The Wet Tropics’ wildlife is celebrated worldwide. Its cultural heritage? Not so much

Barry Hunter, Indigenous Knowledge; Alice Buhrich, James Cook University; Asa Ferrier, La Trobe University; Gerry Turpin, James Cook University, and Patrick Roberts, Max Planck Institute for the Science of Human HistoryThe Wet Tropics of Australia — rainforest stretching 450 kilometres along Queensland’s coastline — is renowned for its vast array of wildlife and ancient plant species. It’s little wonder the rainforest is recognised as a UNESCO World Heritage Site, one of 20 in Australia.

However, the cultural heritage of the Wet Tropics isn’t recognised or celebrated with quite the same gusto, with the world heritage listing failing to acknowledge the rich, ongoing significance of Aboriginal culture.

Our recent paper assessed existing archaeological, paleoenvironmental, and historical evidence. And we showed the diverse ways these forests are globally significant — not just for their ecological heritage, but also for preserving traces of millennia of human activities.

But there’s much scope for cultural recognition to go further on a national level, too. While the Wet Tropics’ National Heritage Listing recognises Indigenous heritage, Traditional Owners should have more freedom to manage the region in our holistic way. This would lead to better outcomes for the environment.

The cultural significance of these rainforests

Aboriginal rainforest people used a wide variety of forest resources. For example, studies of ancient plant parts and stone tools show these communities were processing often-toxic rainforest nuts for eating from as early as 5,000 years ago.

Cassowary by the road — Cassowaries may have once been tamed and then eaten in ceremonial feasts.
Rene van Raders, Author provided

They also hunted local animals, such as tree kangaroos, pythons and wallabies. And they may even have captured and tamed the enigmatic cassowaries, later feasting on them during large ceremonial gatherings.

Rainforest people also used tropical forest plants for medicine and to manufacture artefacts. They also manipulated them – for example, evidence shows Aboriginal people strategically used fire to keep open pockets clear of invading rainforest for campsites and ceremonial grounds.

Their skillful forest management enabled pre-colonial Aboriginal populations to survive all year round in rainforests characterised by high humidity, rainfall, cyclones, heat, and dense vegetation.

Today, we can still see Aboriginal people’s ecological legacy in the region, such as through the clusters of rainforest food trees near cultural sites.

The long fight for recognition

Aboriginal rainforest occupation and land management was majorly impacted with European settlement across the region, and the subsequent clearing of rainforest for agriculture.

Aboriginal rainforest people were forcefully removed from their traditional lands and resettled on reserves and in missions, often far away from their homelands.

Traditional land practices were suppressed, which caused these rainforests to change. Weed infestations and feral pigs became widespread. Likewise, the rainforest understory thickened, as any area not felled by Europeans was left to “look after itself”.

Ferns — After Aboriginal people were forced from their land, the rainforest understory thickened and became a bushfire risk.
Shutterstock

These changes have exposed both biological and cultural heritage to increasingly intense fires, such as those we saw in the horror bushfire season of 2019-2020.

Since the World Heritage Area was declared in 1988, rainforest Aboriginal peoples have campaigned to be included in management plans.

In 1998, they produced the seminal report “Which Way Our Cultural Survival”, which reviewed the significant contribution rainforest Aboriginal people make to managing the Wet Tropics World Heritage Area.

Finally, in 2012, the Australian National Heritage List recognised the Wet Tropics’ cultural values. This is extremely important because it gives rainforest Aboriginal people a seat at the table in management decision making.

Rat kangaroo — The northern bettong (or ‘rat kangaroo’) is one of the species benefiting from Indigenous knowledge.
inaturalist/Wikimedia, CC BY-NC-ND

Rainforest Aboriginal people’s long fight for recognition in the Wet Tropics is now turning into direct action, as we apply our unique knowledge to Country. Today, Indigenous land and sea rangers manage biodiversity, threatened species, waterways and water quality, and we care for country through fire management programs.

For example, there are numerous management plans for threatened species that need a defined fire regime. This includes the northern bettong, whose forest habitat on the edge of rainforest requires frequent burning to keep the understorey open and grassy. Indigenous knowledge forms the basis of this.

But our campaign isn’t over yet

On a national level, we need to manage Country as a “whole”, not just one species at a time.

Fire is an integral tool for this management, and we need to apply the right fire for the right Country (something we’re showing through the Firesticks Alliance Indigenous Corporation). In traditional fire management, the dominant tree species and soils in a specific area determines the fire to apply to Country, and at what time of year. There’s no “one size fits all” solution.

