CAPE PARROTS SUCCESS AND
DISASTER
by William Horsfield
Success
The rare indigenous Cape Parrot
(Poicephalus robustus)
has captivated my attention
since my adolescent years in
the Eastern Cape. As a ten year
old, I unsuccessfully tried
to sweet talk a single bird
out of an elderly couple who
had him in an antique bell cage
on their farm verandah outside
Knysna. Every school holiday
I would trek up to Rheedendal
and put on my boyish charm,
but to no avail. The bird had
been part of Mrs Coetzees' life
for 20 odd years and she would
hear none of my not so subtle
suggestions. Sadly for the parrot
Mrs Coetzee ate herself into
a heart attack and her not-so-grieving
husband took himself off to
Mauritius (with his wife's divorced
sister), leaving the poor bird
to starve to death.
I managed to obtain my own
pair of Capes some 14 years
later. Since then I gradually
managed to locate odd birds
and make up a number of pairs.
This proved increasingly difficult
with the inter-provincial permit
requirements for these indigenous
birds. Nevertheless after 8
years of perseverance I had
managed to set up 10 pairs of
Capes on permit with the then
Natal Parks Board.
In 1998 I was delighted to
raise 18 progeny, mostly parent
raised. I was especially glad
to have bred 2nd generation
birds form 2 tame 10 year old
hand raised cock birds bred
by the late Jack Ruff, as well
as from a 3 years old parent-raised
hen bred by Frank Hilton. These
birds made excellent parents
and their tameness enabled stressless
behaviour observation and nest
inspection a pleasure.
Although shy by nature, I have
had no problem in persuading
the adult birds to breed. The
aviaries used were our suspended
design 3.6m long x 1.2m x 1.2m
as well as some which were only
2.4m long x 1.2m x 1.2m. The
smaller aviaries were used for
rescue cases which could not
fly for various reasons; some
had survived being shot, some
were vehicle casualties and
others had permanent wing injuries.
All aviaries have a heavily
planted shrubbery (600mm separation)
on the outdoor section. Flowering
Tecomaria and Hibiscus as well
as Nandina sp are preferred.
The indoor section has no visual
barrier between adjacent pairs
except that created by the nesting
boxes. Birds are fed on the
same side as the nest i.e. indoors.
An aviary inspection door on
the bottom of each aviary is
also situated in the indoor
section. The birds perch above
human eye level on hardwood
fruit tree and softer eucalyptus
perches
A variety of wooden nests are
readily used including natural
hollowed syringa logs (approx.
250-350mm ID) vertical boot-shaped
boxes (approx. 400mm high x
300mm deep x 250mm wide) and
ordinary vertical boxes (approx.
400mm high x 250mm x 250mm).
Chipped eucalyptus and pine
are used as substrate which
the birds chew into small splinters.
Courtship involves loud vocalization
with birds flying rapidly and
repeatedly up and down the flights.
The cock bird drops his wings
and feeds the soliciting hen
a number of times while both
birds intermittently bob their
heads in a vertical plane and
raise their wings in an archangel
type display. The cock stands
on the hen's back while mating,
copulating vigorously and rhythmically
from alternating sides and all
the time balancing with drooped
wings. I have only ever observed
mating in the early morning
and late afternoon, when the
birds are particularly active.
3-4 pure white and usually
very rounded eggs are laid during
Autumn-Winter (April-May-June)
or during early summer (October-November)
at 2-3 day intervals, although
pairs may go down in any month.
Pairs will double and even treble
clutch if 15t and 2nd round
eggs are removed for artificial
incubation. Eggs are incubated
at 37.50C at sea level and because
of their round shape are inclined
to position themselves with
airspace facing upwards in incubators
which negatively affects embryonic
development unless harid turned
at least once daily. In my experience
moving carpet turning is preferable
to rollers in this species.
A typical egg measures approx.
23.5mm wide x 28mm long. Internal
pip to hatch is 48-72 hrs. pairs
left to raise their own young
will usually breed twice per
year. Unless the 1"' clutch
of youngsters is removed the
2nd clutch of eggs is likely
to be damaged by the youngsters
who still join the parents in
the nest. The breeding birds
however often start to chase
and harass their same sex chicks
if they want to recycle. Incubation
is by the hen alone and chicks
weigh typically between 9.5g
and 11g at hatch. The cock will
spend a lot of time with the
hen in the nest. Originally
wild caught cocks will spend
most of the time with the hens
in the nest during breeding,
although aviary bred cocks tend
to stand guard outside the nest
entrance.
