INTERNATIONAL ZOO NEWS

The breeding results of captive musk oxen (Ovibos moschatus wardi) are poor. Four musk oxen are currently held at Berne Animal Park. Twenty-one calves have been born in Berne since 1987, but only seven of these have survived; 11 calves died within one month after birth. The latest calf, born in 1997, suffered from diarrhoea, and a massive Strongyloides papillosus infection was found during the parasitological examination of its faeces. The whole herd was successfully treated with Ivermectin and Fenbendazol.

The musk oxen are kept by themselves in one enclosure, and no new animals have recently been imported. The infestation of this herd with S. papillosus had not been noticed before, despite parasitological and post-mortem examinations. Faecal material of adult musk oxen was examined separately from that of the young in this case. Adults did not show any clinical signs of infection except itching, nor was the S. papillosus found as often in faecal samples of adults as calves. Investigation of separate faecal samples from new-born animals and adults is recommended.

S. papillosus can only be diagnosed through the presence of eggs containing the distinguishing embryos. Faecal samples gathered two days after the faecal sample containing the eggs yielded only larvae. The larvae are impossible to differentiate from other nematode larvae with the normal praxis methods used, flotation and sedimentation. This means that time of examination plays a significant role in the diagnosis of S. papillosus infections. Young animals are the most severely affected by the infection; the parasite is known to cross the placenta and infect calves before birth, or pass via colostrum to new-born calves. Whether S. papillosus infection was one of the causes of the high calf loss remains unresolved. In any case, potential infections by this parasite should be given consideration in the future in the captive breeding of musk oxen.

Hanna Tenhu and Bernd Schildger in EAZA News No. 23 (July–September 1998)

The zoo is to be the recipient of one of the most exciting ventures ever to hit the Internet. The Online Aquarium is currently being created as a gift from Bristol's multimedia and arts community. In every way it is a `next generation' website module. The project will not only invite more visitors to enjoy an educational and entertaining trip to Bristol Zoo, but will shine a spotlight on Bristol's interactive media community. Due to be unveiled in September, the website module breaks new ground technologically, containing material never before seen online. Instead of the Internet's usual text-heavy pages, the Online Aquarium will be presented as a 3D graphical environment. Visitors will be invited to `swim' through waters containing both ocean and river species, all of which are currently housed at the zoo's aquarium, reflecting its important conservation work. The online fish are being created from a variety of source materials including film, video, paintings, and computer-generated images. Some of the fish will talk about themselves, providing both education and entertainment. Children's games based on identifying fish will also be featured.

Designed to meet the zoo's needs, the online gift has been conceived primarily as a showcase for the extensive amount of interactive media talent centred around the Bristol area. It is a true community effort, and organisations involved in the project include the BBC's Natural History Unit, Hewlett Packard's research and development laboratories, and the University of the West of England's MediaLab.

A successful enrichment device was a log `raft' constructed to simulate an ice floe in the pool area of our 26-year-old female polar bear. It is constructed from four 30 cm by 244 cm logs loosely fixed side-by-side with cable. A chain attached to one corner below the water line is secured to the pool edge, keeping the raft tethered to provide an anchor, some mobility, and a safe distance away from any viewing windows. The top surface of the logs is planed to provide a flat and steady surface. The raft lists under the animal's weight, providing a launch point or access out of the water. The mobility (drifting) of the logs creates uncertainty where it will be positioned at any time. Behaviors initiated includes stomping, launching, pushing, sunning, eating on, and swimming under the raft.

Adapted from William Blayney in Animal Keepers' Forum Vol. 25, No. 7 (July 1998)

Emi, the zoo's Sumatran rhino, has miscarried again. Her first pregnancy last year was lost at about day 40, apparently due to embryo implantation failure. Although implantation appeared successful at day 80 in this second pregnancy, and zoo staff were hopeful that she would go to term, an ultrasound examination on day 94 revealed that the pregnancy was lost.

