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Vol 28 Issue 12 • Dec-Jan 2016
SENEGAL PARROT
PET BIRD CARE
Moluccan
Cockatoo
RED-RUMPED PARROTS Nectivores Status of
AUSTRALIAN FINCHES Pigeon Racing
Vol 28 Issue 12 • Dec-Jan 2016
SENEGAL PARROT
PET BIRD CARE
Moluccan
Cockatoo
RED-RUMPED PARROTS
COVER IMAGE MOLUCCAN COCKATOO BY PETER ODEKERKEN
Nectivores Status of
AUSTRALIAN FINCHES Pigeon Racing
contents Volume 28 Issue 12
features 753 PEACH-FRONTED CONURES
772 MY FIRST MACAW
790 A PIECE OF PARADISE
By Armin Brockner Its petite size, quiet disposition and endearing appearance make the Peach-fronted Conure a favourite among bird keepers.
By Dorothy Schwarz Dorothy relates her experiences in raising her first macaw—weaning and feeding, socialisation, training and freeflight training.
By Hanne Van Bavel, Andreas Frei, Jan Dams and Antje Mewes
764 KEEPING AND BREEDING THE SENEGAL PARROT
782 THE MOLUCCAN COCKATOO
By Jade Welch and Mark Mills The Senegal is a highly intelligent species, small on size and big on personality.
By Peter Odekerken This stunning, endangered native of Indonesia requires enrichment in captivity.
Birds of Paradise have a unique new home in Weltvogelpark, North Germany. 798 AN INTRODUCTION TO PIGEON RACING
By Tas Gazis Passion and devotion go a long way toward winning a big pigeon race.
regulars 756 BREEDING AUSTRALIAN PARROTS: RED-RUMPED PARROTS
non-aggressive species is a favourite grassfinch in the author’s aviaries.
By Barry Blanch The Red-rump’s quiet nature and soft call makes it an excellent beginners’ parrot and perfect for backyard aviaries.
778 ABOUT BIRDS: THE SWEET LIFE OF NECTIVORES
760 FINCH FOCUS: THE STATUS OF AUSTRALIAN FINCHES
By Kit Prendergast Kit uncovers the pros and cons of nectivory and how different species have evolved for life based on a diet of nectar.
By Russell Kingston Russell examines the status of Australian finch species, both in the wild and in captivity.
786 BUILDING BLOCKS FOR BETTER BIRDS: BUILDING A BETTER RELATIONSHIP WITH A HANDS-OFF PARROT
767 BUSH TUCKER: FOODS FROM THE ASTERACEAE FAMILY
By Des Boorman This is one of the largest plant families, with around 25,000 herbaceous and annual plant, tree and shrub species. 769 ASK THE EXPERT: COLLECTING COCOS PALM FRUIT
By Des Boorman 770 HOOKBILL HOBBYIST: FLEDGING STUDIES—PART 3
By EB Cravens Breeders can control fledging, making it a safe, enjoyable and exciting experience for the chick, and helping to develop a healthy adult, both mentally and physically. 775 FINCH FUNDAMENTALS: THE MASKED FINCH
By Marcus Pollard Often overlooked, this inoffensive,
By Rebecca K O’Connor Some parrots find handling to be a highly aversive situation. You can still gain your parrot’s trust and engage in building a relationship by patiently creating positive experiences with your bird through ‘hands-off’ training activities. 788 THE WISE OWL: A FEATHER’S TOUCH
By Milton Lewis You will never look at the humble House Sparrow the same way again after reading Milton’s research into the sparrows of Dassen Island.
795 CANARY CHATTER: BREEDING CANARIES IN AUSTRALIA—PART 3
By Brian Bohl Brian looks at the considerations involved in establishing outside aviaries and indoor birdrooms. 800 CONSERVATION:
• LPF: Tree-nesting Military Macaws By Dr David Waugh • WPT: Protecting Amazon Parrots By Carolyn Pradun 804 WHAT’S NEW:
• Why Does My Parrot...? By Rosemary Low • Birdscaping Australian Gardens By George Adams • Backyard Bird Sounds By Fred van Gessel 805 WILD CORNER: WELCOME SWALLOWS IN A STICKY SITUATION
By Dr Claude Lacasse 806 LAST CHIRP:
• Annual Zebra Finch Team Show By Ken Glasson • Hunter Valley Finch Club Bird Sale By Marcus Pollard
792 AVIAN HEALTH WITH DR BOB: LOOKING AFTER YOUR PET BIRD
By Dr Bob Doneley Dr Bob offers advice on the basic considerations when selecting, housing, feeding and catering for a healthy future for your pet bird.
