Scientists find rare species of mangrove in the Philippines

Yolanda Sotelo-Fuertes, Philippines Inquirer 14 Apr 08;

DAGUPAN CITY—Scientists have found a rare species of mangrove in what they described as a unique environmental setting in Masinloc, Zambales.

“It’s a hybrid mangrove called Rhizophora x lamarckii produced by ‘bakauan lalaki’ (Rhizophora apiculata) and ‘bakauan bato’ (Rhyzophora stylosa),” Severino Salmo, a mangrove researcher, told the Inquirer.

Salmo, who is pursuing a doctoral degree in marine science at the University of Queensland in Australia, said the species was so rare that there was only one tree found on Panay Island in Eastern Visayas.

He and his professor, Dr. Norman Duke, are studying the restoration of mangrove ecology in the Philippines and Australia. Duke is a principal research fellow of the University of Queensland’s Center for Marine Studies.

Salmo said he and Duke found 12 trees of the mangrove species (it has no local name yet) in a five-hectare mangrove-formed island (where no other vegetation except mangroves are found) called Yaha by Masinloc residents.

The island is some 5 kilometers from the mainland. From afar, it seems to be a pure stand of bakauan lalaki and bakauan bato, according to Salmo.

“Doctor Duke, however, noticed one mangrove towering over other trees. At closer look, the leaves are greener. Upon collecting specimens and evaluating its flowers, he confirmed that it was a mangrove hybrid called Rhizophora x lamarckii produced by bakauan lalaki and bakauan bato,” Salmo said.

He said he and Duke found only a single tree of the species on Panay Island. In Masinloc, however, they saw at least 12 trees. The species can be found in other countries, like India, but it is also rare there, Salmo said.

Protect parent plants

The newly discovered mangrove species has an average diameter of 5.5 centimeters and height of six meters.

“The findings can be considered the first record of such species in Luzon. As hybrids are sterile, they cannot reproduce. The only way to conserve it is to protect the population of its parent plants,” Salmo said.

He said local officials and the community were not aware of the existence of the rare species in their midst.

“We informed Masinloc Mayor Jessu Edora about it and he said the local government would declare the site a marine protected area. He also ordered an immediate patrol in the area,” Salmo said.

The two researchers were looking for study sites to compare natural and planted mangroves when they found in Masinloc a natural mangrove area with environmental characteristics similar to those found in Lingayen Gulf. They found Yaha with the help of local officials and fishermen.

“It was difficult to find natural sites as most, if not all, areas have been severely disturbed or degraded. Natural mangroves in the Philippines are very rare now given the massive cutting and conversion to aquaculture ponds. The Philippines already lost 70 to 80 percent of its natural mangroves,” Salmo said.

Special place

Yaha can be considered a special place and is different from other mangroves because it is located in a natural environment where mangroves developed over a long period, the researcher said. While there were some observed cuttings and encroachments, the area can still be considered relatively undisturbed, he said.

“It is being used by locals as a docking place when they go fishing. The surrounding water is a rich fishing ground for small fishermen,” Salmo said.

He said older residents in Masinloc told him that the mangrove-formed island had been there for at least 80 years. It also served as a hiding place for Filipino soldiers during World War II, he said.

The study, which Salmo and Duke are undertaking, aims to understand the environmental impact of mangrove areas converted to other uses. They also want to find out how long planted mangroves would resemble the forest structure of natural mangroves.

Salmo said the study would give conservationists and environmental managers a “realistic idea” of how much mangrove planting projects can achieve over a certain period.

The study is timely, considering the extent of mangrove cutting in the country and the various efforts at rehabilitating mangrove areas through massive planting projects, he said. Its sites for the planted mangroves have been designated in the western part of Lingayen Gulf, covering the towns of Bolinao, Anda and Bani and Alaminos City, where Salmo spent 12 years of research.