Silhouette Island in the Seychelles inner grantics is known as a Global Biodiversity Hotspot, one of the richest in the Indian Ocean. Many of Seychelles’ 85 endemic plant species are found here. BirdLife International recognises the island as an Important Bird Area with habitat for some of Seychelles’ iconic terrestrial species as well as migratory seabirds. Silhouette is also home to the world’s largest colony of the critically endangered Seychelles Sheath-tailed Bat.
Silhouette Island is 93% National Park, its surrounding waters designated a Marine National Park due to its abundant biodiversity and unique natural environment. New and rare species are still being discovered. New threats also are emerging. Dynamic conservation management is an urgent priority for the island.
In this vein, the Critical Ecosystem Partnership Fund (CEPF) recently funded a workshop aimed at developing a new biosecurity program for Silhouette Island.
Seventeen local participants from Islands Development Company (IDC), Island Conservation Society (ICS) and Hilton Labriz Seychelles Resort and Spa recently spent a day learning about the vital role of biosecurity practices to the island.
Training focused on identifying biodiversity risks and highlighted the threats posed by invasive species. Activities included a quiz and the opportunity to design an Entry Protocol for the La Passe Jetty, the main point of arrival onto the island. Trainers Wilna Accouche and James Millet delivered the course jointly in Creole and English. Participants engaged enthusiastically and have already requested advanced training once the program is in place.
Under the GOS-UNDP-GEF Outer Islands Project (OIP), biosecurity training is also being undertaken for the more remote islands of Desroches, Alphonse, Farquhar and Poivre. Despite their seeming isolation, these islands are also highly vulnerable to threats from invasive species, along with unsustainable development and resource management practices. The Outer Islands Project Coordination Unit (PCU) is working in close collaboration with CEPF to produce brochures, posters, banners and signage highlighting biosecurity issues and solutions.
A big thank you goes to CEPF for funding this important work, and to Hilton Seychelles Labriz Resort and Spa, IDC and ICS for empowering their staff to participate in this project for the conservation of Seychelles’ natural environment and beautiful Silhouette Island.
Wedge-tailed Shearwater Colony rediscovered on St Francois Atoll
Saint François Island, at the southern tip of Seychelles’ Amirantes chain, is a haven for thousands of migratory birds. The island hosts small breeding colonies of Black-naped Terns Sterna sumatrana (Dyanman Likou Nwanr, in Creole) and Fairy Terns Gygis alba (Golan Blan) are scattered across the island. Crab Plover Dromas ardeola (Kavalye Loulou) is without a doubt the finest wader species to inhabit the Red Mangrove Rhizophora mucronata forests (Mangliye Rouz), which are also home to uncountable numbers of Fiddler Crabs Uca tetragonon (Loulou Grangalo).
Saint François Atoll in the Alphonse Group sprawls over 5,400 hectares; one-third turquoise lagoons and two-thirds endless reef flats. The second island of the atoll, the tiny Bijoutier Island at just two hectares hosts a large breeding colony of Wedge-tailed Shearwater Ardenna pacifica (Fouke Dezil), comprising over 50 pairs. A second smaller breeding colony at Alphonse Island is threatened with extinction by introduced rats and cats. Nests are protected by a grid of rodenticide bait stations, combined with rat and cat trapping. The colony is closely monitored by Island Conservation Society (ICS) staff, who have been resident on the island since the establishment of its Conservation Centre in February 2007.
Discovering a colony of a burrow-nesting, nocturnal seabirds is challenging. Birds feed offshore during the daytime, only returning to land late at dusk. In the early dawn they depart again to fish. In Seychelles, the breeding activity of the birds is synchronized. Late July – September are generally spent courting and establishing nest sites. During this time the adults’ eerie calls and duets punctuate the skies around the colony site, sounding strangely like the cries of a human baby. Egg laying takes place at the end September / October, the nest expertly excavated to the base of a deep burrow. Throughout incubation and fledging, young birds are inconspicuous inside these well camouflaged burrows. Some aspects of fledging behaviour still remain a mystery. Evidence suggests that parents stop feeding their fattened chick whilst still in its burrow. As its plumage develops to fledging stage, the chick’s hunger encourages it to leave the nest and fly independently to sea. Here it will rejoin its parents to learn how to fly and fish.
Wedge-tailed Shearwaters range across the tropical Pacific and Indian Oceans at latitudes between roughly 35°N and 35°S. As ground-nesting birds they are particularly vulnerable. Threats to populations include loss of food through unsustainable levels of fishing by humans, predation by invasive species such as rats and cats, and predation by humans. Although illegal in many countries, birds are still captured as a food source, including occasionally in Seychelles. Breeding colonies are primarily known from Australia, Saipan, New Caledonia, Hawaii, Mexico, Mauritius and Seychelles.
Early accounts of Wedge-tailed Shearwaters breeding at St. François date from 1951 to 1959. Desiré Gendron, who managed Alphonse Island at that time, reported that the island was home to Fouke Dezil. There were no further reports until more than half a century later, when a fluttering WTS chick was found by Ralph Meyer-Rust, Alphonse Hotel Manager from 2008 to 2013. Ralph’s further investigations in 2013 confirmed the most southerly population of this species known to be breeding in Seychelles.
Since 2013, ICS’ field searches to locate breeding burrows and estimate population size had all failed. However, ICS staff refused to abandon the cause, knowing that success is often reached by walking from failure to failure with no loss of enthusiasm!
