TAN CHENG LI The Star 2 Jun 14;
Mistakes of the past have cost us many rhinos. Now’s the time to learn from the errors.
Between 1984 and 1995, a total of 22 Sumatran rhinos were captured in Peninsular Malaysia and Sabah for a captive breeding project. Except for one which was already pregnant when captured, none bred while in captivity, and all have since died.
Today, there are three captive rhinos in Sabah, taken from the wild in recent years – a male in 2008 and two females in 2011 and in 2014. They are our last hope to breed the critically endangered species in a final bid to boost their numbers.
In the wild, exact numbers are unknown, but rhino experts say the species is most likely extinct in Peninsular Malaysia and on the verge of extinction in Sabah, which has fewer than 10. In short, the Sumatran rhino is “functionally extinct” in Borneo and in Malaysia – meaning that the few individuals remaining are insufficient to save the species.
How did we reach this dire state? A paper “Preventing the extinction of the Sumatran rhinoceros” by three experts from the Borneo Rhino Alliance (Bora) gives a critical account of how Malaysia blundered in its attempt to wrest the species from the brink of extinction.
It points to a combination of lack of knowledge on rhino reproduction biology, poor husbandry and veterinary care in captive centres, a misguided approach in focusing on protecting rhinos in the wild, and lack of co-operation between rhino range states that led to today’s rhino crisis. The paper was authored by Bora chairman Dr Abdul Hamid Ahmad, executive director Dr Junaidi Payne and veterinarian Dr Zainal Zahari Zainuddin,
“There is finally a realisation in Malaysia that it muddled through with Sumatran rhinoceros in the past 50 years, recycling fabricated population estimates and refraining from making necessary conservation decisions,” states the authors in the paper published in the Journal Of Indonesian Natural History (December 2013). It also publicly reveals for the first time, information on the causes of deaths of captive rhinos.
Hunted out
Rhino horns have long been favoured as a folk remedy. In the first decades of the 20th century, extensive hunting had already led to a precipitous decline in its distribution and numbers. By the mid-20th century, the species was depleted from its former range and in danger of extinction in Malaya and Borneo and elsewhere on mainland Asia.
By the early 1980s, wildlife experts estimated the Malaysian population at between 52 and 75, including 20 to 25 individuals in the Endau-Rompin area in Johor, and 15 to 30 in Sabah. In 1995, Dr Zainal found evidence of only five adult rhinos in Endau-Rompin, showing that published estimates of rhino numbers were notoriously unreliable, and that actual numbers had declined by half over the preceding decade.
The United Nations-led Sumatran Rhinoceros Conservation Strategy project (1995–1998) also pointed to a dwindling population, but “... inflated numbers kept appearing in public domain, largely due to some proponents’ disbelief that two decades of effort had failed.” As recent as 2007, official figures still put the rhino population at 70 to 100 in Peninsular Malaysia and 30 in Sabah. The far-from-accurate population figures could have jeopardised conservation efforts.
After the plight of the Sumatran rhino surfaced in the early 1980s, the International Union for Conservation of Nature in 1984 convened the first Sumatran Rhino Crisis Summit, in Singapore. Some 20 representatives from governments, zoos and wildlife institutions made plans to prevent the species’ extinction, which included enhanced protection of wild rhino populations, raising awareness, and developing a global captive breeding population.
From 1984 to 1995, 22 Sumatran rhinos were captured in Malaysia (see table) for a breeding programme. At that time, nothing was known of rhino reproductive biology. The paper says an analysis reveals several kinds of failures which should not have been allowed to occur with such a precious, critically endangered species.
Many rhinos were kept in conditions which caused them poor health and stress. It was known that rhinos live in closed-canopy forest and typically wallow in clean mud for five to six hours daily. However, most captive rhinos were kept in conditions of exposure to sunlight and in some cases without access to clean mud wallows. Frequent sunlit conditions have been linked to partial and complete blindness in some captive rhinos. Other mistakes included feeding unsuitable milk to an infant rhino and unsuitable enclosures which caused one rhino to be trapped between bars, and asphyxiate.
Deaths at rhino centres
Most shocking of all, basic hygiene was generally poor. Some rhinos were kept for long periods in facilities that lacked basic hygiene protocols and biosecurity measures, leading to bacterial infections and eventually, deaths. There was also a lack of experienced veterinary care, causing identification and treatment of disease to come late or not at all. Prior to the development of the Sungai Dusun Rhino Conservation Centre in Selangor, rhinos were maintained at Melaka Zoo, where treated piped water was installed only after the deaths of Sri Delima and Julia.