While the loss is indeed disappointing, both keepers and scientists from the zoo's Center for Research of Endangered Wildlife (CREW) are encouraged by the fact that their breeding strategy was successful after the termination of the first pregnancy and that it resulted in a second pregnancy. `When trying to propagate endangered species, getting the animals pregnant often is a big challenge,' says Dr Terri Roth, director of CREW, `and we appear to have learned how to do this with our Sumatran rhinos. Now, it seems we must face a second, less familiar challenge in getting our female to carry a pregnancy to term. One thing is certain – we are not giving up!'

The aquarium's education department has received two critically endangered Orinoco crocodiles (Crocodylus intermedius) from PROFAUNA, the Venezuelan Ministry of the Environment. Both animals were confiscated by the Venezuelan authorities and determined to be unsuitable for release back into the wild. Their population has been drastically reduced by overhunting, loss and change of habitat, and pollution of waterways. The aquarium has been involved with conservation programs for the Orinoco crocodile for the past two years. Thirty breeding adults from four facilities are producing more than 300 offspring for release into the Orinoco River each year. In addition to support staff assistance, a portion of daily admissions is given to PROFAUNA for the Orinoco Crocodile Managed Breeding Program.

S. Kienitz in AZA Communiqué (August 1998)

Seven Malaysian painted terrapins (Callagur borneoensis) hatched at the zoo between 9 and 23 June from a clutch of 12 eggs laid on 1 April. The zoo has worked with Callagur since 1991, and the breeding group currently consists of 1.8 adult turtles. This is the first species to reproduce in the zoo's Komodo dragon/gharial complex, which opened in 1995 and also houses Philippine crocodiles. One of the most threatened and heavily exploited of the large Asian river turtles, there are 34 (9.21.4) Malaysian painted terrapins held in seven AZA institutions. The species has been bred previously at the Bronx and Columbus Zoos.

Rick Hudson in AZA Communiqué (August 1998)

Jersey Zoo's latest breeding achievement means that there is hope for the survival of one of the world's rarest species of duck, the Madagascar teal (Anas bernieri). On 8 July 1998 a clutch of six eggs hatched at the zoo, the first recorded breeding of the species in captivity and the first time that `live' eggs of the teal have been seen. First described in 1860, the Madagascar teal was `re-discovered' in the 1960s. A survey in 1973 showed that the duck was under threat, but a 1992 expedition discovered that the situation had worsened and the species was approaching extinction. It was recommended that further survey work, an education programme and a captive-breeding programme be started. In 1993 and 1995 eight (6.2) birds were captured and sent back to Jersey Zoo. With the exception of one bird in the 1920s, these were the first to be kept in captivity.

In Madagascar, with the support of the local government, the Trust is employing a scientist, Richard Lewis, to try to learn more about the natural history of the teal [see I.Z.N. 44:6, pp. 369–371 – Ed.], and has initiated a village-based education programme in the vicinity of the teal's habitat.

Recognising the sensitivity of wild-caught animals to life in captivity, an innovative enclosure was created in a wetland area of the zoo, where the public would be able to view these secretive creatures from hides without disturbing them. The large, landscaped aviary was completed in March this year, allowing two pairs of teal to be housed together. Eleven artificial nest sites were provided, consisting of various boxes at different heights above the ground and hollowed tree trunks. The ducks became increasingly aggressive and territorial, as the stimulus provided by their proximity to each other obviously inspired them to consider breeding. The first egg was laid in early June, and incubation began on 13 June. With considerable apprehension, the eggs were removed for artificial incubation to ensure their safety and encourage further laying. After hatching, the precious ducklings have progressed well. The parents also laid a second clutch which hatched on 14 August. Four of these six are being reared artificially, but the other two are with their parents in the aviary and can be seen by the public. Even better news is that the other pair have also laid; six fertile eggs were artificially incubated, hatched on 1 August and are now being reared artificially.

