LIFE HISTORY AND MEDICAL MANAGEMENT OF MACAWS
Susan L. Clubb, DVM
Loxahatchee, FLorida, USA
Macaws have long been admired and coveted by collectors, zoos and aviculturists for their
exquisite form and bright flashy colors. Macaws are highly adaptable, hardy and easy to keep
making them ideal for exhibition or breeding. They are relatively long lived although estimates
of the life span of macaws are often exaggerated. They are also very intelligent and relatively
easily trained to perform, making them a frequent choice for trained bird shows. This further
increases interest in macaws by observers. And finally most species of macaws breed well in
captivity. They are easy to maintain and adapt to a variety of diets. This combination of traits,
make macaws frequent favorites of parrot enthusiasts worldwide.
Macaws are a relatively old group of parrots taxonomically and some species are highly
specialized in their feeding habits, a trait which has led to the decline of a number of species.
Two macaw species are known to be extinct; Ara autocthones, the St Croix Macaw, is known
only from boney remains, and Ara tricolor, the Cuban Macaw was last recorded in 1864.
Anodorhynchus glaucus, the Glaucus Macaw, is believed by most ornithologists to be extinct
despite the occasional rumor of a bird or birds in captivity. Extinction of this species is believed
to be related to foraging of herbivores, primarily cattle, which over time halted maturation of
palm trees, which produced the fruit upon which the species was dependent. It is also believed
that the species, as other Anodorhynchus were likely in a natural decline associated with
changing habitat and over specialization prior to the introduction of domestic livestock to South
America. Ara sp. are for the most part more adaptable and hardy, able to withstand adaptive
pressures.
The Extant macaws are:
Ara ararauna
Blue and Gold Macaw
Ara glaucogularis
Blue-throated Macaw or Caninde Macaw
Ara militaris
Military Macaw
Ara ambigua
Buffon's Macaw
Ara macao
Scarlet Macaw
Ara chloroptera
Green-winged Macaw
Ara rubrogenys
Red-fronted Macaw
Ara auricollis
Yellow-collared Macaw
Ara severa
Chestnut-fronted or Severe Macaw
Ara manilata
Red-bellied Macaw
Ara maracama
Illiger's Macaw
Ara couloni
Blue-headed Macaw
Ara nobilis
Red-shouldered or Nobles Macaw
<p>
Anodorhynchus hyacinthinus Hyacinth Macaw
Anodorhynchus leari
Lear's Macaw
Cyanopsitta spixii
Spix's Macaw
BREEDING MANAGEMENT
Most macaw species are well represented in aviculture and breed with some regularity. Of the
Ara species all except A manilata and A couloni are well established in aviculture in the United
States. A manilata has been frequently imported but has not adapted well to life in captivity. It is
exceedingly shy and in the wild has a limited diet making it relatively difficult to acclimate. Its
raspy vocalization is also unpleasant. Ara couloni is relatively unknown in captivity due to its
limited and remote range, although it is reported to be locally plentiful. The hyacinth macaw is
also well represented in aviculture but is not as reliable a breeder as the Aras.
No single formula exists for successful aviculture. Some breeders utilize very large flight cages,
(example 8' x 8' x 16') allowing the birds ample room for flight. The majority of breeders in the
South Florida area utilize suspended caging, varying in size, however a realistic average may be
4' x 4' x 6' to 4' x 6' x 7'. I have seen macaws breed very successfully in very small cages
measuring only approximately 3' x 3' x 6 feet tall adjoining a wall with a nesting barrel on the
other side. Macaws bred for many years at Parrot Jungle and Gardens in Miami, F1 in stall type
cages, nesting on the floor behind a small partition. I know of hyacinth macaws, which have
bred in a pet shop window and blue and gold macaws, which have bred in a standard pet macaw
cage designed for the home. If a pair of macaws wants to breed and are provided a nesting site,
success can be achieved. Conversely, if a pair has a poor pair bond, are unhappy with their
environment, or are recalcitrant to acclimation to captivity, they may never breed.
