In April 2024, Research Assistants, Andrew and Simone, went on a field trip to two sites in Tobago to observe the mangroves as the project team prepares to model them in the laboratory. Mangroves in Trinidad and Tobago fall within the Amazon-Orinoco-Maranhao mangrove complex in the Orinoco bioregion. According to Juman and Hassanali (2013), mangroves cover approximately 2km2 of land in Tobago. Four species of mangroves are found in Tobago: Rhizophora mangle (red mangrove), Laguncularia racemosa (white mangrove), Avicennia germinans (black mangrove) and Conocarpus erectus (buttonwood mangrove). 

 

Satellite view of mangroves along the coastline at Little Rockly Bay

Satellite view of mangroves along the coastline at Petit Trou

 

Observations took place at Petit Trou, where there is a boardwalk for recreational activity, and Little Rockly Bay (Lambeau). Red mangroves were predominantly visible at Petit Trou, and red, white and black were observed at Little Rockly Bay. There were several areas of dieback at both sites, presumably due to pollution and sediment accumulation. Where dieback of red mangroves was observed at Little Rockly Bay, white mangroves were observed to be establishing themselves. In addition, the impacts of the diesel spill that took place in February 2024 were also observed at both sites.

Red Mangroves on either side of the boardwalk
Impacts of the February 2024 diesel spill (in black) observed on the roots of mangroves. Die back of mangroves is also evident here, presumably related to the incident
Another view of the mangroves at the boardwalk in Petit Trou

 

The island’s economy relies heavily on the coastal ecosystems present; over 80% of economic activity is situated in the coastal zone. Mangroves within the Buccoo Reef-Bon Accord Lagoon Complex are protected under the Marine Areas (Restricted Area) Order of the Marine Area (Preservation and Enhancement) Act of 1970. This area is also a designated Ramsar site. The other mangrove forests located at Petit Trou, Friendship, Little Rockly Bay and Kilgwyn are unprotected. Despite legislative protection and the importance of mangroves to the island’s economy, mangroves have been and continue to be impacted by human activities, specifically land clearing and pollution, leaving them susceptible to decline and disappearance.

Special thanks to Howard Robin at the Tobago House of Assembly’s Coastal Zone Management Unit for accompanying and assisting us on the trip.

 

Reference:

Juman, Rahanna, and Kahlil Hassanali. “Mangrove Conservation in Trinidad and Tobago, West Indies.” Mangrove Ecosystems: Biogeography, Genetic Diversity and Conservation Strategies (2013).