What Long Key Bridge offers and when to fish it

Long Key Bridge connects Long Key to Conch Key in the middle Keys, roughly 60 miles south of Miami. The bridge itself—a 2.2-mile span built in 1938—sits over shallow flats, channels, and deeper water that hold tarpon, permit, bonefish, and snappers depending on the season and tide. The structure creates current breaks and depth changes that concentrate fish, making it productive year-round but with distinct seasonal patterns.

Spring (March through May) brings the heaviest tarpon action, particularly around the full moon when large schools move through the channels. Summer heat pushes permit and bonefish into deeper water, but snappers and groupers stay active. Fall (September through November) is less crowded and still holds tarpon, along with permit moving back into the shallows. Winter brings cooler water and fewer tarpon, but the flats hold bonefish and permit more consistently.

Tide matters more here than almost anywhere else in the Keys. Rising tide pushes fish onto the flats; falling tide concentrates them in channels and deeper holes. The bridge's pilings create slack water on both sides—the east side typically holds fish on incoming tide, the west side on outgoing. Most anglers fish the two hours before and after the tide change, when current slows and fish feed actively.

Key Takeaways

  • Long Key Bridge holds tarpon in spring, permit and bonefish year-round, and snappers in deeper channels, with seasonal patterns that shift what species you'll encounter.
  • Tide is the primary factor—fish the slack water around tide changes, and position yourself on the east side during incoming tide and the west side during outgoing tide.
  • The bridge pilings and shallow flats require accurate casting and light tackle; sight-fishing for permit and bonefish demands polarized sunglasses and a clear water day.
  • Access is from the bridge itself (walk or drive to the shoulder), or by boat from nearby Marathon or Conch Key; no formal boat ramp sits directly at the bridge.
  • Water clarity and weather determine success more than any other factor—cloudy days and rough water make sight-fishing nearly impossible.

Tarpon fishing at the bridge in spring

Tarpon arrive in numbers from March through May, moving through the channels and along the bridge structure on their spawning migration. Schools of 10 to 50 fish are common, and individual fish run 50 to 150 pounds. The full moon phase (three days before through three days after) concentrates the largest schools, though tarpon move through on most tides during the season.

Fish the channels on both sides of the bridge during the hour before and after slack tide. Cast large flies (4/0 to 6/0 tarpon patterns in black, orange, or chartreuse) or live mullet ahead of moving schools. Tarpon are sight-feeders in this clear water—you'll see them cruising or tailing in the shallows. Use 12- to 16-weight fly rods with 80- to 100-pound tippet, or medium-heavy spinning tackle with 30-pound braid and a 60-pound fluorocarbon leader. The fight is explosive and can last 30 minutes or more; expect to lose fish on the bridge pilings.

Spring tarpon fishing here draws crowds, especially on weekends and during the full moon. Arrive early or fish the slack tide at dawn. The bridge shoulder fills quickly, and boat traffic increases. If you're wading, stay aware of current and depth changes—the bottom drops suddenly in some channels.

Permit and bonefish on the flats

Permit and bonefish live on the shallow flats year-round, though they're most accessible during spring and fall when water temperatures are moderate. Permit run 15 to 30 pounds and are notoriously difficult to hook and land; bonefish average 4 to 8 pounds and are faster and more aggressive. Both species feed on crabs and small shrimp, and both require sight-casting and precise presentation.

Fish the flats on incoming tide when water pushes onto the shallows and fish move in to feed. Polarized sunglasses are essential—you need to see the fish before you cast. Look for tails breaking the surface, dark shapes moving slowly, or nervous water where fish are feeding. Cast a small crab pattern (size 2 to 4) or shrimp fly 6 to 8 feet ahead of the fish and let it sink. Permit are cautious and may refuse a fly that lands too close; bonefish are more aggressive but spook easily if you cast directly at them.

Use 8- to 10-weight fly rods with 20- to 30-pound tippet for permit, or 6- to 8-weight for bonefish. Spinning tackle works too—light jigs (1/8 to 1/4 ounce) or small soft plastics on 10- to 15-pound braid. The flats are shallow (2 to 4 feet), so wade slowly and watch for shadows. Permit and bonefish spook at the sight of a wading angler; approach from downwind and move quietly.