The tragic death of all six rhinos at Sungai Dusun between April and November 2003 put an end to the captive breeding effort. The cause of deaths was reported to be due to trypanosomiasis originating from buffaloes on nearby land. The paper disputes this. It says long-term monthly monitoring of blood for parasites and blood parameters showed no trypanosomes (a parasitic protozoa) in the rhinos. Also, no trypanosome infection was detected in the blood of the buffaloes. In the post-mortem, trypanosomes were detected in only two of the seven rhinos that died, while abundant bacterial growth was found in the vital organs; mucoid Escherichia coli in five animals and Klebsiella pneumoniae in four.
The paper states that the death of male rhino Shah in January 2002 from mucoid E. coli should have prompted the facility to be on strict alert. Sensitivity tests were done in 2002 and gentamycin was found to be the only effective treatment but it was not used on the ill animals. (The tragedy recurred seven years later – from Sept 17-29, 2010, seven Malayan tapirs died from mucoid E. coli at Sungai Dusun, which by then had been turned into a tapir breeding centre. Only one tapir showed trypanosomes in the blood.)
The paper says trypanosomes might have infected the rhinos and tapirs at any time at Sungai Dusun, and that natural resistance effectively suppressed their growth until the advent of poor health and compromised immune response resulting from chronic mucoid E. coli and Klebsiella infection.
“The conclusion that trypanosomes were the cause of the Sungai Dusun deaths may have been reached erroneously, in order to allow parties involved to avoid responsibility for chronic poor hygiene in the facilities,” says the paper.
It sums up the reasons for the failure of the 1984-1995 effort on captive breeding:
> Insufficient knowledge of Sumatran rhino breeding biology and inadequate high-quality veterinary care and husbandry in captive facilities.
> Unsuitable diet in some facilities, with insufficient attention paid to the risk of iron ferritin disease.
> Stress on rhinos due to weaknesses in facilities design and poor visitor control.
> Over half of all female rhinos have reproductive tract pathology, making natural breeding difficult or impossible.
> Absence of suitable males in Peninsular Malaysia; males in Sabah with low or no sperm production.
> Rhinos were not shared between Peninsular Malaysia and Sabah due to beliefs that they were different subspecies, and between Peninsular Malaysia and Indonesia due to loss of trust after the initial exchange.
> Rhinos were not sent to the United States for breeding programmes.
> Some pairings involved inexperienced or incompatible rhinos.
> Artificial insemination was never attempted due to lack of knowledge.
Failure in preserving wild rhinos
With the deaths of the captive rhinos, the breeding project became unpopular and the focus shifted to saving rhinos in the wild rather than bringing them into fenced, managed conditions. This proved to be a misguided approach as according to the paper, no one knows for sure whether wild populations are of sufficient size and fecundity to assure their survival, even in the absence of poaching.
Moreover, this approach does not address the impact of various factors on small, isolated wild populations or the Allee effect, which refers to a “positive correlation between population size or density and the mean individual fitness”. The Allee effect states that when a population declines to very low numbers, breeding success declines in tandem. This is because factors associated with low numbers (difficulty in finding a mate, narrow genetic base, skewed sex ratio, reproductive tract pathology linked to long periods without breeding) contribute to drive rhino numbers lower and lower, even in places with suitable habitat and no hunting.
“In small, scattered and non-contiguous populations, it is just a matter of time before the average annual death rate exceeds the annual birth rate, and before the population goes extinct.” The authors of the paper believe that the Allee effect was significantly impacting survival of wild rhinos because:
> All records of wild juveniles were anecdotal, with no information on actual annual increase (or decrease) in wild population size.
> Rhino numbers have been very low for many decades in most if not all areas where they are still present, so inbreeding was likely.
> A skewed sex ratio was observed during the capture of rhinos from 1984 to 1995. The male to female ratio was 1:9 in Peninsular Malaysia and 8:1 in Sabah, and all the captured males were old.
> Reproductive tract pathology is common in the captured females, a phenomenon associated with lack of either breeding or carrying of foetuses to successful birth.
“The Allee effect has likely been present in all Sumatran rhino populations over an extended period, effectively entering the Sumatran rhino into the extinction vortex irrespective of whatever protective measures might be put in place in the wild,” declares the paper.
The lesson from Malaysia, it says, is that the priority should have been to increase the number of rhino pregnancies rather than to hope that the mortality rate of wild rhinos through poaching could be reduced. “Protecting wild rhinos may be an over-ambitious option and captive breeding may have a greater chance of success than prevailing wisdom admits.”
