Remove the pit from the avocado. Use a spoon to scoop out the insides of the avocado and place it in a medium bowl. Mash the avocado with a fork or potato masher. Add the pico de gallo and mix well.
Add the tuna to the bowl and mix well. Serve the tuna salad with your choice of whole-wheat crackers, whole-wheat pitas or lettuce wraps.