Another rare species which has bred at the zoo this summer is the Round Island boa (Casarea dussumieri). Collected in 1977 and 1978 on Gerald Durrell's expeditions to Round Island, near Mauritius, these unique and highly endangered snakes have always been very difficult to keep and breed in captivity. Jersey is the only zoo in the world to have bred them; but success during the 1980s came to an abrupt end in 1990, the last time boas were hatched at the zoo. Thereafter, all eggs were either infertile or failed to hatch. Over the past four years many modifications have been made to the boas' diet, accommodation and seasonal environment in an effort to stimulate renewed breeding vigour. Additionally, monthly ultra-sound scans were carried out for two years on all the females, to develop a better understanding of their reproductive cycles and identify when individuals were ovulating so that they could be introduced to males. The final piece in the puzzle was the supplementation of calcium and vitamin D3, both essential substances for the production of healthy eggs and offspring. Vitamin D3, which many other animals, including humans, synthesise through exposure to sunshine, controls the metabolism of calcium in the body. Without D3, eggs and their embryos will not receive sufficient calcium reserves to build strong healthy babies. On 1–2 August 12 out of a clutch of 13 eggs successfully hatched. The babies are minute, about 20 cm long but weighing only 3–4 g. At the time of writing (7 August), 22 more eggs from three other clutches are still in the incubator and are expected to hatch over the next six weeks.

We have several species of primates, including siamangs, white-handed gibbons and spider monkeys, who are housed and displayed on islands in the center of man-made lakes. These outdoor, open-air exhibits have presented challenges to keepers in ensuring that their exotic charges do not have to compete with the native wildlife for food. Native turtles, ibises and geese (among others) have been constant competitors with these primates for their daily food rations.

To aid in overcoming this problem, we designed a simple feeder box that sits on a platform at the edge of each island and allows for (a) easy access for both the primates and the keepers, and (b) not so easy access for the native wildlife. The box is constructed almost entirely from four-inch (100 mm) fence boards, and has a lockable hinged door in the rear that opens to allow for keeper access. The front of the box is made from standard wire utility shelving that has had three three-inch (75 mm) gaps created by snipping out appropriate wires. Another section of wire shelving serves as a shelf within the box to hold the food container. The shelf slants down towards the front of the box, allowing easier access for the primates. We use new cat litter pans for the food containers.

Large eye screws placed on the sides of the box and on the edge of the platform are capable of holding palm fronds or browse material; they can also be used to secure wire puzzle boxes. We have found that large food items (whole lettuce heads, half melons, etc.) create a little more of a challenge for the animals to access through the three-inch gaps, making an easy method of enrichment.

Whereas at one time feeding was a stressful, competitive event, it is now a much calmer, more relaxed affair for all involved. All of our primates have utilized these feeder boxes with great success. Not only have we noticed a marked improvement in their food consumption, but it has also allowed us to more accurately assess their likes and dislikes. A secondary effect has been an improvement in their social behavior. As they are now able to retrieve food at their leisure throughout the day, aggression has been markedly reduced and positive social interaction, including grooming and play behavior, has increased. We highly recommend these feeder boxes to anyone who has met with similar feeding problems.

Tina Fridman and Paul Rambino in Animal Keepers' Forum Vol. 25, No. 8 (August 1998)

Monkey World received one of this year's UFAW Zoo Animal Welfare Awards for the new `Woolly Monkey Habitat' enclosure. One unusual and stimulating feature of the enclosure is the inclusion of several herb gardens. These encourage the inhabitants to display a surprising pattern of behaviour. In the wild, it has been shown that some species of primate hunt out specific types of plants to treat a range of health problems. For example, chimpanzees have been shown to select and prepare leaves of certain plants to deal with internal parasite infestations. The herb garden offers the woolly monkeys the opportunity to practise such behaviour, although it is probable that the monkeys are using the herbs simply as tasty additions to their regular diet. Garlic, chives and camomile are proving particularly popular.

This herb garden is not the only imaginative addition to which the woolly monkeys have access in their new enclosure; a range of fallen trees and rotting bark chippings provide them with ample opportunities to forage for highly sought-after beetles and grubs which they eat with relish.

