IN THE WILD

FIGHTING CHYTRID IN THE FIELD

The deadly chytrid fungus has driven the decline of over 200 species of amphibian worldwide, including the mountain chicken frog. With only two mountain chickens remaining on their native Montserrat, novel methods are urgently required to enable reintroductions in the face of such irreversible threats. Chytrid is known to have a narrow thermal tolerance, not being able to withstand temperatures above 29°C. Using this knowledge, Durrell scientists have been able to put together a reintroduction plan for the mountain chicken based on enclosed habitat manipulation.

The semi-wild enclosures in Montserrat have been designed so that our scientists can artificially change the temperature of certain areas to mitigate the spread of infection – a world first in a wild setting. In 2018, we repurposed an old volcano shelter on the island as an insect-breeding centre to provide food for the enclosed frogs in lean times and provided training to three local forestry officers in captive insect breeding. We have also trialed techniques for sustainably heating the outdoor ponds and measuring the rate of chytrid found in these areas in comparison to the unheated habitat. Reintroductions of captive bred mountain chickens are planned to take place in July 2019.

CONSERVATION SUCCESS FOR MAURITIAN REPTILES

The Red List of Threatened Species, compiled by the International Union for Conservation of Nature (IUCN), is the most widely recognised assessment of the global conservation status of species. Moving down this list indicates a species is becoming less at risk of extinction, which represents a major conservation achievement often involving years of concerted effort. We are pleased to announce that two species, the Round Island boa (Casarea dussumieri) and Günther’s gecko (Phelsuma guentheri), have made this move towards conservation safety as populations are increasing and becoming more secure. Key actions that have led to this improvement include the removal of goats and rabbits from Round Island in the 1970s, the restoration of native flora and the establishment of new populations of both species on other islands. However, work doesn’t stop there. These populations are still extremely vulnerable and efforts to continue their restoration are central to our rewilding plans for the offshore islands of Mauritius.

PLANNING UNDERWAY IN ST LUCIA

Our St Lucia Racer appeal raised over £10,000, which is a fantastic result. Thanks to your generous donations, we have launched our effort to save the Critically Endangered St Lucia racer snake alongside our partners Flora and Fauna International, the Saint Lucia National Trust and the Government of Saint Lucia. The first step will be to establish a facility to breed the snakes in captivity to ensure the survival of the species. A planning workshop for the project took place in January which was attended by Dr Nik Cole, who leads our Mauritian islands recovery work, Matt Goetz, our Head of Herpetology in Jersey, and Luke Jones, who is setting up a facility for mountain chicken frogs on the Caribbean island of Montserrat. They agreed on the final designs for the centre, the key steps needed to build it, how to establish a food source for the snakes and how to remove snakes from the wild population. This process is due to take place over a two-year period. After the breeding facility is built it will be managed with no snakes for up to a year, which is essential to make sure it is ready to receive the racer snakes before they are introduced in the second year. In the meantime, Saphira Hunt, who works for both the St Lucia National Trust and Durrell, will survey the remaining wild snakes to track changes in the wild population. With fewer than 20 individuals remaining in the wild this is a truly ‘Durrell’ project that is using expertise from across the organisation to save endangered species.

SETTING OUR SIGHTS HIGH!

In April 2019, we began trialling a new method of monitoring Alaotran gentle lemurs at Lake Alaotra in Madagascar – by drone! The method has been developed with partners at Liverpool John Moores University and piloted with our captive lemur population in Jersey. If this initial piloting phase is successful, a plan will be developed for the first range-wide drone survey of the species. Using drones instead of traditional distance sampling methods from canoe, will allow our team to survey across the entire range of the species, producing more reliable population data and ultimately helping us to improve our conservation strategies in Alaotra.

