Yellow Crazy Ants, or YCA (Anoplolepis gracilipes), were first identified on Mahe in the 1960s and a decade later on Praslin. In 2009, they gained more notoriety as an invasive species, posing a threat to two Nature Reserve on Praslin: the UNESCO World Heritage Site, the Vallée de Mai, and Fond Peper. With their unique zigzagging movement, YCAs have an effective method of infesting areas by hitching rides with humans or any other means of transportation, allowing them to travel long distances and form super colonies with one or more queens. Additionally, this long-legged ant uses formic acid to paralyze and kill other species, regardless of their size. These characteristics render this species difficult if not impossible, to eradicate.

In 2023, following a possible identification, ICS introduced mandatory surveys to detect the presence of YCA on all of the six islands/atolls with a permanent presence. Following this, three islands - Alphonse, Desroches and Farquhar – confirmed the presence of YCA, prompting the Conservation NGO into action.  

​Desroches Island
On Desroches, the team identified YCAs in an area close to the tortoise sanctuary. This was immediately demarcated, and bait stations with small portions of jam were placed throughout the infested zone. Global Positioning System (GPS) points were taken to monitor eradication progress. By November 2024, the team had not recorded any more YCA on the island. “We acted quickly and effectively, and with the help of our partners, we have so far been able to prevent a re-introduction of YCA,” states Elisabeth Hein, the Conservation Officer on Desroches Island. However, the team is still cautious of a reintroduction through regular boats or flights that arrive on the island and remains vigilant in their monitoring of YCAs on the island.

Farquhar atoll
Farquhar Atoll presented a different challenge due to the extent of the infestation of YCA. Under the leadership of Seychellois Conservation Officer Priya Didon, the ICS team deployed jam bait alongside additional baits, such as Hymenopthor and Fipronil in heavily infested areas on Ile Du Nord where the human population lives. A colony of the Red-footed Booby (Sula sula) – a seabird species nesting on Ile Du Nord– was especially vulnerable given its proximity to the infested areas. Other small uninhabited islands of the atoll have so far remained unscathed. With the infested area demarcated, the team has so far deployed over 700 jam-baiting station on Ile Du Nord. “We are focusing on areas where the presence of YCA is confirmed. Other than that, we only use jam to check for their presence,” Didon states. However, heavy rainfall has hindered their progress, and the team is eager to get the situation under control.

Alphonse Group
On Alphonse, YCA was first detected in 2018 and more recently, has been spreading rapidly. Last year, the team launched a rigorous survey to identify the most infested areas on Alphonse, the main island in the group. According to the Conservation Officer Jack Coupland, the team deployed over 1,168 jam traps out of which 100 had one or more YCA in it. “The broad-scale baiting has helped us to identify areas where the ants are present. Now we are streamlining our efforts into a more localized bait deployment which will significantly reduce the population of YCA in a short period,” states Coupland. ICS is also relying on the expertise of its partners, including the hotels on the respective islands and the Islands Development Company (IDC) in this rigorous exercise which will also include using pesticides in areas where there are human residences and minimal risks to biodiversity. “This is a long-term eradication that will take different methods and concerted efforts by all the partners,’ adds Coupland.

Aride Island
Although Alphonse, Desroches and Farquhar, are the only islands with confirmed YCA infestations, ICS remains vigilant. Monthly surveys are now mandatory for all Conservation Centers, including Aride Island, a Special Nature Reserve which welcomes daily visitors from other islands. “We have amped up our biosecurity measures in view that there is a serious threat of YCA coming on Aride from Praslin,” states Emma Cotton, the Assistant Conservation Officer on Aride Island. “All visitors to the island are encouraged to bring as little as possible and should they disembark with bags, these are thoroughly searched for ants and other pests.” She adds that these measures will hopefully keep the ants away from the island which is an important nesting place for various species of seabirds.
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The impact of Yellow Crazy Ants (YCA) on biodiversity cannot be overstated, and the human and financial resources required for successful eradication are substantial. The control methods and protocols applied on islands with confirmed YCA infestations by ICS, demonstrate that only sustained commitment and significant investment can lead to their eradication.

After years of relying on small backup generators, Aride Island has made a transformative leap towards sustainability by installing a state-of-the-art solar Photo-Voltaic plant.  This milestone project, made possible through generous donations from ICS’s international partners, including the Cadbury Trust, the Bower Trust, and ICS (UK), marks a significant step forward in energy self-sufficiency and the island’s conservation obligations.

