Scatter the clams and oysters on a baking sheet and roast in the oven just until they begin to open up, 5 to 7 minutes. This will make the shucking process easier.
In a large bowl, combine the lemon juice and lime juice. Stir to combine.
Shuck the oysters and clams, with their natural juices, into the bowl. Chop the shrimp and add to the bowl. Stir gently to combine the seafood with the citrus juice. Cover and allow to sit for 2 hours in the refrigerator.
Add the cucumbers, red onions, cilantro, parsley, tomatoes and chile to the seafood and mix well. Add the olive oil and salt and pepper to taste. Mix again and allow to sit in the refrigerator for an additional 1 1/2 hours before serving.
Serve chilled, with corn tortilla chips.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.