Alison Cronin, Scientific Director for Monkey World, which rescues ill-treated and badly-kept primates throughout Europe and houses them, says `We are very happy with the housing. We researched the requirements of the monkeys extensively before we started to design the housing, to make certain that we offered them an appropriate and stimulating environment. Indeed, the older female Xuzy has slimmed-down considerably since being introduced into the enclosure, is more active and is now seen regularly playing with the youngsters.' The zoo is hoping for births soon.

The award will be presented to Monkey World by Jane Goodall.

For the fifth consecutive year, the National Aviary is participating in the Khinganski Nature Preserve project to raise and release endangered red-crowned and white-naped cranes back into the wild. Eggs from across the United States were collected at the aviary on 16 May and sent to Russia to be hatched and released into the cranes' native environment. There are currently only 4,700 white-naped cranes and less than 2,000 red-crowned cranes in the world. Eggs from Memphis Zoo, Oklahoma City Zoo, Franklin Park Zoo and the International Crane Foundation arrived at the National Aviary. Seven red-crowned and three white-naped crane eggs were sent to Russia on 18 May.

R. Mohr in AZA Communiqué (August 1998)

The zoo was joint winner with Monkey World of this year's UFAW Zoo Animal Welfare Awards for its `Marie Le Fevre Ape Centre', and also won the UFAW Innovation Award for its artificial termite mound for birds – the first time that any zoo has won both awards in the same year.

The Marie Le Fevre Ape Centre, which houses Bornean orang-utans and western lowland gorilla, includes many interesting and stimulating features. It provides the apes with large outdoor islands that they can explore and two spacious, structurally-complex indoor quarters. An attractive aspect of the indoor quarters is the superb view of the outside world it gives to the public and, more importantly, the apes. Neil Bemment, Curator of Mammals, says `During inclement weather the apes spend a large proportion of their day indoors. This design with its panoramic views provides them with mental stimulation when they are inside.' The enclosure has also been designed to encourage the orang-utans to move about in the trees and on the aerial walkways provided, the commonest way they travel in the wild. Keepers hide food around the enclosure and give the apes food in puzzle boxes, which they have to solve, as a way of keeping the animals active.

The Innovation Award recognises an innovative piece of equipment that enhances zoo animal welfare. The artificial termite mound in the Desert House aviary provides the avian inhabitants with a random supply of mealworms and keeps the birds guessing as to when the next piece of food is going to arrive. The hooded parakeets liked the design so much that they have taken up residence in another mound specially built for them. Dr James Kirkwood, UFAW's director, says `This is a simple but ingenious design, and one that can easily be copied by other zoos. It shows that enriching the lives of animals requires imagination but not necessarily large amounts of money.'

The zoo has been very successful in breeding pink-backed pelicans (Pelecanus rufescens) over the past years. Sigean started to keep this species in 1974, when 15 birds were imported from the wild. The group, which had increased to 59 individuals by the end of 1997, lives in semi-freedom on and around a ten-hectare lake. Thanks to the mild Mediterranean climate of southern France, the pelicans can stay there all year round. Approximately 60% of the birds are pinioned, which has proved to be sufficient, as none of the full-flighted ones has left the zoo.

The first chicks were reared in 1980 and the pelicans have bred regularly since then, except during the years 1984–1987, which was probably due to the long and cold winters (temperatures below 0° C for several days) and the high water-level of the lake. Human contact or interference has been restricted to the absolute minimum since the establishment of the colony. No eggs are collected or artificially incubated, and all chicks are parent-reared. A total of 76 pelicans had hatched by the end of 1997, of which 54 have survived. Most of the young hatch between July and September, but some also in May and November. The youngsters begin mixing with the adult birds during the daily feeding sessions and collecting their own fish when they are two months old. The pelicans are fed thawed frozen fish – mackerel (Scomber scombus) and bogue (Boops boops) – once a day. Furthermore there is plenty of live fish (mainly grey mullets Crenimugil labrosus and Mugil saliens) in the lake, which the pelicans catch themselves.

