I have been coming to the island of Nusa Lembongan (situated in the Java Sea) for almost eight years and the place never seems to disappoint even though with each subsequent visit I notice changes occurring along the seashore.

Blessed with spectacular views of Mt Agung, on Bali’s eastern shore this tropical hideaway is increasingly drawing more and more visitors from around the globe to discover its many delights.

With each passing year tourist numbers grow exponentially and consequently the island is now serviced by a fleet of fast boats, ferrying scuba divers and snorkelers eager to explore this tropical underwater wonderland. However, with tourism comes the inevitable slow destruction that we humans bring with us. No matter how, ‘eco’ we claim to be, we arrive with our western pollutants and inadvertently damage the environment that we ooh and aah over.

Sun screens, sun tan lotions, run off from the new villas that line the shores and of course the fuel spillage from the boats has virtually decimated the seaweed farming industry that was once the main employer on the island.

These days it is the lure of the giant mantas, which bring the divers to Manta Point on the most southern tip of Lembongan’s much larger sister island Nusa Penida.  It was to there we headed early one Saturday morning, a rather lengthy sea journey on a small boat to where the manta’s feed.

We are fortunate as we are the first to arrive  and, to our delight the mantas are there in abundance. Getting into the water and swimming with these huge creatures is at first a little daunting as, when one is in their environment  they begin  ‘flying’ through the water directly at you, their massive mouths agape and, for me this was a touch terrifying.

The mantas that inhabit these waters are part of the genus manta and are the larger of the manta Birostas, reaching up to 7mts (23ft) in width. These eagles of the sea have triangle pectoral fins and gigantic forward facing mouths. This can be a little disconcerting but even though it looks terrifying the "mouths' are actually huge filter feeders allowing the creature to swallow vast quantities of zooplankton that they  'hoover' into this cavernous opening.

It is surreal experience swimming amongst these creatures that glide around, above and below you like performers from Cirque de Soleil and, for a while you become part their magical world. Their antics are incredible to watch as they soar like eagles down to the depths and then rise up, passing the swimmer with phenomenal speed.   These mantas are however under threat and have been listed as endangered by the International Union for Conservation of Nature.

They are relentlessly pursued by illegal fishermen who poach them and for their copious gill nets, which feeds a demand in the Chinese medicine industry.  Of course pollution (namely plastic) of these wonderful waters is not helping and neither is the number who perish from being caught in discarded fishing lines and nets.

For the moment though we revel in being in this particular corner of the world. Swimming with these creatures is a little like being surrounded by a massive herd of elephants so impressive is their size. At one point we see one of them shoot like an arrow to the surface to breach or leak high into the air before falling back with mighty splash. Why they do this have puzzled marine biologists for years…I personally think they are jumping for joy!

What is encouraging in Indonesia is that the government has classed the mantas as a protected species and it is now illegal to catch or kill them.  A dead manta provides anywhere between $40 to $500 income for those who poach them which on some of the poorer islands constitutes a fortune. During their lifespan a manta can generate over $1 million in tourist income from those who make the journey to see them in their natural habitat … so really, no contest.

Our sojourn in the water ends as we see a number of boats on the horizon heading our way with the same agenda as we had which is to feel blessed to have had the opportunity to swim with these wonderful specimens.  With their dwindling numbers we can only hope that conservation measures offer some protection for without them, the world will be a much poorer place.

Photography Copyright Tony Scott, Paul v Walters & E . J . Lenahan