BearBubbles: Interactive Olfactory Enrichment to Encourage Foraging in Zoo Animals

Paper Title

BearBubbles: Interactive Olfactory Enrichment to Encourage Foraging in Zoo Animals

Publication Info

• Topic area: Interactive olfactory enrichment for zoo animal welfare
• Keywords: Olfactory enrichment, Animal-Computer Interaction, zoo animal welfare, black bears, interactive systems, foraging behavior, multi-species design, HCI, behavioral diversity, agency

Background and Problem

• Problem / challenge: Traditional zoo enrichment methods, especially food-based ones, face limitations such as dietary constraints, short-lived effects, and lack of sensory diversity. Existing olfactory enrichment often leads to habituation and is rarely interactive or agency-driven.
• Significance: Enrichment is critical for promoting natural behaviors, reducing stress, and enhancing the welfare of zoo animals. For aging animals like black bears, innovative solutions are needed to address reduced activity and weight management concerns.
• Motivation and related work: Prior research in Animal-Computer Interaction (ACI) has explored interactive systems for various species, but bears remain underrepresented. Olfactory interfaces, despite their relevance to many species, are rare in ACI. This study builds on these gaps by designing an interactive, scent-based system tailored to black bears.

Solution

• Proposed approach: BearBubbles, a proximity-activated scented bubble system designed to provide non-food-based olfactory enrichment for black bears.
• Novelty:
  1. Introduction of a proximity-triggered olfactory interface tailored to black bear sensory priorities.
  2. Integration of animal agency through self-initiated activation and multi-modal engagement.
  3. Deployment of a cost-effective, weatherproof system that minimizes Zookeeper intervention.
  4. Evaluation of enrichment impact on both animal behavior and human stakeholder perceptions.
• Procedure and key techniques:
  • Developed a system with PIR sensors, bubble machines, and scent modules.
  • Designed scents (lemon, maple bacon, peanut butter) based on bear preferences.
  • Conducted a three-week deployment with two black bears, observing behavior, habitat use, and system engagement.
  • Collected data through video coding, spatial tracking, and surveys of visitors and staff.

Results

• Concrete findings:
  • Foraging behaviors increased from 1.0% (post-feeding baseline) to 5.3% during BearBubbles sessions.
  • Locomotion (walking) rates rose from 0.07 bouts/min (post-feeding baseline) to 0.14 bouts/min during deployments.
  • Habitat use expanded to nearly 50% of the enclosure during BearBubbles sessions, compared to ∼20% in post-feeding baselines.
  • Bears triggered the system 198 times across seven sessions, with 44 instances of anticipatory behaviors.
• Advantage over baselines:
  • BearBubbles extended foraging and locomotion behaviors without additional food provision.
  • Increased activity and behavioral diversity compared to post-feeding baselines.
• Experiments / evaluation:
  • Controlled, repeated-measures design with four baseline and seven deployment sessions.
  • Behavioral coding of 1,682 events, spatial heatmap analysis, and surveys of 30 visitors and 3 zoo staff.
• Limitations and future work:
  • Small sample size (two bears) and short duration (three weeks) limit generalizability.
  • Scent-specific preferences could not be statistically analyzed.
  • PIR sensors occasionally mistriggered, and wind affected bubble dispersal.
  • Future work could explore adaptations for other species and refine system durability.

Summary

BearBubbles is a proximity-activated, olfactory enrichment system designed to promote natural behaviors in zoo-housed black bears. Over three weeks, the system increased foraging, locomotion, and habitat use, demonstrating its potential as a non-food-based, agency-driven enrichment tool. Visitors and staff responded positively, highlighting its feasibility and educational value. While limited by sample size and deployment duration, the study provides a scalable framework for interactive olfactory enrichment across species.