release successful in re-establishing a population. Techniques and protocols 't Captive Breeding for the are usually refined over a number of years and successive releases. Even I Conservation of once a reintroduced population is looking likely to establish, supplemen­ tation with captive-bred is often 's Endemic Birds required to ensure long-term success. by Glen Holland Once the captive husbandry tech­ Masterson, New Zealand niques have been successfully estab­ lished and documented in a hus­ aptive breeding is usually captive management plan, which is part bandry manual, the next step, and one of the last methods of a species recovery plan and defmes probably the most challenging is to employed by conservation the goal of the captive program. The find sufficient safe habitat and to cauthorities but internationally it is Reintroduction Specialist Group develop successful release methods increasingly used in the fight to save (RSG) is part of the Species Survival for the species concerned. Factors endarigered species from extinction. Commission (SSC), which is in tum part responsible for the initial decline of Captivity is regarded by many as unde­ of The World Conservation Union the species have to be addressed prior sirable and some even advocating that (IUCN). The RSG have produced guide­ to releases. These factors vary signifi­ a species should rather become extinct lines for re-introductions and publish a cantly throughout the world but the than be brought into captivity. Nothing regular update on some of the re-intro­ most common factors responsible for brought this home to me more than a duction programs globally. species declines are human pressure visit to the Californian Condor breeding Single species holdings, .high stan­ and the resulting loss or fragmentation centre managed by the San Diego Zoo. dards of record keeping, husbandry of habitat and the introduction of alien It was explained to me that the fortress­ and hygiene, strict disease screening plant and pests. like appearance of the facility was to and management protocols, researched Another common denominator protect the birds from extremists who release methods, and good post release when looking at endangered species had threatened to kill the birds rather monitoring are now the accepted code on a global scale is the high percent­ than allow them to be held captive. of conduct for captive breeding/release age of island species, often endemic, Fortunately, however, there has in programs. which are in dire straits. New Zealand, recent years been an ever-increasing Captive breeding involves a long­ for example, has lost about 5()O/o of its number of success stories which have term commitment and is an expensive terrestrial species, Hawaii 15 out of calmed the objections of the critics of process. Release sites have to be care­ approximately 50 species and Guam captive breeding. Most recently I have fully assessed and seldom is a single 10 out of 13 species. just read that the American Peregrine Falcon, re-established from captive­ bred birds, has been removed from the threatened and endangered species lists in the USA. Conservation authorities will most often use the option of translocation of individuals from an established, secure wild population to be used as founder members for a new population. When, however, the wild population is already at a low point and can not safely be harvested to provide sufficient individu­ als for translocations, captive breeding, which can be initialized with a handful of founder members, becomes an option. Captive breeding is no longer the hit and miss affair it used to be and the goals of most captive programs are decided on by a recovery group. Ca ptive programs are run - often with expert advice from a taxon advisory Kaka Parrots at the feeding station. group (TAG) - in accordance with a

