One trip to the island (maxing out the storage container.)
4 goliath beetles. (6000 each)
23 fruit beetles. (6000 each)
5 cyclommatus stags. (8000 each)
4 horned elephants. (8000 each)
1 horned atlas. (8000 each)
1 rainbow stag. (10,000 each)
1 shark. (15,000 each)
267,000 bells total. 
It would have been 10k more but I donated my first Giant Stag to the museum (like I do for the first time I catch anything that hasn't been donated.)