The restaurant floats a little way from the mangrove-covered bank of the klong.

Most visitors to Phuket stay, naturally, on the west coast. This is, after all, where the best beaches are. Some may venture to the other side, particularly when heading for a day out in Phang Nga Bay. But even these people will probably miss the Bang Rong Community restaurant with its excellent, cheap, halal food.

The waves that grind up dead coral to make that fine, white, powdery sand for which Phuket is so famous are gradually eroding the island’s west coast, eating it away. The breakers have already eaten through the land bridge that once connected Phuket to neighbouring Phang Nga.

The all-wood restaurant creaks slightly as people walk around.

Not to worry; while the island is receding on the west side, it’s growing on the east coast, thanks to the remarkable mangrove. This weird tree, standing above the tide on its extraordinary tangle of roots and with the ability to absorb sea water and eject the salt, holds together the mud that flows down the island’s klongs, creating new land that can eventually be colonized by other plants.

Mangrove forests are also the nursery for many types of crabs, shrimps, prawns and reef fish. Mangroves form one of the three major marine ecosystems in tropical Asia, the other two being sea grass forests and coral reefs.

The uniquely twisted roots of the mangrove tree allow it to process sea water into fresh water.

Local fishing communities have long known this and have in some cases had serious confrontations with other people, particularly prawn farmers, whose activities threatened to damage or destroy the mangrove ecosystem that supported the fishermen’s livelihoods.

Just seven years ago one local eco-warrior was shot dead and another seriously injured in Phuket during a deadly dance with a prawn farm owner, who was eventually arrested on conspiracy charges. His right-hand man was jailed for murder.

In Bang Rong, however, the mainly Muslim community is well organised to nip such confrontations in the bud. Eleven years ago local people set up the Bang Rong Community Fund with 20,000 baht. Apart from preserving the environment, the fund was also aimed at helping the poor, particularly the elderly. Assets now top 20 million baht.

Central to the fund’s income, and certainly its most visible manifestation, is the floating restaurant near Bang Rong Pier, one of the main jumping-off points for boats heading into Phang Nga Bay.

About 100 crab-eating macaques live among the mangroves.

Reached via a raised walkway along the edge of the water, the restaurant floats on the muddy Klong Bang Rong, with views of mangroves on both sides. The menu is halal, mostly southern Thai, with very fresh fish and shellfish taken live from large keep-nets in the middle of the restaurant or from “farms” in the klong. Because this is a mainly Muslim community, only soft drinks are served. The food is delicious, in generous portions and prices are very reasonable, especially given the surrounding scenery.

Kayaks are also available for hire at 200 baht per boat per 30 minutes, with a local paddler provide for those who are not too sure of their skills. The half-hour is ample time to paddle up the klong, taking a look at the fish and shellfish farms along the way, and watching kingfishers and swiftlets on the lookout for food.

Mangrove forests have a complete mini-ecosystem, at the apex of which is the crab-eating macaque, a medium-sized monkey. There are about 100 of these in the neighbourhood of the restaurant. Presumably they do catch and eat crabs from time to time, but they’ll also take any other food that’s going – whether willingly donated or snatched.

One venerable member of the troupe, a one-armed chap, even goes every day to one of the local shops for his morning wake-up – a can of iced coffee.

After a good lunch, visitors can take a gentle canoe tour of the klong and mangroves.

Despite the animals’ apparent charm, visitors are advised not to feed the monkeys, which can sometimes be bad-tempered, especially if one teases them by offering and then withdrawing titbits. These animals have long, sharp teeth and strong jaws, and can move frighteningly fast. Admire them from a distance.

The klong itself teems with fish, especially the one Thais call pla khem, or needle fish. Schools of these long slender fish, each with its yellow-tipped snout, hang around the restaurant waiting for anything diners care to throw to them. Prawn tails and bits of crab shell are very much appreciated.

In the next couple of years the community fund plans to build a walkway through the mangrove forest, allowing visitors to get close up to these remarkable trees and to watch the wildlife that thrives among their roots and branches.

In the meantime, the restaurant is well worth a visit for a leisurely lunch and a lazy afternoon with friends. And with no alcohol served, it’s also a fine hangover cure.

To get to Bang Rong Pier, drive east from the Heroines Monument for 10 kilometres. On the right you will see a large mosque under construction. Turn right just before it. At the end of this small road is a kiosk where a man collects a fee for parking in the car park next to the pier. Tell him you are going to eat, and you will be exempt from this fee. The entrance to the restaurant is on the left just as you get to the car park. It is open from 9 am to 6 pm.

A crab-eating macaque takes a break in the branches of a mangrove tree.

Everyone knows about coral reefs in the waters around Phuket, and the gorgeously coloured fish, starfish, crabs, prawns and anemones – even worms – that make a living in or on the coral. Certainly, anyone who has not dived or at least snorkeled around the reefs is missing a great deal of the wonder of Phuket.

But far fewer people know about the mangrove forests that are inextricably connected to the reefs, and which are just as important to the marine ecology as the coral.

Mangroves, those odd, smallish trees with weird roots that grow along most of the muddy east coast, lack the grandeur of other species of trees. They don’t put out great cascades of flowers, or perfume the night air. They are, frankly, a bit like that nondescript fellow you meet in the bar, who doesn’t have much to say that’s interesting, and whose name you can’t recall when you meet him again.

But any local fisherman will tell you that without the mangroves, the sea would be barren, devoid of fish, crabs, lobsters and prawns – and thus of all the species higher up in the food chain. Mangroves are the nurseries for many of the reef species. Reef fish and other animals lay their eggs among the mangroves. The hatchlings are washed out to sea by the floods in the rainy season. Those that make it to the reefs get a chance at life.

The mangrove forests are also the permanent habitat for many species, with crab-eating macaques – a rowdy, curious species of monkey – being top of the chain.

Trees really shouldn’t survive in sea water – there’s too much salt. But mangroves have adapted to this marginal niche that no other tree would consider. The tangled stilt roots of the world’s mangrove forests form a massive desalination plant unrivaled by man. By the time the sea water gets into the trunk of the tree, 97 percent of the salt has been extracted. Some trees excrete it through their leaves. Others have rootlets that stick into the air, through which the salt is squeezed out.

They can also limit the amount of precious fresh water lost to the air. They can vary the size of the pores in their leaves and can orient their leaves to reduce the sunlight hitting the surface. They may not look too exciting, but these are very special plants.

The weird stilt roots of the mangroves.

By colonizing silty coastlines, they create new land. So while most of the west coast of Phuket is being slowly eroded by the annual monsoon storms from the southwest, the mangroves are slowly extending the east side. Phuket, in effect, is gradually moving east.

They also form a protective barrier. After the 2004 Asian Tsunami, it was noted that communities behind mangrove forests suffered less damage than those that were not protected.

Kayak tours of the mangroves can be booked though John Gray’s Seacanoe, or PaddleAsia, or by electric boat with River Rovers.