The plan was for folks to descend on du Pont Co.'s 3,300-acre Remington Farms last week to watch two young bald eagles, which had hatched two months earlier in the top of a tall tree, get wired for sound.

Young men were supposed to scale the tree and bring the eagles down so scientists from Virginia Polytechnic Institute could strap solar-powered beepers on their backs.

But when the principals convened a few days early for a test run, they found the eagles were just about too big to fool with. "We were afraid if we waited until everyone got here, we might have a jumper, so we went ahead and wired them up," said du Pont spokesman J.P. Smith.

A jumping eaglet is no pretty sight, according to Keith Cline, who climbs trees to band young eagles for the National Wildlife Federation. Cline said a 10-pound eagle that can't quite fly can sound like a cinderblock coming down from the treetops, although Cline said he has yet to see a jumper get hurt in a fall. "When they get about eight or nine weeks old they get nervous and agitated," he said. "Sometimes when you get there, they just jump."

Anyway, nobody wanted a scene, not in front of Interior Secretary Donald Hodel and his assistant for fish and wildlife, Bill Horn, not to mention the TV cameras and the chairman of du Pont, Dick Heckert. So instead of trooping out in the woods after wild eagles, the Reagan administration brought its own eagle, a 9-week-old fresh from the hatchery at Patuxent Wildlife Research Center.

Jim Carpenter of the eagle propagation program trotted the youngster out into the sunshine and the photographers went wild. Carpenter clamped the talons in one hand and draped his other arm across the bird's chest as if to restrain it from attacking. The bird looked huge, a feathered medicine ball with a hooked beak. It was a mess.

The big bird's feathers were greasy and mussed, it was shedding white particles like oversized dandruff and it had a look of hollow terror in its eyes. "Looks like something somebody used in a pillow fight," said Hodel, picking feathers off his shirt.

The purpose of all the gaiety was to clap du Pont on the back for donating, for the fourth straight year, $50,000 to the government's eagle propagation program, through which some 90 hatchery-reared eaglets have been loosed in the wild over the last 10 years.

The government plants eagles in states where there are none, or few, in an effort to stimulate expansion of the national bird's range. But the question is, if you put an eagle out in Tennessee, in an area where there aren't any other eagles, where does it find a mate to propagate with?

"Eagle bars," said Carpenter.

Actually, he said, eagles naturally converge during their migrations at environmental "hot spots," including several in the Chesapeake Bay region, where they woo their mates-for-life. Sounds like an eagle bar to me.

Environmentalists at the Remington Farms bash said bald eagles are doing well these days after the government in 1972 banned use of the pesticide DDT, which nearly wiped the national bird out by decimating its reproductive success. Last winter the National Wildlife Federation counted 11,000 to 13,000 bald eagles in the lower 48 states, and 135 nesting pairs in the Chesapeake region this year, about double the number during the worst DDT years.

So if eagles are doing so well, how come they're still on the endangered list?

The answer, although nobody will go on the record saying it, apparently is that they're good box office. It's a lot easier to draw a crowd of newshounds and the Interior Secretary to Remington Farms to ogle wild or even pen-reared eagles than to get them to chase around some sleepy backwater after a black-footed ferret or Hawaiian crow.

And what's the chance du Pont would donate $200,000 for restoration of ivory-billed woodpeckers?

Some critics think the government is piddling around with eagles, whose population is not only stabilized but growing, when it ought to be concentrating on species truly in danger of extinction, of which there are many.

Strolling through the woods at Remington after an unsuccessful attempt to sight the two young wild eagles in their nest, I asked Hodel if he'd given any thought to that. "No, I haven't," he said, amiably. "Maybe I should have, but I haven't."

Hodel said Interior will help eagles as long as they are officially classified as endangered. He said many benefits accrue from the eagle propagation program, which he said draws attention to habitat protection for endangered species in general. He said propagation and transplanting techniques learned in eagle work can be applied elsewhere.

Whether spending $500,000 a year, the estimated cost of federal, state and private eagle restoration projects, makes sense for a species that is busy restoring itself is another matter.

I remember standing on a dock at the Washington Sailing Marina last summer, in sight of National Airport, and watching an immature bald eagle soar out of the Washington skyline, headed south toward the popular nesting area at Mason Neck, Va.

I said to myself then, and still wonder: "This is an endangered species?"