It would be a quiet and peaceful morning at the edge of the Choptank River in Cambridge, Maryland, if not for the forklifts racing around the pier, scraping five-foot-tall metal cages along the ground as they go. It’s early May and the sun is just beginning to burn off the mid-morning haze, but the crew has been at it since dawn. Everyone is energized despite the early start, and rightfully so, because the cages are brimming with oysters bound for a new home. This is the biggest day of reef restoration the Chesapeake Bay has ever seen.  A cage full of baby oysters bound for the Manokin River. Credit: Ben Seal A crane lifts the cages out of eight tanks submerged into the river, where millions of baby oysters — spat, as they’re known — have spent the past week searching for the right shell. One by one, 200 in all, the cages are dragged over to a conveyor belt and dumped out in a sudden clamor. Up the belt they climb as they’re loaded onto the J. Millard Tawes for transport. The vessel served as an icebreaker and buoy tender in its past lives, but today it will carry these mollusks south for 70 nautical miles to the Manokin River, where they’ll get to work breathing life back into the bay.   In the early 1900s, spent oyster shells were piled high at shucking houses throughout this region. Each one represented a piece of reef removed, rapidly degrading the aquatic environment in the process. In the Maryland portion of the bay alone, an estimated 15 million bushels were harvested annually to satisfy demand. With a helping hand from nutrient pollution and two ravaging mid-century diseases, excessive harvests decimated the oyster population and the natural habitat formed by the bivalves. By 2011, the population in the bay was estimated at less than one percent of historic levels.  The oysters travel up a conveyor belt on their way to the J. Millard Tawes. Credit: Ben Seal The mountain of shells forming today on the deck of the J. Millard Tawes might resemble the heaps discarded at oyster bars a century ago, but its purpose is to reverse that complicated history. The decade-long, $100 million initiative, led by the National Oceanic and Atmospheric Administration and slated for completion this year, is the world’s largest oyster reef restoration. It serves as a global model — the “gold standard,” according to Olivia Caretti, the coastal restoration program manager for the Oyster Recovery Partnership, a nonprofit leading the conservation of native oysters in the Chesapeake. This morning, she’s ensuring that all these oysters safely complete their journey, which began in March when they were spawned at the nearby Horn Point Oyster Hatchery and will end when they settle onto reefs in the waters of the Manokin.  Weighed down by negative news? Our smart, bright, weekly newsletter is the uplift you’ve been looking for. [contact-form-7] The river is one of 10 Chesapeake tributaries targeted by the project, and its 450 acres of restored reef alone would surpass any other undertaking. Today, 23 million spat will be planted into the river to join the cause. The ship sags under their weight, enough that its captain briefly wonders if it’s hit bottom. It’s the team’s largest planting to date, and donuts are in order as part of the celebration.  Once an icebreaker, the J. Millard Tawes now transports oysters. Credit: Ben Seal “In this era of climate change and environmental degradation, this is a rare success story,” says Stephanie Westby, NOAA’s oyster reef program manager. “We have 1,700 or so acres of healthy oyster reefs that just weren’t there before.” For most of human history, the Chesapeake Bay, America’s largest estuary, was a thriving aquatic ecosystem and oysters were a keystone species. In the colonial era, they were reportedly so abundant that their reefs pressed up toward the water’s surface, posing a navigational hazard for ships passing through the bay. For centuries, all those oysters supported the bay’s health through their very nature.  Baby oysters, known as spat. Credit: Ben Seal By filtering water, the oysters allowed underwater grasses to absorb the sunlight they needed to flourish, offering habitat to countless fish and the bay’s beloved blue crabs. By eating microscopic plankton, they played a pivotal role in the food web, amassing energy that could be passed on to other marine life. By drawing nitrogen and phosphorus out of the water column, they helped prevent algae blooms and the hypoxic dead zones that sometimes follow in their wake. And by conglomerating into reefs, they brought stability and welcome habitat for their neighbors in the bay. For a long time, efforts to revive those valuable contributions to ecosystem health were “scattershot,” Westby says. It was “a half-acre here or there, maybe two or three if we were really rocking it.” When the Obama administration issued an executive order in 2009 targeting the bay’s protection and restoration, it was a “sea change,” she says. The collaboration among state and federal agencies, scientists and environmental organizations shifted into a higher gear. In 2014, the Chesapeake Bay Watershed Agreement created a regional compact to restore 10 tributaries by 2025.