On the way to Polillo town from Burdeos, I noticed the national road had many parts of it paved in concrete than ever before. Some years back, it was all dirt road and you could just imagine the difficulty getting from one town to the other, especially when it rained. Some sections were still left unpaved, but it was a sign of improvement no matter how slow the pace was.
It was just last week that I had an opportunity again to visit the Polillo Islands to implement a project on mapping mangroves using radar imagery. We had collected field data from several barangays around Burdeos to enable us to interpret the ALOS/PALSAR data and map mangroves and detect changes over time. We also facilitated a participatory mapping exercise with local stakeholders to map changes in the extent of mangroves based on their knowledge.
Before this activity, the last field survey I did in the Polillos was in 2006 to produce a land cover map of the island in support of managing priority conservation areas for biodiversity. I used an optical Landsat 7 ETM+ image acquired in 2001 to map remaining forest habitats and other land cover features, and went off to collect field data as well for interpreting the image. Finding a Landsat image devoid of clouds was rare in many parts of the Philippines and especially in areas such as the Polillos, so I felt truly lucky having found a rare archived picture of the islands taken from space almost clear of cloud cover. In fact, only about 1% of the entire Polillo archipelago is covered with clouds in the image below.
I stretched the color values of the image to enhance the contrast and to highlight land cover features, especially forests. In the main island of Polillo, forests stand out from the image as dark green pixels surrounded by bright green areas, which can be located at the southern, central, and northern portions. Other forest patches are found in the nearby island of Patnanungan, the second largest island next to Polillo. Forests shown in this 2001 snapshot are rather patches instead of large extensive forest blocks. A participatory 3D map of the Polillo islands was produced during the 1999-2001 joint Polillo Project of Oxford University and University of the Philippines Los Banos, which complements the Landsat image acquired within that period (see image below) .
I wanted to get my hands on old published maps showing how the forests of the Polillos looked like back in the day for lack of any available historical Landsat imagery taken between the 1980s to 90s to see what changes may have occurred. But I have not been fortunate to find this map yet. The closest I could get to were the published writings of Dr C Robinson and Mr R McGregor in the Philippine Journal of Science describing the forests of the Polillos during their expeditions in the early 1900s. Fortunately, electronic copies of the Philippine Journal of Science are archived at the Biodiversity Heritage Library and the Flora of the Philippines Library.
In R McGregor’s “Birds Collected in the Island of Polillo, Philippine Islands” published in 1910 in the Philippine Journal of Science (vol.5, no. 2), he described Polillo’s forests as :
Although nearly the entire island is mountainous, no part of the surface has a great elevation, the highest point, Mount Malulud in the north-central part, being but 350 meters. With the exception of a few small areas planted with rice, mostly along the western coast, Polillo is heavily forested. No grass land was discovered and in no island have I seen so large a proportion of the area covered with trees.
Then, in C Robinson’s “Botanical Notes Upon the Island of Polillo” published in the succeeding year on the same journal (vol.6, no.3), he described the forests of the Polillos as :
Except for cultivated land, Polillo is nearly everywhere covered with virgin forest, waste land being of very slight extent.
While these statements do not show the extent of forests back in the early 1900s as explicitly on a map, it provides the only known empirical observations of the forests at that time. If we trust that these scientists accurately described what they actually saw (and we can) and left no room for exaggeration, then we could at least imagine the forests of the Polillos as if on a map covering almost every inch of the islands.
Nine decades, more or less, after the published accounts of McGregor and Robinson, the 2001 Landsat image presented a different picture of forests that were almost on the brink of being wiped out. Even local knowledge at the time the 3D map was drawn and produced has shown how original forests have shrunk until only forest patches were left. While other features of the island such as roads have shown signs of improvement, forests however have declined over this period.
Perhaps it is comforting to know then that there are on-going efforts by local governments and organisations such as the Polillo Islands Biodiversity Conservation Foundation and the Katala Foundation to conserve the last remaining forests and important biodiversity of the Polillo archipelago, which are hopefully not too late.
 Polillo Project: Final Report. 2001. (http://polillo.mampam.com/Summarypage.htm) accessed 10 August 2014.
 McGregor, R. 1910. Birds Collected in the Island of Polillo, Philippine Islands. Philippine Journal of Science, 5(2):103-114.
 Robinson, C.B. 1911. Botanical Notes Upon the Island of Polillo. Philippine Journal of Science, 6(3):185-228.