Originally wild caught birds
usually remain shy and disappear
into the nests at the first
sign of human approach. Although
described as quiet, I have found
them to be quite noisy in the
early evenings, when they are
most active. The recognition
call is a short, shrill and
very high pitched whistle which
is in my opinion loud. The defense
and distress growl is similar
to Greys and is observed during
nest inspection. As with Greys,
if disturbed on the nest, they
will often try to burrow into
the nesting substrate. Chicks
are straightforward to handraise
and they thrive on Kaytee Exact®
from the egg. Like other smaller
Poicephalus they are fed on
their backs and although I feed
them upright, they are always
allowed to lie on their backs
to swallow until they roll themselves
over. I have successfully used
nominate Jardine's to foster
Capes.
Capes are covered in short,
slightly offwhite down at hatching.
This is replaced by a very dense
covering of pure white down
until they are feathered. If
pulled at 3-4 weeks they do
equally well on Avi-Plus~ Handrearing
Parrot with a tablespoon of
sunflower oil added per cup
of feed. Fledged chicks compete
with each other for feeding
by the adults and flap one or
both wings to fend off their
nest mates while soliciting.
I use 9mm ID seamless stainless
steel rings as Gapes are inclined
to play with their legbands
and will crush softer rings
onto their legs. Chicks are
banded when small pin feathers
appear on the wings.
Adults continue to dig and
reshuffle the nesting substrate
during the rearing process and
I replace this 2-3 times before
the chicks fledge. In our climate
Aspergillosis is always a worry
when shavings may become fouled
and mouldy and I certainly don't
want the birds chewing on this
material. It seems the adults
are trying to clean the nest
with this scratching behaviour.
This same behaviour occurs prior
to laying when the nest is being
prepared for breeding. It ceases
during incubation and commences
again once the chicks have hatched.
Birds, which do not feed their
chicks, may be encouraged to
do so by removing, feeding by
hand and replacing chicks for
the first week. By this stage
the strong soliciting noises
and movements of the hungry
chicks usually stimulate the
adults to feed them.
In many ways the birds are
behaviourally quite different
from the now separately it classified
Grey-headed Parrot Poicephalus
suahelicus (formerly subspecies
Poicephalus robustus suahelicus).
They are far more active and
the calls are noticeably different.
P. suahelicus, especially hens,
are steadier.
Adult Cape hens often have
coral pink colour behind the
cere. This may vary from none
to quite noticeable. Adult cocks
never do. Immature plumage resembles
the hen although juvenile males
have broader heads and heavier
beaks. Hens have shorter beaks
than cocks. The beaktip, as
with the ~ suahelicus, is very
sharp and should not be mistaken
as being overgrown. It is used
as an extraordinary leverage
tool.
Diet for Gapes at my breeding
facility is much the same as
for other African parrots. In
the wild the Cape is a habitat
feeder and they are almost totally
dependent on the Podocarpus
(Yellowwood) forest. They breed
in dead snags of these trees
and eat the oily berries. If
these seeds are mashed into
a pulp they resemble a thick
peanut butter type consistency.
A large variety of fresh fruit
and vegetables with an Avi-Plus
softfood and pelleted mixture
is fed in the morning. Raw beetroot,
corn on the cob and cooked sweet
potato are favourites. All nuts
are relished and given liberally
daily. A variety of soaked and
boiled legumes (as in a racing
pigeon breeding ration) as well
as soaked sunflower, wheat,
oats and barley are offered
for the lunch time feed and
cooked rice, pasta and cheddar
cheese are offered as treats
in the late afternoon when birds
are inspected for the last time.
Coconut shells, pine-cones
and marble sized stones are
provided for environmental stimulation
and are played with for hours.
