Ahoy there, mates, all aboard for an educational cruise. Throughout summer and early fall, boats are departing daily for cruises to see offshore lighthouses, tidal wetlands and neighboring whale populations. Along the way, you'll learn about the area's wildlife, ecosystems and the humans who make their living on the water.

"Long Island has a fantastic maritime history," says retired oral historian Alice Kendrick, 81, of Freeport, who has taken several educational boat tours with Long Island Traditions of Port Washington. "You always learn something that you didn't know before."

Here are cruises that open your eyes to the watery world that surrounds us.

1. East End Lighthouse Cruises

WHEN | WHERE 4 p.m. Saturday, July 25 (haunted cruise), Aug. 8, 13, 27 and 29, as well as other selected dates through Oct. 25 from East End Seaport Museum & Marine Foundation, Third Street, Greenport

INFO 631-477-2100, eastendseaport.org

ADMISSION $20-$95

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The Town of Southold contains eight lighthouses, and this two-hour cruise regularly visits one of the most iconic -- for the North Fork, anyway: The Long Beach Bar Lighthouse, also known as the Bug Light, is located off the tip of Orient State Park.

A descendant of the last lighthouse keeper gives this guided tour. "It really is an opportunity to see living history," says museum director Nicole Desiree.

The museum also offers a five-hour "super cruise" of up to 12 lighthouses in New York, Connecticut and Rhode Island on Sept. 14. Make your reservations early.

2. Atlantis Explorer

WHEN | WHERE Noon, 2 and 4 p.m. weekdays through Labor Day and noon and 2 p.m. weekends through Sept. 30 from Long Island Aquarium, Riverhead.

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INFO 631-208-9200, longislandaquarium.com

ADMISSION $20 ($13 if added to aquarium admission)

On an "interactive adventure" along the Peconic River and through Flanders Bay, an onboard educator points out wildlife including shorebirds and turtles, and introduces kids to horseshoe crabs on board. The boat stops at a private beach where kids can look for seashells and help seine for small fish. "It's a really nice, peaceful and relaxing but interesting and informative trip," says Darlene Puntillo, marketing director.

3. Boating with the Baymen

WHEN | WHERE 2-5 p.m. Sept. 26 from 85 Woodcleft Ave., Freeport. Reservations required.

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INFO 516-767-8803, longislandtraditions.org

ADMISSION $40 ($20 younger than 16)

Long Island Traditions sponsors a guided tour through South Shore waterways aboard the Miss Freeport, a 72-foot charter boat with a heated cabin. Speakers, including members of families that have worked the waterfront for many generations, tell of surviving a hard life and natural disasters such as superstorm Sandy.

Passengers "learn how fishermen, baymen and bay house owners cope with these historic events," says Nancy Solomon, executive director.

4. Discovery Wetlands Cruises

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WHEN | WHERE Boat leaves according to the tides on many scheduled dates through Oct. 19 from Stony Brook Yacht Club, Shore Road, Stony Brook. Reservations suggested.

INFO 631-751-2244, wmho.org

ADMISSION $35 ($28 advance), $20 younger than 6 ($18 advance)

Board the Ward Melville Heritage Organization's 27-passenger pontoon boat Discovery for an hour-and-a-half cruise around Stony Brook Harbor and local wetlands. A naturalist discusses waterfowl, the salt marsh and historic buildings such as the Gamecock Cottage. "They talk a bit about the ecosystem of the wetlands and its importance to Long Island, as well as Native American settlements in that area," says Marie Gilberti, the organization's communications manager.

5. Viking Fleet Whale Watching Trips

WHEN | WHERE 9:30 a.m.-3:30 p.m. Sundays through Sept. 6 from Viking Dock, 462 W. Lake Drive, Montauk. (Check in at the office one hour before departure.)

INFO 631-668-5700, vikingfleet.com/whalewatching

ADMISSION $75 ($49 ages 5-12).

The 140-foot Viking Starship travels as far as Block Island in search of minke and finback whales. Passengers have also seen leatherback turtles, common bottlenose dolphins, hammerhead sharks and ocean sunfish.

FOR MORE

Want to see the Fire Island seashore by water?

Take a free 3-mile canoe trip with park rangers along the Great South Bay marshes in Watch Hill. Be warned: You'll probably have to paddle.

Guides take passengers in three-seat canoes along the coast of the largest contiguous salt marsh on Fire Island, ducking into Goose Neck Pond on the bay side, with a second stop in an area known as Long Cove. "It's a new perspective," says park ranger Kristin Santos, who leads the tours. "And some people learn a new skill" -- that being open water canoe paddling, which is demonstrated at the beginning of the trip.

Spend the rest of the day at the lifeguarded beach, which has a snack bar, restaurant and general store, along with a trail walk through the state's only federally designated wilderness area.

WHEN | WHERE 11 a.m.- 1 p.m. Saturdays and Sundays through Sept. 6 (5-7 p.m. Sept. 4 is a special sunset trip) from Watch Hill Visitors Center. All trips are weather-dependent. Reservations recommended.

GET THERE Take 8:30 a.m. or 10 a.m. ferry from Patchogue to Watch Hill (631-475-1665)

INFO 631-597-6455; nps.gov/fiis

COST Free ($11-$17 cash-only ferry)