the aEa WATCHBIRD 49 Animal pests, which impact on the the NWC which have been used for re­ dry season. native species, vary greatly from feral introductions primarily to predator free Further releases are planned for cattle, goats and pigs to monkeys, offshore islands: some years to come with the ultimate mongoose, rodents, and mustelids aim of moving all the birds back to the (, , and ), snakes Campbell Island Teal main Campbell Island. Rats are yet to and introduced birds. Some of these Anas nesiotis be exterminated on the main Campbell introduced species alter the habitat, The wild population of an estimat­ Island. The 99/2000 season has been others compete with native species for ed 20 pairs lives on the remote 25ha exceptional season for the captive food and nests and some prey directly Dent Island which is little more than a population with an expected 16-18 on eggs, nestlings and/ or adult birds. rock stack off the main Campbell youngsters produced (waiting on four The Pacific Rat is on record as being Island. First brought into captivity in fertile eggs as I write) compared to the responsible for more species extinc­ 1984, with a few additional birds usual 8-10 per season. An excellent tions in the Southern Hemisphere than caught in 1991, it took 10 years to pro­ husbandry manual for the species has any other single species or factor. duce the first captive offspring. Unique recently been completed. features of this aggressive species are Decline in New Zealand that they are flightless, largely noctur­ Shore In New Zealand the prime factors nal and produce a small clutch of 3-5 novaeseelandiae for the decline in bird numbers are loss eggs, which are extremely large in The worlds rarest plover (I believe) of habitat and the introduction of rats, comparison to body size. In April 1999 with the wild population of approxi­ opossums, and mustelids. The Mt a second captive population was start­ mately 140 bird is now confined to Bruce National Wildlife Centre (NWC), ed at the Isaac Wildlife Trust in two islands in the managed by the New Zealand .christchurch, and at the same time the group. The initial captive stock was Department of Conservation stands on first 12 birds consisting of six adults derived from eggs sourced from the the ground where the first Takahe and six juveniles were soft released, wild stock in 1991. The husbandry were historically brought into captivity with transmitters, onto Codfish Island. techniques and captive diet for this 1° years after being re-discovered in Following on from 100% survival in species are now well researched and 1948. The primary objectives of the the first six months and some of the proven. Since 1993 In excess of 80 centre are: birds instinctively using the inter-tidal birds have now been released onto • Achieve excellence in research, zone in which to feed, a number of two offshore islands and in the rearing, release, and advocacy (educa­ pairs have separated off and copula­ 1998/ 99-summer season the first tion) objectives for national priority tions have been observed. By mid­ chicks from parent birds originating species November the first clutch of five eggs from the captive-breeding program at • Increase public awareness of the had been laid on the island with four the NWC, hatched on Christmas day. lesser-known threatened species and females eventually producing nine Birds in a new population of 16 birds techniques employed for their conser­ ducklings. All the ducklings perished established, from 26 released over a vation. (Hosts 45 ,000 visitors per as a result of owl predation and a very two-year period, on Portland Island, annum) have also begun nesting. The NWC has pioneered research ~ The plover are released using the into the captive husbandry of a num­ ~ soft release method. Fledglings have ber of species and has achieved a ~ been banded on both islands in the number of first-time captive breeding ~ past season. A recent chemical analy­ for species such as: , Taka­ ~ ses of the captive diet has shown the he, Little-spotted ' and Great-spotted <3 diet to be all but complete with a Q) , Black , Antipodes Island ~ potential shortage of calcium and sele- Parakeet, , Kokako, Auckland ~ nium - both of these are now being Island and Campbell Island Teal, NZ '0 added to the diet as a premix. The hus­ ~ Shore Plover, and -§ bandry manual for this species is well . ~ underway. '0 .c With some of these species (for a.. example the robin and saddleback) it Kaka Nestor meridionalis has been found that translocation (birds In 1996 a mixed group consisting of sourced from existing wild populations) wild caught, captive-bred/parent-raised provides the most cost-effective method and captive-bred hand-raised, juveniles of establishing new populations. were soft released, with transmitters, The past two summer seasons i.e. into the Mt Bruce forest reserve. Once 1998/99 and the present 99/2000 sea­ a day the birds still receive a food sup­ son have produced a number of excit­ plement at the feed stations which ing fIrsts for captive bred birds from New Zealand Shore Plover. allows staff to check on the birds while