808 classifieds 751
WORDS AND PHOTOGRAPHS BY ARMIN BROCKNER
KEEPING AND BREEDING
Peach-fronted
Conures INTRODUCTION
South America is home to a vast variety of different species of parrots, many of which have become established in captivity. The macaws, renowned for their speaking prowess, are a key example. However, smaller South American parrots such as parrotlets in the genus Forpus, and conures such as the Pyrrhura have also captured the hearts of bird-lovers. One of these smaller, popular South American species is the Peachfronted Conure Eupsittula aurea (previously Aratinga aurea), also known as the Golden-crowned Conure. Its petite size, measuring 25cm in length and weighing 80–105g, quiet disposition and endearing appearance make the Peach-fronted Conure a favourite among bird keepers. It is also suitable for newcomers to keeping parrots, readily establishing a trust with people as well as breeding easily. It is one of my favourite birds, and each day I enjoy standing in front of the aviary of Peach-fronted Conures.
Peach-fronted Conure Eupsittula aurea
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finch focus
ON AUSTRALIAN FINCHES O WORDS AND PHOTOGRAPHS BY RUSSELL KINGSTON OAM
THE STATUS OF AUSTRALIAN FINCHES INTRODUCTION Question: Which Australian finch species are at risk in the wild? Answer: They all are. It is only the immediacy and seriousness of the risk that varies from species to species. Australian finches in captivity fare little better, albeit for different reasons. So, what are the threats and what is the likely prognosis for these birds? In this article I examine the issues relating to each species, both in the wild and in captivity. Naturally, in most instances, there are common issues running throughout the various species. However, there are also unique threats to some.
AUSTRALIAN FINCHES The true finches are passerines from the family Fringillidae, whereas other Passeriformes belonging to the Estrildidae family are also referred to as Estrildid Finches. All 18 indigenous Australian finches belong to the Estrildidae family. There are no naturally occurring Fringillidae finches in Australia, although European Goldfinches Carduelis cardeulis (subspecies C. c. britannica) and European Greenfinches Chloris chloris have been introduced into south-eastern Australia and become well established. These introduced species have created two problems for Australian finches sharing the same regions of distribution. The first problem is that of displacement and is not regarded as a serious threat. While there is anecdotal evidence to suggest some competition for food and breeding space, in general terms, goldfinches and greenfinches are not considered a serious threat to native populations of Australian finches. The other threat, however, is more serious. Research carried out by Associate Professor Lucio Filippich in the 1980s and 1990s revealed that up to 90% of the wild Goldfinch population in Australia carried megabacteria (avian gastric yeast). This has found its way into wild populations of Australian birds, including parrots, and subsequently into captive populations. The other successful introduction into Australia is the Spice Finch Lonchura punctulata, a munia from South-east Asia. This species has established in northeastern Australia. It has established itself in regions occupied by the Chestnut-breasted Munia Lonchura castaneothorax. The two species associate, forming combined flocks. While the two species share common feeding and breeding, there is no evidence to suggest that the wild population of Chestnut-breasted Munias has been adversely affected by the association. I have never seen any evidence of crossbreeding between the species in the wild, although their close relationship suggests there is every possibility of this happening. Goldfinches and greenfinches cross-breeding with Australian Estrildids is very unlikely.
THE THREATS In the Wild The two most common issues facing Australian finches in the wild are climate change and human expansion. Climate change is frequently misinterpreted as global warming. Certainly warming is part of climate change, but so too are more severe storms, increased rainfall (La Nina), cold in
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some regions and prolonged drought (El Nino). Heat and drought are the two most destructive factors as far as Australian finches are concerned. Already, there are recordings of large-scale losses of birdlife in Australia and this is predicted to increase as global climate change intensifies. Human expansion not only involves housing and industrial development, causing loss of habitat and decline in air quality, but also agriculture and mining practices that result in toxic sprays, land degradation, introduced pests and flora, and water pollution. Human expansion is a serious threat to all Australian finches. All of the above issues result in less natural habitat, food sources and water. Stress from these problems can result in increased incidences of disease.
