(Kate Gammond has been raising Hyacinthine Macaws in hot and humid Bahrain for the past 10 years. She shares her experiences of breeding this beautiful bird with us)
We have been keeping Hyacinthine Macaws for the past 10 years. Although there were two pairs in the collection here at Al Azizia Garden prior to our arrival in Bahrain, no records were kept and the birds were housed in a different location and setting to the one they are now in.
In 1995 when I came to Bahrain the two pairs already here were housed in separate breeze-block, double door walk-in aviaries measuring 11 x 2,8 width x 3.2 high metres. The roof and front of the aviary is chain link. The floor at the front and back of the aviary is concrete and the centre is loose stone. In the middle stands a dead hardwood tree used as a support for freshly cut branches, such as Eucalyptus. Natural hard wood horizontal perches are at the front and rear. The roof at the front and rear is shaded; there is a sprinkler system and strip lighting protected by wire mesh.
Both pairs were given a choice of upright or horizontal nest boxes, and both seemed to prefer the upright. These boxes measure 48 high x 14 x 14 inches (120 x 35 x 35 cm) and are made of 3/4 inch (20 mm) marine ply. They are reinforced with strips of galvanised sheet. The nest material is wood shavings. The inside of the box is lined with off-cuts of wood for chewing on.
The nest box is located 1.4 metres (4'6") above the floor and is bolted into a 2-inch (5 cm) angle iron frame. They are situated at the rear of the aviary and are not removed, apart from for cleaning and repair, as the birds spend time in the nest box throughout the year.
Their daily seed diet consists of large sunflower seed (washed and soaked), peanuts (washed and boiled due to the possibility of harmful aflotoxins), walnuts, pine nuts and almonds, and also Brazil nuts when available.
The fresh daily diet includes washed, soaked and cooked pulses of green peas, chickpeas, black-eyed beans and yellow corn. They also have the following chopped fruits and vegetables: apple, orange, grape, carrot, local greens and beetroot, when in season.
This forms the bulk of their diet and they are fed in the morning and again in the afternoon. Fresh water is always available. The food is given in stainless steel dishes. Prior to their breeding cycle, powdered calcium is sprinkled onto their food twice a week and water-soluble multi-vitamins are added to the drinking water.
There was no breeding in 1994, due to the birds having been moved to their present location. We also find that the Hyacinths are our last birds each season to breed. The male and female of both pairs start spending more time in the nest box from around the end of March.
They will take out some of the wood shavings and form a hollow in the centre of the nest. More time is spent at the rear of the aviary, there is a lot of mutual preening and calling and the birds become aggressive. They do not tolerate anyone wanting to examine the inside of the nest box and will attack, therefore two people are needed - one to occupy the birds while the second keeper checks the nest box. When mating, the male and female are side-by-side and press cloacae together. Sperm passes from the male into the female.
If not seen mating they are very often heard as they become quite vocal! One to three eggs are laid. It is the female who incubates the egg (s) but she does come out to feed and stretch her wings, usually first thing in the morning and again in the early evening. The male spends time in the nest box with the female throughout the day, though I do not know if he feeds the female.
The decision to either leave or remove the eggs is dependent upon the following factors:
* High humidity
* Is the female sitting on the eggs and not in and out of the nest box?
* Clutch size - how many eggs are in the nest?
* How many are fertile.
If the eggs are removed from the nest and are fertile they are placed in an incubator with a temperature of 37.5°C and a reading of 20-30 on the wet bulb thermometer. This is a moving carpet incubator and it is set to turn 1 x 60 minutes.
The incubation period is given as 28-30 days. The eggs are candled once per day, this is how I monitor the development of the eggs. Once the egg internally pips (penetrates the membrane) it is placed in ahatcher. The temperature is set at 37°C with water added to give high humidity. The chick usually hatches within 24 to 72 hours of the internal pip.
Initially the chick is placed in a plastic carton with tissues for bedding, which are changed after every feed. Not only is this good hygiene but also checking the faeces, the colour and consistency etc. can tell you when the remains of the ingested yolk sac have passed through and if the food is digesting properly.