Frédéric Tardy in EAZA News No. 23 (July–September 1998)

The zoo had an exceptional breeding season in 1998 with the waders: 137 chicks of seven different species were reared.

The pied avocets (Recurvirostra avosetta) contributed 61 young to the total. As there is a decreasing demand for avocets in zoos, our strategy was to leave the pairs with their clutches for natural incubation, and to take away the hatchlings, or the eggs shortly before the expected time of hatching, for artificial rearing. Natural rearing is almost impossible because of the large mixed population of waders in our shore-bird aviary. Birds defend their territories so fiercely that it is impossible for the young, guided by their parents, to reach the food and to withstand attacks. Rheine has been breeding avocets for more than 25 years, and only four new birds have been introduced in recent years. However, we have never experienced problems with inbreeding, and this year we had only three infertile eggs out of 83 laid.

Two pairs of black-winged stilts (Himantopus himantopus) delivered three clutches each. The stilts, too, brooded by themselves and we transferred the eggs into the incubator a few days before their expected hatching. With the same incubation conditions as for all the other waders, we had the worst success, and 12 chicks died during the process of hatching. In the end we only reared three stilts.

The ringed plovers (Charadrius hiaticula) produced three consecutive clutches with 100% fertile eggs. Brooding was done by the birds and rearing artificially. However, the first three chicks died during their first days of life, presumably as a result of mixing with other young waders. We experienced no rearing problems with six hatchlings who were kept on their own or mixed with young spurred lapwings (Vanellus spinosus). The latter species produced two clutches of three eggs each. A hatchling of the first clutch developed deformed legs after several weeks and had to be euthanized. Two young of the second clutch developed well. The European lapwings (V. vanellus), too, produced two clutches and all the hatchlings of the second one grew up perfectly.

With the redshanks (Tringa tolanus) and ruffs (Philomachus pugnax) we removed all the eggs we found for artificial incubation. Seven redshanks, assumed to be 4.3, produced 32 eggs, and only two of these were infertile. Thirty young hatched between 15 May and 12 July, and only three died during the first weeks. In past years too we have experienced by far the least problems in hatching and rearing with the redshanks. This does not mean that we do not have to care for them: the young ones obviously need some privacy, and we offer them hiding places in the rearing-boxes and nursery aviaries.

In the light of our experience and the general opinion of various keepers, ruffs are among the most difficult waders to breed and especially to rear. Rheine Zoo has done some husbandry research with this species in recent times, and we have come to the conclusion that ruffs are highly sensitive to stress and disturbance in the first weeks of life. The adult birds, by contrast, are quite resilient and cause only minor maintenance problems. After this breeding season we think that we are a step nearer to achieving successful rearing methods, but we are still far from being able to present guidelines for the species. We reduced disturbance even in the incubator to a minimum, checking the eggs only twice a day. Humidity was kept high at about 80% around the time of hatching. The boxes for the ruff chicks were decorated with bunches of grass and covered with leafy twigs to provide `natural' surroundings with places to hide and to feel secure. Dark green towels were used as floor covering, as we had the impression that even white towels and bright surroundings disturbed the chicks. All the ruff chicks were kept off-exhibit for the first weeks of life, and the keepers went in to clean and feed them only twice a day at fixed times. We gave them the same food as we use for other young waders, composed mainly of a mixture for softbills, with some shrimp and very small amounts of meat and commercial dog-food. Cooked noodles and egg-yolk are special treats, as are small amounts of mealworms.