A few people surround a small fire — Indigenous land managers care for country through fire management programs.
Gerry Turpin, Author provided

Our research paper makes it clear “long-term” perspectives from oral history, archaeology, history, and paleoecology can make important contributions to conservation management plans for threatened species. This includes the northern bettong, cassowary and tree kangaroo.

Knowledge from Traditional Owners can also add important information on vegetation change over several decades. This knowledge allows us to reconstruct vegetation changes since European settlement. It also provides insights into past Aboriginal use of plants and animals, and mapping cultural sites and walking routes.

One example shows the potential for this. In September 2019, a Queensland government grant supported Jirrbal Traditional Owners to return to Urumbal Pocket, an archaeological site on the upper Tully River. Jirrbal Traditional Owners undertook surveys to identify imprints of past human activities left on the landscape.

A view of Urumbal Pocket from opposite side of the Tully River.
Asa Ferrier, Author provided

They found significant changes to the region’s biodiversity since the removal of Aboriginal land management around 100 years ago. They noted, for example, that no new trees were naturally growing, and remnant sclerophyll tree species were dying, enhancing the rainforest takeover.

The visit also helped Traditional Owners reconnect with their Country, and initiated discussions relating to contemporary burning and other land management tools.

We need equal recognition of the Wet Tropics’ natural and cultural values, and more detailed investigations into how people shaped the rainforest. This will help raise awareness of the international importance of the cultural heritage, and eventually help get it recognised by UNESCO.

And this will help more Australians see the rainforest as a cultural landscape – one that has been managed and maintained by people, rather than just a relic unchanged since the dinosaurs.

The authors gratefully acknowledge the contributions of Ellen Weber from the Wet Tropics Management Authority.

Barry Hunter, Djabugay Aboriginal Corporation, Kuranda, Indigenous Knowledge; Alice Buhrich, Adjunct Researcher, College of Arts, Society and Education, James Cook University; Asa Ferrier, Honorary Research Associate, La Trobe University; Gerry Turpin, Ethnobotanist, James Cook University, and Patrick Roberts, Research Group Leader, Max Planck Institute for the Science of Human History

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Camera traps completed one of the most thorough surveys of African rainforest yet

Mattia Bessone, Liverpool John Moores University and Barbara Fruth, Liverpool John Moores University

Tropical rainforests are the world’s richest land habitats for biodiversity, harbouring stunning numbers of plant and animal species. The Amazon and the Congo basins, together with Asian rainforests, represent only 6% of Earth’s land surface, and yet more than 50% of global biodiversity can be found under their shade.

But observing even the most conspicuous species, such as elephants and apes, is still an extraordinarily difficult task. That’s not even mentioning all the secretive species that are protected by thick vegetation or darkness.

Camera traps have led a technological revolution in wildlife research, making it possible to study species without humans needing to be present. They can be left in the depths of a forest for weeks, taking pictures of anything that moves at any time of day or night.

Installing camera traps in Salonga National Park.
Jonas Abana Eriksson/PNS Survey, Author provided

From their advent three decades ago, camera traps have allowed scientists to discover species such as the grey-faced sengi – a new species of giant elephant shrew living in Tanzania – and the Annamite striped rabbit in Vietnam. They revealed that lions still wander the Bateke plateau in Gabon, ending speculation that they were locally extinct. They also photographed the offspring of the elusive Javan rhino, which scientists had thought had stopped breeding. With fewer than 100 individuals left, this gave hope that the species could be saved from extinction.

The grey-faced sengi (*Rhynchocyon udzungwensis*) was discovered by camera traps in Tanzania.
F Rovero/Wikipedia, CC BY-SA

Spotting stripes

Camera traps are becoming essential for documenting forest species, assessing their distribution and studying their behaviour, as well as counting what’s actually there.

This latter measure, called animal abundance, is perhaps the most important information in wildlife conservation, as it allows researchers to assess the conservation status of a species. But until recently, camera traps could only be used to reliably estimate the abundance of animals with conspicuous markings, such as big cats with spots or stripes peculiar to single individuals.

Big cats, like this African leopard (*Panthera pardus*), are among the simplest species to document with camera traps.
Haplochromis/Wikipedia, CC BY-SA

Counting animals with camera traps remained impossible for the majority of species that lacked these conspicuous features, as the same individual could be counted twice by different cameras at different times. Methods that account for how animals move in and use their habitat were developed to help overcome the problem of detecting the same individual at different locations.

