DEALING WITH STRESS IN BIRDS
By David Hannon, DVM, Dipl. ABVP-Avian
Whether you have one pet budgie or an aviary full of champion macaws, limiting stress is essential for the health and well-being of your birds. Stress can occur in many different forms, some physical and some mental, and can be mild to severe. Stressors cause the release of a hormone known as cortisol from the adrenal glands. In the initial stages of stress, this hormone helps the bird’s body deal with its effects, but over the long run, it can the bird to be immunologically suppressed and unthrifty.
Stress typically occurs in three stages. The first stage is commonly known as “fight-or-flight.” In this stage, the bird first responds to the stressor with an adrenaline surge, which prepares the body for action by shutting down non-essential functions, such as digestion, increasing the heart rate and blood sugar levels, and dilating air passages. A cortisol surge at this time also helps reduce the pain and swelling may that occur with an injury, so that the bird can escape from predators. In the second stage, called the “stage of resistance”, the initial adrenaline surge subsides, but blood cortisol levels remain high for as long as the stressor remains in the bird’s environment, keeping the body ready for action. In the third stage, called the “stage of exhaustion”, the high cortisol levels start to take their toll, suppressing the bird’s immune system and allowing dormant infections to become active, or predisposing the bird to infection by opportunistic organisms. It can also effect the cardiovascular and gastrointestinal systems, and inhibit reproduction. Birds that have been stressed for prolonged periods may develop changes in their feather growth known as “stress bars.” These are evident as lines on the feathers perpendicular to the axis of feather growth.
There are many factors that can cause stress in a bird’s life, and in order to limit stress, one needs to know what causes it. The following is a list of some common stressors, and what you can do to prevent them from becoming a problem.
1. Health – An underlying disease process is a common cause of stress. Remember that pet birds have the instincts of wild animals, and will try to hide illnesses for as long as possible. Underlying infections or organ disease will tax a bird’s reserves, and any other added stressor might allow the bird to succumb to the disease. Frequent gram negative or yeast infections may be an indicator of a more serious underlying disease process or chronic stressor that results in immune compromise. For this reason, regular (annual) veterinary check-ups are essential for your bird’s good health. Organisms such as chlamydia (psittacosis), polyomavirus, and PBFD can be carried asymptomatically in otherwise healthy birds, and can emerge to infect other birds when the carrier is stressed.
2. Diet – Malnutrition is probably the most common cause of illness in pet birds. Birds that do not eat a well-balanced diet often develop nutritional deficiencies that can directly and indirectly affect the immune system. Birds that eat an all-seed diet are not getting enough of 23 different essential nutrients, but it is usually the lack of vitamin A which causes the first problem. The lack of vitamin A causes changes in the mucus membranes which predispose a bird to respiratory infections. Other nutrients are essential in normal liver function, bone growth, metabolism, etc. The chronic changes caused by these deficiencies result in underlying disease processes that act as stressors.
3. Housing – An inappropriate cage size or style will add stress to a bird’s life. Some examples of this would be a large parrot in a small cage, free-flying finches in a tall skinny cage, or a small parrot in a cage with wide bars. Too many perches and toys, or not enough, can both cause problems, depending on the bird. A new toy should be introduced gradually so as not to scare a shy or introverted bird. Overcrowding in a cage not only causes stress, but increases cage aggression and disease transmission. A dirty cage, in which food waste and feces have been allowed to collect, not only puts the bird at a health risk for opportunistic bacterial and fungal infections, but also adds stress.
4. Environment – A bird’s environment is one of the most common sources of stress. Some environmental stressors are sudden temperature changes, loud or threatening noises, odors, cigarette smoke, threatening pictures, or alterations in the light-dark cycle. Other pets in the household can easily stress a bird, from the cat sitting on the cage, to the dog’s barking, to the loud squawking of the macaw in the next cage. Birds housed in outdoor aviaries may be harassed by wild animals, and household pests, such as rats or mice, will also threaten a bird. Also, anything that disrupts the bird’s normal sleep pattern can act as a stressor.
5. Reproduction – Courtship, nesting, egg-laying, incubation, and raising young are all added stressors to a birds normal routine. Limiting other stressor during these periods is critical to successful breeding.
6. Change – A change in a bird’s routine or environment doesn’t necessarily have to be bad to add stress. Sometimes simple changes, such as moving the cage from one side of the room to the other, can be a monumental change for an insecure bird. Other things that cause problems include new people or animals in the household, moving, dietary changes, or anything novel or unfamiliar.
7. Limiting Stress – Just like in humans, there is rarely a time when there is no stress in a bird’s life. Since stressors tend to have a cumulative effect, limiting stress when possible is important for a bird’s health. For instance, don’t attempt a dietary change while treating a bird for a bacterial infection or moving it to a new cage. Don’t take your bird to visit your mother on the same day that it goes to the vet for a wing trim. Don’t let strangers tour your aviary when your parrots are attempting to nest. Minimize stress when and where possible, and you will find that your birds will be healthier mentally and physically.