There are two proven ways to get a fresh water pond in Bermuda: one, put down concrete and a liner and then turn on the garden hose, or alternatively, wait several thousand years for peat to form in a basin of land.

It's for that reason that the few natural freshwater ponds Bermuda has left are so important.

The Royal Gazette recently spoke with Dr. Martin Thomas, author of 'A Natural History of Bermuda' about Bermuda's ponds. Ecologist Dr. Thomas is Professor Emeritus at the University of New Brunswick in Canada and has been bringing students to the island to study Bermuda's ecosystem for decades. Ponds are one of his passions.

"Compared to anywhere else you have almost no fresh water habitats," said Dr. Thomas. "One reason is that it is a very small island and a lot of the land falls close to sea level so you get a lot of salt in ponds, so fresh water ponds are really rare here. There were more and we have lost more than half of them, which is a shame because they are home to hundreds of things including birds and animals."

One of the problems about fresh water ponds is that they can be hard to define. For example, Spittal Pond in Smith's Parish can be almost entirely fresh at certain times of the year, and at other times, almost entirely salt water.

"Seymour's Pond in Southampton is one of Bermuda's last remaining fresh water ponds," said Dr. Thomas. "The big freshwater ponds were historically in Devonshire Marsh and Pembroke Marsh. Pembroke Marsh was the biggest in Bermuda. It was huge. It was east of Hamilton all the way to Mills Creek. Pembroke Marsh East is where the old trash dump was and Pembroke Marsh is where the industrial park is now. It had the only estuary in Bermuda."

It seems hard to believe that once Bermudians boated on the estuary and hunted birds there. Every year a large number of eels swam up the estuary. Today, that estuary has been reduced to a slimy, toxic drainage ditch known as Mills Creek.

"A lot of people think that Warwick Pond is fresh, but it isn't," said Dr. Thomas. "It actually has about 80 percent fresh water and ten percent sea water. We know it has never been fresh, because it is home to the Bermuda killifish which is unique to Bermuda. These fish can't live in fresh water and they need a few thousand years to change to a new species. So that tells us that Warwick Pond has been a semi-marine pond for thousands of years. People think that what is in Warwick Pond might be a distinct species of killifish. That is just one example of the interesting things you can find in Bermuda's ponds."

Along with the Bermuda Zoological Society, Dr. Thomas plans to write a technical report on the ponds to chart various characteristics including size, history, and flora and fauna, among other things.

"Legislative protection is okay, but that is not all you need," said Dr. Thomas. "The problem with the ponds is that they're ponds. They are all in low lying areas. A farm a quarter of a mile away puts some herbicide on their weeds, it rains and it runs into the pond. No amount of legislation could stop that short of banning herbicides, and that probably would never be done in our lifetime. So ponds are natural sinks for anything. It could be good stuff, food for the fish, and it could be a little bit of nitrogen phosphorous which helps the plants to grow, but at the same time it could be heavy metals and organic pesticides. They all finish up in the ponds. "Fortunately, the animals and plants that live in the ponds are very tough. Some of them look so delicate you would think the slightest upset in their water or environment would clobber them, but it doesn't."

The ponds are also often strongly resistant to bad weather. After Hurricane Fabian ponds such as Walsingham pond, bounced right back.

"It was a disgusting mess right after the hurricane," said Dr. Thomas. "It was cleaned out and in three months you wouldn't have known anything happened. It has the capacity to recover."