What now?
Last April, 100 wildlife experts convened the second Sumatran Rhino Crisis Summit in Singapore. They concluded that without immediate and committed conservation intervention, the Sumatran rhino will go extinct soon. Indonesia and Malaysia were urged to collaborate.
Simulations done during the summit showed that the species stands a good chance of surviving if there are at least 30 individuals with a birth interval of three years or less. The future of populations smaller than that is bleak even if they are healthy and protected. Using a more realistic birth interval of seven years, a starting population of 50 rhinos will have a negative growth rate of about -3% per year.
“This means that, without intervention, all possible known wild and captive populations are in an extinction vortex and are not sufficiently abundant to increase populations in isolation of each other.”
The paper says to reduce the current captive population’s extinction probability to below 10%, some 16 rhinos need to be transferred into captivity and managed with an interval of three years.
To date, there have been only four captive births, all descendants from the same pair in Cincinnati Zoo, the United States. The Sumatra-caught rhinos, Emi and Ipuh, both fertile and compatible, had received excellent care there, resulting in rhino births in 2001, 2004 and 2007. Their offspring, Andalas, was sent to the Sumatran Rhino Sanctuary in Way Kambas National Park, Sumatra, in 2007 and five years later, fathered a male calf.
Lesson learned
“Much of the fear over captive breeding stems from past failures,” says the paper. “But knowledge on rhino biology, animal husbandry and reproductive technology has improved.” Advances include the cryo-preservation of egg cells by vitrification, successful artificial insemination and subsequent live births of the white and Indian rhinos, and in vitro fertilisation.
The paper points to a general consensus that the sole imperative now is to produce Sumatran rhino embryos. This can only be done by bringing every rhino into closely managed facilities, and making maximum use of their gametes.
“Having these rhinos and gametes as part of a globally managed meta-population (separated populations, but with some interaction) is essential, and attempts at natural breeding and artificial insemination must continue as long as either is possible.”
The paper states that in the absence of agreement to share rhinos and gametes between nations and facilities, the current scope in Malaysia is limited. Thus, a key element of current effort is the cryo-preservation of gametes and cells that might be used in the future to restore the species after its extinction in Malaysia.
Raising hope for baby rhinos
LIM CHIA YING The Star 2 Jun 14;
Last-ditch effort: Advanced reproductive technology offers hope for the Sumatran rhino's survival.
Lying chest-down in a quiet, dignified manner, Iman slowly shuts her eyes. She’s taking a rest, says her caretaker, but cutting a forlorn figure, it’s possible that she is trying to contain the discomfort from the pain inside her. A bunch of tumours are growing inside the female rhino’s womb, causing her to bleed.
Some 20 minutes later, she awakens and inches her way to the front of her enclosure to get her feed of leaves and fruits. She appears to have forgotten her pain, and happily gnaws at her food.
Here at the Borneo Rhino Sanctuary (BRS) located in Tabin Wildlife Reserve near Sabah’s east coast town of Lahad Datu, I watch Iman going about her daily routine with a mixture of delight and heartbreak – delight in noting that she continues to eat like a healthy rhino, and heartbreak from the fact that she may never recover from the ailment she has been inflicted with.
The sanctuary is what she calls home now, together with two other rhinos, a male called Tam and a female named Puntung. All were captured from the wild and transferred to the sanctuary where proper care is rendered to ensure their well-being and survival.
The Sumatran rhino is critically endangered; some would say they are on the verge of extinction. Less than 100 are believed to exist in Borneo (Sabah in Malaysia and East Kalimantan in Indonesia) and Sumatra.
Since 2009, Yayasan Sime Darby has put in RM11.4mil for operational expenses and running of the BRS programme. The facility was built by the Sabah Wildlife Department while non-governmental organisation Borneo Rhino Alliance (Bora), led by its executive director Datuk Dr John Payne and veterinarian Dr Zainal Zahari Zainuddin, manages the husbandry and breeding efforts.
Much excitement abounded when Iman was captured on March 10 in one of two traps laid out for her in the Danum Valley Conservation Area. Hopes were high that she would conceive and bear babies, but that soon dissipated after she was found with eight non-malignant tumours in her reproductive tract. In Puntung, her uterus has cysts, making it impossible for her to become pregnant or sustain an embryo.
Iman is being treated to flush out pus as well as halt blood loss and further enlargement of her tumours. Payne reckons that her condition is under control, though the tumours can drain her energy.
