History of Jersey Zoo & Durrell Trust ex-situ / in-situ conservation efforts.

Thanks for sharing @Zorro !

That is interesting, I knew that there had been BLT at one Australian zoo but I didn't know that it was at Adelaide.

I think what may have happened is that they struggled to breed them ex-situ as these are a very hard Leontopithecus species to breed in comparison with the golden lion tamarins and the golden headed lion tamarins.

Once the population held had at died out they decided on not obtaining anymore possibly due to the difficulty of keeping but also due to difficulties of obtaining them from Brazil.

In that sense I don't think Adelaide were alone as the same decision seems to have been taken at the other UK zoos and the US, German and French zoos that also held them.

 

I believe there were a couple of other species brought in at that time including the Golden headed species!

 

The golden headed lion tamarin is very much the opposite of the black lion tamarin.

I think they are probably the most resilient of all of the lion tamarins and they tend to be really good breeders in zoos also the least endangered of the Leontopithecus in the wild.

Is this species still kept within Australian zoos ?

 

As far as I am aware Adelaide was the only zoo to have held them!

 

I take it that they no longer do ?

 

No not for quite a few years now!

 

Sorry about my terrible grammar / punctuation in my replies to your comments by the way.

I was just looking at some of my earlier comments and they are riddled with mistakes.

Really embarrassing actually.

 

It seems that these too died out in Australian zoos then which comes as quite a suprise.

I bet there are still golden lion tamarins held somewhere in Australia though.

 

Yes there still are the Golden Lion Tamarins in a number of zoos within the region also now in some of the smaller regional zoos. There are 6 species of callitrichidae within the region with I believe one or two more species that maybe yet to be imported!

 

Doesn't suprise me about the golden lion tamarin as these are probably the most common of the lion tamarins kept in captivity with the golden headed lion tamarin a close second.

 

Background to the reintroduction of the BLT



In 1997 Jersey zoo partook in a bold new initiative with the conservation of the black lion tamarin:

"Following the second PHVA held in 1997 (Bailou et al.,1997), the committee decided to implement a new conservation initiative based on the metapopulation theory and also on the plan envisioned by Cláudio Valladares-Padua, Instituto de Pesquisas Ecológicas (Institute for Ecological Research) in Brazil and Jon Ballou of the National Zoo, Washington DC."

"Under this programme, all known populations of black lion tamarins are treated as subpopulations of a large metapopulation managed as one whole within an integrated plan. The captive populations are treated as one subpopulation, known as the “nucleus” subpopulation (Valladares-Padua and Cullen Jr, 1994; Ballou and Valladares-Padua, 1997). The objectives of this management strategy are to maximise the survival probability for the taxon as a whole and to increase survival probability and adaptive evolutionary potential for the metapopulation in nature."

"These metapopulation management transfers include translocations, reintroductions, and induced dispersals. The last are designed to mimic a natural dispersal event and depend on the transfer of one or more individuals from their original group territory to that of another group."

According to this newly formulated plan arranged with Brazil seven Jersey tamarins would be reintroduced to the wild and integrated within wild groups of the species:

"The first reintroduction of a group of black lion tamarins composed of wild and captive-bred animals, which we call a mixed reintroduction group. This was done on the assumption that captive-born members of the reintroduced groups could learn the adaptive behaviours necessary to survive in the wild from their wild group-mates, thus increasing the probability of a successful outcome. This approach differs from other reintroduction programmes conducted for tamarins such as the one devel oped for the golden lion tamarin Leontopithecus rosalia, because we are reintroducing mixed groups of wild and captive individuals instead of whole groups of captive-born animals."

Build up to the reintroduction attempt



The Jersey group had been living free-range within the "tamarin woods" area of Jersey zoo for two years where it was hoped they had picked up valuable skills in order to facilitate the reintroduction attempt:

"The group from which it was decided to take animals for reintroduction was a free-ranging family of seven individuals from the Jersey Zoo, headquarters of the Durrell Wildlife Conservation Trust. The group had been living free in a wooded area of the zoo for two years, and consisted of a breeding pair and five offspring."

