Environmental Enrichment Policy – Birds


Boston University is committed to observing Federal policies and regulations and AAALAC International standards for the humane care and use of animals.1 Humane considerations and current policies  require that research animals, whenever possible, must have the opportunity to interact with conspecifics and to benefit from Environmental Enrichment (EE). This policy provides guidelines for handling and EE for birds 2.

Birds are intelligent animals and require species-specific socialization and handling techniques.  The provision of frequent and gentle handling and daily routines have a calming effect on these animals and will reward laboratory animal staff as well as investigators with a more compliant research subject.  Interaction with handlers is a form of environmental enrichment.  In addition, manipulable objects, toys, and modified caging should be provided.


 A.   To define environmental enrichment for birds, including various ways to “facilitate the expression of species-typical behavior and promoting psychological well-being through physical exercise, manipulative activities or cognitive challenges”.1

B.   To outline how exceptions to this policy should be considered by the IACUC or BU ASC  veterinarians.


  1. Compatible birds will be pair- or group-housed if temperament and normal social behavior allows.
  2. Birds may, if scientifically justified in an approved IACUC protocol, be individually housed.  Unless otherwise indicated in the approved protocol, individually housed birds will be provided housing which allows visual, auditory or olfactory contact with other birds.
  3. If a protocol exception to limit or exclude enrichment is to be included in an IACUC submission, the Principal Investigator (PI) is required to consult with veterinary staff during protocol development to discuss the special circumstances that might limit participation in the enrichment program.  The PI will need to include the requirement and scientific justification for single housing in the IACUC protocol, specify the approximate duration of single housing and/or the requested exemptions from any EE strategies included in this policy or associated SOP.  If no exemptions are approved within the protocol, then the policy and associated SOP will be followed.  Once the protocol is approved, the PI must inform BUASC of the approved exceptions to this policy.
  4. Certain medical or compatibility conditions may require that birds be individually housed or that other elements of the enrichment program be changed.  These determinations will be made by a veterinarian and documented in the animal’s record.  Veterinary exemptions to this policy do not require IACUC approval.
  5. Singly housed birds are presumed to need more environmental enrichment than pair- or group-housed birds and may be provided with extra cage enhancements unless an exception to limit or exclude EE is justified in the IACUC approved protocol for scientific reasons.  Singly housed birds will be observed daily and will have their well-being evaluated at least monthly by a veterinarian or adequately trained veterinary staff.  The assessment and recommendations for continued single housing will be reviewed and approved by the Attending Veterinarian or designee.


 A.   The best way to provide EE for birds is cage enhancements and items that can manipulated. Novelty of    enrichment through rotation or replacement of items should be a consideration. The following are examples of acceptable EE.              

1.   Perches. These should be provided in the housing enclosure.

2.   Toys. These should be replaced when worn or broken.

3.   Partial to fully solid flooring with bedding to encourage scratching and foraging.

B.     Allow birds to forage for their food (which should be as varied as possible), either by scattering the food in wood-shavings on the aviary floor, by hiding it amongst shredded paper in a large trough, or by providing it in a form where birds have to work e.g., stuck together in a grain-block. Operant feeders, where a button must be pecked to release food, may occupy solitary birds, but cannot be recommended for group-housed birds as they may not allow birds to feed simultaneously and hence could result in increased competition and risk of feather pecking.

C.     Allow egg-laying birds the opportunity to perform nesting behavior by the provision of suitable nest-boxes and building material.

D.    Group activities for compatible birds must be scheduled regularly. Allow sufficient space for running or flying activity, and consider ways of increasing the value of the space available. Perches or roosting shelves can be incorporated cheaply into all housing systems. In small cages perches can be inserted at night to allow roosting but removed during the day to allow unrestricted space

E.    House birds in suitable stable social groups. If birds must be housed individually arrange the cages so that they have visual contact with others. Since birds seem able to perceive 2-dimensional images the use of mirrors may also reduce the negative effects of social isolation.


 1.   The Guide for the Care and Use of Laboratory Animals. 2011.  NRC ILAR.  P. 52-55.  Environmental Enrichment.

2.   ILAR Journal 2005 Volume 46(2) Enrichment Strategies for Laboratory Animals


2.1 Thomas L. Wolfle.  Introduction.  Environmental Enrichment.


BU IACUC Approved January 28, 2014