“It’s unfortunate that female rhinos have a tendency of being infected by tumours and cysts if they do not produce babies once becoming sexually mature,” he says. “In the case of Puntung, it’s likely that she suffered a failed pregnancy in the past while Iman’s condition implies that she had been sick for a long time.
“Both may be young but their reproductive defects mean it’s highly unlikely they can breed naturally. Our best bet now is to harvest their eggs and sperm from our mature bull Tam for in-vitro fertilisation attempts later on. Now is the time for us to keep trying. There’s no giving up on this final salvation with our last batch of Sumatran rhinos.”
He says Bora has embarked on advanced reproductive biotechnology in partnership with the Leibniz Institute for Zoo and Wildlife Research (IZW) in Berlin, Germany.
“We are engaging IZW to assist us with lab breeding of the embryos as the institute specialises in reproductive problems of mammals in captivity. On May 9, we had IZW’s Dr Thomas Hildebrandt and his veterinary team in Malaysia to remove two oocytes (immature egg cells) from Iman. They are stored in a buffer solution at rhino body temperature, as the idea is to mature them in the lab.
“I’m cautiously optimistic of mixing the oocytes and sperm, which can be done either through in-vitro fertilisation if there are plenty of sperms, or the intracellular sperm injection technique, which is to inject single, individual sperms into the egg,” says Payne.
IZW has had success with in-vitro fertilisation with the black rhinoceros, though the fetus died eventually. While such fertilisation attempts have yet to be tried on critically endangered species, Payne says the method has been successful with the European bison (numbers at one point were down to 50 before they were captive-bred and saved from extinction in the 1920s and 30s) and the Arabian oryx (numbers rebounded following release of captive-bred animals into the wild from the 60s to 80s.)
“It will be good for the Malaysian government to be made aware that advanced reproductive biotechnology is the way forward to produce baby rhinos to ensure the species’ continuity through generations to come. When a species becomes scarce, the only option is to keep them in captivity and carry out breeding, assisted or otherwise,” says Payne.
He says the technique includes preserving rhino genomes through the freezing of cells.
“We are also looking to synchronise the oestrous cycle (period of sexual receptivity) of Puntung and Iman through use of hormones so that both can produce eggs on a date that can be predicted. This is done to enable more extraction of oocytes when the IZW team return to harvest the second batch.”
Tam will contribute his sperm in more frequent sessions of the electro-ejaculation procedure, regarded as a safe collection of semen samples performed under general anaesthesia.
Payne says if the assisted reproductive attempts succeed, the next step is to seek surrogate rhino mothers for the embryos to grow.
“We have the option of either using two the fertile female rhinos in captivity in Indonesia, or other rhino species available in zoos, which would be the last resort.
“There have been interactions between the Malaysian and Indonesian governments, and we are open to any moves from Indonesia to collaborate. I think it is fair to say that Indonesia, though having few Sumatran rhinos themselves but a lot more than us, will play the key nation role to save the species from extinction,” he says.
The Sumatran Rhino Crisis Summit held in Singapore last April had acknowledged the importance of an alliance and had proposed for governmental collaboration.
Payne says he wishes to clarify the general perception that Sumatran rhinos are dying out from problems related to deforestation, habitat loss and poaching – factors which he says are not true.
“Their deaths have nothing to do too with the oil palm industry, that’s just a misguided (perception). Rather, it is more linked to the biology of the species. It must be said that even during the 1930s, Sumatran rhinos were already very rare,” he says.
Giving a low-down on the animal’s ancient existence, he says the Sumatran rhino, the world’s smallest rhino, is a prehistoric relic dating back 20 million years when they roamed the lowlands. They survived and evolved along the different periods when other species were wiped out, and until about 1,000 years ago, the Sumatran rhino was hunted for its horn after it was widely presumed to contain anti-inflammatory and cooling properties. This depressed the population size from a long time ago, says Payne.
The Sabah government had, last March, decided to trap all remaining wild rhinos rather than leave them in the forest where chances of meeting a mate and breeding are low.
“This is why we will continue looking rigorously for more wild rhinos and the focus is on Danum Valley this year, where we believe there are still a few more out there,” says Payne.
Yayasan Sime Darby chief executive officer Yatela Zainal Abidin says a new facility will be ready in Danum Valley in July to house new rhinos caught there. The RM1.4mil centre is funded by Sabah Forestry while Yayasan contributed RM250,000.
“The scenario seems bleak and desperate, but we are not giving up. We are hopeful that the scientific approach can boost birth of babies and save these rhinos from vanishing,” says Yatela.
Yayasan’s commitment to the rhino project spans six years through 2015, after which it will be reviewed for future extensions.
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