Drain and rinse the cannellini beans thoroughly under cold water.
Open the Wild Planet tuna; you can include the natural juices for added Omega-3s or drain slightly if preferred.
Finely dice the cucumber and red onion, and halve the cherry tomatoes.
In a small glass jar or bowl, whisk together the extra virgin olive oil, lemon juice, dried oregano, sea salt, and black pepper until emulsified.
In a large mixing bowl, combine the tuna, rinsed beans, cucumber, tomatoes, red onion, and kalamata olives.
Drizzle the lemon-herb vinaigrette over the salad components.
Gently fold the ingredients together using a spatula to ensure the tuna stays in chunky flakes and the beans remain intact.
Top with freshly chopped parsley and serve immediately or chill for 30 minutes to let the flavors meld.