1. Behavior Modification of the
Elasmobranch Species Southern
Stingray (Dasyatis americana)
Using Operant Conditioning
Chris Perkins
Mystic Aquarium Intern
Fish and Invertebrate Department

4. Desired Behavior
To have all three southern stingrays respond to a
single discriminative stimulus (SD) by swimming
up the side of the tank to receive food at the
surface.

5. Benefits
•Facilitates feeding the southern stingrays
•Desensitizes them to human contact
•Can build other behaviors off of this one
•Disrupted hierarchy among the southern stingrays

6. The Training Program
3 minute feeding sessions
Up to 2 sessions per day
No less than 1 hour between sessions
Spot light acts as SD

7. Successive Approximations
Have the southern stingrays station at the
bottom when given the SD.
Feed the southern stingrays on the side of the
tank.
When the southern stingrays are near the
surface offer food from hand.
Eventually a pole is not required to bring the
southern stingray to the surface to receive
food.

8. Station 1 Station 2a
Station 2b Station 3

9. Stations 4 &5

10. Jackpot Rewards System
Southern stingrays were rewarded for coming to
the surface by receiving “better”/more food at
the surface than on the pole.
Pole: Squid
Surface: Fatty Herring
Pole: ¼ of a Herring
Surface: Squid/
Fatty Herring

11. Changes Made to the
Program
•Different SD’s
•Different Reward Sizes
•Surface Sessions

13. 0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50
PercentofRewards
SessionNumber
Station 1
Station 2
Station 3
Station 4
Station 5
Rewards: Hoover
0
10
20
30
40
50
60
70
80
90
100
50 60 70 80
PercentofRewards
SessionNumber
Station 1
Station 2
Station 3
Station 4
Station 5

14. 0
1
2
0 5 10 15 20 25 30 35 40 45 50
Response
SessionNumber
0
1
2
50 55 60 65 70 75 80 85
Response
SessionNumber
Response: Hoover
1: No Reaction
2: Stationed on bottom
3: Came to Surface

15. 0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50
PercentofRewards
SessionNumber
Station 1
Station 2
Station 3
Station 4
Station 5
0
10
20
30
40
50
60
70
80
90
100
50 60 70 80
PercentofRewards
SessionNumber
Station 1
Station 2
Station 3
Station 4
Station 5
Rewards: Tomboy

16. 0
1
2
0 5 10 15 20 25 30 35 40 45 50
Response
SessonNumber
0
1
2
50 55 60 65 70 75 80 85
Response
SessionNumber
Response: Tomboy
1: No Reaction
2: Stationed on bottom
3: Came to Surface

17. 0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60
PercentofRewards
SessionNumber
Station 1
Station 2
Station 3
Station 4
Station 5
0
10
20
30
40
50
60
70
80
90
100
50 60 70 80
PercentofRewards
SessionNumber
Station 1
Station 2
Station 3
Station 4
Station 5
Rewards: Roomba

18. 0
1
2
0 5 10 15 20 25 30 35 40 45 50
Response
SessonNumber
0
1
2
50 55 60 65 70 75 80 85
Response
SessionNumber
Response: Roomba
1: No Reaction
2: Stationed on bottom
3: Came to Surface

19. Conclusions
2 of 3 southern stingrays successfully exhibit
desired behavior
Roomba is making progress to the final goal
Possible altered hierarchy among southern stingrays

21. Acknowledgements
Mystic Aquarium an Institute For Exploration
Jill Reeves
The Marine Theater Trainers
Samantha Shannon
Cris Sodergren
Monique Park
Megan Priede
Gus Stout

23. Questions?