Pair A has bred, though we do not know the full history prior to 1994 as no records were kept. In 1995 two fertile eggs were laid in. May. Both were removed to the incubator and both failed to fully develop. One fertile egg was laid in June and the egg was left with the birds. On inspecting the nest at the end of the incubation period it was found to be full term DIS (dead in shell). We examined the foetus, it was fully formed and the yolk sac absorbed. There had been no internal pip.
In 1996 the female was removed for treatment - she was not eating and had become very thin. She was given Baytril 5% and multi-vitamin injections twice a day for a week. As this coincided with her breeding cycle, no eggs were laid. The female fully recovered but due to the heat she was kept inside for the remainder of the summer and returned to her mate at the end of September.
In May 1997 she laid one fertile egg and this was removed to the incubator in the hope that (a) we would have a live chick, (b) because of the high humidity, and (c) we hoped that she may lay again. The embryo developed for 18 days and then died. No further clutches were laid.
In 1995 between February and April six eggs were laid, all were infertile. In 1996 the female laid two eggs in April. The humidity was excessively high and the decision was taken to remove the eggs and place them in the incubator. Both eggs were fertile. The female was given a small white chicken egg in place of her own. We hoped to be able to return one egg prior to hatching to be parent reared but she did not sit on the placebo egg.
The first egg was an early embryonic death due, we think, to the membrane not attaching. The second egg was fertile and hatched at 28 days (Chick 1 ). The female laid a second clutch of two eggs in May. Again the eggs were removed to the incubator and again the first egg was an early ernbryonic death. The second egg pipped at 24 days and the chick hatched two days later (Chick 2). This was an assisted hatch and no further clutches were laid.
In April 1997 the female laid two eggs. Both were removed to the incubator. The eggs were fertile and both were early embryonic deaths. A possible cause could be that a new room had just been completed for the incubators. The immersion heater was on the same circuit as the wall sockets, it fused and we lost power to all the wall sockets in the room overnight. So I presume that the temperature fluctuation was at a crucial stage in the development of the eggs.
A second clutch of three eggs was laid in May/June. These were removed to the incubator and the female was given two infertile macaw eggs to sit. She sat on these for 10 days. Two of the three eggs were fertile. The first was full term DIS and the second hatched in July (Chick 3).
The first egg of the third clutch was laid in July and was left with the birds. When the nest was checked later that month there was a second egg. Both eggs were removed and replaced with two white chicken eggs, which she continued to sit. The eggs were fertile but the first egg was a very early embryonic death as there was just a red ring visible when candled.
The second egg fully developed and when the chick broke the shell prior to hatching, it was placed back with the birds. It hatched in the nest but when we checked the nest box the following day there was no food in the crop. It was decided to remove the chick for hand rearing because of the aggressive nature of the birds - we were worried that the chick may be attacked (Chick 4).
Hand rearing formula
This is food I prepare myself and consists of equal quantities of egg rearing food, spring vegetable baby food, peanuts (skinless and unsalted) and muesli (no added sugar or salt). The dry food is blended together until the texture is quite fine. When fed to the chicks it is mixed with boiled bottled water. The tap water in Bahrain is desalinated - very few people drink it unless it has been previously boiled. The wet mixture resembles a thick soup depending on the age of the chicks.
When the chick hatches the shell is removed and if necessary, anti-biotic powder is applied to the umbilical area. It is weighed and given warmed lactated ringers solution and placed in a clean container with fresh tissues. The chick will be given a drink of this every hour for the first day. I use lactated ringers because it gives essential electrolytes and I think this helps to aid digestion when food is given.
The second day the chick is fed a weak solution of food every 90 minutes. The third and fourth days the food is thicker in consistency and the chick is fed every two hours. At the end of one week the chick will be on normal consistency and will be fed every three hours.
As the chick grows the crop holds more food and the feeding becomes less frequent, settling on four feeds per day until they start to wean. My chicks are not fed 'x' grams of food per feed or day, they are fed enough food to comfortably fill the crop. I spoon-feed all chicks I hand rear and this is nothing other than a personal preference.
The temperature in the brooder is important for the digestion of the food. If the temperature is on the cool side the chick becomes lethargic, therefore the crop is slow to empty. If the chick is too hot I have noticed that it becomes restless and agitated and will shout and 'throw' itself about. A healthy, 'happy' chick is pink, warm when touched, shouts for food but soon settles once it has been fed.
