Guest Author:
Tess Gridley, Sea Search
It’s not every day you are invited to a private island – but on that day saying ‘Yes’ seemed like a pretty good idea. So, when my PhD student, Sasha Dines was invited to Ilha do Fogo in Mozambique in February, and there was space for me to join the expedition, I literally jumped at the chance.
Cape Town to Maputo
Not knowing what to expect, and still knee-deep investigating the seal die-off along the West Coast of South Africa, I felt like at the very least this would be a great excuse for something completely different, some much needed down time without the constant demands of leading a sombre 6-month investigation into mass mortality. At best – this could be a great opportunity to scope new research sites, make new friends and experience the coral reefs which first inspired my journey into marine biology some 30 years ago.
What came to pass has exceeded all possible expectations and affirmed fundamental life decisions, which fortuitously cumulated in five days of exclusive island life, bracketed by an exceptional four days of a road trip through rural Mozambique. An experience hard to beat in this lifetime or indeed the next.
Not knowing what to expect or entirely where we were headed, I booked tickets from Cape Town to Maputo and met the team in a humid airport cafe, enjoying beers and excitedly planning the trip ahead. I had been assured that as long as this connection was made all else would fall into place, so on joining the group I could now breathe deeply and relax.
The travel team
Mozambique’s far-flung north
A culture unchanged for centuries, with women working the paddy fields or resting in the shade weaving, sorting grains or pounding maize meal. Men and boys with scythes digging the fields or transporting firewood or charcoal on the back of cherished bicycles. Children bathing in the flooded rivers whilst their elders washed clothes, fished or chatted on the riverbanks.
Ilha do Fogo
Emerald waters bordering untrodden yellow sand, which in turn edged the luminous forest. The only visible manmade structure, a prominent lighthouse jutting high into the blue sky on the northern shore. The Mozambique tides, notoriously strong, pulled the boat back and forth as we edged closer and reversed into a cradle of hands formed by the construction crew and workers based on the island.
The team, well versed in the process, assisted as we stepped off the vessel and formed a human chain to facilitate offloading luggage and supplies. In the midday sun, the water, warmer than any I have ever experienced, offered little in the way of cooling, so we stepped onto the sand and towards the shade of the trees where welcome refreshments awaited. We had arrived on Fire Island.
Mission exploration
There is much yet to understand regarding the history of the island as well as the surrounding seascape. Most recently the island was bought by retired lawyer Bob (as we came to know him) with the hopes of developing a resort destination. However, after seeing the devastating impact of turtle poachers on the island, the dream changed to an overarching goal of conservation.
For Sasha and I, this reconnaissance mission took two gazes, as both a pilot for future guests and scoping for scientists who may contribute to the Island’s conservation mission. Consequently, we arrived armed with an arsenal of acoustic recorders, cameras, gaffer tape and of course every marine biologist’s go-to – cable ties.
Unchartered territory
We had a rough plan of action, but nothing set in stone, knowing that we would need to work around the ongoing construction taking place to establish the island as an eco-resort. But having recently tested out low-cost microphones on land (audiomoths) and their underwater cousins (termed hydromoths), we thought a snapshot of the soundscape of the island both above and below the water line should be possible, laying important foundations for future study.
This would be a study grounded in the relatively new field of Ecoacoustics – whereby acoustic complexity, measured rate, diversity and strength of sounds generated by animals inhabiting the area, is used as a proxy for characterising biological diversity. In remote and unstudied locations such as Fire Island, where species presence or characteristics have not yet been formally characterised, this method warrants fundamental information, which managers can use to understand the rhythms and changes in ecosystems such as those caused by seasonal fluctuation or human disturbance.
Drastically divergent reefs
We looked first to the marine environment, grabbing snorkelling equipment and heading out as an excited team unsure as to what we would see. It became quickly apparent that the reef habitats around the island were drastically different. The pristine southern reefs gleaming with life and populated with countless fish and crustacean species waiting to be documented. Contrasting this at the north facing the mainland, years of unregulated artisanal fishing activity have left the exposed reefs degraded and over-exploited.
At high tide, the overfished habitat is characterised by dead and broken coral, to which ephemeral algae and sea grass have established, hosting turtles and perhaps even seahorses. Juvenile fish dart amongst the reef boulders, a colourful contrast to the drab background. I found myself pitying these youngsters, youngsters trapped amongst the inner degraded reef and stranded at the cheap motel when luxury accommodation was less than a day’s swim around the island to the southern reef.
Unsolicited harvesting
Investigating the island
Island invaders
Of perhaps greater concern was the presence of cats, introduced to tackle an island overrun by rats, who perhaps jumped ship many years hence. The ecological disaster to island communities brought by both species is well documented, and an uncomfortable truth is that the buck ultimately stops with human occupation, which has provided a bridge for both.
Devastation to avian and reptilian species on islands can obliterate established biodiversity, eliminating species, which have long evolved in the absence of these predators. Notably, through both acoustic monitoring and careful observation – I could only confirm one species of songbird on the island, a surprisingly low diversity given the proximity to the mainland (some 80 km), shady canopy and high biomass of insect inhabitants.
Reluctant return home
Were it not for my family back in South Africa, I might have skipped the returning boat this time, instead opting to continue documenting critters lurking in the undergrowth – notably the crickets and cicada, as well as soniferous fish, which were prominent in our snapshot recordings.
Expeditions to map sharks and rays, record crooning humpback whales, and locate the elusive Indian Ocean humpback dolphins will have to wait until our next visit.
Reassured by the generous offer of future scientific expeditions and new acquaintances who quickly became friends, our homeward journey (which was just as spectacular as the departure), was filled with plans for future exploration.
Like the childhood fictional character, Mr Ben, who often undertook unbelievable adventures, we stepped back into the airport and the magic of Mozambique disappeared in the closing of a door, replaced with bullish bureaucracy and an inbox full of emails. But as in all good stories, the memories prevail. Lurking in my belongings – one pink crab claw, collected from the sea floor during our unforgettable SCUBA dive – a sure sign that the last 10 days weren’t just a daydream, but that Ilha do Fogo is truly paradise on earth…