The group had been carefully studied during this period to ascertain their suitability for reintroduction:

"The group had been studied during their adaptation to a free-ranging lifestyle (Evva, 1997; Detert, 1998), and data had been col lected that were comparable to those collected on wild animals. This environment gave the animals the opportunity to develop skills which would help them survive once released into the wild – foraging, hunting, orientation in a complex three-dimensional habitat, and group cohesion over a large area. Their range after two years covered approximately 100 x 50 m, and they had formed interesting mixed species associations with groups of silvery marmosets Calllithrix a. argentata and Goeldi's monkeys Callimico goeldii."

Even at that early stage some of the individuals showed great potential :

"Studies of the group immediately follow ing release (Evva, 1997) and one year later (Detert, 1998) showed that the eldest male off spring (the zoo staff named him Marco), two years old at the time of release in 1997, was the most adventurous, developing the largest range and typically being the first to enter a new area. Younger offspring also ranged rela tively large distances, but the older female off Spring and the parents tended to remain much closer to the group's shed."

At the build up to the reintroduction some individuals of the group were discounted due to health reasons:

"The breeding male, who was relatively old, had been declining in health for some time, and died in June as a result of a perforated gall bladder. The breeding female proved to have an abnormal blood picture, and as she was ageing, it was decided not to send her to Brazil. Neither she nor the breeding male would in any case have been selected for reintroduction."

However, the offspring of the breeding pair proved to be suitable and were therefore sent to Brazil:

"Only the five offspring were therefore exported, and for the initial release, the two males, aged 2 years 3 months and 4 years in July 1999, were selected, the three females remaining at the Rio de Janeiro Primate Centre (CPRJ) to be reintroduced at a later date."

BLT back in Brazil



The wild group that would be part of the effort were carefully selected :

"The wild group selected for the project occupied a home range of about 150 ha within MDSP. It was initially composed of five individuals: two females (one adult and one subadult) and three males (one adult and two subadults). The subadult animals weighed between 400-500 g and were one to two years old (Table II). This group was selected for three main reasons: a) it had been monitored since 1998 (with few interruptions),b) it occupied an area with abundant fruit and water, and c) the home range area for this group was in terrain that easily allowed researchers to follow and monitor the group."

The plan was to capture these and transport them to the Rio de Janeiro primate centre where they would be introduced and mixed with the Jersey tamarins:

"The plan for this group was to reintroduce the wild females mixed with the captive males from Jersey, to transfer one adult male to the Rio de Janeiro Primate Centre to become a new founder and to use the remaining two wild males in an induced dispersal experiment at MDSP."

"On 1 July 1999, the three wild animals select ed from the five captured, using a protocol described by Valladares-Padua (1993), were transported together to Rio de Janeiro. The Jersey group arrived in Brazil on 2 July 1999. Both groups were housed in CPRJ in open-air enclosures (6 m x 3 m x 3 m) containing a nestbox, suspended feeders, and two branches fixed horizontally."

The tamarins both Jersey and wild-caught were carefully introduced to one another at the centre in the hopes that there would be successful mixing:

"The mixing of the two wild females with the Jersey males took place on 10 July 1999. This was potentially a time when aggression could have occurred, particularly between the two males. The males were separated from their sisters and placed directly into the females’ enclosure. The group was then observed for several hours. The females were clearly still very timid and stressed from the handling and move, and spent most of the time inside the nestbox. The older male entered the nestbox first, the younger male appearing more stressed by the situation, moving rapidly round the enclosure, calling frequently and appearing fearful of observers. No aggression was seen and the animals spent most of the observation period in the nestbox."

