Talking Point

Vaccinations are vital for saving Amur tigers

AK Singh

While the world focuses on the development of new vaccines against COVID-19, biologists are building the case for using vaccines for the conservation of wildlife. A research on the impact of canine distemper virus (CDV) in the Russian Far East concludes that vaccination of Amur tigers is a potentially important strategy to avoid extinction of small populations. The biologists initiated their study following the deaths of several Amur tigers infected with CDV in the Russian Far East in 2003 and 2010. This region supports two populations of tigers, including one of the largest in the world with some 500 individuals in the Sikhote-Alin Mountains.

Historically, wildlife biologists paid little attention to the impact of diseases on wildlife populations. Pathogens and parasites were regarded as a natural part of the ecosystem, which had evolved to co-exist with their wildlife hosts. Large outbreaks were infrequent and it seemed that there was little that could be done to alter their outcome, so they were simply left to run their course. While that approach still holds today, the world and the threat posed by disease have changed. Once, large wildlife populations existed across vast landscapes in numbers of sufficient size to survive disease outbreaks. Today more species are relegated to small islands of habitat that support fewer individuals. In some cases, an outbreak could be the “straw that breaks the camel’s back,” driving these small populations to extinction locally.

The tiger is a classic example of this predicament. Once widely distributed across Asia, tigers are now mostly confined to protected areas and surrounding buffer zones. Even in the tiger’s Indian heartland one study projected that even under favorable scenarios, the majority of protected areas will soon support an average of just 14 individuals. Samples collected from Amur tigers including Boris and Svetlaya enabled researchers to assess the population’s exposure to canine distemper virus. Only a few protected area networks have the capacity to hold larger, more stable populations. Under such conditions, each of these small populations is vulnerable to a host of unpredictable events, making a disease outbreak a serious threat. The other, much smaller population straddles the border of Russia and China and numbers perhaps 30 individuals (most in the SW corner of Primorski Province, Russia), but is particularly important as a source for recolonizing northeast China. Tigers with CDV have died in both populations. The recent study showed while the risk that CDV posed to the large Sikhote-Alin population was extremely low, in a small population like the one in Southwest Primorski, CDV increased the likelihood of local extinction within 50 years by 65 percent. Even robust tiger populations do not exist at sufficient numbers or density to allow a pathogen like CDV to persist in an ecosystem. Usually, there is another more abundant reservoir host species (or multiple species) that allows a pathogen to persist and act as a continual source of infection for rare hosts like tigers.

It is often assumed that domestic dogs are the main reservoir for CDV outbreaks in wildlife. A 1994 CDV outbreak in Serengeti lions began with a spillover from local dogs. A dog vaccination program helped contain future outbreaks. In Russia, the research demonstrated that dogs were not the reservoir in the local ecosystem. Rather, small carnivores like sable, badgers, and raccoon dogs were passing the virus to the tigers. Since there is currently no oral bait-based vaccination for CDV, it is not feasible to control transmission in those species. Vaccination of tigers themselves is the only option. Fortunately, existing injectable vaccines are safe and effective in tigers. The simulations indicate that even vaccinating a small proportion of the Southwest Primorski tigers (e.g. 2 animals per year) would significantly reduce the probability of population collapse. This low coverage vaccination strategy is not intended to achieve “herd immunity” (the objective of COVID-19 vaccinations) but is simply an “insurance scheme” that allows an immune group of tigers to survive future outbreaks and enable population recovery.

The 2018 outbreak of CDV in the only remaining Asian lions should serve as a warning that other big cat populations are also likely at risk. Priority should be given to identifying tiger populations like those in Southwest Primorski with high strategic value despite their small size. Research to identify local CDV reservoirs can inform control strategies before outbreaks occur.  Proactive programs to vaccinate tigers in the wild should only be considered for high-risk and high-value populations where epidemiological research indicates that it is necessary. However, there are a surprising number of tigers that are being captured each year across Asia for research, for dealing with human-tiger conflicts, and for rehabilitation of injured adults or abandoned cubs. In these circumstances, we recommend that delivery of CDV vaccines be incorporated as a routine part of tiger handling protocols.

Newly developed vaccines hold out the exciting promise of reducing the threat of COVID-19 in human populations. Similarly, if a simple injection of a vaccine known to be safe can likely increase the odds of a tiger population surviving a distemper outbreak, it is incumbent upon science-based conservation agencies to consider adopting this approach.

Indonesia’s plantation program on collision course 

The survival of critically endangered wildlife like Sumatran orangutans and tigers and the livelihoods of Indigenous communities might be in jeopardy as the Indonesian government plans to establish large-scale agricultural plantations overlapping with their forests, activists warn. Under the so-called food estate program to boost domestic production, the government plans to establish millions of hectares of new farmland, mostly for rice and other staple crops. Among the regions targeted by the program is North Sumatra province, home to a number of conservation areas teeming with wildlife species. This past October, President Joko Widodo launched the program in North Sumatra, with a plan to establish 60,000 hectares (148,000 acres) of agricultural fields in four districts. The official map of the food estate program shows at least four conservation areas that fall within the planned plantation sites. They are Subulussalam Forest Park, Siranggas Wildlife Sanctuary, Sikice-Kice Nature Park, and Sijaba Hutaginjang Nature Park.

