It’s dark outside, and the pre-dawn Monday morning traffic in Baltimore’s Harbor Tunnel is light. I just made a mad dash out of bed, into my truck, and to the ATM and gas station, thinking I’d overslept to make a timely 7 a.m. arrival for my date near Taylor’s Island on Maryland’s Eastern Shore, where I was to jump on a boat with a host of state-employed oyster experts. As I emerge from the tunnel and head toward Interstate 97, I glance at my phone—oh, right, the clocks changed back over the weekend. Knowing I’d be early, I slow down, put on the cruise control, relax to some tunes, and start to think about oysters.

The men I’ll be meeting carry on what they and others have been doing for 75 straight years: conducting Maryland’s annual oyster survey, a running measure of the size and health of Maryland’s wild population of Crassostrea virginica, better known as the Eastern oyster, the only oyster species in the Chesapeake Bay. From aboard the 48-foot, diesel-powered research vessel Miss Kay, they dredge samples of oysters off their colonies, or bars, from the same locations all over the Bay every year, and sort, count, and measure the catch, saving some to take to a lab to study for disease, and putting the rest back overboard. After a few months, the resulting data ends up released and summarized in the widely anticipated “Maryland Oyster Population Status Report.”

When the survey started in 1939, Maryland watermen landed more than three million oysters; in 2013, the commercial harvest was 341,000 oysters—about a tenth of the historic take, but the largest in a dozen years. The survey has yielded good news in recent times, as the incidence of disease among oysters has been low and their survivorship high, though the measure of their reproductive success—the amount of “spat,” or baby oysters growing on shells—has been uneven. The generally positive trend tentatively indicates a depleted fishery on a bit of a mend, a sign that nearly 200 years of regulation of the fishery, and significant modern public investment in recovery efforts, are bearing some fruit.

As Eric Schott, a University of Maryland Center for Environmental Science biologist at University of Maryland Baltimore County’s Institute of Marine and Environmental Technology, told me over the phone recently, the oyster survey is “seeing historically low disease rates with high recruitment rates, and this last year was really a blockbuster,” trends that he attributes to “oyster restoration efforts that are fantastic now.”

I’m hungry and under-caffeinated, but determined not to hit some franchise along Route 50 East. So I hold off as I leave Cambridge, faithful that there will be a stalwart back-roads survivor that serves the locals as I head westward on Route 16, which, as the convenience stores and housing tracts give way to farmland, pine stands, and salt marshes, eventually becomes Taylor’s Island Road.

Sure enough, as the sun starts casting a few dim rays on the tops of the pines, I come across a roadside building that houses both a U.S. Post Office and the Woolford General Store, where a big sign outside advertises kits for growing your own Chesapeake Gold oysters, sold by an aquaculture outfit in nearby Hooper’s Island. This reminds me of a simmering cultural and economic conflict between traditional Maryland watermen, who rely on healthy wild stocks to make their living, and a new breed of science-savvy oyster farmers, whose caged stocks form manufactured reefs on leased stretches of bay bottom. The watermen tend to see the rise in oyster aquaculture as an unsightly threat to their freedom to fish, but the ecological benefit of live oysters, the more the better, is hard to argue against: Each full-grown one can filter many gallons of water a day, helping to cleanse the bay’s polluted waters and thereby boosting the fortunes of all its fisheries.

A couple of dudes in camouflage and wearing muck boots are walking out of the Woolford General Store, carrying coffee and brown bags as they get in their lift-kitted pickups. Inside, munching on bacon-egg-and-cheese-on-ryes and watching the political ads on the local TV station, I note the wares for sale: guns, fishing equipment, beer. I’m less than 10 miles from the strip malls of Cambridge, and only about 90 miles from Baltimore, but places like this remind me how rural much of Maryland is. A rooster crows nearby as I get back in my truck to leave.

Heading west from Woolford, the road crosses the upper reaches of Madison Bay, Woolford Creek, and Parsons Creek, where dead pine trees at the edges of the salt marshes stand as testaments to one of the many changes the Bay’s habitats are undergoing: The intrusion of brackish water from inexorable sea-level rise is killing off the pines at the edges of marshes. A bald eagle lights from one of them as I drive by, and I remember past trips to Taylor’s Island, when, while kayaking, I drifted close by as dozens of eagles feasted on huge rockfish, too busy using their talons to tear apart the fish flesh to be bothered by me. The dead pines apparently make good habitat for hungry eagles, as they can perch atop them and watch for passing fish.

