Fagen et al (2014)

• Positive Reinforcement Training for a Trunk Wash in Nepal's Working Elephants: Demonstrating Alternatives to Traditional Elephant Training Techniques


  18/01/2022, 04:55
• Many trainers of animals in the zoo now rely on positive reinforcement training to teach animals to voluntarily participate in husbandry and veterinary procedures in an effort to improve behavioral reliability, captive management, and welfare
• Captive elephant handlers in Nepal still rely heavily on punishment- and aversion-based methods
• Subjects


  • 5 female elephants, 4 juveniles and 1 adult

  
• Training methodology


  1. Teach the bridge between primary and secondary reinforcer

  2. Train in basic tasks using capture, lure, and shaping techniques

  3. Train the trunk wash behaviour
• Positive reinforcement training


  Improves behavioural reliability, captive management, and welfare
• Traditional elephant training methods

  Rely on punishment and aversion techniques
• The current gold standard for detecting active tuberculosis infection in elephants is via bacterial culture of a sputum sample obtained using a procedure known as the trunk wash
• Researchers attempting to monitor and treat TB in captive, working elephants in Nepal have encountered significant challenges in consistently obtaining quality trunk wash samples for TB testing
• Capture technique


  Useful starting place for a behavior that an animal spontaneously does without training or that is similar to a spontaneous behavior (e.g., sitting in a dog). Trainer waits for the animal to perform this natural behavior and then "captures" it by marking and rewarding it repeatedly.
• Lure technique


  Used for behaviors that are not natural behaviors for an animal. The animal is initially drawn into a wanted body position by strategic placement of a reward. This body position is rewarded and is used as the starting point from which to work on the desired behavior.
• Shaping


  Relies on natural variation in the quality of the behaviors offered during repetition and works by rewarding only the behaviors offered that are closer to the eventual goal. This rewarding of the "best" behaviors offered incrementally brings the average response closer to the desired goal.
• Basic behavioral tasks trained

  • Trunk here
  • Trunk up
  • Bucket
  • Blow
  • Steady
• Trunk here


  The elephant gently places the end of her trunk in the trainer's outstretched hand in preparation to allow the instillation of saline or water into her trunk. Trained using lure method.
• Trunk up


  The elephant lifts her trunk upward to allow the saline or water to run down to the base of her trunk. Used as a replacement behavior for those elephants who attempted to drink the solution. Trained using lure and shaping techniques.
• Bucket


  The elephant places the distal end of her trunk in a bucket in preparation to blow. Trained using lure technique.
• Blow


  The elephant gives a strong exhale through her trunk to blow out the solution for sample collection. Trained by capturing the natural exhale associated with breathing and shaping it for more force.
• Steady


  The elephant holds the position she has just been previously asked to do. Trained using shaping to increase the length of time a position was held.

  
• Verbal cues were monosyllabic, distinctive words created to mean nothing in either English or Nepali, to avoid any misconception on the mahouts' part that the elephants could potentially comprehend the meaning of the verbal cues.
• Three other tasks - targeting, trunk down, and trunk out - were introduced but quickly abandoned or deemphasized as they were not needed for performance of a trunk wash in this population.
• Behavioral chaining


  Enables separately trained behaviors to be performed in succession in response to cues. One theory is that once a behavior is learned to be strongly associated with the primary reinforcer, the behavior itself becomes a reinforcer for the behavior that precedes it.
• Behavioral chaining training process

  1. Elephant taught to blow consistently and exclusively into the bucket

  2. Elephant taught to string the other behaviors together in small sequences to ensure smooth transitions

  3. Trainer strung together all the behaviors: trunk here with a short steady, trunk up with a longer steady, and then bucket and blow
• Desensitization and counterconditioning


  A new, potentially negative experience (syringe and sample fluid) was introduced incrementally and paired with a reward to make the experience less aversive to the elephant.
• All elephants were started on 0.9% saline as the sample medium, then transitioned to plain water for training purposes.
• Given the individuality of each elephant and different rates of learning, there was no prescribed amount of time spent at each stage in the training process. Progression through the training was dictated by the success of the individual elephant, and training plans were tailored to the individuals' needs at the discretion of the trainer.
• Data collected


  • Session times
  • Number of offers
  • Performance tests
• Performance tests


  Starting after Session 10, a test was administered to each elephant approximately every five sessions. Elephants were tested on all the previous behaviors they had been taught, with a passing score taken to be 80% or higher for each task.

  
• Elephants


  • Juvenile elephants successfully learned the trunk wash in the time available for the study
  • Adult elephant (Elephant 5) did not learn the trunk wash
• Trunk wash training


  1. Elephant 1 passed after 30 training sessions

  2. Elephant 2 passed after 25 training sessions

  3. Elephants 3 and 4 passed after 35 training sessions

  4. Elephant 5 did not pass
• Training session duration


  Mean duration of 12 minutes
• Total training time ranged from 257 minutes for Elephant 2 to 451 minutes for Elephant 4

  
• Mean total training time was 378 minutes among all elephants and 367 minutes among those elephants who successfully passed the trunk-wash test

  
• As training progressed


  Elephants' performance improved from a mean success rate of 39.0% after 10 sessions to 89.3% after 35 sessions

  
• The mean percent correct never reached 100% because as sequences of behavior received a passing score, all individual behaviors within the sequence received a default score of 90%
• Relative difficulty of tasks

  • Trunk-here task required more offers than both the bucket and blow-into bucket tasks
  • Steady task data not included as it was too difficult to measure
• A one-way analysis of variance showed a significant difference (p = .017) in relative difficulty for each of the basic behavioral tasks
• Elephant 5 never passed her blow into bucket, desensitization to syringe, and steady tests
• Elephants 2 and 4 also never passed their steady tests, despite being able to pass their full trunk wash tests
• The ability to pass an individual behavioral test was dependent both on the relative difficulty of the task as well as when the task was first introduced in the training process
• Elephant 5's failure to complete the training may have been due to significant distractions, potential vision impairment and trunk weakness, age, and the fact that the trainer was better able to learn from failures and successes in the juvenile elephants