The map, drawn up by the conservation department at the Ministry of Environment and Forestry, identifies a number of wild animal and plant species that are found in the conservation areas, including tigers, orangutans, pangolins, honey bears, deer, hornbills, pangolins, and orchids. According to the map, the planned food estates overlap with 39% of the region’s known Sumatran tiger habitat and 8% of Sumatran orangutan habitat. Dana Prima Tarigan, the North Sumatra chapter head of the Indonesian Forum for the Environment (Walhi), singled out the Siranggas sanctuary as being particularly vulnerable. It’s home to 16 protected mammal species, including orangutans, with a population density of 0.75 individual orangutans per square kilometer. “Even if the food estate program doesn’t encroach on the Siranggas wildlife sanctuary, there’s still wildlife there,” Dana says. “We found animal footprints there, starting from bears, orangutans, hornbills and tigers. And they are in production forests that will be turned into food estate. So [the animals] are not just passing through, they live there.” The area earmarked for the food estate is still standing forest, but is designated “production forest,” which means it may be cleared at any time for agriculture. “So in the future, conflict between animals and human will be unavoidable because their habitats will be lost to the food estate program,” Dana adds.

The food estate program also poses a threat to Indigenous communities that have long relied on the forests for their livelihood. In the district of Humbang Hasundutan, the program will occupy 280 hectares (690 acres) of land that could potentially impact the village of Pandumaan, according to Delima Silalahi, director of a local NGO called People’s Initiative Development and Study Group (KSPPM). “People only hear that there will be some investors that will manage the food estate,” Delima says. “But it’s unclear what their role will be, and in what portion.” Edismar Nainggolan, the Pandumaan village chief, echoes that uncertainty: “Until now, we don’t know where in our village will become food estate. There hasn’t been anyone who communicated [the program] to us.” Delima said the food estate program could trigger conflicts with Indigenous communities if the land procurement process fails to respect the customary rights of the communities. She attributed this risk to the government’s failure to involve Indigenous communities in the planning process. Dana said Indigenous communities in Fakfak district in West Papua province, another planned site of the food estate program, faced similar fallout. “Even though the status [of the area] is production forest, it’s their forest, with many timber sources that they rely upon,” he says.

Responding to these concerns, Wiratno, the environment ministry’s director-general of conservation, said the mapping of the food estate program area took into consideration the conservation areas and wildlife habitats in order to minimize the impact of the program. “Conservation areas and animal home range have to be avoided,” he says. He adds that the mapping is still in the preliminary stage, with a more detailed survey planned in the future. Luhut Binsar Pandjaitan, the coordinating minister for maritime affairs and investment, says that the food estate program in North Sumatra didn’t overlap with any protected forest areas because it has gone through a series of environmental analyses. “I ensure that it doesn’t cross into the border of protected forest areas or other conservation areas,” he claims. In September, members of parliament called on the environment ministry to conduct a rapid strategic environmental assessment. But Dana from Walhi said such an assessment would likely be rushed and thus not detailed enough to give a good understanding of the potential impact of the food estate program. He added the assessment should have been done long before the government decided to establish food estate in North Sumatra. “That’s what the government always does,” Dana points out. “It is not until there’s criticism that they conduct the KLHS. Ideally it should have been done before the implementation [of the program] and should have been conducted together with the public and stakeholders to conduct mapping and to discuss.”

2020: A good year for Philippine Eagle

Efforts to conserve the critically endangered Philippine eagle, one of the rarest raptors in the world, soared high even amid the COVID-19 pandemic. Despite the global havoc wreaked by the health crisis, the year 2020 ended on a high note for eagle conservationists, with at least two eagle families sighted in the Davao region of the southern Philippine island of Mindanao. The Philippine eagle (Pithecopaga jefferyi) enjoys a special status as the national bird of the Southeast Asian nation, but faces extinction due to hunting and loss of habitat. Growing the population is difficult, as the birds are slow to reproduce. It takes them five to seven years to mature sexually, after which the female lays a single egg every two years.

There are only an estimated 400 nesting pairs of Philippine eagles left in the wild, so the sighting of new eagle families is always a milestone to celebrate for the Philippine Eagle Foundation (PEF), a nonprofit that has worked for more than 30 years in conserving the species. Dennis Joseph Salvador, executive director of the PEF, says he’s optimistic the protection of the Philippine eagle is off to a good start for 2021, given the achievements of 2020, which came despite the debilitating impacts of the COVID-19 pandemic and the threats the birds face daily from human activities such as hunting and illegal logging. “We have demonstrated over the past 30 years our commitment to conserve the mighty Philippine eagle and by hook or by crook, we will sustain that next year and in the years to come,” he says.

