With a pencil, trace the body of the whale onto the skin of the watermelon. Then with an x-acto knife, carefully cut out around the tracing you have made. To remove the cut out pieces, gently insert the knife as far in as possible without piercing the other side and push the cut piece out.
To make the eyes and water hole, use an apple corer to punch them out. Remove the inside of the watermelon with a large spoon or melon baller and place them in a large bowl. Cut the watermelon pieces away from the rind and cut into chunks. Drain the excess juice from the watermelon into a bowl. Combine the cantaloupe, strawberries, blueberries, green grapes and papaya in a large bowl.
Add watermelon to mixed fruit. Combine well and toss into sculpted whale. Stick the leafy celery stalk inside the water hole as "spouting water". Put a red grape inside each eye hole.