Disaster strikes
In managing to stimulate the
birds to breed I was unknowingly
unleashing a chain of events
that would ultimately prove
to be a tragedy for me personally
but also a disaster for the
species. When my 1998 progeny
started dying for no positively
identifiable cause, alarm bells
rang loudly. Specialist veterinary
and pathologist cooperation
determined severe anaemia in
the affected birds. All organs
appeared morphologically normal
although kidneys were enlarged
in come birds. Blood parasites
were suspected of destroying
the erythrocytes (red blood
cells) yet repeated examination
of blood smears revealed nothing.
Appetite and resultant lethargy
and weakness. Advanced cases
produced faeces with yellowed
urates and development of respiratory
distress. Some cases produced
a slimy, clear vomitus. All
birds dosed into the crop regurgitated
various amounts of drugs and
nutritives over a matter of
hours. Nothing at all worked,
and although at times individual
birds seemed to improve, they
all ultimately died. There was
at no time any feather or plumage
abnormality in any of these
birds. All birds were feather
perfect except the last two
1999 youngsters to fledge which
presented typical PBFDV symptoms
with primary flight and tail
feather shaft fractures. Birds
tested negative for APV (Avian
Polyoma Virus) and Chlamidia.
Initially only 1998 youngsters
were affected but then sub-adult
and even adult birds became
symptomatic and died.
Frantic pathologist cooperation
finally isolated viral inclusion
bodies in some individuals and
they ran the PBFDV (Psittacine
Beak and Feather Disease Virus)
PCR (Polymerase Chain Reaction)
probe which tested positive.
While this was a relief in terms
of finally discovering a positive
cause of death, the ramifications
were enormous. Where did this
come from? Which were the carriers?
What was I to do?
The specialist avian veterinarian
involved mentioned that in the
many autopsies he had performed
in past years around RSA on
originally wild caught Cape
parrots, it was not often that
he could ascertain an obvious
cause of death. It was usually
presumed that the birds had
died from stress associated
with their capture from the
wild. However he observed that
many had displayed similar symptoms
to mine. During the recent annual
Cape Parrot Census, a bird with
mostly only primary flight and
tail feathers was observed.
This is typical of a PBFDV infected
bird and gave cause for concern.
It has never conclusively been
established why the Cape Parrot
has been declining. There is
the obvious destruction of the
Yellowwood forests and the illegal
trapping for the avicultural
trade and occasional poaching
and shooting by farmers whose
orchards are being raided. However
there have been no obvious signs
of disease.
I decided to test my entire
collection and to my horror
discovered that almost all my
breeding Gapes were positive
for PBFDV. Considering that
it is still believed that adult
birds, if exposed to the virus,
do not develop the disease I
was left wondering how these
birds had become infected, as
this had presumably occurred
while they were young. Many
of these birds had been obtained
as originally wild caught adults.
My thoughts turned once again
to the wild birds and I discussed
this at length with a friend
in the Eastern Cane who has
just had breeding success with
the species. She has now tested
her birds and they are, thankfully,
negative. However, 8 freshly
trapped (wild-caught) birds
were tested last week in East
London in view of my results
and 7/8 tested positive! This
raises many questions while
also answering some. It may
also spell extinction for the
species. What percentage of
the wild population is infected?
Presumably they became infected
from infected escaped exotics
or indigenous parrots. As it
is highly unlikely that PBFDV
is an endemic virus, how long
have the wild population been
infected? Some of my infected
(originally wild caught) birds
were over 1O years old. As most
of them were wild caught as
adults (and it is presumed that
only young birds become diseased
when exposed) then it follows
that they were infected up to
a decade ago? Are there any
resistant individuals? Should
any negative wild birds be trapped
to establish disease free captive
populations? Should the wild
birds be now left to their own
fate? So many questions!
During the course of me testing
my entire collection of parrots,
interesting facts emerged. I
used a cocktail of 3 tests (PBFDV,
APV & CP) available through
Molecular Diagnostic Services
(MDS). No adult birds of any
other species in my collection
were infected with any of the
pathogens except the Gapes.
This included the adult Poicephalus
suahelicus which were also negative.
However, juvenile birds were
infected and one African Grey
handraised with the Capes was
positive as were 3 parent raised
Greater Jardine's and two parent
raised Black-winged Jardine's
although their parents are negative.
One handraised P.suahelicus
was also positive. It would
therefore follow that the Poicephalus
as a group are susceptible to
cross-genus infection.