50 MarchiApril 2000 ~ pleted and we believe that we are near- 32 ~ ing the situation where we can safely ~ say that if ever the requirement arises, ~ we are able to produce the species in ~ reasonable numbers. Q) ~ The captive population is also to be u ~ used to research techniques, such as ~ artificial nest boxes, which will be '0 ~ applied to the island populations. Q) ~ Although excess birds produced ( 4 u -§ males to date) in the program have it been hard released, this is not a prima- ry goal. It was extremely pleasing to hear however that one of the males released early in 1999 has recently fathered two clutches of chicks, thus A pair of endangered Campbell Island Teal. proving that captive-bred Stitchbird can survive and breed in situ. also providing an excellent advocacy years 14 offspring were produced opportunity with a talk given to visiting which were hard released, with trans­ Black Stilt public. No significant differences were mitters, onto two island sites. In the Himantopus novaezelandiae noted in the field with all the birds 1998/99 season birds bred at the NWC (Information contributed by Richard Maloney adapting equally as well as exhibiting produced chicks on both of the island and Emily Sancha at the Twizel stilt breeding all the natural behaviors expected e.g. release sites. The original breeding pair centre ,) removing insects from rotting logs and have now been separated to allow for The latest release of kaki to the wild taking sap from grooves which they breeding with new partners/genes, the took place on 16 September 1999. In had made in bark. latter of which were the last known total, three adults and 17 sub-adults In the 98/99-summer season, two birds from the Taranaki regional popu­ raised in captivity were released. The females, one a hand-raised three-year­ lation now thought to be close to survival rate from this release has been old bird another a two-year-old captive­ extinction. One of these pairs is looking very high. One sub-adult was found bred! parent-raised bird successfully promising with courtship feeding a dead one day after the release, but the fledged chicks in the forest. Already this daily routine. At least six of the original remaining 19 birds (95 0/0) are all alive season we have one pair incubating in 14 released birds are known to be nest­ two months after the release. and another pair investigating, artificial ing so far in the 99/2000 season. Two changes to the release protocol nest boxes we have placed in the for­ Another new development this sea­ have increased post-release survival est. One clutch of eggs has been son, to develop egg transfer and hand­ from a mean survival rate to adult age removed from a natural nest, which rearing protocols, will be the harvest­ of 29% obtained from 1993 to 1997, to was close to ground level and would ing of 4-6 eggs from nests doomed to the 80+0/0 survival rates presently have resulted in the loss of the female attacked by predators and hand-rear­ achieved. due to mustelids. This female is cur­ ing these chicks at the NWC. These These are (1) all birds receive sup­ rently incubating a second clutch in a birds will also provide new young plementary food for one month after natural nest. They do naturally have stock to be used to support the aging release, and (2) all birds have iodine years in which the birds fail to breed captive population. added to their captive diet pre-release. and this is I believe the only known Supplementary food used is their nor­ active Kaka nest on the North Island Stitchbird Notiomystis cincta mal captive food placed in plates at the this season. This project and release One of three endemic New Zealand release site. Mealworms are initially method which is still in the research honeyeaters, are limited to a added to the plates to encourage the stages could prOVide a valuable re-intro­ Single secure island population on Little birds to feed at the plates. Iodine has duction method for parrots of both a Barrier Island with three relatively new been added to the birds' diet because national and international Significance. island populations initiated with necropsies on dead bodies recovered translocated birds. Only the Little from a previous release in 1998 Kokako Callaeas cinerea Barrier population is considered secure showed that most released birds had One of two New Zealand wat­ at present. The primary objective of the goiter (thyroid dysplasia). Goiter may tlebirds. The primary goals of the cap­ captive program is to research captive not be the proximate cause of death of tive program are saving rare genes and husbandry techniques and disease released birds, it causes a reduction in public advocacy (education), the cap­ issues (particularly coccidia), which the metabolic rate, which may make tive breeding program has been limited affect this species. An excellent hus­ birds more susceptible to predation or to two pairs of birds and the last few bandry manual is currently being com- cold weather conditions. At least one

the afa WATCHBIRD 51 further release will be undertaken at this site, then a new site elsewhere in the will be chosen.

Takahe Porphyrio hochstetteri (Information contributed by Andrew Smart at the Burwood Field Centre) The wild population of approxi­ mately 145 birds (44 known pairs) lives in the Murchison Mountains (530sq km), west of Lake in National Park. The first attempts at captive rearing started in 1957 at Mt Bruce. Over a period of 18 years, four eggs, six chicks and 17 adults were removed from the wild population. It wasn't until 1972 that the first fertile egg was produced and only four chicks were raised to indepen­ dence by 1983. The hand-rearing pro­ gram began in 1983 at the Te Anau Wildlife Park. The basic methods used then are still the cornerstone of today's techniques. After this initial success it was decided that a purpose built Takahe hand-rearing facility should be built at Burwood Bush. This was com­ pleted in time for the 1985/86 breeding season. The facility is designed to accommodate incubation and hand rearing of up to 20 chicks per breeding season. This season we have 15 chicks at Burwood and approximately a dozen in the wild. The Burwood chicks are held for approximately one year, when they re-introduced into the wild population. The survivorship of our re-introduced birds to one year after release is high (710/0, n=58). Ninety-six Takahe have been released into the Murchison Mountains since November 1991. Of these 23 are known breeders. Prior to this the hand-reared Takahe were released on a number of offshore islands and in the Stuart Mountains. The off-shore Islands were set up as an insurance population (now approximately 60 birds on four islands) in case of some­ thing-catastrophic happening to the wild population. The Stuart Mountain population was started as an attempt to establish a new population in the next mountain chain north of the Murchison's. Fifty-eight Takahe were released in the Stuart's until 199.2 when it was discontinued due to a low resighting rate. ~

52 Marchi April 2000