Another method, called camera trap distance sampling achieves the same result using a different approach. It subdivides the time cameras are active into “snapshots”, taking pictures at, for example, every fifth second in an hour. At a determined moment, an individual can only be spotted at one location, not elsewhere. Double counts are avoided, and researchers get the number of animals within the area surveyed by the cameras at a given snapshot.

We tested this new method in one of the most remote areas of the planet – the southern part of Salonga National Park, a world heritage site in the Democratic Republic of the Congo. Here, rangers only had data on the park’s two flagship species – the forest elephant and the bonobo. Near to nothing was known about the other animals that were more difficult to track.

A flagship species of Salonga National Park, bonobo populations are understudied in 70% of their range.
Christian Ziegler/LKBP, Author provided

What we found

Five field teams walked a forest the size of Wales to deploy 160 camera traps in 743 places. This unprecedented effort produced more than 16,000 video clips, totalling 170 hours of animal footage and revealing 43 different animal species, including bonobos and elephants.

We also captured species rarely detected by human observers, such as the giant ground pangolin, threatened by extinction, the cusimanses, a genus of social mongooses, and the stunning Congo peafowl, a vulnerable species that’s endemic to the country.

Where so far conservation of elusive species such as the African golden cat, the endemic Allen’s swamp monkey and another elephant shrew, the four-toed sengi, had to be based on little to no data, we’re now able to estimate their abundance in the wild.

Nine of 43 species captured by camera traps in Salonga National Park, DRC.
PNS Survey, Author provided

For some species, the news from our findings were good. Our study revealed that the southern part of Salonga National Park alone harboured as many peafowls as were previously thought to be present in the whole country.

For other species, the results confirmed the need for greater protection. The 17,000 km² large and intact primary rain forest contains fewer than 1,000 giant pangolins. An alarming figure given the current illegal trade of pangolin scales.

As the technology and methods of camera trap surveys improve, they’re becoming capable of monitoring a diverse range of wildlife, from the tiny elephant shrew to the mighty forest elephant. This gives an insight into the complex and delicate equilibrium of the rainforest community and the threats to its survival.

Mattia Bessone, PhD Researcher in Conservation Biology, Liverpool John Moores University and Barbara Fruth, Associate Professor, Liverpool John Moores University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Papua New Guinea Rainforests Being Destroyed

Rainforests

Good news on rain forests: they bounce back strong, storing more carbon than thought

Susan Letcher, Purchase College State University of New York

When you cut and burn a tropical forest, you’re left with a barren plain of cracked red mud, incapable of supporting life – the opposite of the teeming, hyperdiverse array of life that was destroyed. Once the trees are gone, the nutrients wash away and the soil degrades into a dense, brick-like layer so hardened that plant roots can’t get through it.

This was the vision of tropical deforestation held in the popular imagination for many years, but the reality is more complex – and more hopeful.

In recent decades, researchers have found that tropical forests are remarkably resilient. As long as some remnants are left when the forest is cleared to provide seeds and refuges for seed dispersers, tropical forests can grow back with astonishing speed.

In a paper published this week in Nature, lead author Lourens Poorter and a team of international collaborators, including me, found that forests in Central and South America can quickly rebound without human intervention on land that has been cleared for cattle grazing or growing crops.

This finding has important implications for climate change because these so-called secondary forests soak up large amounts of carbon from the atmosphere, even without costly reforestation efforts. These regenerating forests are also crucial for protecting biodiversity and all the ecological and social benefits it provides.

Dr. Letcher in a 15-year-old secondary forest in Costa Rica.
Susan G. Letcher

Carbon sponges

Tropical secondary forests – that is, forests that grow after a major clearing, such as a fire, farming or logging – cover an increasing part of the globe. And as their extent expands, so does their potential to shape conservation strategies, both at the local and global scales.

At the U.N. Climate Summit in 2014, 30 nations and a host of NGOs and private companies endorsed the New York Declaration on Forests, a document that advocates halving deforestation by 2020 and ending it completely by 2030.

One of the key points of the declaration calls for the restoration of 150 million hectares (about 375 million acres) of degraded forest land by 2020 and additional restoration in the following decade.

But active forest restoration can be an expensive process, and it may not be cost-effective or even necessary in every case. In landscapes with low levels of degradation, simply protecting young forests and allowing them to develop may be the best strategy.