Macaws breed primarily in the late spring and summer in Florida, however the occasional pair
will breed almost yearround. Clutches range from 1 to 6 eggs, usually 2 to 4. Productive pairs
generally produce 2 - 3 clutches in a year. The chances of producing more clutches, or eggs per
clutch are greatly enhanced by removing eggs from the nest for artificial incubation.
Incubation period for macaws is usually thought of as being 26 to 28 days. According to recent
research the average incubation period ranges from 25.1 days in Yellow collared macaws to an
average of 26.9 days for hyacinth macaws. Within each species the range for incubation period
generally varies by several days and in Blue and Gold macaws hatchings have been reported as
early as 23 days and as late as 30 days. With new incubation technology (Grumbach incubators),
incubation of macaws from day 1 can be very successful, however previously approximately 2
weeks of natural incubation was recommended to prevent early embryonic mortality.
Pip time, the time from the initial pip of the egg until the chick is free of the egg, is also variable
among species and ranges in duration. The majority of macaws pipped for 2 days(25% to 63%
depending on the species) prior to hatching. A small percentage hatched after only 1 day pipping
(0 to 17% of eggs depending on species) while some chicks pipped for 4 days.
Embryonic mortality in macaws, as in any avian species, is greatly influenced by incubation
techniques. Embryonic mortality in the nest is typically associated with improper parental
incubation, or inclimate weather. Macaws are very protective of their eggs and may break them
in an attempt to prevent removal. Some macaws will habitually eat their eggs.
Common causes of embryonic mortality in artificially incubated eggs include; cracked or
traumatized eggs, maiposition, and poor eggshell quality. The shell of macaw eggs, are unlike
those of other psittacine species, having a very smooth, shiny surface, which appears as if it was
polished. Poor shell quality is most often seen in aged macaws, but is occasionally associated
with malnutrition or oviduct or shell gland infections.
CHARACTERISTICS OF MACAW HATCHLINGS
Macaw chicks are altricial and have very little, fine first down at hatching. The eyes and ears
closed. Some beak pigment is usually present at hatching, but the chick is otherwise pink. A
large pip muscle is present which may be considered abnormal to the inexperienced observer.
Beak pads (rictal pads) are present on both the mandible and maxilla. Hatchlings have little
muscle control and recumbent posture. Hatchlings can often be identified to species by the color
of the first down and amount of beak pigment present (For example, first down is pink in scarlets
and greenwings, white in blue & golds and grey in militaries).
DEVELOPMENT OF MACAW CHICKS
Growth and development of large macaw species is relatively slow in comparison to other
psittacine species. The eyes open at 15-27 days of age and the ears open at 16-35 days. The
second down feathers emerge at between 7-18 days of age and is completely emerged and
mature at 45-80 days. Body covert feathers form under the skin (in the same feather follicles as
the first down) and begin to emerge at 18-30 days of age. Covert feathers mature at 70-150 days
of age. Primary feathers emerge at 25-35 days and are fully mature at 75-150 days. Tail feathers
emerge at 21-35 days and are the last feathers to mature at 90-160 days. Development is more
rapid in smaller species.
The weaning age of captive bred macaws usually coincides with or precedes maturation of flight
and tail feathers.
Weaning age is approximately:
Hyacinth, Greenwing, Buffons
135-150 days
Blue and Gold, Scarlet, Military
110-120 days
Red-Front
Severe, Yellow Collar, Red Belly
75-85 days
A macaw chick grows rapidly to a peak weight prior to weaning; it then tends to plateau and
loose weight (up to 10 -15% normally) prior to weaning. The peak weight is usually within the
range of normal weight for adults of the species.
MAXIMUM WEIGHT MACAW CHICKS (PRIOR TO WEANING)
Hyacinth
Greenwing
Scarlet
Blue and Gold
Military
Caninde
Red Front
12 weeks
10 weeks
8 weeks
9 weeks
8 weeks
10 weeks
9 weeks
1235
1185
930-1075
925-1050
750-1035
670-830
415-525
AVERAGE ADULT WEIGHTS OF MACAWS
Hyacinth
Greenwing
Buffon's
Blue And Gold
1200-1500 grams
1000-1450 grams
1050-1500 grams
850-1300 grams
Scarlet
Military
Caninde
Red Front
850-1200 grams
750-1050 grams
675-1000 grams
380-550 grams
COMMON PEDIATRIC PROBLEMS OF MACAWS
Macaws are among the more difficult of psittacine chicks to hand rear. Stunting, or failure to
thrive, is a common problem in macaw chicks and presumably is associated with nutrition.
