WHERE THE REGENTS ROAM V18 NOVEMBER 20092009 WelcomeWelcome to thethe next eeditiondition ooff WWherehere TThehe Regents Roam, thethe newsletternewsletter forfor thethe recoveryrecovery program offh the Regent R HHoneyeater. CAPTIVE MANAGEMENT Have you ever wondered what it’s like to run a captive breeding program for an endangered species? If so, read on for a fi rst hand account of the program to breed Regent Honeyeaters at Taronga Zoo from the perspective of Michael Shiels, Supervisor of Taronga’s Bird Unit and member of the Regent Honeyeater Recovery Team: Captive breeding an management of Regent Honeyeaters is one of many steps being implemented by the recovery team to address the declines of this charismatic bird. The objectives of the captive management component are to maintain the captive population of Regent Honeyeaters at a size which will provide adequate stock to: provide insurance against the demise of the wild population; continuously improve captive-breeding and husbandry techniques; and provide adequate stock for trials of release strategies. This is all conducted while maintaining 90% of the wild heterozygosity (genetic diversity) in the captive population. During 1995 a team of community bird groups, observers and Taronga Staff, coordinated by the National Recovery Team Coordinator collaborated to collect wild Regent Honeyeater nestlings and their nests from Chiltern State Park (now Chiltern-Mt Pilot National Park) in Victoria. The age at which the nestlings were collected (4-6 days) ensured that the nestlings had a few days of being reared by their parents before being acclimatised to an artifi cial diet. This strategy was used to minimise the risk associated with collection, and to give the chicks a chance to be exposed to natural gut fl ora from their parents. The collection of nestlings rather than adults also reduces the effect of removing breeding adults from the population. Following this three fi rst year Regent Honeyeaters were mist-netted in 1996 in the Capertee Valley at dusk as they returned to their roosting site. These birds were introduced to Wombaroo nectar mix the night they were caught, and then transported to Taronga Zoo. After a lengthy quarantine period in Birds Australia’s Woodland Bird noegal cages and holding aviaries the birds were released into the main aviaries. Conservation project, which adminis- ters the Regent Honeyeater recovery The wild-caught individuals were a bit ‘fl ighty’ when keepers were fi rst entering aviaries compared program, is funded by the Australian to the captive-bred birds, however quickly adjusted well to captivity to judge the boundaries Government’s Caring for our Country. of the aviary extremely well limiting any potential injuries resulting from collisions with the wire mesh. The four off-exhibit aviaries for the Regent Honeyeaters were based on the same FOR MORE INFORMATION ON type of housing used for the Helmeted Honeyeater at Healesville Sanctuary, THE SPECIES, PLEASE CONTACT: Victoria. The aviaries have proven to be very suitable. They measure 6m x 4m x 4m and are constructed with 1.6 gauge painted mesh and “Poly- Dean Ingwersen tuff” corrugated roofi ng. Removable internal petitions between each Regent Honeyeater Recovery Coordinator aviary at the back allow the facility to be confi gured from one to four If you see a Regent Suite 2-05, 60 Leicester St aviaries. Carlton, VIC, 3053 Honeyeater we would P: 1300 621 056 The daily ration for a pair of birds, presented in small stainless steel like to know about it as E: [email protected] dishes, is: soon as possible – please • 6 gm Insectivore Mix (specially prepared diet made by TCSA keepers). free call 1800 621 056 This mix consists of Wombaroo Insectivore powder, whole hard-boiled egg, and fl y pupae. The ingredients are briefl y blended together and water added to give a moist consistency. • 2 small pieces of soft fruit (papaya is the preferred fruit item) • Mealworms fed ad lib. in the afternoon • Water (always provided) • Insects (caught in the moth trap) are provided when available • 70mls Wombaroo Honeyeater and Lorikeet Mix (fed twice daily during summer months) In order to maintain the characteristic yellow plumage of Regent Honeyeaters in captivity the birds are also fed Necton Gelb. This is a purpose-made colour supplement for birds with yellow plumage – without this captive birds can become noticeably duller and less vibrant than the wild A bank of Regent Honeyeater breeding aviaries counterparts, and is not uncommon in captivity with small passerines that have red or yellow at Taronga Zoo. Photo: Dean Ingwersen pigmentation. Over the course of the recovery program a large amount of work has gone into aging and sexing individual birds and we now have a set of characteristics