So the summing-up is as follows. Our 14.17 adult ruffs produced 106 eggs, all but three of which were incubated artificially. Ten were infertile, 33 died during incubation, six died during hatching and two immediately after hatching. Fifty-two ruffs hatched and three more were found in the aviary and transferred for artificial rearing. Twenty-one of these 55 hatchlings died. As in previous years, we experienced the `twisted-neck' symptom with seven young; this occurs suddenly and is not reversible. Eight died as a result of being kept in a group with too many young birds together. So our recommendations for rearing are to reduce disturbance to the lowest possible level, not to mix young ruffs with other wader species, and not to keep too many individuals together in the first weeks of life (four might be a limit). The 34 ruffs reared are certainly the best breeding success yet for this species in captivity. Keepers of ruffs need to cooperate and work seriously with this species to establish long-term viable captive populations.

Two (0.2) Asian golden cats (Catopuma temminckii) were born on 13 March 1998; they are being mother-reared and are doing well. The father was separated from the female before she gave birth. The birth of more than one kitten in a litter is rather rare in this species; it is estimated that it occurs only once in about every ten litters. The low birth rate of this rare species makes every birth a significant contribution to the EEP population. The breeding pair, originating from China, arrived in Wassenaar in May 1995 on loan from Rotterdam Zoo. The female gave birth to a single male offspring in April 1996 and another in April 1997, but only the latter survived. Golden cats from China differ from South-east Asian ones by the remarkable ocelot-like spots and markings on the chest, belly and thighs. Some taxonomists consider this patterned form a separate species, while others classify it as a distinct subspecies (Catopuma temminckii tristis) of the Asian golden cat.

Jan Louwman in EAZA News No. 23 (July–September 1998)

The 1998 breeding season proved exceptional for the centre, with four species – Moffitt's Canada goose, bronze-winged duck, African black duck and Pacific black duck – breeding for the first time in our history. In addition several species which had not bred here for nearly a decade produced eggs, including Chilean flamingo, lesser Magellan goose, ashy-headed goose, Orinoco goose, coscoroba swan (two pairs produced six cygnets) and New Zealand brown teal.

Other notable breeding successes were greater flamingo, black swans (three broods from one pair), fulvous whistling duck, Cape, ruddy, Australian and paradise shelduck, blue-winged, Andean, greater Magellan and ruddy-headed goose, cereopsis, Patagonian crested duck (20 offspring from three pairs), marbled teal, Cape teal, Chilean pintail, New Zealand shoveler, eider, New Zealand scaup, lesser scaup, goldeneye, goosander, hooded merganser, smew and white-headed duck.

New to the collection were 1.1 black spurwing, 1.1 South American comb duck, 1.1 lesser Magellan goose and 1.1 Orinoco goose. A second trio of magpie geese arrived. During the year we opened a new Summer Walk, the second phase of our Pond Zone teaching area, and new pens for South Georgia teal and for African waterfowl. On the reserve, 20 broods of tree sparrows were raised thanks to nest-boxes provided by Community Services workers; this is a great achievement considering the big decline in this species nationally. Surveys have also revealed over 2,000 species of invertebrates and 300 of fungi on the site, and several rare species of plant were also discovered this year.

A pregnant Asian elephant at Dickerson Park Zoo, Springfield, Missouri, U.S.A., is the first confirmed elephant pregnancy resulting from artificial insemination. The cow was inseminated on 25, 26, and 28 January and is due to give birth in November 1999. The pregnancy has been confirmed by blood tests indicating elevated progesterone levels and by reproductive tract ultrasounds.

J. Glazier in AZA Communiqué (August 1998)

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Two groups of male prairie dogs have been introduced into a new exhibit at Knoxville Zoo, Tennessee, U.S.A. Using operant conditioning techniques, the animals are trained to enter a crate for daily health checks and positive identification. Each training session is videotaped for data collection.

G. McMillan in AZA Communiqué (August 1998)

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A two-pound (0.9 kg) Speke's gazelle was born at the National Zoo, Washington, D.C., on 27 March. The female baby is healthy and growing quickly. As of 31 December 1997, only 35 Speke's gazelles lived in six North American zoos. This is the third Speke's to be born at the National Zoo.

Zoogoer Vol. 27, No. 3 (May/June 1998)