Macaws adapted to a diet consisting primarily of palm fruits, which are high in fat. likewise it
appears that macaw chicks require higher levels of fat, and perhaps lower levels of dietary
protein than cockatoo or amazon chicks. Alternatively macaw chicks could simply have a very
high caloric requirement. Current research in progress will address this question.
Some diseases and disorders are seen frequently in macaw chicks including candidiasis and
enteric bacterial infections. Chicks receiving an adequate balanced diet and kept under sanitary
(not sterile) conditions seldom succumb to infection.
A number of disorders appear to be associated with the stunting syndrome. Stunted chicks can be
recognized by inadequate growth as indicated by inadequate body weight or daily weight gain.
Stunted chicks will appear disproportionate with the head relatively large in proportion to the
body. The wings, legs and toes are thin. Delayed ear opening, delayed eye opening and opening
of the eyelids high over the orbit are common observations. The emergence of feathers is delayed
in stunted birds and characteristically abnormal patterns of feather emergence can be seen in
feathers, which emerge on the top of the head. If discovered early and husbandry or disease
problems are corrected, stunted chicks can reach their full genetic potential. Otherwise chicks
will succumb, have prolonged weaning or weaning crisis, or remain undersized at maturity.
Lateral deviation of maxilla, often referred to as scissor beak, is a developmental abnormality,
which is more common in macaws than in other psittacine species. This abnormality is seen
almost exclusively in hand raised macaws and may be associated with the way in which the
handfeeder handles the bird and manipulates the beak during feeding. In one study the incidence
of lateral beak deviations was reduced dramatically when the calcium level and
calcium/phosphorous ratio of the diet was corrected. Tiny irregularities of the occlusal surface of
the mandible have been observed in small chicks (2 to 3 weeks of age) and may be responsible
for the initial deviation of the maxilla. These irregularities should be trimmed with cuticle
scissors. Other theories include response to trauma associated with always feeding on the same
side of the beak. If detected early, prior to calcification of the maxilla, most deviations can be
corrected by physical therapy. In cases which are not corrected early, or which fail to respond to
physical therapy, means of applying "orthodontic" devices have been developed and are being
applied with a good degree of success.
Crop atony, overstretching of the crop, occurs when excessive volumes of food are fed to chicks.
Stunting also predisposes chicks to crop atony as chicks have general loss of muscle tone. The
fear of overstretching the crop often inadvertently results in stunting, as aviculturists may be
afraid to feed chick adequate volumes of food resulting in inadequate caloric intake.
Splay leg deformity occurs most frequently in parent-raised chicks, which are raised on a diet,
which is insufficient in calcium or has an improper calcium/phosphorous ratio.
Hepatic hematoma is a traumatic injury in which the tissue of the liver is ruptured and
hemorrhages under the capsule of the liver. The causative trauma appears to be a result of
picking up the chick with the fingers encircling the chicks’ body with pressure from the finger
tips being exerted on the surface of the liver. Macaw chicks are more frequently affected and this
trauma usually occurs at 2 to 4 weeks of age. At this age macaw chicks are clumsy and they
struggle and wiggle excessively when they are picked up. An undefined nutritional imbalance
may predispose chicks to this syndrome.
Bite injuries from siblings occur when several chicks are housed together. Chicks attempt to feed
from each other and bite wounds may damage the wall of the maxilla as well as the soft tissue
inside the mouth and around the tongue.
Esophageal and Pharyngeal Punctures occur when feeding implements puncture the mucosa and
formula is deposited into the soft tissue. Macaw chicks feed aggressively and when in a feeding
frenzy they may jump against the feeding implement. Pharyngeal punctures occur in chicks fed
with syringes. Esophageal punctures occur in chicks fed with tubes.
