This should be high shad-fishing season on the Potomac River. The weather is right, the air is warm and moist, the river is running clear.

Everything is as it should be except for one small thing. No shad.

Only a few, at best.

Time was, even as recently as eight or 10 years ago, that a Washington shad fisherman could expect to catch 20 or even 30 white shad on a spring foray if he picked the right day.

In 1980, the absolute best shad fishermen in the Nation's Capital would be more than satisfied to catch 30 in a season.

Where have the shad gone?

To understand the precipitous decline or white shad in Washington's river it helps to understand the fish. Shad are anadromous, which means they live in the sea but return to freshwater rivers to reproduce.

Oddly, they are imprinted at birth with the knowledge of their "home river." They will stay in the river through their first summer of life, growing to a size of about 2 1/2 inches before leaving in the fall for the ocean.

Most return only once, above five years later, to the place where they were hatched. There they deposit eggs for the next generation. Somewhere the system has broken down in the Potomac and other big Chesapeake Bay feeder rivers.

Last month Maryland, responding to disastrous slumps in the number of shad caught in its portions of the Chesapeake and its tributaries, closed the season on white shad to both commerical and sport fishing. The Maryland shad catch has dropped from almost 600,000 pounds in 1973 to 20,000 pounds in 1979.

The regulation does not apply to the Potomac, whose tidal stretches are regulated by the Potomac River Fisheries Commission.But the PRFC is seeking a similar ban to go into effect before next years's spring run.

It all seems rather moot anyway, because almost no one fishes commercially for the few remaining shad in Maryland anymore, and sport fishermen are so thrilled to catch one these days that they're as likely as not to put it back alive in the hope it will spawn a new generation.

Maryland-born shad are victims, according to the people who are watching them, of three wrongs -- changes in river water quality and spawning areas; overfishing; and blockage of upstream migration routes by dams.

In the Potomac, the dams don't seem a major problem. The fatherest-downstream dam is at Little Falls, which cuts off only about 10 miles of river between it and nature's huge dam, Great Falls.

But declining water quality, disappearing spawning grounds and over-fishing likely have done their damage.

"What we suspect most," said Bob Norris, executive secretary of the Potomac River Fisheries Commission, "is chemical pollution, plus the destruction of spawning grounds."

Surprisingly, the chemical pollution he suspects is the very same stuff that has Washingtonians bragging about how lovely the river is now, compared to 10 years ago.


The construction and expansion of sewage-treatment plants for municipalities along the length of the Potomac has helped the river rebound from the days when summer meant a sea of thick green algae blooms.

"You can make the water biologically clean as far as algal growth," said Norris, "but that's not making it chemically clean."

Chlorine is a biocide, and a strong enough dose of it can make the water pretty by making it sterile, like a swimming pool.

"It kills germs and anything that kills germs kills things like oyster larvae and fish larvae," said Norris. "We found that out in a study on the James River, where we had chlorine overflows."

Add to that the destruction of spawning habitat by dredging for sand and gravel, which Norris said was big business in the river below Washington until about 10 years ago. Shad spawn over sand and gravel.

Then add the channelization ans siltation of feeder creeks and streams running through newly developed land and into the river and you have a mess as far as shad are concerned.

Because these fish are turned to their home rivers, a decline in sahd in the Potomac and the upper Chesapeake doesn't necessarily mean a disaster for the species as a whole. There were tons and tons of shad and shad roe for sale this spring in Washington-area stores, mostly shad from Virginia, Delaware, New York and North Carolina, where they are doing well as they reproduce in less urbanized rivers.

The Rappahannock River enjoyed one of its better shad runs this year, according to sport fishermen there. "I've eaten so much white shad roe I can't stand another bite," said Reggie Chesley of Fredericksburg.

In Washington it's not so happy a scene.

Extinction? "As far as the Potomac and the upper Chesapeake are concerned, I think it's not only possile but likely at the rate we're going," said Norris.