Clean the celery (remove the threads), wash and cut into fine pieces. Dice salmon and trout. Wash the dill, shake dry and cut finely
For the vinaigrette, mix vinegar, mustard and maple syrup. Season with salt and pepper. Stir in dill. Fold in the oil. Mix celery, salmon and trout carefully. Pour over vinaigrette, mix carefully. Arrange in serving bowls