Macaw chicks are sensitive to over dosage with vitamin D3 with resultant, often fatal
calcification of soft tissue, and in some cases visceral gout. Formulated diets should not be
supplemented with additional vitamins.
Feather chewing is common in chicks immediately prior to, during or after weaning. Chicks
which, are kept together in groups, are most likely to chew their feathers and typically chew the
flight and tail feathers. Chicks must usually be separated to avoid feather destruction. This
behavior is especially common in red fronted macaws.
MAJOR INFECTIOUS DISEASES OF WILD-CAUGHT IMPORTED MACAWS
Thousands of macaws were imported into the United States during the 1970's and 1980's.
Imports were primarily from Guatemala, Honduras, Bolivia and Guyana. In working with
imported macaws for a period of over 11 years, a number of disease processes were observed
which appear to be significant in macaws. Some of these diseases continued to be problems in
aviculture.
Macaws are basically hardy and in comparison to other psittacine species they are relatively
resistant to many disease problems. For example macaws are relatively resistant to Pacheco's
parrot disease, as compared to Amazons, but from extensive clinical observation and some
limited laboratory work, do not appear to develop a carrier state.
Macaw wasting disease or proventricular dilatation syndrome (PDS) is one of the most
problematic diseases of macaws. Despite extensive investigation at a number of universities both
in the United States and in Europe, the exact etiology for PDS is still unknown. Clinical and
epidemiological evidence indicates that the causative agent is a virus. Clinical signs include
proventricular and ventricular dysfunction and dilatation, anorexia, regurgitation, passage of
whole digested seed in the stool, weight loss and emaciation. A paramyxovirus or a togavirus
(possibly similar to Venezuelan Equine Encephalomyelitis) have been suggested as etiologic
agents. At the University of Florida a varus was isolated (the avian serositis virus) which
produces experimental lesions that are similar to those described with PDS. It has been suggested
that a virus may induce an autoimmune reaction that would be responsible for the lesions
observed. The causative virus would no longer be present and corticosteriods may be helpful in
treatment.
Papillomatosis - Cloacal, oral or internal papillomas appear frequently in macaws, especially in
green-winged macaws. Affected mucosa may appear rough or in advanced cases red or pink
cauliflower like masses will appear inside the cloacal or oral cavities, or protruding from the
cloaca. Birds may strain to defecate, or have a foul odor associated with bacterial proliferation.
Most cases can be diagnosed on physical exam. Confirmation is by biopsy. Internal lesions may
be found in the esophagus, crop, proventriculus and ventriculus. There appears to be a
correlation with neoplasia of the bile ducts, especially in Amazons. Venereal transmission has
been suspected, but not proven. Lesions can regress and reoccur periodically. Transmission by
direct contact between birds has also been suggested. However, I have known of unaffected
birds, which have been caged with and bred with an affected bird for years without developing
papillomas. Various treatments, including cryosurgery, chemical cautery (with silver nitrate) and
autogenous vaccination have been tried with varying success.
Psittacine Pox - Psittacine pox is a common and devastating disease of imported Amazons. Adult
macaws are naturally resistant to pox however chicks will develop the classic diphtheritic (wet
pox) form of the disease. Affected birds have lesions in the eyes, mouth, toes and often in the
wall of the beak.
Bacterial infections - Salmonella typhimurium and enteric gram negative bacterial infections
were often found in imported Amazons and less frequently in macaws, however occasional
outbreaks of disease were observed. Antibiotic resistance was common as birds frequently came
in contact with contaminated water.
Parasites were routinely found infesting wild-caught macaws. Lice, which were resistant to some
commonly used insecticides, were often found on imported macaws. Capillaria, roundworms
and coccidia were also occasionally found.
MAJOR DISORDERS OF CAPTIVE MACAWS
A few of the diseases which were important in imported macaws are continuing the be problems
in macaw aviculture, especially proventricular dilatation syndrome and papillomatosis.
Feather plucking can be very problematic in macaws and in most instances appears to be
behavioral in origin. Macaws are highly intelligent and pet birds require enrichment to prevent
boredom. Macaws will also pluck feathers when sexually frustrated and many will cease
plucking if allowed to breed.