Slaughter Creek Marina, where I’m to meet the oyster-survey team from Maryland’s Department of Natural Resources (DNR), is providing a temporary berth for the Miss Kay, but it’s the permanent home of Palm Beach Willie’s Restaurant and Bar, an unlikely Key West-style party spot in a tiny community that boasts a population of 174. I’m quite early, and totally alone, so I change into my foul-weather gear, sip my coffee, and wait. The Miss Kay is at a slip, basking in the rising sun, amid a spare combination of working boats and yachts that bob in the wind-driven waters of the marina. Finally, right at 7 a.m., a white pickup truck with state-government license plates arrives, and two men get out and walk the pier to the Miss Kay. They seem not to notice me, so I tentatively follow.

“You the reporter?” asks Dave White, the pony-tailed, clean-shaven captain of the Miss Kay. He’s wearing a U.S. Navy cap and khakis and he and his mate, Thomas Wilson, are busying themselves with starting the Miss Kay’s engines, booting up the navigational systems, getting a pot of coffee going, and preparing the deck for a day of work on the water. I try to stay out of the way, feeling very much the landlubber despite my bright-yellow nautical attire.

Soon, the scientific team arrives: leader Mitchell Tarnowski, head of monitoring and assessment for DNR’s Shellfish Division; two biologists who work under him, Robert Bussell and Mark Homer; Chris Judy, the former Shellfish Division director who now runs a DNR citizen-involvement aquaculture program called Marylanders Grow Oysters (MGO); and Steve Schneider, also with MGO. Tarnowski, Homer, and Judy have known one another for nearly a quarter-century, while Bussell’s been around with them for about a decade, and Schneider joined in four or five years ago, Tarnowski explains later, calling Homer the “old guy” and Schneider—the only beardless one of the bunch—the “newbie.” All of them, it becomes apparent over the course of the day, enjoy the kind of in-the-field camaraderie that grows from mutual respect earned over time spent in their common cause: understanding and trying to heal the bay’s struggling wild oysters.

This is “probably the longest-running oyster survey in the country, if not the world,” says Tarnowski, adding that its 75th anniversary makes it “sort of a special year for us.” He also points out that “you came out on a good day,” because “two of the most knowledgeable guys on oysters in Maryland” are on board: Judy and Homer. Judy’s MGO program—which promotes the placement of caged oysters off waterfront property, strictly for their ecological benefits, not for eating—is “going like gangbusters,” Tarnowski explains, and Homer has a Ph.D. and has been “working on oysters for 25 years,” so “you’ve got two guys who really, really know their stuff.”

The men wear hats, put on oilskins, and get work gloves at the ready, for warmth and protection from the cold, wet, dirty work ahead (except for the long-haired Homer, who goes bare-handed and hatless, wearing a green parka over his Orioles T-shirt). Bussell wears nothing on his feet but Teva-style sandals, and, faced with remarks about what must be his remarkable circulatory health, quips that his toes “died years ago.”

“First station’s right out here,” announces  Tarnowski over the roar of Miss Kay’s engines, as he points up Slaughter Creek to an unmarked spot. “All right, let’s get going,” announces White from the helm, and starts to maneuver the vessel out of the marina.

Minutes later, White slows down the Miss Kay as Bussell, Wilson, and Schneider ready the power-dredge rig, which sits on the vessel’s stern and releases the dredge over its starboard aft. The first of the day’s data-gathering rituals is set to begin.

The dredge is a 32-inch-wide heavy-chain basket attached by lines to a powerful hydraulic winch. At 14 locations all over the Little Choptank River during the course of the day, it will be lowered onto the bar below and dragged for a short distance before being winched back up, filled with whatever was in its path. Once hoisted out of the water, the dredge will be guided back aboard, and, as it hovers over a platform fitted on the Miss Kay’s aft deck, Wilson will pull its release lever, causing its bottom to open and its contents to dump onto the platform.

Once a dredged batch of oysters is on the platform, Bussell uses two hands to scoop them into a half-bushel bucket, takes the full bucket to another platform on the port side, just outside the Miss Kay’s cabin, and dumps them out. Now, after buckets of bay water are poured over the oysters to give them a quick cleansing, the sorting, counting, measuring, and inspecting begin in earnest.

Judy, Homer, Schneider, and Bussell dig into the pile of oysters and start calling out things like “two markets,” “small box old,” “oh yeah, gaper, market gaper,” and “market spat,” as they plunk them into metal buckets. They also call out the names of other creatures found in the batch, like “mud crab,” “sponge,” “barnacle,” “mussel,” and the name of a small fish that Homer describes as “beautiful” and explains is “one of the few true reef fish that only live on reefs.” He releases it overboard, saying, “I don’t think he’s going to make it to the bottom, probably get eaten on the way down.” After separating larger from smaller oysters, the men use little plastic rulers to measure their length in millimeters, sounding out a chorus of numbers such as “98, 77, 82, 90,” and “92, 117, 106, 112.”

