Loons in Florida: Marco Island's Winter Visitor

Is That Really a Loon in Florida?

If you grew up spending summers on a lake somewhere north of the Mason-Dixon line, the common loon is practically wired into your memory — that eerie, wailing call across still water at dusk. So when someone spots a low, dark bird riding the swells off Marco Island and half-jokingly asks, “wait, is that a loon?”, our captains usually just smile and say yes. It really is.

Common loons (Gavia immer) breed on freshwater lakes across Canada and the northern U.S., then migrate south for the winter — and a good number of them choose the Gulf of Mexico as their off-season address. From roughly November through March, you can spot them scattered through Big Marco Pass, Gordon Pass, and the open, nearshore waters off the Ten Thousand Islands, floating low and alone, occasionally slipping under for a dive that can last close to a minute. They won't look much like the bird on a cabin's welcome sign, though — more on that below.

Why Loons Go Silent and Drab in Winter

The confusion makes sense, because the loon Floridians see is basically a different-looking bird from the one up north. In breeding season, a common loon wears a striking black-and-white checkerboard back, a glossy black head, and a necklace of white stripes — sharp enough to spot from a mile away. By the time it reaches the Gulf, all of that is gone. Winter loons fade to a plain, soft gray-brown above and white below, with a smudged, unfinished-looking line between the two colors on the neck instead of a clean collar. The bill goes from solid black to a paler, washed-out gray. It's camouflage for a bird that's no longer trying to attract a mate — just trying to eat and get through the season.

The voice disappears too. That famous wail and tremolo is breeding-territory talk, aimed at rivals and mates on a home lake, and loons simply don't use it here. A wintering loon on the Gulf is a quiet bird — you might hear a short, single note if one gets startled, but nothing like the wilderness soundtrack most people associate with the species. Combine the silence with the drab plumage and you get a bird that hides in plain sight, floating past charter boats and pass fishermen who have no idea they're looking at a genuine northern icon.

Where to Spot Loons Around Marco Island

Loons like open water with a food supply, and Southwest Florida's passes deliver both. Big Marco Pass is one of the more reliable spots — the swirling current there concentrates baitfish, and a loon will sit and dive the same stretch of water for long spells. Gordon Pass, Coon Key Pass, and the open Gulf just off Tigertail and Cape Romano can hold them too, especially on calmer days when the swells aren't too big for a low-riding bird to sit comfortably.

Don't picture a raft of them bobbing together the way you might imagine from a northern lake during fall migration. Florida's wintering loons tend to scatter as individuals, spaced out across the passes and nearshore Gulf rather than grouping up, so a sighting is usually one solo bird, sitting low with its dagger bill tipped slightly upward. It's one more reason our captains keep a running mental list of what's out there each week — between the loons, the wading birds working the mangrove edges, and the river otters that occasionally slip through the same quiet backwaters, winter on these waters is busier than it looks from the beach. Most sightings happen from the boat, on the same routes our dolphin tours run through the passes every day.

Loon vs. Cormorant vs. Grebe: How to Tell Them Apart

Loons get misidentified constantly, mostly because Southwest Florida already has several dark, low-swimming waterbirds sharing the same passes. The double-crested cormorant is the most common look-alike — both sit low with just the head and neck showing, but a cormorant has a hooked bill tip and a longer, kinked neck, and it's far more likely to be perched on a channel marker with its wings spread to dry. Pied-billed grebes are smaller and stockier, with a stubby, chicken-like bill instead of the loon's straight dagger. And a brown pelican, while it dives plenty, does so from the air in a dramatic plunge rather than the loon's slow, unhurried disappearing act from the surface. Once you know what to check — bill shape first, then how the bird dives — a loon stops looking like a mystery and starts looking like, well, a loon.

When to Look for Loons in Southwest Florida

Loons are one of the more reliably-timed visitors on our wildlife calendar. They start trickling in as cold fronts push south in late October and November, hang around through the winter, and head back north by April as the water warms and breeding instincts kick in. That window overlaps almost exactly with our best dolphin-watching stretch, prime manatee season over in Rookery Bay, and the cooler, calmer mornings that make winter one of the most comfortable times to be out on the water at all.

If spotting one is on your list, the honest answer is that we can't promise a loon on any specific trip — sightings are never guaranteed, and a scattered winter visitor isn't going to pose for you the way a pod of dolphins usually will. But our captains run these same passes daily all winter, and a quiet gray bird sitting low and diving long in Big Marco Pass is exactly the kind of thing they'll point out without you having to ask. Book a winter dolphin tour and keep an eye on the open water between the wakes — loon season and dolphin season line up almost perfectly.