Unfortunately a tragedy occurred at this point with the death of one of the Jersey males:

"Because of the possibility that disease was present in some primates at CPRJ, more blood tests were needed before the animals were moved to the reserve. During restraint for blood sampling on 13 July 1999, the younger Jersey male collapsed and died as a result of respiratory problems. This was almost certainly stress induced."

It was therefore decided that only one of the Jesey tamarins would initially be released, the surviving male:

"The decision was taken to release the older male alone with the two wild females, and on 16 July 1999 the group was captured, placed in a travelling crate, and transported to MDSP by air."


Photo credit @Javan Rhino and @Indlovu.

Source: "Preliminary evaluation of the reintroduction of a mixed wild captive group of black lion tamarins Leontopithecus chrysopygus", CLAUDIO VALLADARES-PADUA et al, 2000 (Journal: The Dodo).

 

M2332 arrives at Morro do Diabo National Park



The male who was given the name "M2332" was therefore to be the only one of the original seven Jersey tamarins to be reintroduced to the Atlantic rainforest of Morro do Diabo National Park (MDSP) in São Paulo state.

The mixed group which he was now part of had been transported to the National park and were now held ex-situ in enclosures:

"At MDSP, the mixed group remained for 21 days in an enclosure measuring approximately 4.5 m x 3 m x 3 m and constructed of concrete and mesh. A third of the area had a roof cover. Environmental enrichment in the enclosure included horizontally and vertically positioned branches, hanging bamboo, two hollow logs, swinging bamboo poles to which pieces of fruit were attached, and foraging boxes where food was hidden. This arrangement was beneficial in maintaining the animals' fitness and keeping them foraging for natural foods."

The group were carefully observed by researchers during this adjustment period :

"During this time, we conducted daily observations to evaluate the development of interactions between the females and the male, and the male's reaction to new food items offered. We offered native food items includ ing small jerivá palm fruits Syagrus romman zofianum, Coleoptera larvae, tree-frogs, and ripe fruit Celtis spp. Initially, the male did not accept novel fruits offered to him, although animal food items were well received and he already possessed adequate foraging behav iour for animal prey. After one week, the male tasted fruits from Syagrus rommanzofianum, but preferred more familiar items (banana, apple, grape)."

The integration of the Jersey male to the group worked...somewhat :

"The following week, the females initiated grooming behaviour towards the male, which led to an episode of erection. The older female obviously solicited the male, but no mounting behaviour was observed."

Radio-transmitters were soon fitted to the animals and they were eventually released :

"During this week, on 26 July, we captured the animals to fit radio transmitters. The radios (Telonics and Wildlife Materials) were attached to a ball chain collar and weighed about 15 g."

The release of M2332



"The mixed group was released in a forested area of MDSP. The release site was chosen according to the fol lowing criteria: it was within the original home-range of the wild group; the under growth was not dense, facilitating the move ment of researchers during the tracking of ani mals; the area had a relatively high density of potentially fruiting trees; and shelter trees were present, including tree holes previously used by the wild females. As during the crucial time immediately after release, the females may have left the male, it was also important that the area contained well-connected tree cover and plenty of aerial routes to allow him to keep up with them."

"It was decided that the animals would be placed, during the night, in a tree hole previously used by the females (Plate 3). This was done so that the females would be well oriented and able to move comfortably the following morning, something that was also favourable for the captive-bred male. The animals were caught up and moved in bags by car to the release area. They were placed in the tree hole at approximately 2000. There was some concern that they would flee the hole, which would make them extremely vulnera ble, but fortunately they stayed silent and remained inside. The following morning at 0500 we returned to the site, and began observations of the group."

However, M2332 encountered difficulties during his first day as a truly wild tamarin:

"Following sunrise, the male left the tree hole at 0700 and observed the researchers. The females only exited at approximately 0800. They vocalised toward the male and then began moving quickly, without stopping, and the male followed them. We accompanied the group at a distance of about 20 m so as not to frighten them. The male was able to follow the females until the afternoon, when he lagged behind and became lost. We captured the male by hand, attracting him with a piece of banana. Release site (sleeping tree) of the and placed him in the same hole chosen by the black lion tamarin mixed group at Morro do females to spend that night."