It has been observed in RSA
collections that the PBFDV is
often species specific i.e.
that the Cockatoo strain doesn't
seem to cross over to Amazons
and the Ringneck strain to Lorys
for example. The fact remains
that this is a devastating and
deadly disease. It is rife in
many private collections. I
can only attribute my relative
containment of the virus to
my stringent hygiene procedures
and routines over the years.
It is truly terrifying waiting
for those blood test results.
I made a decision to euthanaze
all my positive birds. That
was truly heartbreaking. It
is simply too difficult to contain
an airborne (feather dust) virus,
no matter how careful one tries
to be. All my years of hard
work destroyed. Out of 38 Capes
I today have 10 negative individuals
remaining. Looking at the birds
you would never ever guess they
were carriers. They were all
feather perfect. Photographers
from all over the~ World have
captured my birds on film and
never could anyone have imagined
this lurking disaster. I did
spare my best breeding pair
(infected) which were moved
to total isolation within KZN
to see if they could recover
in time. However, the male died
during a recent mild cold front,
with which a healthy bird would
have had no problem dealing.
More evidence that the compromised
immune system even battles to
deal with slight temperature
extremes. Although there is
believed to be vertical transmission
(through the egg) in this virus
perhaps the youngsters or even
the embryo can be vaccinated
with a PBFDV vaccine. There
is much research to be done
still and sadly this is a species
which certainly cannot afford
this type of setback.
I can only urge those fellow
aviculturists who are privileged
to own this species to have
them tested for PBFDV. Those
who may be offered wild caught
birds should avoid introducing
them into private collections
at all costs. I encourage anyone
with Gapes to register them
with the National Studbook held
at the JHB Zoo. Any odd birds
can then more easily be paired
up and utilized in a breeding
programme.
Those breeders that are hybridizing
the Cape with the Grey-headed
Parrot should certainly stop
doing this even if the progeny
are destined as pets, as these
hybrid birds do look similar
to either of the parents and
will eventually end up in potential
breeding situations which will
confuse breeders and alter the
true genetic configuration of
the species.
It is certainly illegal to
have these birds without a permit
in RSA. However, in KwaZulu-Natal
the KZN Nature Conservation
Services have, in view of the
severe plight of this species
and as a result of the PBFDV
results in my collection and
of those discovered very recently
in the wild, urged members of
the public to contact their
local zone officer, in order
to facilitate testing of birds
and pairing up of odd birds
into breeding programs and of
cooperation with the National
Cape Parrot Studbook, without
fear of prosecution. However,
should anyone be found to be
in possession of these birds
without the relevant permits
then leniency will be far from
the action taken.
As far as my Capes go I will
sadly lose 8 years of hard effort
and start at the beginning again.
Thankfully none of my other
species have been infected.
Although it has cost me tens
of thousands of Rands in veterinary
and pathologist fees, it could
have been even worse. I now
know where I stand. Every single
parrot at my facility has been
tested and is negative and never
will another bird enter the
front gate without a clean bill
of health and stringent quarantine.
I will continue to randomly
test breeding birds and every
bird bred and sold will be tested
prior to leaving my premises.
This was a totally horrible
and emotionally exhausting experience
and I could never wish it on
anyone.
The Cape Parrot is now at more
risk than ever before of becoming
extinct. The recent national
annual census conducted by Dr.
Colleen Downs of PMB University,
although affected by bad weather
and a shortage of volunteer
counters in the Eastern Cape,
sighted less than 300 birds.
Way down on the 1998 figure
of 500. In terms of species
survival this is certainly a
pitiful number. Dedicated and
concerted effort, research and
especially funding by aviculturists,
conservationists, environmentalists
and academics is now needed
in order to save this unique
and intelligent bird of ours.
If you are in a position to
help in any way whatsoever (financial
pledges, volunteer work or any
suggestions and information)
please contact the headquarters
of the The World Parrot Trust
Africa at The University of
Natal, Pietermaritzburg, Zoology
Dept. Dr Colleen Downs tel.
033-2605127 or Prof Mike Perrin
te1.033-260551 03/2.
In the mean time I will plough
my efforts into the new breeding
season, hoping for less tragedy,
new successes and above all
- reassurances that the DNA
tests and prognosis were accurate
and that I did not kill my beautiful
birds for nothing.
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