Roselmino Benvenuti shows the underside of a blue crab with eggs. Luigi Avantaggiato for The Washington Post

VENICE — Last summer, while sweating my way through the Rialto fish market, I spotted a familiar sight from my North Carolina upbringing: Atlantic blue crabs, labeled “granchio blu.” My Italian is not great, but I know gastronomy words and a blue crab when I see one.

As it turns out, the crabs had probably crossed the Atlantic as stowaways in the ballast water on barge ships, and they were first spotted in 2012 in Spain’s Ebro Delta on the Mediterranean Sea. The crab’s excessive increase is a direct result of climate-change-induced sea-level rise and extreme heat in the summer. According to the Maryland Department of Natural Resources, female blue crabs produce up to 8 million eggs a year, and in Venice’s lagoon, they’ve became unstoppable, disrupting the ecology – and economy.

Just as tourists overcrowd hyped vacation destinations in Italy, the blue crabs have become an invasive species, particularly in the Veneto region because its bay hosts no known predators. The crabs prey on young clams, mussels and oysters, and have destroyed up to 90 percent of the area’s young clams, causing severe damage to future production. This invasion prompted the Italian government to allocate 2.9 million euros (about $3.2 million) to protect local fisheries from the crabs. The damage is extraordinary, not only to the marine ecosystem but to small fisherman families whose livelihood depends on providing local shellfish to markets and restaurants.

The invasion also stands to change the region’s culinary culture. “In Venetian cuisine, we have always been used to cooking various types of crabs,” says Denis Begiqi, head chef of Ristorante Adriatica inside Il Palazzo Experimental hotel in Venice. He mentions granseola (spider crab), “with which we make excellent pasta dishes,” and moeche, a tiny soft-shell crab caught in spring and October when the crabs are molting. The latter are fried for a classic Venetian preparation.

Massimo Genari, center, and Porumbel Gennari, right, collect clams by sifting the seabed in Sacca di Goro. They collect the invasive blue crabs as they go. Luigi Avantaggiato for The Washington Post

Many chefs in the region worry that blue crabs could completely overtake marine ecosystems in the Upper Adriatic. “From my point of view, we must do everything to preserve this heritage that we have,” says Begiqi.

Begiqi and other chefs in the region are adapting, viewing the blue crabs not just as pests but as potential ingredients, working them into their menus with remarkable creativity. In a campaign reminiscent of the one trying to get consumers to eat invasive blue catfish in the Chesapeake Bay, Begiqi and his sous chef, Francesco Donaggio, use as much blue crab as possible to safeguard the lagoon. They make a blue crab reduction to use as a filling and for pasta and risotto dishes, and use the meat to make such small dishes (cicchetti) as bao and crab meatballs.

While some Venetians remain loyal to the moeche, finding its flavor more aligned with the Mediterranean palate, others are beginning to appreciate the versatility and affordability of blue crabs. Giorgio Schifferegger, executive chef at JW Marriott Venice Resort & Spa, says he was the first to use blue crabs in Venice, in dishes at Sagra Rooftop Restaurant.

They called it “alien food,” he says. “I started with the soft shell and tried a very classic recipe: battered in flour and fried in hot oil,” the typical preparation of the moeche fritte, he says. “It was very, very good.” Schifferegger notes blue crab dishes, for now, remain a special of the day at Sagra – as the restaurant is committed to serving local cuisine. Keeping in theme with the restaurant’s storytelling through dishes, he’s considering offering a tasting of the blue crab alongside Venetian crabs so customers can learn about this movement.

Eventually, others such as Chiara Pavan, chef at Venissa, a one-Michelin-starred restaurant, also started using the crab. Venissa focuses on “environmental cuisine,” making it an obvious fit to help the battle against the killer crustaceans.

At Algiubagiò, executive chef Daniele Zennaro started buying blue crabs from Joele Trevisan at the Rialto fish market as soon as they were available. Trevisan, who helps operate a family-run fish business, Ittica Trevisan, sees the pros of using the crabs. In May 2023, on his business Instagram account, he posted a picture of soft shells with a caption that reads, in Italian, “Novelty or product of the future??” This summer, Trevisan notes, large hard-shell blue crabs cost the equivalent of about $2.50 a pound, and most of the crabs are bigger because they’re thriving in the waters in Venice.

To put it in perspective, back where I live in the States, Ryan Speckman, co-founder of Locals Seafood in North Carolina, says a retail customer in his area can expect to pay as much as $6.50 per pound for the larger male blue crabs or as low as $2.50 per pound for smaller, lower-quality ones – and during “softie season,” up to $9 per pound. “Bigger crabs have more meat and they’re less work, so they’re more valuable,” says Speckman. “It’s a lot easier to pick half a dozen giant crabs than two dozen small crabs.”

As Speckman explains, soft-shell season along America’s Atlantic Coast begins in spring, when temperatures increase and the blue crabs molt, shedding their shells and turning into a chef’s (and eater’s) prize because they can be fried (and eaten) whole. Hard-shelled crabs are around all year, but they’re more sought-after in warmer months because they’re more active and meatier from eating more.

Chef Daniele Zennaro dresses blue crab taiyaki with ponzu caramel sauce at Algiubagiò. Luigi Avantaggiato for The Washington Post)

In Veneto, the moeche’s soft-shell season happens in the spring and early fall, making it a delicacy to look forward to twice a year. The invasive blue crabs, though, follow the molting pattern of once a year, in the spring.

Zennaro says the blue crabs, once considered tasteless by many Venetians, have adapted to the local environment, developing more flavor as they feast on their version of the Mediterranean diet. “Their meat is much more savory,” he says. “The versatility of the blue crab meat allows you to have a good base for working and studying new pairings and bolder dishes.” He’s now serving a blue crab dish with ponzu caramel sauce and trout caviar, and has plans for frying it as a soft shell or using it “as a condiment with fresh egg spaghetti.”

Inside Sina Centurion Palace, at Antinoo’s Lounge & Restaurant, executive chef Giancarlo Bellino saw blue crabs last year and began to work them into specials, including delicious fried fish balls mixed with crab. Bellino is experimenting with more recipe ideas, including blue crab ravioli.

Tradition is ingrained in Venetian cuisine, and the question remains whether blue crabs will one day become a local staple. But some worry that if they become as fashionable in Veneto as on the Atlantic, they could become as pricey, too. Prices have already risen slightly in Italy compared with last year, while other seafood prices have spiked as a result. Trevisan, the fishmonger, says clams have gone from $5 to $6 a pound to about $10 a pound.

Meanwhile, the blue crab invasion shows no signs of letting up. “Italian recipes, historically, have taken years to form,” Begiqi says. “And this is where we, as young chefs, come into play. We must try to create good recipes that are accessible to all.”