Fall is the time of change — particularly along the northern tier in the United States.It is a time of vibrant color changes in the trees and plants, the migration of birds, cooler temperatures, and it is when daylight hours reduce dramatically. While we often think about how autumn affects us, a change of seasons also brings out changes in our pet birds.
With fall’s cooler temperatures, we often turn on our furnaces. Along with the sudden burst of warm air, there can also be a burst of spores and dust, which pose respiratory hazards for our birds. The very anatomical features that allow birds to fly, an upper and a lower respiratory tract, also predisposes pet birds to respiratory problems with molds, dust and bacteria. Air flows through a much larger percentage of birds’ bodies, compared to mammals, so mold and dust affects birds more.
Upper Respiratory Tract In Birds
The upper respiratory tract includes the cere, the area around the top of the upper beak. It may be feathered or unfeathered, depending on the species of bird. The nares, or nostrils, are located within the area of the cere and may be shaped abnormally as a result of chronic upper respiratory infection. Air moves through the nares into the nasal cavity.
The nasal cavity in most parrot species is divided by a nasal septum. Within the lateral walls of the cavity are highly vascularized nasal “conchae,” which are scroll-like cartilage covered with a nasal mucosa. There is also the infraorbital sinus, which drains through the top of the middle nasal concha. This area is sometimes plugged by mucopurulent material (pus and mucus) during respiratory infections, which causes swelling under the bird’s eye. The infraorbital sinus extends into the upper and lower beaks, around the eye and ear and also connects with the cervicocephalic air sac at one end, thereby creating another area for air (and dust and mold) to flow.
Lower Respiratory Tract In Birds
A bird’s lower respiratory tract starts at the tracheal opening and includes the airways and the gas exchange surfaces. This includes the larynx, trachea, syrinx (“voice box”), primary bronchi, the parabronchi (small tubes within the lungs that transport respiratory gases), air capillaries of the lung parenchyma, and paired air sacs. The interconnected air sacs and lungs allow for much greater oxygen exchange than in mammals. Interestingly, inspiration is active in both mammals and birds, but expiration is an active process in only birds. So birds need to move their chest wall for both inspiration and expiration.
Gas exchange occurs primarily in the walls of in the air capillaries, which are the avian equivalent of alveoli. The blood-gas barrier of birds is similar anatomically to that of mammals in that it consists of an endothelial capillary cell, a common basal lamina and an air capillary epithelium of squamous cells. The difference is that the blood-gas barrier is much thinner in birds than in mammals. The diameter of the air capillaries of birds is much smaller than that of a mammalian alveolus, allowing for a much larger number of air capillaries in a given space when compared with mammals. It is this small diameter that poses a problem when birds get sick, as they tend to take on fluid into their lungs.
The result of all these anatomical adaptations is that birds are much more efficient than mammals in capturing oxygen and removing carbon dioxide. However, birds can accumulate fluid in the lower respiratory tract with infections.
So, with the change of seasons, the goal is to minimize the effect of on-and-off cycles of the furnace on our pet birds. Clean your furnace filters, add humidity to the air, and keep your birds away from drafts. Stay alert to your pet birds’ health and behavior. Is it staying active and breathing normally? Are there any plugs (debris) visible in the nares (“nostrils”), or are they clear? A pet bird might be seriously ill if its feathers are fluffed, and its tail bobs up and down with each breath it takes for extended periods, which warrants a call to your avian veterinarian.
Reduced Daylight Triggers Hormones Changes
With fall comes reduced daylight, which can also cause changes in your bird’s behavior. Shorter daylight hours can turn off sexual behavior in some species of pet birds and turn it on in others.
While longer days stimulate reproductive behaviors and nest-building behaviors in many pet birds, such as Amazon parrots and conures, cockatiels exhibit these behaviors in the fall. In captivity, macaws often breed in December and January (often with a secondary spike in July), followed by African grey parrots and large cockatoos. Artificial lighting during fall and winter confounds the timing of reproductive activity, so it’s difficult to separate natural behavior from induced behavior in pet birds.
To reduce reproductive behaviors, consider how reproductive triggers occur in the wild and how we sometimes create similar triggers without meaning to. For example, when we cover our pet birds’ cages we create what some birds might view as a palatial nest-box. Feeding a large variety of foodstuffs (especially foods high in protein and fat) creates something similar to a rain-forest smorgasbord that signals the time is right for reproduction.
With long, dark nights, we often sit on our couches and watch television, sometimes petting our feathered friends. However, it’s important to know that your pet bird might interpret excessive petting as a signal that you are its mate, which can bring out reproductive behavior, especially if you pet under the wings or down the bird’s backside. Instead, only pet your bird’s head/cheek feathers.
Fall is a time of change that stirs our senses. Autumnal changes and indoor living can affect the respiratory system of birds through molds, dusts and drafts, and alter the amount of light, causing changes in reproductive behavior. With care and attention, we can get our birds through the fall season in fine form.