Environment Ministry Launches Programme to Stem Coastal Zone Erosion

Minister of Environment the Hon. Earl Deveaux shows the plants native to The Bahamas. The Ministry is planting native trees to replace invasive plant species at the Western Esplanade to help stem the erosion of coastal zones. (BIS photo/Letisha Henderso

NASSAU, Bahamas -- The Ministry of the Environment is spearheading a programme to stem the erosion of coastal areas by ridding the country of invasive plants not native to The Bahamas such as casaurina and Hawaiian sea grape (scaevola).

Minister of the Environment the Hon. Earl Deveaux said in a recent interview that many people tend to grow these invasive plants around their homes because they look good and grow quickly in virtually any type of environment.

But the Minister pointed out that these plants destroy the country’s native trees and dominate the environment. The plants, he said, are also destroying the sand dunes and their vegetation that protect the islands of The Bahamas from beach erosion.

To counteract such erosion, the Ministry is launching an initiative to encourage Bahamians to grow native plants and to aid in efforts to remove the invasive plants.

The Ministry has commenced landscaping public areas particularly near the beaches with native plants. Residents of Orange Hill have taken the initiative to plant native trees to rebuild the sand dunes in their area.

Environmental Educator at the Bahamas Environment Educational Foundation (BREEF) Charlene Carey said the plants native to our islands include: sea oats, sea purslane, coco plums, railroad vine, sea grapes, buttonwood, bay lavender, bay lilies, bay geranium. There is also a native scaevola.

Mrs. Carey said small island countries that often have a unique bio-diversity are particularly vulnerable to destruction from invasive species. She explained that all of the small islands’ ecosystems work together to protect them from erosion.

Mrs. Carey added that coral reefs break up large ocean waves creating calmer seas between the reefs and the shoreline.

“If we were to damage the reef then those big waves would come onshore and we would have more beach erosion, which is not good for tourism and certainly not good for us in terms of housing and storm protection.”

She added, “In a storm though, the waves are still big enough to get past the reef. So the beach dune is what will protect us from the water going further inland.

“The big waves from the storm will come, hit the beach, and go back and then any sand that it takes with it as it goes is going to get trapped by the sea grass.”

Mrs. Carey explained that the sea grass helps to trap the sediment in the water and keep it beachside where it will eventually get pushed onto the beach. Thus the three ecosystems: the coral reefs, the sand dunes and the sea grass, all help to maintain the beaches.

The needles from the casuarina plants, however, form a thick blanket that blocks the sun so that nothing grows underneath them, she noted. The needles also produce a toxin that prevents the growth of native plants.

Pointing out that the invasive casaurina plant has a shallow root system, Mrs. Carey said, “So as waves come up with the storm it washes the sand from under them and they fall over and take the balance of the sand with them and then you have lost your dune.”

Executive Director of BREEF Casaurina McKinney added that invasive species do not have natural predators because insects do not eat them as no insect has evolved with the plants.

However, Ms. McKinney said some balance is needed in an ecosystem where plants are eaten by animals. “If you have a plant that no animal is eating, you are throwing nature out of whack.”

She suggested that a new industry could be built up around the casaurina as the country tries to rid itself of the plant, noting that the bark can be used as charcoal and exported since it is very popular with users of outside grills.