. We modify environments, feeds, cages, genetics etc to lessen losses in captivity.
We modify lots of things to improve our chances of making a profit from the
Topics covered below - in order:
Behaviour changes - From the moment any
one decides to take a bird or animal from the wild, they are influencing the
future of those birds or animals. How the birds are captured influences
the survival rates and how they will be treated.
Pair selection Most people choose
which birds are paired to each other just by looking at the birds. Avian
veterinarians and experienced breeders will often select a pair using additional
parameters. Visual judgement often does not allow for a lot of valuable
traits that have allowed the species survive up to now. We purchase birds
by visual examination and price.
Human compatibility Birds that
have adapted to accept people around or in an aviary are the most likely to be
bred in the highest numbers. Birds that can be bred in an indoor cage are
the most popular and the birds that beginners often start with. Birds that
make good pets have the best chance of having a long term monetary value and
Libido Dictionary definition "The psychic drive or energy associated with the sex instinct". The natural instinct to breed. Birds are placed in close proximity in our aviaries. This can promote hostilities and aggression just prior to and during the breeding season. In young "teenage" birds the mating aggression may extend outside the breeding season. To eliminate hostilities between pairs, avoiding the possibility of injury between rival birds, we place the pairs in separate aviaries or cages. Rivalry between breeding age birds is a natural selection process to offer the next generation the best genes to survive in their environment. The birds with the strongest desire to breed, that have the necessary skills to build or find an appropriate nest, will generally be successful breeders. Unsuccessful birds may have to wait till the dominant birds leave or they may provide a "nanny" type service to assist the young of the successful breeders.
Placing birds in an artificial environment with the choice of only one partner may limit the chances of successful breeding. "Teenage" birds often will breed no matter what conditions they are placed under. After the raging hormone levels subside, the breeding rates often decline. As the birds get older, breeding results often become erratic and in some seasons no eggs may be laid.
The cost of additional aviary space and the cost of purchasing additional pairs may limit what a keeper can provide. Solo pairs often need some form of competition to stimulate good breeding results.
Some birds such as Red crested Cardinals prefer no competition and like to be the only pair of their species in the area.
Some macaws like to be in a "group" of about 4 or 5 pairs. They do not have to be in the same aviary. Once the population exceeds a given aviary complex density (often 5 pairs) the birds breeding success declines. If the density is too high, the need for a species to continue breeding may decrease or cease.
Some birds such as a pair of Shamas, may need to be separated during the non-breeding season. Cock bird and hen bird placed in separate aviaries that are out of sight of each other during the non-breeding season. These birds are gradually reintroduced to each other prior to the start of the next breeding season.
Some birds such as the weavers may breed in very close proximity to each other. In the wild, dozens of pairs may nest in the same tree.
Different birds have differing requirements to guarantee the long term
survival of their species. All bird keepers should try to provide the
environment and individual needs of each species to maintain the best breeding
genetic lines in our aviaries.
"Clucky" trait: Many of the exotic
species of quail have lost the desire to incubate their own eggs. These
birds are so prolific at laying eggs, poultry producers now produce vast numbers
of these birds for the restaurant trade and for domestic consumption. Many
species of exotic Quail should be classified as "poultry" and not as regular
aviculture species. How many Californian Quail are in our aviaries that
incubate and rear their own young? These birds are of little or no value
for the beginner bird breeder because beginners usually do not have the
equipment or skills to use incubators.
Original stock: How the original stock
was obtained may have determined the genetic and physical traits of aviary stock
we now keep.
Culling defective birds: Captive
birds are rarely culled due to physical, mental, disease susceptibility, or
behavioural defects. Can the bird be sent off for sale to a beginner or
Antibiotic resistance: Like the
problem with antibiotic resistance in human due to overuse or inappropriate
antibiotic use, the same problem is increasing in animals and birds. Over
use and unnecessary use of antibiotics must be avoided. Always abide by
avian veterinarian advice and do not rely on second hand amateur advice.
Over use or incorrect use of an antibiotic can reduce the fertility of a bird.
Breeding longevity Does the
longevity of breeding stock influence the genetic viability of future
bloodlines. The integrity of human reproduction declines as the age of the
parent approaches the end of the natural breeding years. Birds in the wild
rarely die of old age. Something will probably catch and eat it, or it
will be killed as a result of an accident long before old age is attained.
If the genetic integrity of the young is determined by the breeding age of
the parent, does the "breed till the birds drop" attitude help the survival of
Colour mutations: Is the loss of
the pure "normal" colour bird of concern to the long term survival of a species?
For a re-release back into the wild, the birds must be in the pure wild genetic
colour. A colour mutation is a abnormality or defect in the wild
population's normal genetic coding. Mutations rarely survive as the
phenotype state in the wild. The colour gene is still in some of the wild
population as a split or recessive trait. Also refer to the next topic.
Controlled environment breeding rooms:
Many birds in their natural environment are able to survive low temperature or
freezing nights then have to endure high temperature days. Desert
environments can provide these wide temperature variations along with wide
variations in humidity and rainfall. Indoor controlled environment
breeding rooms often are restricted to temperature variations of only a few
degrees. Humidity is modified and the lighting duration and intensity is
programmed to fine tolerances.