The monochromic colours in some species, such as the Yellow-rumped Munia, have little appeal for some breeders
In Captivity Australian finches in captivity face different and potentially more severe problems. These include inbreeding, proliferation of colour mutations, disease, declining interest in keeping indigenous species, lack of fresh genetics, and lack of breeding expertise. Let’s look at these in more detail.
Inbreeding and Cross-breeding Inbreeding between subspecies is becoming more prevalent in this country. This was something common in Australian species kept by European breeders—the reason being a shortage of normal birds. I cannot provide a reason for breeders resorting to these practices here other than perhaps, for the same reason. For instance, the inability to procure a mate for a Whitebellied Crimson Finch may encourage the breeder to mate a Black-bellied form with his White-bellied bird. The result is a grey belly or irregular white markings on the belly. Long-tailed Finches have been cross-bred with Black-throated Finches so as to expand colour mutations into one or the other species. In these instances genetic impurities are compounded with impure colours and hybridisation. Recently, more hybrids are appearing between Black-throated Finch species Poephila cincta and P. c. atropygialis. I am unable to offer an explanation for this, as both species are available to aviculturists.
Keeping and Breeding the Senegal Parrot WORDS AND PHOTOGRAPHS BY JADE WELCH & MARK MILLS
Senegal Parrot adult male
A
member of the Poicephalus genus, the Senegal Parrot is a predominately green bird with a big personality. Although no longer sold here at Perky Parrots on the Gold Coast—as we move away from keeping the smaller species—its popularity is such that a reflection on our time keeping and breeding Senegals appeared worthwhile. The Senegal Parrot is truly a great bird and this article may assist those wanting to venture into keeping this highly intelligent species with a quiet deameanor.
ACQUISITION
Senegal Parrot adult female
As with any acquisition of new stock, one of the most important tasks is to ensure that quality birds are sourced. Ours were obtained from a National Exotic Bird Registration Scheme (NEBRS) registered breeder six years ago. From there the birds were vet-checked and placed into quarantine. Once quarantine was complete, each pair was moved to their own aviary. Having heard that Senegal Parrots are nervous birds that like their privacy, they were put in a quiet spot. Here, although they could not see one another, they could certainly hear one another. They quietened down quickly and would even come down to inspect the bowl of food as it was being placed in the aviary.
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hookbill hobbyist WORDS AND PHOTOGRAPHS BY EB CRAVENS W
FLEDGING STUDIES—Part 3 F OFFERING DESTINATION SITES A good proportion of the fledging urge in psittacine chicks is their strong wish to get away from where they are, rather than having a specific destination to target. We therefore place a second towel-draped nursery basket right next to the one that has been the babies’ home for weeks. Elder siblings will choose to climb out and away from clutch-mates to be by themselves in these second baskets, placed about 15–20cm away from the first holding basket. These new baskets have diversions within, like green branch sprigs, cut clean flowers, millet spray and a safe soft plastic toy or two for the birds to sample. That is the first step in controlling the entire fledging process—giving chicks a goal rather than just letting them go wherever they end up. Sometimes, when there are many offspring, we set up three large towel-covered baskets in close proximity. You will know precisely which siblings are on the verge of fledging because they will all have climbed together into the new basket—often flapping madly after a meal! A quiet atmosphere for chicks, together with the new destination site, normally delays fledging about 4–7 days, depending on the species and its level of confidence. If you wish to prolong the tentative period prior to first flight, move all the holding baskets to another serene location, entirely different from the first. In our case this would mean putting the babies in their baskets on the bed in the master bedroom. Older birds which have been visually checking out the surroundings in the original room in preparation for first flight attempts will now need several days to survey and accustom themselves to the new positioning before deciding to take off. Make sure the new spot is free from stressful noise and activity so the chicks do not regress into shyness. When chick fledging becomes imminent, we begin systematically setting up the control environment for safe flight. This is done using two or three covered baskets placed 30–45cm apart, and a sturdy branch or two. The babies recognise instantly the handles and sides of another basket and will begin the process of ‘hop and flap’—that is a short jump-flight from one secure site to another. As activity of this sort increases and food dishes and green foliage are added, we start to move the landing sites further apart—1m, 2m, across the room, and the like. Almost every hookbill youth will choose to fly the longer distance to a familiar basket. One may also be placed in front of the sill of any windows in the room, effectively shutting off the danger of a chick crashing into the glass, instead landing on a basket in front of the window. The keeper will easily be able to see when fledglings are becoming more skilled at flight as the advanced fliers will begin to pick up speed, much like a teenage driver. They will often fly across the room, turn around in mid-air above the intended landing basket, branch or rope perch, and instead circle back to land whence they began! When a hand-feeder takes these logical steps to monitor and influence the fledging process, it is pleasing to see the way chicks begin to conform to predictable first-flight patterns and no longer just take off and crash about randomly. This is advanced aviculture and is well worth any extra effort it entails.