Feather chewing, primarily of the flight and tail feathers is common in young birds and can
become habitual continuing into adulthood. It is especially common if a number of birds are
housed in a relatively small enclosure together. Birds must be separated in order to stop the
feather destruction.
Pancreatitis occurs with a higher frequency in macaws than in most other psittacine species.
Pancreatitis in most species is associated with obesity, however obesity is not a common
problem in macaws. In acute pancreatitis the pancreas becomes inflamed and activation of
pancreatic enzymes in and around the pancreas results in tissue necrosis, hemorrhage, peritonitis
and shock. Serum amylase is greatly elevated. Vomiting and diarrhea may be seen. Food should
be withheld for initially while treating with fluids and antibiotics.
In chronic pancreatitis, the affected bird may loose the secretory function of the pancreas and
require supplementation of digestive enzymes in the diet. Recovered birds should be fed a low
fat diet.
Obesity is uncommon in macaws but does occur occasionally. Macaws appear to need or tolerate
a higher level of dietary fat than other psittacine species.
Mated macaws become very territorial and can be very aggression if housed in groups other than
in pairs. If a number of birds are housed together and two form a strong pair bond and become
interesting in breeding they will often attack and kill their cage mates.
BREEDING LIFE SPAN OF MACAWS
Breeding records for macaws from Parrot Jungle and Gardens, in Miami, FL, were analyzed in
order to determine the reproductive life span of macaws in the collection. These records spanned
over 50 years. Analysis of these records indicated that the macaws at Parrot Jungle breed
between 4 and 35 years with the most productive years being 8-25 years of age.
ESTIMATING THE AGE OF MACAWS
A number of physical characteristics can be used to estimate the age of macaws. Eye Color is
one of the most helpful characteristics. The color of the iris changes in most species in a
somewhat predictable manner, however variations do occur frequently. In all species the iris of a
chick in black, then brown to grey. At approximately 1-3 years of age the iris turns whitish to
yellowish. Around 10 years of age the eyes become more golden in color and become richer gold
with age. As the birds become aged the iris becomes thin and a ring of dark grey appears around
the pupil, which is the black of the retina visible thru the thin wall of the iris in an old bird.
In general the feet and beak tend to become scalier with age. The texture, elasticity and quality of
facial skin can also be evaluated along with eye color in trying to estimate the agr of a macaw.
Behavior is also an indicator of age. Young birds are playful, friendly, inquisitive and often
destructive. Mature macaws usually become aggressive as they become interested in mating and
raising young. Older macaws become calm, often placid and tame, making very nice pets.
FEEDING MACAWS
Most macaw species are very adaptable in their feeding habits and will accept a wide variety of
foods once acclimated to captivity. Historically macaws were fed diets consisting primarily of
sunflower seeds, which are high in fats and proteins but deficient in calcium and some vitamins.
These high fat seeds are similar in composition to the high fat palm nuts, which make up as
major component
of the diet of wild macaws. As aviculturists became more aware of the potential for dietary
deficiencies when feeding only seeds, diets have become more varied typically with the addition
of fruits, vegetables, nuts, berries, melons, breads, pastas, and vitamin/mineral supplements.
Many macaws are being maintained very well on formulated extruded or pelleted diets. For
growth, maintenance and reproduction macaws require a higher caloric intake than some other
species such as cockatoos and Amazons in order to maintain good weight and condition. Macaws
should be given a varied diet for psychological enrichment.
AGING CHARACTERISTICS OF MACAWS
A group of aged macaws at Parrot Jungle and Gardens in Miami FL, were examined annually for
five years in order to study the effects of aging and provide insight into longevity of macaws. Of
the 57 birds in the study, 25 hatched at Parrot Jungle and remained there for their entire lives. All
birds in the study were at least 25 years old.
The oldest bird at Parrot Jungle, a military macaw, was euthanized 2 years ago due to frequent
and severe seizure activity. This bird was one of the original birds imported in 1936 for the
opening of the park and was therefore, at least 57 years old. He had been blind and had a chronic
neurologic disorder for many years. The onset of these disabilities was not recorded.