Food availability: Captive birds
have seed mix availably in adequate quantities at all times. Live foods
are often only given at breeding time. Cost of livefood versus the value
of the bird.
Obesity: Infertility and general
lack of general fitness is increasing in many species and is often the result of
being over weight or obese. Excess food intake along with restricted
opportunity for flying a reasonable distance, and the modified environment
contribute to obesity.
Austerity diets: Austerity diets
(or restricted feed intakes) during the non breeding season are promoted to keep
birds from gaining weight and stimulate the birds to breed when the normal diet
is resumed just before the start of the next breeding season.
Nest construction: Birds are now
offered the nest materials that are either cheap, readily available, left overs
from last season, "hand me downs" from other people, what the keeper "thinks the
birds need", what the retailers sell them, or the lucky ones that are given the
correct materials based on experience or from experienced breeders. The
lucky birds are given a variety of materials that allow the adult birds to build
a nest based on their natural instinctive programming.
In the wild the finch cock bird (particularly weavers and whydahs) may build part of a nest waiting for the hen to give her approval for the choice of nest site and the quality of construction. Some cock birds may need to part build 10 or more nests before the hen gives her approval and accepts the nest. In the aviary with a choice of only a few preformed artificial nests, this pre-selection and quality approval skills are minimized.
Finches no longer need to build a nest that is waterproof or weather resistant as polycarbonate roof materials and solid walls do a better job.
Species from the genus Estrilda (waxbills) often build a "cock's nest" above
the brooding chamber if the nest is built in the open in a natural setting.
If we give the aviary birds a timber nest box, a commercial wicker or wire
preformed nest the bird may not have enough space to build the top part, or
cock's nest chamber. If this was to continue for a number of generations,
that genetic line may loose the instinct or natural ability to build a nest
similar to the birds in the wild. Many commercial wicker finch nests have
a long tunnel entrance incorporated in the manufactured design. The bird
no longer needs to use their skills to build tunnel entrance. Preformed
nest boxes also minimize the need for the birds to build a quality outer nest
structure. Even the worst built nest in a rigid artificial frame will be
sufficient for a pair to lay and raise a clutch of young. The waxbills
usually build a nest on or close to the ground. In an aviary situation the
artificial nest is placed at a convenient height for the keeper to inspect.
Just another factor potentially effecting the natural nesting instinct.
Digestion micro flora: Many animals
and birds transfer some helpful "bugs" to their progeny during the feeding and
rearing period. Does the incubation of the eggs and subsequent handrearing
of the young limit the transfer of beneficial "bugs" and make those birds less
able to resist some avian pathogens?
Genetic availability: Are some of
the rarer birds kept as pet or companion birds. Is stock being held by
people who have no intention of breeding the rarer birds or keeping them as a
Sub-species identification: Very
few people cared about breeding true to sub-species level when birds were
imported. The result is a line of current birds that are a possible mix of
different nominate and sub-species. As long as the birds were similar the
breeders were happy. Even today most breeders have the same attitude.
Some parrots are a mix of 2 or 3 sub species whereas some finch species could be
a mix of 10 or more sub species. This has resulted in some species of
birds in Australia having a similar, but not identical, appearance to overseas
stock. The possible benefit is the provision of a wider genetic diversity
in the Australian stock.
Pet birds: Parrots - Parrots such
as macaws are becoming popular as pets by people are prepared to pay for these
exotic colourful birds. Does the removal of rare birds for pets damage the
genetic variability of the remaining birds? Pet owners often are prepared
to pay top price for the best bird and then place the bird in an environment
that will not allow that bird to have a mate or breed. Removing the best
birds from a low gene pool species can reduce the long term viability of the
Natural species song: Do captive birds retain their natural imprinted song? We place a pair of birds, usually finches in an aviary with a number of species of birds that they would never meet in the wild. Does the fostering by another species of finch such as a Bengalese, influence the song of the original bird?
Often one pair of a particular species is placed in an aviary with several
other species of birds. After the young are fully independent of their
parents, the young are removed to another aviary so the parent birds can start a
new clutch of eggs. The young are placed with another group of birds that
may not include their own species. Who will teach them the correct song or
mating call for their own species? Will they add components of other birds
song to their own? Many overseas visitors to Australian aviaries comment
that some of our birds "sound different" to their aviary birds.
Natural plumage colour: The rearing
of birds on a standard commercial diet may result in the loss of the intensity
of feather colour. Housing birds in indoor or fully covered aviaries may
also result in loss of plumage colour.
Secrets: Many breeders take their
knowledge to the grave. Lack of publication of accurate observations
impedes the next generation of bird breeders. Equally the non-publication
of things that go wrong or result in bad outcomes should be published. Why
should each generation be subjected to make the same mistakes. An outline
of the methods and materials should be described and this can be a starting
point for other people to review that data and possibly refine or redesign some
aspects of the initial attempt. The fear that is often used for the
keeping of "secrets" is - "If I tell people how to breed those birds, they will
have better breeding results and the extra birds will reduce the price of the
birds I sell". Not a valid argument.