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Provide subdued lighting and a safe place to retreat and allow chicks to venture out and fledge at their own pace
MENTAL ALERTNESS AND FLIGHT Years ago, when it was popular practice in the USA to trim the wings of fledgling baby psittacines before or soon after they began surging from their nursery enclosure and crashing around the room, little was written about what such methods did to the mental conditioning of the birds. Flying is one of the natural skills that baby parrots do best and it is critical to their development as healthy, well-adjusted pet hookbills. Most baby psittacines are raised in near-total darkness. They are warmed and tended to by their mother, sometimes their father, for weeks on end with little visual stimulation. Touch is what the nest box experience is all about. As wing and tail feathers begin to grow in length, neonate parrots get more active. They commence early, uncoordinated stretches of one wing, then the other, teetering on one foot in the darkness. They start soft, muffled little flappings of bloodfeather-encrusted baby wings that are incapable of producing breeze, let alone any real lift. The chicks’ instincts cry out for muscular exercise where it most counts, in the breast and wingspan. Increase in calorie burn-off results in the chicks having a greater capacity to eat, while baby fat begins to evolve into more dense and wiry muscle. The babies’ now wide-open eyes begin to distinguish the lighted nest opening where its parents enter to administer warm regurgitations, closeness, preening and touch. As their baby feathers grow, and flapping exercise becomes more exuberant, their tiny parrot minds start to grapple with a single overwhelming concept—‘That is the way out’. The eldest, or strongest, or most courageous of the offspring—frightful as it seems—learns to climb that ladder towards the brightly illuminated exit. ‘It’s hot and crowded here, and there is not enough room to stretch my wings,’ its mind exhorts, wondering at the same time what its parents do outside. Up at the entrance, peering into brilliant afternoon daylight, the chick appears shy and hesitant. Its eyes widen in
K LIGHTBODY
K LIGHTBODY
Two Western Australian species, the Western Wattlebird Anthochaera lunulata and Red Wattlebird Anthochaera carunculata contesting to feed on the same Banksia bloom
Brown Honeyeater Lichmera indistincta feeding on Kangaroo Paw at Wireless Hill south of Perth—note the pollen being deposited on the back of the bird's neck
A DIET OF NECTAR
oesophagus, lying below the crop, which produce mucous to help hard foodstuffs glide through the glandular stomach (proventriculus) and prevent hard items causing damage to the gut.