As his crew calls out their findings, Tarnowski sits nearby with a clipboard and a pencil, madly scribbling on a legal-sized sheet of paper that is printed with boxes, rows, columns, and checklists designed for the survey, turning the chorus of code words and numbers into meaningful data. He has an interesting and efficient way of marking out counts of 10: First he makes four dots, then he connects them with four lines to make a box, and finally he marks an “X” in the middle.

“We look at how many are alive, how many dead, their sizes, and fouling organisms like barnacles and crabs,” Tarnowski explains—as well as large numbers of “sea squirts,” ball-shaped organisms about the size of marbles that cluster around the oysters, and which Tarnowski says “are more closely related to us than they are to the oysters.” Market-sized oysters of 76 millimeters (three inches) or more are called “markets,” while “smalls” are less than market size and “boxes” are dead oysters whose shells have not yet separated from one another, indicating they died relatively recently–though there can be new boxes with clean shells inside and old boxes, which tend have things living in them. A “gaper,” Homer explains, is “a dead oyster that still has meat in it. You don’t want to smell it, very disgusting.”

Thus, an endemic oyster culture infuses the whole enterprise, as the terminology, Schneider explains, is specific to the survey, while the oyster bars sampled have names such as Cason, Ragged Point, Butter Pot, and Grapevine, says Tarnowski, that arose from age-old local traditions.

The oyster-eating tradition, though, is not universally shared by the survey crew. Judy, who opened up a couple for close examination over the course of the day, only likes them cooked, but Schneider happily slurps a raw one down, and recalls long-ago days in Louisiana when he could get them so cheap “you could make a meal out of them for less than 10 bucks, beer included. It’ll never be like that again.” They all seemed to like my description of a P.S. Mueller line-drawing cartoon I’ve always remembered, though, in which a man holds an oyster on the half shell, and the thought-balloon over the man says, “I wonder if it’s alive,” and the one over the oyster says, “I wonder if he’ll chew.”

After finishing up the tally at the Slaughter Creek site, White throttles up the Miss Kay and heads up the Little Choptank River toward the Cason bar, passing two large barges on the way, one bearing a crane and the other filled with fossilized oyster shells brought up from Florida. These are part of an ongoing, high-dollar effort by DNR to construct hundreds of acres of oyster reefs in the Little Choptank and two other tributaries, Harris Creek and the Tred Avon River, and all told the price tag could come to more than $70 million. At one of the Little Choptank sites the Miss Kay crew visits, fossilized oyster shells came up in the dredge, along with “marl,” the calcium-carbonate substrate in which the oyster fossils were embedded.

Local officials have questioned the oyster-reef projects, worrying that its potential future benefits come at the expense of current fishing. But perhaps a more fundamental issue is whether the Little Choptank and its tributaries, which are showing signs of a natural rebound thanks to being oyster sanctuaries where harvesting has been banned since 2010, are appropriate sites for reef-building, rather than other places where oyster populations have collapsed. I make the point that unproven investments made in places where success is likely, should they succeed, will enhance the public’s willingness to make similar investments elsewhere in places that have greater need. Tarnowski agrees, saying later that “other people have other opinions, but it makes more sense to get the momentum going to prove the concept, so we can get to the other areas that need it.”

Once at the Cason bar, a slight controversy comes aboard with the dredged catch: “hatchery spat,” they call it. Over about 1,600 acres of Bay bottom, the nonprofit Oyster Recovery Partnership (ORP) has planted about five billion baby oysters on shells, after they’ve been raised from seeds at the Horn Point Laboratory’s hatchery at the University of Maryland Center for Environmental Science’s campus in Cambridge. The ORP’s efforts have been quite successful—monitoring reports by University of Maryland’s Paynter Laboratory found survivorship among ORP’s planted spat to average around 35 percent over the past few years, much higher than in years previous—but an apparent breakdown in coordination between ORP and DNR’s survey team has resulted in hatchery spat being planted on part of the Cason bar.

“Generally speaking, it hasn’t been that much of a problem,” Tarnowski explains later, “but I was surprised that it was on Cason that they planted, because that’s one of our main bars.” The difference between natural spat and hatchery spat is easily spotted: “Hatchery spat tend to be clustered in large numbers,” he explains later, “and you can also tell by the shells, which are from shucking houses, so they have nicks on them. There are one or two oysters per shell in natural spat.” The issue can be cleared up, he says, with “a meeting of the brain trust” to avoid ORP planting on bars that are part of DNR’s annual survey. “In the beginning of the year, they just need to say ‘we’re going to plant here, here, and here,’” he concludes.

Another sample is taken at another part of the Cason, untainted by hatchery spat, and, after the sorting, counting, and measuring, Tarnowski is enthused, saying, “that’s a nice haul.” Overall, he says, the day’s survey is showing about 250 market-sized oysters per bushel dredged, and a bushel sold usually contains about 350 oysters, “so we can say roughly two-thirds is just oysters, and that’s very nice, so this river’s doing good. It’s coming back all on its own.”