As the temperature in my 'baby room' is around 27.5°C the chicks only remain in a brooder for 5-7 weeks. They are then placed in a large plastic box which has a wire mesh tray to give the feet something to grip onto, and to allow any faeces to pass through. They are placed in a cage only when they start to climb, though this usually coincides with the weaning stage of their development.
All four chicks were offered cooked pulses, peas, black-eyed beans, yellow corn plus small pieces of carrot, apple, banana and fresh corn-on-the-cob when they were around eight weeks of age.
By this age they are awake more of the time between feeds and are inquisitive, they shout when you enter the room. They also show fear, flipping over onto their back in a submissive position if someone strange enters the room or there are noises that they are not accustomed to. I have found this to be temporary - as they grow and gain more confidence and independence, anything or anyone new is greeted with a loud shout.
They soon start sampling food, with banana being a firm favourite. They are still given four feeds per day as feeding stimulates the appetite, though the amount given is less because, like a baby, they will not swallow the food they do not want. Sunflower seeds and peanuts are introduced into their diet, as are walnuts, but these are broken for the birds as their beaks are not yet strong enough to break the shell.
As they become independent the number of feeds are reduced to 3 per day, then down to 2 feeds, morning and evening, and then one morning feed.
Finally when offered food they show little interest or will not swallow it. The chick is no longer fed, but it will remain in the weaning room until I am satisfied that the amount the bird is eating daily is enough.
Chick No. 2 was fully weaned at 4 months, but chick No. 1 took 7 months. This was not because he wasn't eating any seeds or fruits - they are sometimes reluctant to give up the rearing food, even if it is just two spoonfuls per day plus the attention they receive! Perseverance is rewarded when they are fully independent and eating a varied diet.
Ringing and sexing
All the birds have a closed band steel leg ring size 14 mm; this is placed on the leg of the chick at approximately four weeks of age. We DNA sex the birds by taking a blood sample from a clipped nail which is sent off to a UK company. All four birds have been sexed as male.
The following table shows the weights of the chicks at various stages. There was a difference of six grams in the hatch weight of the smallest chicks. All reached peak weight between 11 and 14 weeks of age. The birds will reach adult weight (1000-1400 grams) at around two years of age.
Hatch weight Peak weight Weight when weaned
Chick No. 1. 21.5.96 28 g Age 12 weeks 1,472 g Age 7 months 1,199 g
Chiek No. 2 15.6.96 22 g Age 12 weeks 1,334 g Age 22 weeks 1,107 g
Chick No. 3 7.7.97 26 g Age 11 weeks 1,394 g Age 20 weeks 1,176 g
Chick No. 4 11.8.97 22 g Age 14 weeks 1,449 g Age 6 months 1,150 g
(Ed: Click here for chart)
Later breeding patterns
Pair A laid two clutches of eggs in 1998. The first clutch was left with the birds to incubate; there was an internal pip but the chick failed to hatch. We opened up the egg and there was a lot of yolk sac present but the humidity had been high.
The second clutch of two eggs was laid in July, and both were fertile. The eggs were removed to the incubator and the female was given two infertile macaw eggs to sit. The first egg hatched independently at 27 days and weighed 24 g. When the second egg externally pipped we decided to place it back in the nest. We felt that we had been a little hasty in our decision to remove the chick from pair B. We checked the nest after two days - the chick had not been fed and it had died.
Pair B laid two clutches of two eggs, all of which were fertile. The eggs were removed to the incubator due to the excessive heat and humidity. All hatched independently. The eldest two chicks have been DNA sexed as a male and a female.
All of the chicks were successfully reared and weaned. Of the five, the female chick of pair A has been paired with Chick 2 from pair B. This pair laid their first clutch of one egg in June 2003.
The egg was left with the female and she seemed to cope well with incubation. At 26 days we removed the egg for candling but it was not fertile. Two fertile eggs were laid towards the end of July. Again they were left with the female, and both eggs were early embryonic deaths. It is not unknown for captive-bred
females to breed at this age; she was just under five years old when the first egg was laid.
The Hyacinthines have been one of our most prolific (and fertile) egg layers compared to some of our other larger macaws, such as Scarlets and Blue and Golds. The breeding of these birds has not been a problem. I do not find the chicks any different or more difficult to rear than other large macaw chicks.
