped bass stock.
When we finished and motored toward the dock, I thought that, considering how hard it is to locate this species for so much of the year, it was extraordinary to know at this moment exactly where these seven stripers were holding, with untold numbers of their brethren alongside them. But I also noted with pleasure that in a few weeks, as winter yielded to spring, these particular fish would disappear back into the vastness of the sea, trailing plenty of other mysteries behind them.
Striped bass: Atlantic Coast Diadromous Fish Habitat
There is some older research here which supports the migration and possible spawning. On page 262 they talk about the CT rivers. On page 260 they say the biggest % of fry down south comes from the Susquehanna River. Interesting stuff.
http://www.friendsofmerrymeetingbay....at_2009_10.pdf
Re: Mysterious fall migration of striped bass in Connecticut Rivers
Quote:
Originally Posted by
dogfish
If netters or fishermen take too many out of one population, that single population will suffer more than the others.
Excellent point dogfish.