However, things began to improve in the subsequent days:

"Thereafter, we accompanied the group at a greater distance (50 m), only observing the animals occasionally, to minimise the risk that the females would flee and leave the male. Although the females were habituated to the researchers, in a new situation they would travel fast, leaving the male alone. As the three animals were radio-collared, we were able to monitor them individually and to locate the sleeping sites every day. The group received supplemental feedings during this initial period of 10 days – fruits were placed by the sleeping hole selected by the group after they had retired for the night. The male was able to remain near the females, and on only three occasions out of 10 did he sleep in a location away from them, at a distance of 10 m or more. Each time he managed to relocate the females in the morning."

This continued until an unexpected period of cold weather almost took the life of M2332 and it was decided to place him once more into captivity to allow him to recover before attempting a re-release:

"Unusually, however, the weather had turned very cold (about 10°C) and on 16 August 1999, the male's radio signal was not heard first thing in the morning after a partic ularly cold night. A weak signal was finally detected at 1200, and we eventually decided to move closer at 1600. We discovered the male on the ground, weak and very cold, and opted to recapture and maintain him in captivity until he recuperated. It is likely that if we had left him, he would have fallen prey to a predator. The females remained free. The male was returned to the enclosure at MDSP and examined by a veterinary surgeon; he was dehydrated, but had lost only two grams from his pre-release weight of 727 g. Intensive efforts were made to observe the females closely during the male’s period of recovery, so that the group's progress could be properly monitored without the females fleeing, and 13 days later, he was re-released."

"The male was put in a tree hole again, together with the females. For a time, supplementary food was placed during the morning near the entrance to the hole used during that night. Both females and male used this food source, with the male approaching first, followed by the wild females."

After his re-release M2332 began to show signs of adaption to the wild with full integration to his group, foraging for native fruits and hunting for insect prey:

"Following the re-release of the male, we accompanied the animals more closely (5-
10 m) and were also able to observe the male foraging for animal prey composed mainly of insects. He did not have any difficulty moving in the forest canopy."

"We followed the group daily for one month, supplementing food twice a day. During the next two months we collected systematic data and reduced the food supplementation to once a day. During these three months, the male did not leave the females, and began feeding on native fruits (Myrtaceae)."

The death of M2332 and lessons learned in reintroduction

However, sadly in spite of showing some signs of adaption to the wild and success in reintroduction M2332 was unfortunately found the victim of predation by an ocelot :

"Despite increasing progress in the reintroduction process, sadly, the male was found dead early in the morning on 30 November 1999. He was on the ground, with the chest cavity opened and without hands. The animal was not in rigor mortis, and the body temperature was normal, so we assume that the predation had occurred shortly prior to our arrival. He still had a collar. The females were in the canopy, above the dead animal. Based on these observations we concluded that the animal was possibly killed by an ocelot Leopardus pardalis, a common feline in MDSP."

Nevertheless, critical lessons had been learned in the reintroduction attempt that could be applied to future actions and the operation was deemed to be a partial success for the following reasons:

"In our case, the skills of the reintroduced male enabled him to move at high speed and orient through the canopy, often out of sight of the females. This would probably not have been possible with out his two years of free-ranging experience at Jersey."

"Reintroduction using a mix of wild and captive animals seems to be a useful strategy for the conservation of the black lion tamarin. In this first reintroduction the wild animals worked as guides for the captive individuals, indicating the routes inside the forest and novel food items. We assume that this first reintroduction had partial success as the mixed group was very bonded and the captive animal could move and feed freely in the wild. Neverthe less, more such reintroductions are needed to evaluate better the efficacy of this manage ment tool for black lion tamarin conservation."


Photo credits to @Maguari and @Giant Eland.