Nectar is a dilute solution produced by plants to attract pollinators. Sugars comprise almost 100% of its dry weight. Nectar provides large volumes of easily digestible energy for birds evolved to harvest it. Nectar has advantages over other foods, like insects, that must be captured and often possess tough chitinous exoskeletons and defensive structures or chemicals, or seeds enclosed in tough casings. However, nectar contains very low levels of amino acids (a nitrogen source required for protein synthesis) and is also poor in vitamins and trace minerals required for a bird’s maintenance, growth and reproduction. Nectivores require very little nitrogen. For example, both honeyeaters and hummingbirds have protein requirements of only ~1.5%, compared with ~8% for granivorous birds. However, amino acids are still necessary. Minimal levels in nectar (<2%) mean most nectivores supplement their diet with alternative nitrogen sources. Pollen is a plant’s male gametes, brushed off onto pollinators to achieve cross-pollination as they feed between flowers, but can also be used as food. Pollen protoplasm (pollen grain content) contains highly digestible protein with copious amounts of diverse amino acids, and can be harvested with nectar. Active pollen harvesting has been observed especially in Rainbow Lorikeets, Purple-crowned Lorikeets Glossopsitta porphyrocephala and Swift Parrots. Unlike lorikeets, a honeyeater’s digestive tract cannot extract the contents of pollen grains, hence they obtain negligible nourishment from pollen (any pollen ingestion likely occurs incidentally). Insects are the main protein source for most nectivores (especially large honeyeaters). Insects are predated mainly during bird reproduction, especially to meet growing chicks’ higher protein requirements. However, many insects cannot be digested by many nectivores which lack gizzards capable of shattering insects’ tough exoskeletons.
Nectivore Gut Structure
Mechanical digestion of food occurs in the gizzard. Corresponding to their liquid diet, the gizzard of nectivores is comparatively smaller and less muscular, and in Glossopsitta lorikeets, the gizzard is barely recognisable. Longer guts increase the retention time of food so that hard-to-digest food can be broken down. With their highly digestible diet, nectivores are characterised by short intestines. With a soft, liquid diet, nectivores have reduced the glands within the
A High-sugar Diet Nectivores are major sweet-tooths (or sweet beaks)! Consuming prodigious amounts of sugar corresponds to high glucose levels that would be deemed severely hyperglycaemic for humans. In hummingbirds, fasted blood glucose is 300mg/ dl, increasing to 740mg/dl following feeding. Not only do specialised nectivorous birds thrive on this high-sugar diet, they recover most of the glucose filtered by the kidneys rather than losing it in urine. Hence, despite being naturally hyperglycaemic, they do not become diabetic and are free from developing polyuria (glycosuria), polydipsia and polyphagia most animals suffer when ingesting excessive sugar. Specialised nectivores have guts physiologically adapted to process high sucrose levels. They have high levels of sucrase (the enzyme responsible for hydrolysing sucrose) in their intestines, resulting in almost 100% digestion efficiency. In contrast, specialised insectivorous birds (namely species in the superfamily Muscicapoidea, eg thrushes), lack sucrose and hence are sucrose-intolerant. If they are fed sucrose, it accumulates undigested in the gut, leading to osmotic diarrhoea.
A Dilute Diet For most land animals, the major challenge is to prevent desiccation and dehydration, and to conserve water. Nectar’s high water content, low protein content, yet relatively high sugar concentration means nectivores are at the other end of the spectrum in regulating water and solutes. Because nectar is relatively dilute, wild hummingbirds do not drink free-standing water, obtaining enough water solely from their diet. However, for other nectivores, additional water is vital. Because nectar is more concentrated than blood, when passing through the gut, the concentration gradient causes water to be drawn out of the blood into the gut and lost in the urine. To prevent dehydration, most nectivores must drink fresh water regularly. The hummingbird’s ability to avoid osmotic dehydration is a result of their intestinal membranes being impermeable to glucose. Instead, special proteins regulate glucose uptake from the gut, without water being lost into the gut in the process.
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T
he Moluccan or Salmon-crested Cockatoo Cacatua moluccensis is a stunning, large bird—one of the largest of the white cockatoos. Sadly, it is under threat because of the live bird trade and habitat destruction. However, as Westerners we must understand that exploiting wildlife is for many a way of sustaining a family’s livelihood. We can help this species and others in the same predicament by supporting ecotourism. The income obtained from birdwatchers could make local people adopt a policy of not harming or even result in them nurturing their wildlife.
IN THE WILD Distribution The Moluccan Cockatoo’s last stronghold is the large island of Ceram, Indonesia. Many would certainly challenge the word stronghold as it has been exploited so heavily that genetically it may prove difficult to not affect the gene pool. However, Ceram is a very large island and trafficking in this species has dropped—at least it is less likely to be seen in open ‘burung’ bird markets. Undercover, it seems virtually any species can be obtained in Indonesia. The Moluccan could previously be found on the islands of Ambon, Saparua and Haruku, but has apparently disappeared and if seen is usually an escapee.