In our research, my colleagues and I present the largest data set yet assembled to investigate forest regrowth in the New World tropics. The data set spans 45 sites in the lowland tropics from wet forest to dry forest, with a total of 1,478 plots and more than 168,000 individual trees.

It offers an unprecedented, and more hopeful, view of forest recovery.

According to this analysis, tropical secondary forests have enormous potential for removing carbon from the atmosphere. The net carbon uptake for these secondary forests is 11 times that of old-growth forests in the region we studied.

The rate of biomass recovery varies widely across the region, with the fastest regrowth in areas with high rainfall. The median time for a forest to reach 90 percent of old-growth biomass levels was 66 years, but recovery can be much faster in some areas.

Big win for biodiversity

It shouldn’t come as a surprise that tropical forests can grow back after major disturbances. Tropical forests can be affected by a number of different large-scale natural disasters like floods, fires, landslides, major storms and volcanic eruptions.

Even old-growth tropical forests are highly dynamic systems, marked by cycles of tree death and regrowth. The mortality rates for trees larger than 10 centimeters in diameter have been estimated at one percent to two percent per year for forests in the Amazon and Central America. In other words, at the upper end, one in every 50 large trees will fall in the course of a given year.

The gaps in the forest that result from treefalls are rapidly colonized by a riot of vines and fast-growing tree saplings. The heterogeneity of habitats produced by this cycle is a major driver of tropical diversity.

In an old-growth forest, vegetation quickly grows in to fill the gaps left by fallen trees.
Susan G. Letcher

In addition, the history of human-induced disturbances in tropical forests is longer and more complex than we often acknowledge.

Legacies of ancient human use, stretching back for millennia, have been detected in nearly every “pristine” tropical forest on earth: massive earthworks in the Amazon and modern-day Cambodia; charcoal and pottery fragments in the Congo Basin; and evidence of forest clearing going back nearly 50,000 years in Papua New Guinea.

Indeed, various forms of slash-and-burn cultivation have been practiced for millennia throughout the tropics.

As long as the cleared areas are modest in size and the period between cycles of cultivation is sufficient for recovery, diverse forests can persist for thousands of years.

Local and global benefits

Tropical secondary forests can – and should – form a substantive part of the long-term global strategy to combat carbon emissions and preserve biodiversity for the future.

Our recent research shows, for example, that in areas where biomass recovery is slow – like the tropical dry forest – we should prevent further forest loss. Where recovery is rapid, we can combine old-growth forest conservation with policies that promote secondary forest formation.

Shifting focus to the conservation of regenerating forests should not take away from the urgent imperative to conserve the remaining uncut tropical forest.

The clearing of old-growth tropical forests is a major source of human-induced greenhouse gas emissions, second only to fossil fuel combustion. Clearly, keeping the carbon that’s currently stored in intact tropical forests from being released to the atmosphere should be a priority.

Old-growth tropical forests also harbor immense biological diversity – including genetic diversity – and if all of the remaining old-growth forests in a landscape are cut, there will be no seed source to promote regeneration.

Conserving secondary forests offers a different, and complementary, set of benefits.

As well as their massive potential for taking up carbon as they grow, secondary forests provide resources and livelihoods for the people who inhabit them.

Secondary forests can harbor a high diversity of ethnobotanically important species that can be used for medicines. They can serve as extractive reserves, where limited harvesting of timber, game animals and other forest products will prevent the exploitation of resources in vulnerable protected areas. They protect watersheds and prevent erosion.

Natural forest regeneration in Paraná, Brazil.
Robin L. Chazdon

As secondary forests grow back, they eventually come to resemble the forest that was cut, and in the meantime, they knit together the remaining fragments of forest into a more contiguous landscape.

As David Quammen wrote in “Song of the Dodo (1997),” isolated populations of organisms in forests lose connections to the resource base that supports them. Over generations they lose their genetic diversity, making them more vulnerable to inbreeding, disease, and eventual extinction.

Secondary forests offer the hope of reconnecting habitats and creating a more resilient landscape for the future.

So harnessing the power of forest regeneration in the tropics will have benefits both locally – providing resources and restoring ecosystem services – and globally, by sequestering carbon from the atmosphere.

At the Paris Climate Summit, leaders took important steps toward halting deforestation. Promoting forest regrowth is another vital piece of the equation. It’s time for policymakers to recognize the benefits that tropical secondary forests provide, and to shape policies that take advantage of this enormous potential.

Susan Letcher, Assistant Professor of Environmental Studies , Purchase College State University of New York

This article was originally published on The Conversation. Read the original article.