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Back to Rhea Articles RheaCraig Hopkins Greater or Common Rhea Rhea Americana Order Rheiformes Rheas are natives of the grasslands and brushy regions of
South America. They are found in
eastern and central Brazil, Paraguay, Uruguay, Bolivia, and Central Argentina. Rheas are members of the zoological superorder that also
includes the ostrich, emu, cassowary, and kiwi, which are collectively known as
ratites. All of these birds share
in common small or rudimentary wings and a breastbone with no keel.
The adult birds are a slate gray color with black on the head, neck, and
between the shoulders. The male has more black coloration between the shoulders at
the base of the neck. Rhea can also
be white in color and sometimes even pure white.
This color mutation has been propagated in captivity and is now quite
common. The adult birds stand about
5 feet tall and weigh between 60 and 70 pounds.
The male is the larger of the two sexes. Rheas are polygamous-polyandrous, which means that the
roles of the males and females are reversed.
The male builds the nest, incubates the eggs, and rears the chicks once
they are hatched. The female’s
only role is to lay the eggs. When
spring arrives, the males become aggressive towards one another and strut around
with the feathers on their heads, necks, and chests raised so that they appear
larger than they really are. During
this time, some males will become aggressive towards humans.
The male can be handled by grabbing him by the neck, just below the head,
and wrestling him around until he tries to flee. Once a male has obtained dominance, he will establish a
territory and begin to collect a harem of females. He will court the females by spreading his wings, bobbing his
head, herding the females around, and by making a booming sound, which sounds
like “uh hum”. The male will
mate with several females. It is
usually best not to exceed 5 or 6 females per male.
The females will lay their eggs near the male’s nest and the male will
roll the egg into his nest. The
nest is a depression in the ground that the male has scraped out and lined with
grass. If the male is allowed to
sit on the nest, the male will stop mating with the females once he has a clutch
of eggs. The females will then join
another male and start laying eggs for him. The females begin laying eggs near the end of April and
will lay every other day throughout the summer months. If the eggs are collected from the nest for artificial
incubation, a female may lay as many as 50 to 70 eggs.
If all the eggs are collected from the nest, the male may abandon the
nest and make a new nest in another location.
This can make collecting the eggs difficult if the birds are kept in a
large enclosure that has many places for the male to hide a nest.
A male will usually stay with the same nest if at least one egg is left
in the nest. This egg is collected
when another egg is laid in the nest. It
is a good idea to line the nest with additional hay or straw to keep the eggs
clean and dry. Incubation
The eggs are butter yellow when they are laid, but they
will soon fade to a cream color once incubation has begun. If it is done carefully, artificial incubation is much more
efficient than letting the male set on his nest. We incubate the eggs at 98.5oF and a wet bulb
temperature of 83oF. The
eggs will hatch after 34 to 40 days of incubation. The eggs should be candled after 14 days of incubation to
check for fertility. If an egg is
not fertile, it should be removed from the incubator so that it doesn’t spoil
and possibly contaminate other eggs in the incubator. Eggs should be placed in the incubator as soon as possible
after they are laid and no eggs should be held more than 7 days before
incubation. Eggs that are placed in
the incubator up to a week apart will often hatch at the same time if the eggs
are in shell-to-shell contact for at least the last two weeks of incubation. Hatching and Brooding
Many chicks can be saved by candling the eggs twice a day
starting on the thirty-third day and watching for signs that the chick has
broken the inner membrane. Once the
chick has penetrated the inner membrane, a hole is chipped in the shell where
the air sack is and the chick is allowed to continue the hatching process when
it is ready. Once the chick is
completely hatched from the shell, we leave the chick in the incubator until he
is strong enough to stand on his own. This
usually takes about 24 hours. The
chicks are then placed in a brooder that has artificial turf on the bottom and
red infrared heat lamps handing above for heat.
The red bulbs help prevent the chicks from picking at one another’s
eyes while they are in the brooder. When
the weather is warm, we like to get the chicks outside on a mowed lawn as soon
as possible. This allows the chicks to exercise, to eat fresh grass, and
catch insects. A shelter and a heat
lamp should be provided for bad weather and at night. Feeding
Rheas are mainly grazers and consume large quantities of grass, clover, dandelions, and other broad-leaf weeds. They will also eat small eggs, insects, earthworms, and small snakes. For adult birds, we feed chunk dog food, a ratite pellet, and green leaf lettuce. During the breeding season, a laying mash is mixed with these other feeds. The chicks are fed a ratite starter pellet, turkey starter, or a gamebird starter. The chicks are also given leaf lettuce and they are put in grass lots as soon as possible. Back to Rhea Articles © 2005, Hopkins' Alternative LivestockWeb site designed and maintained by Lisa Hopkins |