All Philippine islands when Ferdinand Magellan arrived in the country in the mid 16th century were, in general, thickly clothed with mixtures in various proportions of mangrove forest, beach forest, tropical rainforest, monsoon forest, hardwood forest, and other forest types probably by as much as 90 percent of their area cover.
Thousands of higher plant species were found in these forests.
The marine and fresh water ecosystems extant today may be assumed to harbor all the approximately 2,500 species of fish, the 27 species of marine mammals and other aquatic vertebrates, and the thousands of invertebrate species we see today.
Likewise, the land can also be assumed to be teeming with some 1,100 species (and still counting) of terrestrial vertebrates that are known to be present today in the various microhabitats in the forests.
Magellan and his men also found people living on the islands they landed to claim them as part of the territory of Spain.
Unfortunately, he met strong resistance by a group of Filipinos living on the island of Mactan led by the man we now call Lapulapu.
In the ensuing battle along the coast of Mactan fringed with mangrove and coral reef, Magellan and some of his men were killed.
Later, Filipino leaders erected a monument in honor of Magellan. But I am told that the monument to honor Lapulapu was erected much later!
What is described in the first paragraph is the most likely picture of Philippine islands 500 years ago, which can be considered as a pristine environment.
Mactan Island, a part of the larger Cebu Island in the past, was probably not too different from Cebu or Negros, both of which used to form a single island in the past.
Actual surveys on land vertebrates in the mid-1900s showed a depauperate vertebrate fauna on Mactan as compared with Cebu or Negros.
It can be inferred that various forest microhabitats on Mactan in the past had similar fauna and flora as Cebu and Negros, many of which have been lost in the course of time.
But as can be seen now, it lacks the species diversity of ecosystems and associated biological components, although a part of its marine ecosystem, namely few coral reefs, continue to exist and are to a very limited extent a tourist destination.
But the mangroves have been reduced to stunted forms, and seem unable to develop into the climax status, probably because of the altered environmental conditions.
The island’s poor biodiversity is indicated by fewer fish fauna and fewer terrestrial vertebrate species. It is, however, considered a developed human community with a large number of people residing on it.
But the people have to pay a high price in that no potable water exists on the island, and drinking water has to be brought in from outside sources.
The large human population is probably the reason for the presence of chemical pollutants, notably from waste water and toilets, in its coastal waters.
The whole island has been altered from what it used to be hundreds of years ago.
From Mactan, we move to the remote island of Siargao situated in the Pacific Ocean. Siargao, like many islands formed by volcanic action several million years ago, is primarily made of limestone and has thin top soil that is not productive for farming purposes, but rainforests and mangroves are well developed.
Rainforests were logged for their commercial tree species, including the lauan group or Philippine mahogany and the iron wood.
Areas from where these trees have been removed are now occupied by coconut trees, most of which are doing poorly and are non-productive.
However, the remaining forest estimated at about 20 percent of the island’s land area still hosts some biodiversity species unique to Siargao, notably the Indo-Pacific Crocodile, and a yet unnamed species of forest frog.
A thorough survey of the rainforest and the mangroves would probably yield more new forms of life.
In the marine waters of Siargao are rare deep-sea fish species not common to other Philippine islands. All these are valuable resources that can be used in a sustainable manner to benefit the people of Siargao.
Despite the disappearance of some of its original flora and fauna due to past exploitation, Siargao still retains some of its pristine character. But these features may eventually be lost over time if conservation measures are not put in place soon. If these measures are not implemented soon, Siargao will surely go the way of many Philippine islands that have lost their uniqueness, and are now biological deserts.
Siargao has been proclaimed part of the Philippine national protected areas system since 1996, but this does seem to be working well, as indicated by many violations of this proclamation.
The island’s human population is expanding rapidly. Very soon, people will need places on which to build their homes.
Zoning of the island into protected areas and areas for human habitation is therefore in order.
In this regard, both the nine local government units (which need to act as a unit in the governance of the whole island) and the national government through the Protected Areas & Wildlife Bureau of the Department of Environment & Natural Resources should be involved in the zoning.
There is also a need to manage or control the rate of human population growth on the island, a primary concern of the LGUs. This is possible with the advent of family planning technology.
The coastal zone of the island should be given urgent attention. Many resorts have sprouted along the shoreline, and most of them have ignored DENR guidelines on building infrastructures on beaches. This is necessary in view of the rising sea level of the Pacific Ocean as a result of climate change.
In summary, for Siargao to avoid going the way of other small Philippine islands that have lost their unique environmental features and biodiversity resources, local governments and the national government should ensure that its natural resources are conserved and managed well to provide for food security and income of the people.
Tourism with proper safeguards should be given attention. LGUs should continue to improve facilities and infrastructures such as hospitals, schools, and road system of the island.
Urgent measures to slow down the rate of population growth should be implemented as the island soil is too poor to support a large population in terms of agricultural products.