A hot-pink flash appears a quarter-mile away, a bright line against the dark green of the mangroves and just above the milky water of the estuary in Celestun, Mexico.

We see them before we hear them - but just barely. Thousands upon thousands of flamingos winter in a sanctuary along this stretch of the Gulf of Mexico coast. In the water, only inches deep a few hundred yards from shore, they find an abundance of shrimp and other small crustaceans.

As our flat-bottom boat drifts closer to the birds, we can hear them chuckling, like an enormous flock of ducks.

"More flamingos here than on all the lawns in Florida," my wife, Kate, says, unable to take her eyes off the roseate display.

Our boat stops 50 yards short of the 6-foot birds on their stick-figure legs. They seem totally unconcerned by our approach or by the three other boats of gawking, camera-clicking tourists.

For 150 pesos (about $11.60) each, we'd boarded the boat an hour from the beautiful Yucatan capital of Merida for a midmorning, 90-minute look at the flamingos and their habitat. The boats hold eight passengers, but we have this one to ourselves.

The estuary runs for miles - a rich feeding ground not just for the flamingos, but for herons, gulls, pelicans, and other waterbirds, as well as for rays and other sea creatures. The estuary, lined by thick stands of mangroves, is washed constantly by the gulf's tides and crystal-clear fresh water that bubbles up from bumps of limestone and sand and flows to the sea.

The shallow water may be great for the birds, but it is tough going for our outboard, and our guide has to constantly tilt the motor to keep the propeller out of the sand. At one point, our boat and another are stuck fast. The guide in the other boat tries to pole his way clear. Failing that, he and one of his passengers hop out and push the boat to slightly deeper water. Our guide stubbornly rocks our boat and pours buckets of seawater over the smoking, straining engine as he tries to get free. I can't help but wonder how long we'd sit in the estuary if the motor were to cook itself to death.

The gulls enjoy our predicament. As our prop plows the white-sand bottom, they hover just astern and feast on whatever comes up. A 10-inch ray patrols the water between us and a nearby mangrove island, bouncing in the small waves we create in our struggle to float.

While we work to get free, the Maya blue sky behind us suddenly turns pink as hundreds of flamingos take to the air in one magnificent burst. The risk of midair collision seems high when that many gangly birds take flight at once, but, fortunately, there are no collisions in this mass takeoff. The sight is jaw-dropping.

It feels like a farewell salute from the flamingos as our boat finally slides free of the bottom and we slowly leave the birds behind.