which are useful for assessing the relative age of Regent Honeyeaters: • Wing feathers. The colour of wing coverts in fi rst year birds is brown compared to the black of mature adults, while the primary feathers of the wing are brown with yellowish markings in immatures compared to the black and yellow tones in adults. • Colour of bare eye patch. The bare skin area around the eye in immature birds is grey-blue in colour, which develops into a pale shade of yellow in mature birds. The facial patch also gets larger as birds age. • Wart development. Immature birds have none to minimal number of warts, - the number of warts increases with age. • Gape colour – a yellow gape indicates a young bird. All these characteristics are benefi cial in assessing the general age of individuals. Data is currently being collected at Taronga Zoo to determine whether facial and plumage developmental changes can provide a more accurate means to obtain the age of specimens. Regent Honeyeaters are capable of breeding in their fi rst year before a full moult, which occurs around late summer-early autumn. Wild Regent Honeyeater nests are usually located in an upright fork of a tree or branch, or within mistletoe at the extremity of branches. Height of the nests can vary from 2 to 20 m, and it is cup- shaped and usually sits tightly within the fork rather than being attached to any part of the limb or branch. To replicate this, large branches with a number of upright forked boughs are placed within the aviaries at the beginning of the breeding season. Typical location of a Regent Honeyeater nest. Photo: Dean Ingwersen. Spider web, dried fi ne grassy material, paperbark, unprocessed raw cotton, goats hair, Emu feathers and other downy type are provided up to twice daily during the breeding season as nest building material. Although both male and female take part in nest building, it’s the female which appears to choose the nest site and does the majority of the nest construction. In captivity, nest construction can be fairly rapid - one female completed a substantial nest within 20 hours! It is not unusual for several nesting sites to be chosen before a nest is fully completed. A pair can spend a number of days building in one site, then totally dismantle it within 24 hours and choose another site. To locate a nest, a keeper often sits within the aviary and watches the nest construction take place. In our experience, the presence of keeping staff does not appear to disturb the nesting activities of the birds. Nest sites are normally located in the highest places within the limits of the aviary, however one female has nested successfully less than 1m from the ground. PAGE 2 Once eggs are laid the incubation period is around 14 days, and begins after the second or third egg is laid. The eggs are incubated solely by the female and is intermittent throughout the day. Some females have been observed to leave the nest for a few minutes up to six times per hour – during this time the male often inspects the nest. Once hatched it’s about another 14 days before the chicks leave the nest. Both male and female feed the fl edglings. If the female re-nests soon after the chicks have left the nest, then the male primarily feeds the young. If the male is injured or unfi t, then the female is the primary feeder. Between the fi rst and second week after leaving the nest, the fl edglings start feeding independently. Fledglings are still dependent on parental care for three to four weeks after leaving the nest. Immediately after this period, it is wise to remove the fl edglings from the adults (especially if the female is re-nesting) since the adult male can become extremely aggressive. In captivity the species readily double clutches - it is not unusual for a female to re-nest and Hopefully the captive breeding program will see lay whilst the fl edglings of the last clutch are still in the same aviary. One female was observed sightings like this, near Bendigo last year, increase actively nest building only three days after two chicks raised by her had fl edged – so much for a in the future. Photo: Chris Tzaros bit of time in daycare!! A clutch of three eggs was later found in a well-concealed nest nine days after the fl edglings had left the nest. Since we’ve been managing the species we have discovered a number of notable breeding behaviours: • The male is more vocal than the female (this is generally seen in the wild too). • The female uses a distinctive vocalisation to obtain a feeding response from nestlings. • After chicks have fl edged they are still dependent on parental feeding for three to four weeks. During this period, the behaviour of the adults, especially the male, towards the fl edglings needs frequent monitoring for aggression.