Source: "Preliminary evaluation of the reintroduction of a mixed wild captive group of black lion tamarins Leontopithecus chrysopygus", CLAUDIO VALLADARES-PADUA et al, 2000 (Journal: The Dodo).

 

The arrival of the Mauritius Kestrel at Jersey zoo (1990)



1990 also marked the arrival of a critically endangered species at Jersey zoo that @Carl Jones of the Jersey Wildlife Preservation Trust (today known as the Durrell Trust) had been instrumental in conserving within its native range, the Mauritius kestrel.

This move was inspired by the success that had occurred with the ex-situ captive breeding of the species in Mauritius :

"The Mauritius kestrel provides an outstanding example of how well an acutely engered species can respond to intensive, hands-on management when it is carried out in a co-operative and scientific manner. The fact that the captive-reared and released kestrels are so plastic in their ecological and behavioural adjustments to modified habitats on Mauritius adds an encouraging dimension to the probability for a viable, long-term recovery of the species (Cade, 1986)."

Two breeding pairs of captive bred kestrel arrived at the Jersey zoo that year from the Black River Government aviary facility in Mauritius.

The hope behind their arrival was that these raptors would form part of a captive breeding population that would eventually involve several other zoos in the British isles.

Photo credit to @gentle lemur.

Sources: "A SUMMARY OF THE CONSERVATION MANAGEMENT OF THE MAURITIUS KESTREL Falco punctatus 1973–1991", Carl Jones et al, 1991 (Journal: The Dodo).

 

Housing the Mauritius Kestrel (1990-1999)



The first Jersey kestrels consisted of both an older and younger pair of birds. After quarantine each pair were housed in spacious flight cages that had been purpose built for them.

These outdoor aviaries were well planted and furnished with several dead branches and tree trunks for the kestrels to use for perching.

"The outside flights measured 6.40 x 4.3 m with a height varying between 3.2 and 3.7 m for one, and 3.7 and 4.6 m for the other. Perching was provided with branches of various dimensions and upright tree trunks. Some large boulders were also placed in each aviary. The ground was covered with a substrate of sand and grass and a variety of plants were provided, e.g. honeysuckle, Lonicera japonica, Russian vine, Polygonum baldschuanicum and Cordyline australis. Access to an indoor heated area measuring 1.8 x 3.7 m is via two popholes 173 cm above ground level."

A specially designed indoor quarters for the kestrels was also provided:

"Access to an indoor heated area measuring 1.8 x 3.7 m is via two popholes 173 cm above ground level. Once indoors, this area can be divided into two sections should the need arise (e.g. temporary separation of the younger pair of kestrels). Heating is provided all year round by a covered bar wall heater, and a 100 W Salamander infra red spotlight (under which the birds can perch) which gives a constant minimum temperature indoors of 65 °F /18.3 °C. A nestbox provided for the breeding season is used throughout the year as a resting place. A thin layer of sand covers the floor."

A seasonal routine for the birds was established:

"Both pairs of kestrels were kept together throughout the year, although initially there were some management problems with the younger pair. The female assumed a very aggressive dominant role, chasing the male relentlessly, so that temporary separation was necessary. Five primaries trimmed on the female's left wing rectified the problem. At the onset of the breeding season and until early winter the kestrels have permanent outside access. However, during the winter months (November - March) all the birds are shut inside at 1500 hours when they are fed. This still allows sufficient daylight hours for feeding. Temporary adjustment of this routine was necessary once the two young kestrels had fledged. To avoid any potentially harmful harassment from the adult birds constant outside access was given."

The birds were fed a carefully formulated diet:

"The kestrels are fed on three small dead white mice Mus musculus (or occasionally small weaner rats Rattus norvegicus) once daily. Additional food is available during the breeding season and during exceptionally cold spells of weather. A pinch of vionate powder, a multi-vitamin supplement, is used once weekly. Any mice surplus to requirement are cached and, when located, these are removed to prevent possibly long periods ofstorage and subsequent retrieval by the kestrels to consume."

