Countries all over the world will mark Cetacean Day on Wednesday.

The order cetacea includes whales, dolphins and porpoises. It is derived from the Latin word cetus, meaning whale.

Cetacea are one of the most distinctive and highly specialised orders of mammal. They have a fusiform body, making it easier for them to be fast swimmers. Through evolution their front limbs transformed into flippers and their hind limbs do not attach to the backbone and are hidden within the body.

Unlike fish cetaceans have horizontal tails known as flukes. To keep their temperature constant, their body is insulated with a thick layer of fat called blubber.

There are around 86 species of cetacea, 21 of them found in the Mediterranean and Black Sea.

In Malta, marine mammals are protected by Resolution 2003 which states that: "No person shall, directly or indirectly, pursue, take or attempt to take, maltreat or attempt to maltreat, kill or attempt to kill, possess, sell by any method, buy, exchange, re-introduce, import or export any specimen of species listed in the Schedule to these regulations".

Drift nets and long lines as well as shark safety nets catch many cetaceans.

Another activity posing a threat to dolphins and whales is the dolphinarium where dolphins are literally kidnapped from their natural habitat.

Dolphins travel long distances and live in tightly-knit social groups and extensions of families. Removing them from this social network inflicts stress, which can be fatal. Dolphins are made to perform and are trained to behave unnaturally, being fed by humans.

Nature Trust (Malta) promotes dolphin awareness. It supports the anti-captivity campaign and has its own professional rescue team on call 24 hours a day. The team also keeps record of mammals and turtles washed up dead. There are around seven to 10 reported beached or stranded dolphins, whales and turtles each year.

Nature Trust is also involved in Operation Delphis, set up in France in 1996. Boaters from different Mediterranean countries go out to sea to collect data on cetaceans, turtles and plankton levels by taking water samples for analysis.

As part of its on-going public awareness campaign, Nature Trust, together with Eden Century Cinemas, will be hosting a screening of the Oscar-winning film The Cove (Best Documentary of 2009), on April 27 at 6.30 p.m. The powerful, influential film highlights the suffering of dolphins captured from the wild.

Free tickets will be available at the box office; however, donations to Nature Trust (Malta) for the Wildlife Rehabilitation Centre project will be appreciated.

For more information e-mail info@naturetrustmalta.org or visit www.naturetrustmalta.org.