Previously dependent on intermittent generator power, the Island Conservation Society (ICS) staff and residents now benefit from 24/7 clean energy. The new solar setup is a 3-phase 42 kWp plant of 99 solar panels, 18 kW of battery inverters, and 92 kWh of lithium-ion battery storage.

Anthony Bentley, Reserve Manager at Aride, highlights the dramatic improvements:
"Our lives have changed dramatically. We used to rely on generators with continuous issues, limited to just 10 hours of power daily—noon to 2 PM and 6 PM to 2 AM. Now, we enjoy full nights of uninterrupted sleep with ceiling fans running, and no one needs to wake up at 2 AM to turn off the generator!"
The benefits extend beyond comfort: fully functioning fridges and freezers ensure that perishable food stays fresh, and chilled drinks are readily available. “The quality of life has improved significantly,” Bentley adds.

The plant supplied and installed over five days by local Seychellois-owned company Energy Solutions Seychelles, promises longevity with solar panels expected to last 25 years, lithium-ion batteries and inverters for up to 15 years. To maximize efficiency, a climate-controlled room now houses the batteries and inverters, ensuring optimal performance through regular maintenance.

The next big sustainability project on Aride is the installation of its first desalination plant. Currently, drinking water is transported from Praslin, but plans are underway to install a desalination plant, providing the island with a self-sufficient, potable water supply.
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This solar initiative is more than a technological upgrade; it embodies Aride Special Reserve’s commitment to environmental stewardship, ensuring that this pristine natural reserve remains a beacon of sustainability for generations to come.

​2024 was a year for birds due to the sheer volume of sightings across Seychelles. These birds often migrate from Europe and Central Asia to Africa, with some stopping on the islands to rest or sometimes they are blown off course. Each observation contributes to a growing archive for Seychelles which is maintained by the Seychelles Bird Records Committee (SBRC). This long-term data helps to build our understanding of the migratory patterns and supports conservation efforts for these species, many of which face threats worldwide.

Aride Island Special Nature Reserve is renowned as an important seabird colony site in the Indian Ocean, boasting the largest population of several seabird species globally. Yet, this year, it was a tree species unique to the island that captured the spotlight: the Rothmannia annae, commonly known as the Wright’s Gardenia or ‘Bwa sitron’ in Creole.
Wright’s Gardenia is endemic to Aride, meaning this small granitic inner Island of Seychelles of approximately 72 hectares, is the only place where this plant species occurs naturally in the world. This extremely limited geographical distribution means that the tree is classified as Critically Endangered and is featured on the Red List of the International Union for Conservation of Nature (IUCN). In the past, this sturdy wood was harvested for firewood and hence in the late 1990s and early 2000 it became rare and then disappeared on all the islands of Seychelles, except for Aride.

The protection of this species has always been important for the Island Conservation Society (ICS) - which manages Aride Island, not only for aesthetics but also for biodiversity conservation. The Wright’s Gardenia has arguably, one of the most spectacular and scented flowers amongst the endemic trees of Seychelles. The white flowers tinged with tiny dots of purple and magenta has been immortalized on the 25 rupee note of Seychelles and stamps of Seychelles. The fruit itself is not a lemon or “sitron’ as its Creole name suggests, as - although folkloric says it is edible – it does not have many purpose in the local cuisine. Albeit its lack of purposeful use in modern times, ICS have collaborated with many organisations and individuals to reintroduce this endemic plant species on other islands. Hence, the Wright’s Gardenia can be spotted on islands such as Fregate, Silhouette and even on Praslin and Mahé.

On Aride, the Wright’s Gardenia grows best in rocky, nutrient-poor soil, mostly around the highest parts of the island.  Every five to seven years a detailed census is undertaken to locate and tag each tree growing on the island. This year, it took a team of eight staff and volunteers, 272 hours to find all the trees through dense foliage and challenging terrain. Once a Wright’s Gardenia tree is found, it is given a metal tag with its number on it, or if it is an old one, its tag number is recorded. A GPS point is recorded so the spread of the species across the island over time can be charted. Its height is also recorded, and any surrounding saplings, fruits and seedlings are counted. 

The result was astounding: a total of 2,913 trees, nearly 1,000 more trees than found in the last census in 2017. Some trees had over 1,000 seedlings, which indicates that this species is thriving on the island.