Wild Life 2019 Issue 2

At the recent Durrell London Lecture, held at the Royal Institution, we focused on our work in forests around the world. Forests are Earth’s most dominant land-based ecosystem and can hold great significance to people. They often feature in myths and legends, shaping how we interpret our world and are central to childhood stories such as Little Red Riding Hood.

It is not only forests but individual trees that become symbolic to us and our societies. The Ashbrittle Yew, the oldest known tree in the UK, possibly as much as 4,000 years old, has stood sentinel over Ashbrittle through the centuries with countless generations of Somerset children having played beneath its boughs. You may have visited the mighty ‘General Sherman’, a giant redwood or sequoia, in California, the largest known living single stem tree on Earth. It weighs nearly 2 million kg, a true giant of our planet that invokes awe and wonder.

Forests can be split into four types. First, there is the Taiga, also known as the boreal forest, which grows in the high northern latitudes. They are characterised by cold temperatures; think of how vast expanses of frozen forests are used in films to portray icy cold. However, it is tropical forests that dominate the planet’s ecosystems and as the name suggests lie between the tropics of Capricorn and Cancer. Half of all the world’s forest is tropical, which includes both rainforest and dry forest. Temperate forests are sandwiched

between the boreal and tropical forests, and are sometimes referred to as the ‘fourseason forests’. They are highly diverse with coniferous, deciduous and broadleaf trees and even contain temperate rainforests, some of which are found in the UK. The fourth type of forest that could be described are man-made commercial forests, these are often monocultures and have little biodiversity.

At the Lecture, the first speaker of the evening was Professor Miles Richardson, from the University of Derby. He gave a fascinating insight into how connectedness to nature affects our physical and mental happiness, and our likelihood to carry out behaviours, such as recycling, to help the planet. Connectedness to nature is something that is at the heart of Durrell’s strategy, and this was a thought-provoking introduction to the science behind it.

We then turned to Durrell’s work with forests across our rewilding sites including Madagascar, Saint Lucia, Mauritius and the UK. However, the evening focused mainly on our work in Brazil, with our local partners IPÊ, the Instituto de Pesquisas Ecológicas. Brazil is the most biodiverse country on Earth, but it has hit the headlines this year with the horrific burning of the Amazon due to an abdication of governmental responsibility for the environment. It is deeply worrying that such mindless destruction should be allowed. Yet there is another, little known, great tropical forest of Brazil, the Mata Atlantica, or Atlantic Forest, that has suffered even greater destruction over the past century. This extraordinarily lush rainforest extends along the Atlantic coast and inland in southern Brazil and is some 60 million years old. It is home to hundreds of animals and thousands of plants that are found nowhere else on Earth, yet only 12% of its original range persists, in some regions only 3%.

Our connection to the region goes back many years. Durrell has a wellearned reputation as a world leader in the care, management and conservation of callitrichids, the beautiful tiny monkeys of the Americas and none more so than the black lion tamarin. Thought to be extinct in the 1970s, black lion tamarins were rediscovered, and Durrell became the first zoo outside Brazil to hold and breed this species. To this day, we continue to be the only zoo in Europe that keeps these rare and endangered monkeys. Like other species in the forest, they are severely impacted by deforestation, which is happening at an alarming rate. The disappearing forest forces animals to live in small fragments of ideal habitat. Here they become isolated and face an increased risk of extinction from inbreeding, insufficient habitat and the increased dangers from roads, farms and predators when moving between fragments.

Our partnership with IPÊ has deep roots and extends over 30 years. Our very first Brazilian trainee at the Durrell Academy was Claudia Padua, an exceptionally talented young biologist who, on his return home, founded IPÊ and still leads it today. IPÊ has gone from strength to strength, and we continue our collaboration in the field and through staff training. The organisation started building forest corridors in the Pontal region of São Paulo to connect fragmented forest to the Morro do Diabo State Park, the last stronghold of the black lion tamarin. They began by planting the 13km long western corridor, with help from Durrell via our ‘Cans for Corridors’ scheme, which raises money through recycling aluminium cans. This corridor scheme also provided fruitful work and purpose for the Movomento sem Terra, or landless peoples movement, in the area. Instead of viewing them as a threat, IPÊ recognised these people as potential allies and partners. They provided training and land for the people to be part of the project by growing the saplings that would be needed to regrow the forest corridors. As the forest grows, there is also the opportunity to cultivate other crops, such as shade-grown coffee and cassava, providing livelihoods for local people. The western corridor has now been completely planted and, due to the lushness of the tropics, within just a few short years trees can reach over 7m tall. These forests are also rich and diverse with over 150 native tree species being planted, unlike the monocultures of the human-made commercial plantations.

We know via camera traps that animals are moving through the corridors, demonstrating that the concept is working. However, for the black lion tamarins, we found a problem. Although the tiny monkeys were venturing into the corridors, they were not travelling the length of them. This is because the trees in the new corridors were young and did not have as many crevices and

sleeping dens as the old, weathered trees. Black lion tamarins are small and vulnerable to larger predators such as tayra (a small mammal from the weasel family) and snakes. They were therefore understandably nervous about venturing too far without assurances of where they could hide and sleep. We tackled this problem by testing different designs of artificial next boxes at Jersey Zoo in our callitrichid forest where tamarins and marmosets roam free. Our own monkeys essentially chose the nest-box design they liked best for their wild cousins, demonstrating the effectiveness of applied zoo-based research. The selected nest box was placed into the wild corridor and was soon being investigated by numerous species including black lion tamarins. It’s still early days, but we will continue to monitor as this project progresses.

Our next step, together with our partners at IPÊ, is to create a tree corridor to connect the Morro do Diabo State Park to isolated forest fragments to the north. Linking these small patches of rainforest will give threatened populations of black lion tamarin, puma, jaguar and ocelot a chance to thrive again.

With your help, we can restore this lush rainforest by planting trees and creating sustainable livelihoods for local people.

A special thank you must go to Rathbones and Rathbone Greenbank Investments for their generous sponsorship of the Durrell London Lecture for the second year.

IF YOU CAN HELP TO RECOVER THE ATLANTIC FOREST PLEASE VISIT

DURRELL.ORG/ATLANTIC

Rewild carbon

In addition to building functioning, resilient habitat, there is also the need for a world facing catastrophic climate change to tackle the issue of carbon emissions. While the first point of any climate change approach should be finding ways to reduce carbon emissions, how do we mitigate what is left?

There is increasing evidence that tree planting has great potential to capture carbon. A recent report found that there is an identifiable 0.9 billion hectares that can be reforested globally. This would equate to neutralising 200 gigatons of carbon, nearly two-thirds of all emissions in the atmosphere.

IPÊ and Durrell, while primarily focusing on building habitat and protecting biodiversity, have also been contributing to natural climate solutions. Growing evidence also suggests forests that are rich in wildlife, with high numbers of animals are more efficient at absorbing carbon. Therefore, it makes perfect sense that in tackling the two great existential crises of climate change and biodiversity loss, we combine the work. In 2020 we plan to launch our carbon scheme for individuals and companies, ‘Rewilding Carbon’, and this is the first step of that process.