Finally, in October 2017, a breakthrough! While conducting a population census of Red-footed Booby Sula sula (Fou Bet) at Saint François Island, where that species night-roosts in spectacular numbers, the Alphonse ICS Team heard eerie calls coming from inside the Coconut Forest.
ICS Conservation Officer Pep Nogués recalls, “Intrigued, with just a couple of headlights and the omnipresent moonlight to guide us, we ventured into the forest. Five birds were sitting on the ground. On detecting our presence, two of them retreated rapidly into their burrows, excavated under fallen coconut leaves. A few other vocalizations were heard in the vicinity. After examining the area until midnight, our opportunistic survey had revealed the presence of at least five active burrows (5 pairs). To avoid further disturbance, we noted GPS coordinates and continued censusing the Fou Bet”. The ICS Conservation Team are justifiably proud of their efforts - undoubtedly, persistent dreamers are the saviours of the world!
Further surveys are now planned, which will help ICS to learn more about the breeding success and population trends for Wedge-tailed Shearwaters in Seychelles. This is a small yet important discovery for the species, and a clear sign that the wildlife of the Outer Islands is recovering thanks to the protection and surveillance that ICS and its partners of the Alphonse Foundation have established over the last decade.
Protected Areas such as these in Alphonse are essential for biodiversity conservation; and biodiversity is vital to support the two most important economies in Seychelles - Tourism and Fisheries.
Conservation efforts across the Outer Islands are benefitting from greater governmental priority under the GOS-UNDP-GEF Outer Islands Project to expand and strengthen the Seychelles Protected Areas system, which had previously focused on the Inner (Granitic) Islands and Aldabra. Expanding the country’s network of Marine Protected Areas within the Seychelles Exclusive Economic Zone is already helping to preserve Seychelles’ natural environment and resources for future generations of Seychellois.
Aurelie Duhec and Richard Jeanne are Island Diehards. Since 2011 this tight team have tackled Conservation Management on the Seychelles Outer Islands of Desroches and Farquhar in the far reaches of the archipelago, working for Island Conservation Society (ICS). Yes, they live and work in one of the most beautiful regions of the Indian Ocean, on some days accompanied only by colonies of seabirds, turtles, sharks and rays. These they monitor daily, providing insights that excite researchers and nature enthusiasts the world over. Of course it's not all plain sailing. When Cyclone Fantala struck Farqhuar in April 2016, their newly established Conservation Centre - one of their proudest achievements for the Island - was completely wiped out, along with almost all the vegetation on the islands.
Yet they soon returned with renewed vigour and great enthusiasm to enact new programmes that now include fish catch and spawning aggregation monitoring, cetacean recording and manta ray population surveys. Then there were the beach clean ups, FAD removal operations and checking in on the giant tortoise population. The GOS-UNDP-GEF Outer Islands Project targets Farquhar, along with Desroches, Alphonse and Poivre managed by ICS, as significant areas for protection, thanks, in part, to abundant marine and terrestrial biodiversity and globally important seabird colonies. With consistent conservation management and monitoring, such as Aurelie and Richard provided, these islands can continue their role of wild refuges long into the future.
As Aurelie says, "There is an end for everything, even for the most beautiful experiences. Richard and I have been extremely enthusiastic to work for ICS in the remote Seychelles Islands where we certainly have written our most exciting chapter of our life".
Thank you Richard and Aurelie, for everything you've achieved during your time with ICS, for your dedication and unfailing good humour. You will be missed. We wish you the very best in your new adventures!
Exciting Sightings of Marine Mammals in Seychelles Outer Islands of Desroches and Alphonse
The ICS Conservation Teams on the beautiful islands of Desroches and Alphonse Group have recently been treated to a natural spectacle as migrating humpback whales visited their sheltered waters and seemed in no hurry to leave.
Since mid-August affiliations of humpback whales, including at least one mother and calf pair, have been spotted playing, resting and feeding close to the islands.
Whales inhabit the ocean, but as mammals they must regularly come to the surface to breathe air, as turtles do. The huge spray of warm air produced by whales as they breathe out is called their “blow”. It can be up to three metres high and can be seen from a great distance.
On Desroches, on the morning of Sunday 20th August, the keen eyes of ICS Ranger Jean Claude-Camille spotted the blow of a whale 300 metres from the beach. Closer investigation aboard an IDC boat allowed ICS Conservation Officer Matthew Morgan to identify that it was a mother humpback with her calf. With the collaboration of two other boats, Russcat belonging to the hotel developers and the ICS boat Torti Blanc, the ICS Conservation Team identified at least three whales breaching within the lagoon in the North West and North East.
Humpback whales Megaptera novangliae leave their Southern Ocean feeding grounds each year and migrate north to breed and calve in warm sheltered waters closer to the equator. Mother humpbacks, in particular, often choose to spend time with their calves in lagoons and shallow waters where they have natural protection from predators such as sharks.
Under the GOS-UNDP-GEF Outer Islands Project carried out by ICS, Conservation Teams monitor marine mammals around Desroches, Alphonse, Poivre and Farqhuar with autonomous acoustic recording devices and sightings. Close encounters are rare and very exciting for all involved. Data collected includes: GPS position, swimming direction, numbers, species and behaviour.
Regular monitoring helps to build knowledge of this important subject, which could help the Atolls gain protected status and open new areas of tourism.
Species identified in the Outer Islands in the past include orcas, sperm whales, bottlenose and spinner dolphins and dugongs, among others.
Many marine mammals are listed as vulnerable or endangered on the IUCN Red List, and the data collected in these remote areas helps to build a strong case for global conservation protection.