Habitat and Habits This is a lowland forest species restricted to an elevation of about 1200m and can still be found on Ceram in forest with large trees for nesting. The population density is muchreduced and some Indonesians are concerned for the species’ future. Surprisingly, Moluccan Cockatoos can be found quite close to settlements where the forest has not been totally disturbed. They are shy birds and fly off when humans appear or are heard. If you travel in Indonesia as I have done, you will know it is much more difficult to get close to wildlife than it is in Australia. Cockatoos in particular will raise the alarm and often disappear before we can get a decent view of them. As in most species, Moluccans are more active early or late in the day, with the humid and very hot mid-morning to afternoon being spent in the shade. They feed on a variety of nuts, seeds, berries and even young coconuts. Insect larvae is also sought-after and no doubt young leaves of certain trees—as most forest species eat tender shoots. Breeding usually takes place mid-year but no doubt pairs can be active at other times depending on the availability of their food source. Pairs can be seen displaying high up, usually in dead limbs above the forest canopy, raising their crests and calling excitedly. They often break off branches and drop them to the ground, particularly when they are aware of human presence. They nest in tree cavities and lay two white eggs on the decayed wood bed. Incubation lasts about 28 days and both parents incubate. Males generally incubate during the day. More than likely, successful pairs will breed once every two years, as the young in large cockatoo species take time to mature and learn the ways of the wild from their parents.
IN CAPTIVITY Housing The Moluccan Cockatoo is easy to sex, with males having a black or dark brown iris and females a reddish iris. Males also tend to be slightly larger in body and beak size. They measure approximately 50cm in length. They need a large aviary in which to exercise and obviously need quality strong wire and a metal frame as the structure— usually 25mm square galvanised tube. Wood will be chewed and eventually need replacement. It is vital to provide wooden perches as metal ones will not give these birds the necessary opportunity to chew. If you dislike replacing perches, don’t keep cockatoos, but don’t resort to metal perches as they are cold in winter and don’t give birds the right gripping
Moluccan Cockatoos are strong birds that require a metal aviary and furnishings
experience, as wooden perches do. It is also important to ensure the diameter of the perch is a suitable size that allows the bird to exercise its feet, rather than providing a thicker perch just because it will last longer. Mating on thicker perches may also become an issue, with the female unable to keep stable while the male mates with her. Alternatively, the male may find it difficult to hold onto the female because he has not been able to exercise the gripping action in his feet. Providing perches of various diameters is recommended. Fresh branches with young shoots, flowers or leaves are welcomed and enjoyed by these birds. They may be torn apart but the birds derive benefit from this habit and nutrition is no doubt taken in. However, always ensure the vegetation provided is non-toxic. We are lucky in Australia as we have a ready source of Eucalyptus and Callistemon species for just that purpose. The aviary should be at least 5m in length x 1.8m wide x 2.1m high, with a covered area which is one-third of these dimensions in Colorbond™ sheeting and roof. Be aware that in summer this can be a very hot area and this will affect your birds and breeding capability. Find a way to cool the aviary down—be it nearby shaded trees, sprinklers or creating air flow out of the aviary which takes hot air away from the birds. I have heard people say, ‘but the birds come from a hot environment, they can stand it’, but they have not noticed that in nature the birds select shade to sit in and there is often a cooling breeze where they perch during the heat of the day.
DIET
These birds should be fed on a quality seed diet of striped sunflower, safflower, oats, white millet and canary seed, with a liberal amount of nuts such as almond, pecan, hazelnut and human-grade peanuts (ensure there is no mould). If you buy large bags from a farmer that has stored the nuts incorrectly, you risk the bird’s welfare. I buy small bags from a supermarket and even then keep an eye open for mould and store them in a freezer until needed. A good quality pellet can also be provided to deliver a wide level of nutrition and particularly mineral content. Calcium can be difficult to make your cockatoos consume so, if they enjoy pellets, this is a great way of providing sufficient calcium to sustain good health and egg production. Another way is to provide a calcium supplement in the drinking water
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