Nestboxes were provided in anticipation of breeding:

"The kestrels were provided with nestboxes well in advance of the breeding season. Each pair had one box (placed indoors) measuring 61 x 25 x 25.5 cm and was positioned in a corner 250 cm above floor level, with the entrance facing towards a pophole providing outside access. The nestbox was divided into two sections by a shallow 5 cm sill. The rear half contained an inspection door and was intended as the nesting area. A substrate of small disinfected gravel was used throughout."


Photo credit to @Writhed Hornbill and @molinea (Photos of kestrel taken at Chester Zoo).

Source: "FIRST BREEDING IN EUROPE OF THE MAURITIUS KESTREL AT JERSEY WILDLIFE PRESERVATION TRUST", Hilary J. French, 1992 (The Avicultural Magazine).

 

Captive breeding of the Mauritius Kestrel (1991)



Within a short period of their arrival the Jersey kestrel pairs had already begun to show courtship behaviour and signs that breeding would soon take place:

"In Jersey, the breeding season for the kestrels appears to start in March, with the first aerial displays witnessed in this month. (In Mauritius the breeding season extends from September - March, Jones et al, 1991)."

The older pair as experienced breeders encountered no problems, however, the younger pair were inexperienced:

"Prior to egg laying, and throughout this period, both female kestrels needed to reach and maintain peak body condition. Courtship feeding by the male was vital to ensure this. In the older pair of kestrels this role was already well established with regular feeding of the female by the male. With the younger pair in their first season, initially the female snatched food from her mate who was reluctant to surrender his prey. However, as time progressed, very gentle beak to beak food passing from male to female occurred, both whilst the female was laying and then incubating, and during the early stages of chick rearing."

Breeding was observed in the pairs and the nestboxes were routinely checked for signs of eggs :

"Consequently from late April, with the first copulations observed, the nestboxes of both pairs were checked daily. Initially this was for signs of a "scrape" or depression in the gravel, upon which eggs would be laid.

Soon both females had laid a clutch of eggs :

"Mauritius Kestrels normally lay a clutch of three or four eggs (Jones et al, 1991). However, the young female laid a clutch of five eggs which is unusual. Of these, three were fertile (one of which subsequently died as a mid period embryo), and two were badly cracked and dented. The older female laid two clutches, the first consisting of two eggs and the second of three eggs. Both clutches were infertile."

A plan was put in place by the keepers to intervene and artificially incubate the viable eggs to ensure their hatchability:

"It was intended that clutches of eggs laid by either pair of kestrels would remain with the female for approximately ten days natural incubation. It has been proven in falcon species that this greatly improves hatchability (Burnham, 1983). After this clutches would be removed to complete incubation artificially, and after hatching an initial period of hand rearing, chicks would be returned to the kestrels to fledge."

The eggs soon hatched :

"Two eggs hatched (17.6.91 and 23.6.91) after an approximate incubation period of 31 and 33 - 34 days. This can only be estimated, since after laying three eggs and appearing to have started full incubation, the young female laid a further two eggs of which the exact date of lay is unknown. The second smaller chick (23.6.91) took approximately seventy-seven hours and thirty minutes from chipping to drying after hatching, compared to approxi¬ mately twenty four hours for its sibling."


The young kestrels

The handrearing of the hatchlings now commenced:

"Both chicks were given their first feed no later than five hours after hatching (Jones, 1984). The internal organs of white mice, Mus musculus were used (excluding intesti¬ nal tract) moistened in cooled boiled water. Food was offered with tweezers, five times per day initially (0700, 1100, 1430, 1730 and 2200 hrs.) with an eight hour gap overnight."