Jayson Ibañez, research and conservation director at the PEF, says the organization has for years been searching for eagle nesting sites, particularly in Mindanao, where half of the estimated 400 nesting pairs of Philippine eagles are believed to live. “The recent sightings of two families of Philippine eagles indicate that the forests where they’re seen are still pristine and rich in prey items for the raptors such as macaques, flying lemurs, hornbills, palm civets and snakes, among others,” he adds. Unless disturbed or destroyed by human activities, Philippine eagle nest sites are considered ancient breeding grounds, since generations of eagle pairs will occupy the nest over and over again. “Conserving these core areas of reproduction and keeping the nesting pair and their young safe is pivotal to the success of saving the species from being lost forever,” Ibañez says.

In November, the PEF team, in collaboration with state-run Energy Development Corporation, which runs a geothermal power plant within Mount Apo, launched the “Search for the King of Birds” campaign in the area. The team spent 192 observation hours deep in the forest and emerged victorious after at least eight sightings of nesting pairs of Philippine eagles and their offspring. Ron Taraya, senior biologist and expedition leader at the PEF, told of how he and the team got within 200-300 meters (660-980 feet) of a juvenile Philippine eagle in the wild. The bird exhibited characteristics typical of a 2-year-old of the species: awkward hunting moves, lower flight confidence, and limited flight duration. “It amused us watching the bird take on a group of long-tailed macaques foraging on an escarpment just in front of the waterfalls,” Taraya recalls. The young raptor failed to kill the target macaque, as the group faced off with the bird and grunted threateningly, prompting the eagle to back off and fly into a tree above the ledge.

A few days prior to the close encounter with the juvenile, the team saw a pair of eagles feeding their young one with freshly killed prey following the latter’s “food begging calls.” During the expedition, the team also documented the juvenile’s parents’ aerial rituals that appeared to be a courtship routine. “The two eagles mutually presented their talons in mid-air, called ‘talon presentation,'” Taraya says. “They also did several bouts of flying together in spirals, or ‘mutual soaring.’ Then they flew to different directions; one disappearing inside the deep gorge, while the other landed on an emergent tree. There, the eagle stayed on its perch cleaning its feathers with its beak, called preening. It was also seen scratching, stretching and moving its head. After performing these general maintenance behaviors, the eagle finally flew off and glided beyond the waterfalls until it disappeared behind the tree line.” In Mindanao, September to January is typically nesting season for Philippine eagles, and courtship displays precede each egg-laying event. Eagle pairs at several nest sites across Mindanao start their courtship rituals as early as July, and the routine can persist even after the pair has started rearing a chick. The second sighting of a family of Philippine eagles, in early December, was in the town of Lupon, in the province of Davao Oriental, within Mount Kampalili-Puting Bato KBA. A team from the provincial government was assessing the area’s potential tourism sites when it spotted the birds. Ibañez says a single eagle pair needs 4,000-11,000 hectares (10,000-27,000 acres) of forest to thrive and multiply. While roughly 200 eagle pairs are believed to survive in Mindanao, Ibañez said only 39 pairs have actually been documented. This means more expeditions are needed to get the real numbers, he says. “We are very happy every time we discover new pairs,” Ibañez says. “It is important to locate the nesting sites so that we can put in place protective measures to ensure they will be out of harm’s way so that the species can reproduce and will not become extinct.” The oldest nesting site within Mount Apo was discovered in the 1970s, near its foot. An eagle pair continues to frequent the area today, according to Ibañez. The birds can live up to 40 years.

To help with the conservation of the forest and the Philippine eagles in Mount Apo KBA, the Davao City government engages Indigenous communities through its “Bantay Bukid” (Forest Guard) initiative. Under the scheme, some 200 Indigenous men have been recruited as volunteer forest guards, for which they get a monthly allowance of 2,000 pesos (about $40), to patrol four identified nesting sites. Together, they keep watch over some 25,000 hectares (62,000 acres) of forest.  “With many pairs of eyes watching over the forests, it helped deter timber and wildlife poaching activities,” Ibañez says, noting that the Indigenous women also benefit through livelihood projects. Despite the successes in the field last year, the PEF has taken a financial beating from the COVID-19 pandemic, according to Ibañez and Salvador. The foundation has had to appeal to the public for donations to keep its work going amid the health crisis. “We lost about a third of our revenues … The large chunk of conservation money came from the gate receipts of the center,” Salvador says, adding that the PEF has received the bulk of its funding from corporate and private contributors rather than from the government. With the pandemic still unfolding, Salvador said short-term conservation efforts for the national bird pose a big challenge. But despite the debilitating impact of COVID-19 on the PEF, Salvador says the foundation will try its best to respond to the needs of the Philippine eagles in captivity and in the wild.