Snappers and groupers in the channels

Deeper channels on both sides of the bridge hold mangrove snappers, mutton snappers, and small groupers year-round. These fish are less glamorous than tarpon or permit but are reliable and fun on light tackle. Snappers run 1 to 5 pounds; groupers are similar in size but fight harder. Both eat small crabs, shrimp, and baitfish.

Fish the channels during slack tide or slow current. Drop small jigs (1/4 to 1/2 ounce), live shrimp, or cut mullet to the bottom near the pilings. Snappers bite aggressively and are good table fare. Groupers are more selective and often hide in the structure; you may lose tackle to the pilings, so use heavier leader (20- to 30-pound fluorocarbon) and be ready to set the hook hard and keep pressure on immediately.

This fishing works on cloudy days and rough water when sight-fishing for permit or bonefish is impossible. It's also a good option if you don't have polarized sunglasses or if the sun angle is wrong for seeing fish on the flats.

Access and logistics

Long Key Bridge is accessible by car and foot. The Overseas Highway (US 1) crosses the bridge; pull onto the shoulder on either side and walk to the railings. Parking is limited and informal—there's no dedicated lot, so arrive early or fish during off-peak hours. The bridge is public, and fishing from it is legal, but stay alert to traffic and don't block the roadway.

If you're fishing by boat, launch from Marathon (Boot Key Harbor or Vaca Cut) or from Conch Key. The bridge is roughly 10 to 15 minutes by boat from either location. Shallow-draft skiffs (18 to 22 feet) work best because much of the water around the bridge is 3 to 5 feet deep. Deeper channels exist, but you'll spend time navigating around the shallows.

Bring plenty of water, sunscreen, and a hat—there's no shade on the bridge. Polarized sunglasses are non-negotiable for sight-fishing. A headlamp is useful if you fish the dawn slack tide. Tide tables are essential; download them before you go or check them on your phone. The difference between a productive tide and a dead one is often just 30 minutes.

Weather and water clarity

Long Key Bridge fishes best in clear water with light wind. Cloudy skies and rough water make sight-fishing impossible, and you'll be limited to blind casting or fishing the channels with bait. A north or northeast wind pushes water off the flats and makes the bridge less productive; a south or southwest wind pushes water onto the flats and improves conditions.

Water clarity varies with season and recent rain. Spring and fall typically offer the clearest water. Summer heat and afternoon thunderstorms can cloud the flats. Winter cold keeps water clear but also pushes fish deeper. Check the forecast before you go—a day with light wind, clear skies, and a favorable tide is worth planning around.

If you arrive and the water is too rough or cloudy, consider fishing the channels instead of the flats, or move to a nearby location like Conch Key or Grassy Key. The Keys have dozens of bridges and flats within 30 minutes of Long Key, so flexibility pays off.

Frequently Asked Questions

Can I fish Long Key Bridge without a boat?

Yes. Walk or drive to the bridge shoulder and fish from the railings. You can reach the channels and some of the flats from the bridge itself, though a boat gives you access to more water and lets you position yourself with the tide. Many anglers fish the bridge on foot and catch tarpon, permit, and snappers without leaving the pavement.

What's the best tide for Long Key Bridge?

Slack tide (the hour before and after the tide change) is most productive because current slows and fish feed actively. Rising tide pushes fish onto the east-side flats; falling tide concentrates them in the west-side channels. Check tide tables before you go and plan to fish the slack water around your target species' preferred time.

Do I need a fishing license to fish Long Key Bridge?

Yes. Florida requires a saltwater fishing license for anyone 16 and older. You can buy a 3-day, 7-day, or annual license online through the Florida Fish and Wildlife Conservation Commission website or at most bait shops in Marathon. Licenses are inexpensive and can be purchased the day you fish.

What flies or lures work best at Long Key Bridge?

For tarpon, use large flies (4/0 to 6/0) in black, orange, or chartreuse, or live mullet. For permit and bonefish, use small crab patterns (size 2 to 4) or shrimp flies. For snappers and groupers, use small jigs (1/4 to 1/2 ounce) or live shrimp. Bring a variety because fish preferences change with season and water conditions.

Is Long Key Bridge crowded?

It can be, especially during spring tarpon season and on weekends. Arrive early or fish during weekdays and off-season months (June through August) for more solitude. The bridge is popular because it's productive and accessible, so expect company during peak times.