We are still using the same rearing formula and I still prefer to spoon-feed our chicks.
Cause and effect?
When you read published articles or talk to other aviculturists there is one fact that keeps emerging: a lot of fertile eggs fail to fully develop or you have D.I.S prior to hatch. This is regardless of the eggs being left with the parents to incubate or taking the eggs for artificial incubation.
I think the early embryonic deaths, i.e eggs that have only developed for a few days, can be explained. The membrane needs to attach and remain attached for successful development and the egg needs due care and attention. As the pair of birds will be in the nest together it is feasible that the eggs are disturbed too much at this crucial stage in the development.
Looking back at our records we find that eggs that have internally pipped and gone more than 24 hours without an external pip result in D.I.S. Bearing in mind that it is not unusual for an egg once it has made the internal pip to take up to 72 hours to complete the hatch, does weather play a factor in the issue? The breeding season for our Hyacinthine macaws coincides with the temperature and humidity in Bahrain rising. At the height of the summer it is in the high forties, giving apparent temperatures of 50 C+. This can start at the end of March and last until September.
We have come to the conclusion that if the weather is hot (40 C+) and the humidity is high during the first half of the (parental) incubation of the egg, the egg is likely to be a mid-term embryonic death. If the weather is hot and humid during the second half of incubation the chick is likely to internally pip at 23 days into the incubation and hatch at 24-25 days.
The other factor is that all our full term D.I.S have not made that external pip. If the chick has enough oxygen in the air sac once it has made the internal pip to allow for 24-72 hours to complete the hatch, why is there no external pip? On examining the failures we find that the shell is hard, possibly too hard even for the egg tooth to break through. This has been noted by other breeders and commented on.
Therefore do eggs that are left in the nest, having made an internal pip but failing to hatch, give us reason to believe that the parent bird takes no part in assisting the hatch? The chick will be shouting and as time progresses, getting weaker. Does the female not recognise a cry for help because she does not know what to do, or is it a case of if the chick is not strong enough to hatch it will not make a strong adult?
If by removing the egg from the nest and assisting with the hatch, either returning the chick to the parents for rearing as some aviculturists do, or hand rearing, surely this would guarantee the survival of this species in aviculture. It would give a larger diverse gene pool and help preserve the wild population.
This information is based on 10 years of record keeping and, as such, applies to keeping these birds in Bahrain. As with most countries, these last few years we have had anything but the expected seasonal weather and with this change we have noticed variations in the cycles of most of our breeding birds. It is a factor that has to be taken into consideration on what now seems to be a yearly basis. Do other aviculturists take into account climatic conditions in their locations and by doing so, would they see a change in their hatch rates? Considering the changes in the weather, will our information result in a higher hatch ratio in the future?
We now regularly give pro-biotic to all of our birds. We have lost birds due to gastro intestinal problems; this usually occurs when the temperature changes i.e. cool to hot and vice-versa. Also when the humidity is high, bacteria can develop rapidly on the fresh food; Bahrain always has a seasonal outbreak of 'tummy upsets' so there is also the possibility of zoo noses. Therefore giving probiotic helps to maintain a healthy gut flora.
The birds now use horizontal nest boxes; they were again given a choice. If the egg is 23 days into incubation and has internally pipped I don't now think, "this is too early". I will make a small hole in the air space of the egg, as I did with all four that successfully hatched this year. If the full term chick is dying due to lack of oxygen because it hasn't been able to make that external pip, this gives it a fighting chance. The egg can continue to hatch unassisted or if there are difficulties then you can assist the chick to hatch.
Kate Gammon has sent an up-date to 2004, which can be accessed by clicking here
Thursday 7th November 2019
Loro Parque Foundation has reintroduced six Lear’s into the wild in Brazil
I read a report on the blog page of the Loro Parque Foundation published in February 2018 that they sent six Lears bred in Loro Parque in Tenerife to Brazil in August 2017 to be reintroduced into the wild there. They have managed to adapt to ... Read More »
" Naturam expellas furca, tamen usque recurret "
( If you drive out nature with a pitchfork, she will soon find a way back)
Horace (65-8 BC)