The diet of the hatchlings was carefully monitored:

"By days three and four, very finely chopped skinned mouse flesh was fed (still excluding the intestinal tract) and, at seven days, small quantities of mouse fur were added. As rearing progressed, the pieces of food offered were gradually increased in size and the chicks were able to snatch food from the tweezers as their coordination improved. Day old chicks were occasionally used (from day 3) during rearing. The young kestrels were weighed before and after every feed during hand rearing."

Before long the young kestrels were ready to be reintroduced back to the adult birds:

"In view of the inexperience of the younger pair of kestrels and the availability of an excellent pair for foster rearing, only the older chick was returned to its natural parents, whilst the younger chick was fostered. The two chicks had received twelve and thirteen days of hand-rearing each, and weighed 51.5 g and 61.1 g respectively. Both chicks were placed in their nest boxes and dummy eggs removed at no later than 0930 hrs."

This went well and the adults commenced to care for the nestlings:

Fortunately on returning to their nestboxes, after dummy eggs had been exchanged for chicks, both females immediately assumed protective roles brooding their young, whilst the males promptly delivered mice from the food platform. Later each female could be heard breaking up mice into pieces to feed to an extremely vocal chick.

Fledging from the nestboxes was later thankfully successful for both chicks:

"The young kestrels fledged at 37 and 38 days old, spending the majority of time at the front of the nestbox for several days prior to this. Initially both fledglings continued to be fed by the adults, even though one was observed feeding independently four days after leaving the nestbox."

The kestrels were eventually removed from the adults and went to occupy their own aviaries at the zoo:

"Both kestrels remained with the adults until 210 and 204 days old respectively, before being removed from their aviaries. Separation was slightly earlier than anticipated due to some chasing of each of the young kestrels by the adult pairs."

The Jersey born Mauritius kestrels were deeply significant animals for the budding captive breeding programe as they represented the first successful captive breeding of the species in a European zoo:

"The establishment of breeding pairs of Mauritius Kestrels at Jersey Wildlife Preservation Trust and in the future at other collections in the British Isles or elsewhere will provide a useful reservoir of birds outside Mauritius."

Photo credit to @Writhedhornbill.

Source: "FIRST BREEDING IN EUROPE OF THE MAURITIUS KESTREL AT JERSEY WILDLIFE PRESERVATION TRUST", Hilary J. French, 1992 (The Avicultural Magazine).

 

Wrap up of the Black lion tamarin species conservation at Jersey zoo


Over the past twenty years the black lion tamarin has sadly died out in every zoo collection outside of Brazil but Jersey zoo who continue to keep the species:

"The animals kept at Jersey Zoo successfully produced offspring, and some L. chrysopygus were transferred to other institutions in Europe, North America and Australia. However, the majority of these individuals died, and nowadays there are only extant captive BLT overseas in Jersey."

By the year 2015 it had become clear that even the Jersey population could be in danger of dying out and so an import of fresh tamarins from Brazil was needed.

In 2017 five individuals from the São Paulo zoo colony were sent to Jersey to bring new blood and genes into the group and to keep the species going at the zoo. This led to the birth of two young black lion tamarins in 2018 which were the first to be born outside of Brazil since 2011.

As of 2020 of the fifty five black lion tamarins that are currently held in captivity worldwide Jersey hold eight of these animals while the rest are held by zoos and captive breeding centres in Brazil. The Jersey BLT group remain the most genetically distinct of all of the captive populations and so are a critically important component of the ex-situ effort to conserve the species.

Jersey zoo and the Durrell Trust continue to heavily support the ex-situ and in-situ conservation of the species within Brazil.

Photo credit to @Rick J.

Source: "Studbook and molecular analyses for the endangered black-lion-tamarin; an integrative approach for assessing genetic diversity and driving management in captivity", Paola Andrea Ayala Burbano et al, 2020 (Journal: Scientific reports).

