My Dear Watson

Fresh is the word when it comes to fish, and it doesn't take a Sherlock Holmes to deduce that the seafood shanties in Watson Island Marina, one of the first stops for local commercial fishing boats, would be an opportune place to purchase some of the very freshest. Two weathered seafood markets, Casablanca and DeArmas, stand a stone crab's throw from each other right by Biscayne Bay, just under the MacArthur Causeway at the point where it makes its bend toward Miami (or Miami Beach, depending upon the direction you're headed). Inside these shops you'll find a lineup of fishmongers with razor-sharp knives filleting fish so fast that, to paraphrase Satchel Paige, they can start to cut a grouper as you flick off the light switch and be finished before the bulb goes out. Bargains abound: grouper just $2.99 per pound, mahi-mahi $3.99, yellowtail snapper $4.99, fresh shrimp $8 to $20. (Don't hold me to these numbers -- they fluctuate from week to week.)

On weekends you can do more than just snap up snappers at market prices; both spots set up food concessions where the pristine seafood gets prepped into a number of tasty snacks. Specialties of the shack at Casablanca: a dozen oysters on the half-shell ($7); three ceviches (octopus, grouper, and conch) that come in small (really too small) plastic take-out containers ($3 apiece); and a soft, flaky-crusted homemade salmon empanada ($3). You can purchase soda and water here (or bring your own beer), but the mostly Hispanic family crowd chills out by sipping coco frío (chilled coconut) through a straw.

DeArmas offers equally small plastic containers of similarly satisfying appetizers: conch ceviche, mayo-based shrimp salad, and shelled oysters. Concerning your main course: Purchase a fish filet at DeArmas, take it to the stand outside, and have them fry it up golden brown ($3 extra); a sizable salad or pile of fried green plantains are available as sides for $2 each. This outdoor stand also runs a daily special -- on one occasion pretty decent paella with grouper, squid, teeny shrimp, mussels and peas ($10 with one side).

The fare at these fisheries is fresh and honestly prepared, but it's the visuals that make lunching here worthwhile. Twenty tables set up under a sun-sheltering blue nylon awning offer vantage points to the Miami skyline, to whirlybirds landing and taking off from a nearby pad, and to pelicans posturing on bobbing boats -- the image of which, interposed with that of people enthusiastically filling their mouths with fish, brings to mind an Ogden Nash couplet: "A wonderful bird is the pelican/Its beak can hold more than its belly can."