A decline in breeding potential was found to occur at approximately 35 years of age, which
coincided with the early appearance of degenerative diseases. Early cataract formation was
evident in many birds. The birds became more sedentary, had some loss of muscle tone and
changes in skin texture and quality.
By 40 years of age muscle wasting and weight loss was generally evident. These birds would
rarely fly but were still active walking around and interacting with the public in search of a
handout. Most birds had general joint stiffness or arthritis and some birds had difficulty moving
especially in cold weather. Facial skin was thin and many birds had numerous skin blemishes.
By 45 years of age many birds showed signs of musculoskeletal degeneration, possibly similar to
osteoperosis evident by a twisting deformity of the carpus and toes and stooping posture. Fortyfive year old birds had a high incidence of neurological disease, stroke, and blindness. Few birds
survived to 50 and those that did were generally debilitated and sedentary and most were blind.
Feather pigmentation was typically unaffected although feather condition and luster often
declined in birds in their mid to late forties.
COMMON OLD AGE DISEASES OF MACAWS
A number of common degenerative disorders occur frequently in macaws. One of the most
common and potentially important is cataract formation. Cataracts were present in most birds by
35 to 40 years of age and without surgical intervention most birds were totally blind by 45. Many
birds developed an immunological response to the cataractous material in the lens resulting in
inflammation, which destroyed other structures within the eye, ultimately resulting in blindness.
The onset of cataracts and subsequent reduction in vision would likely limit the life span of
macaws in the wild. Cataract surgery was done in 13 eyes of eight birds. These birds were
selected for surgery because of visual impairment or inflammation within the lens, which would
have resulted in loss of the eye if left untreated. In general results were good and for most birds
vision was restored.
Degenerative joint disease observed in macaws may be similar to arthritis of humans and further
investigation is needed. Stiffness of the hocks, elbows and carpus were most common.
Pancreatitis appears to be more common in older macaws despite the fact that most older
macaws are thin. Some birds had recurrent bouts of pancreatitis and dietary changes, from a
seed, fruit and vegetable diet to a pelleted diet resulted in much improved condition. Stroke and
other degenerative neurological diseases were especially common in birds over 40 and were
often accompanied by classical one sided paralysis or paresis, facial paralysis (drooped lids, etc),
and tilting or trembling of the head. Neoplasia was less frequent than degenerative disease.
Degenerative kidney and hepatic disorders (cirrhosis) was seen. Congestive heart failure,
atheroschlerosis and acute infarcts similar to heart attacks were also seen.
CONCLUSION
Macaws are long-lived birds and have few natural predators. They provide parental care for their
young for a period of at least four months, making it unlikely that they would raise multiple
clutches of chicks annually in the wild unless the first clutch was lost. Reports on the
reproductive success of wild macaws indicate that they may not breed every year and often rear
only a single chick. 3. Theoretically species which have a low reproductive rate can maintain
stable populations if they have a long reproductive life span. While field studies at Manu and
other sites are enhancing our knowledge of the biology of wild macaws, by observation and
record keeping we can still learn much about maintenance of populations of macaws in captivity
as a possible resource for the future.
References
1. Clubb, S.L., S. Wolf and A. Phillips, Psittacine Pediatric Medicine, In Psittacine Aviculture,
Perspectives, Techniques and Research, Schubot, R.M., K.J. Clubb and S.L. Clubb, A
publication of Avicultural Breeding and Research Center, Loxahatchee, Fl, 1992.
2. Clubb, S.L., and K.J. Clubb, Reproductive Life Span of Macaws at Parrot Jungle and Gardens,
Miami, In Psittacine Aviculture, Perspectives, Techniques and Research, Schubot, R.M., K.J.
Clubb and S.L. Clubb, A publication of Avicultural Breeding and research Center, Loxahatchee,
Fl, 1992.
3. Clubb, S.L. and L.G. Karpinski, Aging in Macaws; JAAV 7(1); 31-33, 1993.
4. Gerlach, H., Viruses, In Avian Medicine, Principles and Application, Ritchie, Harrison and
Harrison, Wingers Publishing, pp. 862-940, 1994.
5. Munn, C.A., Macaw Biology in Manu National Park, Parrotletter 1: 18-21. 1988.