 

Black lion tamarin videos from Jersey zoo:

BLT being weighed:


BLT birth in 2011:



The in-situ work of my colleague Gabi Rezende and her time at DESMAN:

 

Arrival of the blue crowned laughing thrush at Jersey zoo (1997)


In 1997 a critically endangered endemic Chinese species arrived at Jersey zoo but this wasn't of the black and white furry variety but of the feathered blue variety, the blue crowned laughing thrush.

At that time this striking species was thought to merely be a subspecies of the yellow throated laughing thrush.

As such, nothing much was known about either the wild ecology or the husbandry requirements of this beautiful passerine in captivity.

Photo credit to @SMR (Photo taken at Chester zoo).

 

The blue crowned laughing thrush (1997 to the present)



Housing the blue crowned laughing thrush



The Jersey blue crowned laughing thrushes have been housed since the late 1990's in lushly planted aviary style enclosures.

The species has been kept in varied groupings including both single species and mixed-species but the birds are always kept in pairs to avoid intraspecific agonistic behaviour:

"BCLTs at Jersey Zoo have been housed in a variety of aviaries with outside access in pairs, single-species groups and mixed-species groups. Aviaries were 2–6 m wide by 2.5–9 m long and 2–3 m high, with a sand substrate, containing natural vegetation."



During the mid to late 2000's some of these birds were also kept in the "Jewels of the forest" walkthrough and mixed-species exhibit for some time:


Breeding challenges (1997 -2000)


The blue crowned laughing thrush initially proved to be a very difficult bird to breed at Jersey due to its nervous and highly-strung nature and it took four years before the species showed any signs of engaging in breeding behaviour.

In 2000 the staff managed to stimulate nesting behaviour promoting breeding behaviour which led to eggs being laid and a single chick hatching in 2001. In 2002 breeding occurred once more at Jersey and this lead to five thrushes being hatched and handreared by keepers.

From subspecies to species status (2000 - 2018)


Throughout the 2000's the status of the blue crowned laughing thrush was unclear and it was variously considered to be either the monotypic species (Garrulax courtousi) or to be two subspecies of the yellow throated laughing thrush.

However, evidence began to accumulate that pointed towards the blue crowned laughing thrush being a distinct species and this was further confirmed by a rigorous phylogenetic study in 2018.

Other peristent challenges (1997 to the present)

Maintaining the health of blue crowned laughing thrushes held at Jersey zoo has been a steep challenge at times and a recent study revealed that approximately 22% of mortality of these birds at the zoo has been due to infection by protozoan coccidian parasites.

"BCLTs have been kept at Jersey Zoo from 1997 to the present; systemic Isospora infections are the most common cause of mortality in BCLTs at the zoo (Barbon et al. 2013). Isospora species causing systemic infections, previously described as atoxoplasma (Barta et al. 2005; Upton et al. 2001)."

Improvements in husbandry and veterinary treatment generated through research is an ongoing priority in the zoo to mitigate future mortality of these precious birds.

Wrap up of the future of species conservation at Jersey



Sixteen blue-crowned laughing thrushes are currently maintained in the aviaries of the Jersey zoo.

Important work to breed these individuals and collaborate with the management of the ex-situ population of this threatened species is ongoing and continues in earnest.


Photo credits to @Dylan, @JerseyLotte , @Bwassa, @KevinB and @ro6ca66 (Last three pictures of birds taken at Chester, Antwerp and Waddesdon manor).

Sources: - "Clinical and Pathological Aspects of Systemic Isospora Infection in Blue-crowned Laughing Thrushes (Garrulax courtoisi) at Jersey Zoo", Alberto Rodriguez Barbon et al, 2017 (Journal: The Solitaire).
- Blue-crowned laughing thrush | Durrell Wildlife Conservation Trust.

 

I don't believe that it is true about GHLT at Adelaide Zoo. They were able to enter into the BLT program due to the success of breeding GLTs. Have you any reference for GHLTs at Adelaide? Only other similar tamarin which might be confused with were the red-handeds but they were only at Perth, with some animals being moved to Whyalla (I think). Pretty sure none ever made it to Adelaide.