North River Lobster Co., which bills itself as the city’s only floating lobster shack, opened this past weekend for its fifth season.

Sailing from Pier 81 on the West Side a few times daily, the shack offers classic lobster rolls and — under new CEO Craig Kanarick — new variations. Those include the Lower East Side lobster roll, with scallion, onion cream cheese, chives and “everything bagel” seasoning on top of a potato roll.

Signature cocktails can be upgraded to a “Colossal Claw Cup” or an even larger pitcher for sharing. The boat sails a few times during the week and restaurant goers can stay as long as they want.

Other options include the BLLT roll, with lobster, thick-cut bacon, lettuce, tomato, and a bit of mayo on a potato roll.

There’s also the Asian Spicy, with Southeast Asian chili sauce, radish, scallions, and bibb lettuce and the California, with avocado, grapefruit, olive oil, lemon and arugula.

Elsewhere, check out the “amped up” cocktail list with “FROZÉ! FROZÉ! FROZÉ!“ — a frozen granita recipe of Cloud Chaser rosé and elderflower; and the “Queen Mary,” a twist on a typical Bloody Mary with Belvedere vodka and shrimp garnish.