BLACK RIVER, St Elizabeth — The problem is not yet at crisis proportions, but scientists are voicing increasing concern at the invasion of alien plant species in the ecologically priceless Black River Lower Morass.

Alpinia Allughas, colloquially referred to as wild ginger, and the Australian paperbark tree, which carries the scientific name Melaleuca Quinquenervia, are the species attracting the most attention.

According to Dr Kurt McLaren, senior lecturer, Department of Life Sciences, University of the West Indies such “invasives” have the potential to destroy the ecology of the Black River Morass.

Seen as a “natural sponge” crucial to soaking up excess water and mitigating flooding on the St Elizabeth plains, the 15,600-hectare Black River Lower Morass is classified and protected under the Ramsar Convention. Signed in Ramsar, Iran, in 1971, the convention provides for the conservation and sustainable use of important wetlands.

The lower morass is also of direct economic importance, partly because of its plentiful fish and shrimp, but increasingly for its attractiveness to tourists.

On a daily basis, many boatloads of tourists travel up and down the Black River to experience the largest freshwater wetland in Jamaica and the islands of the English-speaking Caribbean.

The Black River is home to the famed American crocodile and numerous species of endemic birds and plants.

As part of the four-year project dubbed Mitigating the Threats of Invasive Alien Species in the Insular Caribbean (MTIASIC), now at its end stage, the National Environment and Planning Agency (NEPA) recently took journalists two miles up the Black River to see plant invasions at first hand.

Funded by the Global Environment Facility (GEF), the United Nations Environment Programme and the Centre for Agriculture Bioscience International (CABI), the project embraced pilot projects aimed not only at the paper bark tree and wild ginger, but also other invasives including lionfish and predators which target the Jamaican iguana.

Pleasing to look at, with its cute pink flowers, but also deadly to fresh, innocent environs, the alpinia (wild ginger) is a member of the ginger family and originally came to Jamaica as an ornamental. Its origins are in South East Asia. It has spread fast across the lower morass taking up one per cent of the wetlands, according to estimates.

Experts say it is difficult to control because it spreads both by root and its flowered seeds. And once the thick clusters take over an area all other plants die. “Wild ginger rapidly displaces other plant species… it grows in very dense thickets, and so whatever else was growing there is smothered,” explained NEPA’s Nelsa English Johnson.

McLaren, who has been observing and researching the lower morass at close quarters since 2004 and has headed efforts at control with help from MTIASIC project and sometimes “out of my own pocket”, says eliminating wild ginger doesn’t seem feasible. “The best bet is control”, he said.

Experiments carried out under the MTIASIC project as well as information from elsewhere suggest that the best control method is to frustrate growth by persistently cutting away at its roots and leafage. Replanting with native species to further frustrate the invasive is also recommended.

Happily for McLaren, the MTIASIC project has provided a kind of “industrial-sized lawn mower” specially designed for wetlands which he believes will be invaluable in wild ginger control measures.

The paperbark tree, originally from Australia, has become a problem for wetlands across the globe. In the huge Florida Everglades it is a horror story, taking over much of that world-famous wetland. It is said to be costing the US authorities in excess of US$160 million annually in environmental damage.

Yet, according to McLaren, while expanding fast in the lower morass, the paperbark tree — which may also have been taken to Jamaica as an ornamental — is still at the stage where it can be eliminated with determined action. That’s virtually unheard of for plant invasives in Jamaica.

“It’s less than a thousand trees,” explained McLaren. “So you can actually go and remove all of those trees. In my lifetime I have never seen anything (invasive plant species) that you can actually (remove completely),” said McLaren.

But such action will have to happen quickly since the tree which can grow to height of up to 100 feet, grows fast and reproduces quickly. Like other aggressive invasive species such as the wild ginger, the paperbark tree displaces all other plants.

Each mature tree has millions of seeds which quickly cascade from pods whenever the tree comes under physical threat.

It is fire resistant, recovering very quickly from conflagrations, yet its flaky bark also makes it highly flammable and is said to have helped to fuel massive fires in the Everglades.

The trees use up large amounts of water and, according to McLaren, “can cause problems with the whole hydrology of the morass and it could affect the availability of water… If you have this thing establishing itself you probably won’t have a morass much longer…”

A combination of chemical use and careful cutting has been used to control the paperbark tree. Also, according to McLaren, a traditional method of cutting away the bark of the tree to get to the delicate tissues below can help to facilitate quick eradication.

All agree that as the MTIASIC project — which provided US$749,000 with matching resources in cash and kind from the Jamaican government — comes to an end, finding the money to continue fighting invasives present a major challenge.

But for English Johnson, the hope is that a public education programme in the St Elizabeth capital, Black River, and other communities surrounding the lower morass will have made a difference in how residents treat invasives and seek to protect their environment.

Social interventions using sports and community activities have been invaluable, she says. An interpretive art display, entitled Black River’s Treasures, sited at Charles Swaby’s South Coast Safari headquarters at the mouth of the Black River just east of the town centre is central to the programme which encourages the notion that protecting Black River’s biodiversity will preserve the community’s legacy.

The bottom line, says English Johnson, is that people not only in Black River and the wider St Elizabeth, but across Jamaica, are being encouraged to stop moving “living things (in the wild) from one place to another”.

“Take a picture; a picture will last forever. Leave living things in their living habitat,” she said.