Reviving the Green Guardians: The Imperative of Seagrass Conservation

 

Reviving the Green Guardians: The Imperative of Seagrass Conservation

By Attish Kanhai, Research Officer

Institute of Marine Affairs

 

Pastos marinos in Spanish, Herbiers marins in French, Lamun in Indonesian, Nyasi bahari in Swahili or Seagrasses in English. The different names of seagrass meadows worldwide reflect their importance in the tourism industry, recreational activities, and for spiritual and religious purposes. Specific names in local languages reflect the value of these ecosystems; for example, the name Lamun is particular to the Indonesians, evidence of their acknowledgment of seagrasses in their culture, similarly the name Nyasi bahari in Swahili. Some cultures take it even further. The Monken tribes from the Myeik Archipelago in Myanmar refer to seagrasses as Leik-Sar-Phat-Myet or “the food of marine turtles.” Much simpler for us here in Trinidad, Thalassia testudinum is commonly known as turtle grass and Syringodium filiforme is known as manatee grass.

 

Other cultures take into account the reproductive ecology of these vital ecosystems. The Seri, an indigenous group in Mexico, refer to the month of April as xnoois ihaat ilzax or, “the month when the seagrass flowers”. Other cultures, such as the fishers of the Solomon Islands, view seagrasses as lucky charms and twist the leaves together as a lucky ritual. Seagrasses may have something in common with four-leaf clovers, after all! Seagrasses do have some more tangible benefits, however.

 

Seagrass form habitats that support an amazing array of plants and animals. Crustacean and fish abundances are seven to twenty times higher in seagrass meadows compared to adjacent bare sand areas. Many commercially important species, such as fish and lobsters, rely on seagrass meadows as nurseries and foraging grounds. Seagrasses provide habitats for fish species that support the sport fishing industry, such as tarpon, bonefish, and snook, while providing food sources for green turtles and manatees, which are popular tourist attractions. In temperate climates, popular bird-watching species such as the brant geese are found in the seagrass meadows in the United Kingdom and the United States.

 

Despite all this cultural, economic, and intangible significance, the story of seagrasses remains dire. Seagrasses are among the most threatened ecosystems globally, disappearing at an annual rate of 7 percent per year, equivalent to a football field of seagrass every 30 minutes. As of 2022, only 95 hectares of seagrass meadows are left in southwest Tobago.

 Restoration schemes have become a necessity to address this alarming rate of loss.

The Institute of Marine Affairs (IMA) is currently engaged in a rehabilitation project to restore degraded seagrass habitats in Tobago as part of its Marine Resilience Initiative (Project MARIN).

 

The IMA will trial different methodologies to ascertain the best fit for seagrass replanting, as it is not as simple as putting new shoots or seeds into the seabed and expecting them to grow. Other factors such as water clarity, current and wave action, and nutrient concentrations in the coastal environment must be considered for a replanting project to be successful. It is also recommended that seagrasses be replanted in areas where they once existed. Factors, however, that contribute to their disappearance in the first place, such as land-based sources of pollution, must also be addressed.

Seagrasses also need to be managed effectively during coastal developments, and bold steps must be taken to ensure the recovery and restoration of these habitats in areas where losses have occurred or are likely to occur. Once these ecosystems are lost, they are challenging to recover. It is therefore imperative that any coastal and inland developmental projects are planned and executed in such a way that there are little to no harmful impacts on seagrass beds. As the adage goes, prevention is better than cure; in environmental terms, preservation is better than restoration.  It is essential that economic, and infrastructure development happen in tandem with ecological enhancement and preservation.  The environment and the services provided are as relevant now as they have always been and so shall it remain in the future.

World Seagrass Day, commemorated on March 1, is an opportunity to reflect on the many benefits derived from these precious ecosystems and the way our own actions, both small and large scale, facilitate or detract from these benefits. This article does not represent an exhaustive list of the benefits derived from seagrasses as they are too numerous to list in a few words, but we can hope that through careful and thoughtful development, consideration and education, seagrasses can once again flourish, regardless of the names by which they are called.