MONITORING CRITICALLY ENDANGERED SPECIES IN MANAS NATIONAL PARK

As part of the Pygmy Hog Conservation Programme, we have established new populations of hogs in three protected areas across the species’ native range in Assam, India. Building on this success, we are now focusing our attention on Manas National Park, which is home to the source population for our breeding programme. Grasslands have undergone a massive decline over the last 30 years and little is known about the state of hog populations in this region. We have a vision of restoring a healthy and diverse grassland ecosystem, which will involve bringing back large numbers of grazing animals. But first, we have developed a camera trap survey grid in which a network of cameras are used to identify any animals in the area. We have proven this approach as a tool for counting hogs in Orang National Park but these surveys will be on a far larger scale and will take much of 2019. The grid will remain in place for three weeks at a time and then all images will be downloaded and analysed. The grid will then be moved to a new location to collect more images. Whilst trialing this technique we have had to contend with inquisitive elephants and illegal fires, which have destroyed a number of our camera traps. New toughened camera housing and an extra coating of chilli paste to deter elephants is now being used to protect the equipment.

Our newly launched appeal aims to fund a 4x4 vehicle for the team in Manas, allowing them to move to the different grasslands within the National Park. Please consider giving what you can to the appeal – this vehicle really will make a huge difference to the lives of the field team and the species they work to save in Assam.

ROUND ISLAND FIELD STATION GETS THE GO-AHEAD

Following the fundraising success of the Rewild our Islands appeal launched at last year’s London Lecture, we are now able to start the build of a brand new field station on Round Island. The new field station will enable us to accommodate the growing number of full-time conservation staff needed on the island to deliver our whole-island restoration strategy. The station will also include biosecurity and quarantine facilities that will support the recovery and re-introduction of some of the most endangered species on Round Island and Mauritius.

TOM CADE 1929-2019

REMEMBERING A CONSERVATION LEGEND

BY PROF. CARL JONES

In early February, one of the great conservation biologists who shaped the way we work with endangered birds sadly passed away. Tom Cade, was an American ornithologist who founded The Peregrine Fund and was responsible for the restoration of the peregrine falcon in North America. He was a pioneer who developed many techniques for endangered bird conservation, but also a modest and unassuming man whom I first met in 1975. Tom was one of the architects for the restoration of the Mauritius kestrel as well as other Mauritian birds, and also a major player in our work with bird conservation in Madagascar.

Tom was a university academic and one of America’s most respected ornithologists who headed up the Cornell University Laboratory of Ornithology. Here he established a captive breeding facility for birds of prey and, working with his students, he developed many techniques including artificial insemination, incubation, hand-rearing, and fostering and cross-fostering to wild birds as a reintroduction technique. Tom was a falconer and therefore he could merge the modern scientific approaches with the traditional ones of falconry such as hacking, the soft release technique based on an approach that dates back to the middleages.

The breeding and restoration of the peregrine falcon was the first time anyone had taken a wild species and restored it in nature using such a range of innovative techniques, integrating science with captive breeding. Tom was a pioneer of the paradigm that many of us are part of, learning how to manage endangered species in nature.

Tom visited Mauritius many times. He and his wife Renetta once spent a whole field season with us and they managed their own release site for Mauritius kestrels. Every evening, after a day in the field, he would come to see me and would describe what he had seen with child-like excitement. Spending time in the field with Tom was inspirational, for he did not think like other scientists I have worked with. Tom spent much time carefully watching and thinking, using a falconer’s intuition, with a scientist’s objectivity. The resulting depth of knowledge allowed him to understand complex problems and to find solutions. It is Tom who demonstrated how to empathise with species and yet still be able to interpret observations with the logic of a scientist.

I have many happy memories of Tom and we did many trips together including one to Arizona to see the California condors that The Peregrine Fund had reintroduced. The last time I saw Tom was when I attended his 90th birthday party, it was a great occasion of celebration, Tom surround by family and friends all telling stories about his adventurous and creative life. We have lost a giant of a man and I hope his soul is soaring with the condors, falcons and eagles whose populations he helped restore.