Two years ago, Tarnowski continues, “we got a lot of spat, and we can see that they’ve grown up,” though “they’re not reproducing” like they did in 2012 and 2010. “Recruitment—that is spat set—was poorer than in previous years, but there’s very good survivorship, not many boxes,” he adds, and that’s “very encouraging” given that “this is a river where there was 92-percent mortality 12 years ago” due to disease.

Back in the Miss Kay’s cabin, while en route between locations, the conversation among these professional oyster counters tends toward the jocular and trivial. Killing time is an art form, and among these guys, with their long histories together, it’s been perfected.

Tarnowski asks who recorded the most popular version of Donovan’s song ‘Season of the Witch,’ and eventually gives up the answer: Steve Stills and Al Kooper on their “Super Sessions” release, and Homer points out that Jimmy Page played guitar on the original. They work out that the H.L. Mencken-inspired character in the movie version of “Inherit the Wind,” about the Scopes monkey trial, was played by Gene Kelly, that Stills’ accordion made a cameo in the Ridley Scott movie “Prometheus,” and that it’s strange that there are many people named “Viola,” but probably none named “Violin.” Tarnowski is a huge Joseph Mitchell fan, given the writer’s detailed journalistic treatments of marine-biology subjects, including oysters, while Bussell and Homer proudly recollect their work on a short video about the precipitous collapse of Maryland’s razor-clam population, a prized bait-fishery for crabbers, and especially reminisce on their creative use of music in it, including snippets from Pink Floyd’s “Wish You Were Here.” I contribute my bit about how I once caught my very pretty cat carrying on amorously with a baby rat, and that it turns out there’s a scientific explanation for such oddball behavior on the part of the rat—but not the cat, who’s just incredibly dumb.

As the day wears on, the breeze eases and the temperature rises with the sun. At the mouth of the Little Choptank, James Island is visible, a shrinking, sinking island whose contours I mapped by kayak in 2007 and 2013, using a handheld GPS, showing it had lost 67 percent of its acreage in six years. It looks like it’s lost even more in the past year, as has the farm on Oyster Cove on the northwest tip of Taylor’s Island whose fields have been falling into the Bay in huge chunks, once again reminding me how real sea-level rise is. Nearby, divers are collecting oysters from the bottom, working off of two boats outside the sanctuary boundaries, and Judy remarks on the incredible dangers they face. As for the dangers the bay faces, Judy says he’s “an optimist. You got to just keep grinding and working, and there are setbacks, but hopefully we can get the job done.”

The oyster-recovery job has really only just begun, despite generations of earlier efforts. The U.S. Army Corps of Engineers has been working on it for the last 15 or 20 years, but its coordinated master plan for Maryland and Virginia, the latest draft of which was put out in 2012, calls for restoring 20 to 40 percent of the bay’s historic oyster habitat and protecting it as sanctuary. The cost, covering about 20,000 to 40,000 acres of habitat restoration in 19 targeted tributaries, is estimated to range from $2 to $8 billion. Citing scientific literature to provide a baseline for the hoped-for rebound, the Corps says the bay’s oyster abundance has dropped 92 percent since 1980, and 70 percent of its habitat has been lost in that time. It’s a big, big project, but it’s now begun: The Chesapeake Bay Watershed Agreement, signed in June this year, calls for 10 reef-building projects like the ones in the Little Choptank to be completed by 2025.

The Miss Kay heads back to the Slaughter Creek Marina, and I jump ship, as do Bussell and Homer. The rest, though, head back out to do a few more dredges on their way to Oxford, where they’ll drop off the bags of oysters they saved for lab work at the Cooperative Oxford Laboratory, an oyster-studying facility run jointly by DNR and the federal government, to see if they are suffering from any diseases.

Though it’s too soon to say that setting up sanctuaries, planting hatchery spat, and building new reefs are actually leading to a self-sustaining and rebounding oyster population, what’s known so far about this year’s oyster survey—that, as Tarnowski puts it, “we’re still seeing good survivorship, but not much spat set”—indicates that it’s another decent showing, especially if the disease work, which won’t be completed for another couple of months, continues to show a healthy population.

Three days later, I talk to Tarnowski over the phone, and he’s again enthused at what the survey is showing. “We had a shit-load of oysters today on Harris Creek,” he says, “and also on Broad Creek, which is open to harvesting, including dredging. And on one bar at the mouth of Harris Creek, we saw 28 boats dredging.” Thus, what’s shaping up to be another good year for DNR’s oyster counters may also be another banner season for the watermen. And you know what that means: more Chesapeake Bay oysters to eat.