Philippine crocodiles are amongst the most endangered of the freshwater crocodiles. Small, with relatively broad snouts, on their backs they have thick bony plates. They have between 66 and 68 teeth which regularly fall out, to be replaced by new ones. Their golden brown color darkens as they grow. The females are a little smaller than males. This critically endangered species was once common throughout the Philippines but today lives on only a few islands.
Philippine crocodiles are historically indigenous throughout the islands of the Philippines, including Dalupiri, Luzon, Mindoro, Samar, Jolo, Masbate, Negros, Busuanga and Mindanao. It is now limited to the north of Luzon and the southwest of the Mindanao islands. This species makes its home on estuarine and coastal shores. Most of their habitat is in freshwater areas and may include ponds, marshes and small rivers.
Philippines crocodiles rest in the sun during the day to warm up. When they are too hot they will open their mouth to release heat. These crocodiles are able to float on the water’s surface. To control their buoyancy they will ingest stones. Not much is known about perception or communication in Philippines crocodiles. In general, crocodilians' skin color changes depending on their mood or the environment. In addition, their bright yellow or orange tongue in their gaping jaw may act as a social or warning sign.
The mating system of Philippines crocodiles is unknown. However, crocodiles are polygynous, which means that a single male mates with a number of females. Courtship and mating take place from December to May during the dry season, and eggs are laid from April to August, with a peak in May or June at the start of the rainy season. Philippine crocodiles will lay a second clutch after 4 - 6 months, and may lay as many as three clutches each year. Clutch sizes range from 7 - 33 eggs. In the wild, the incubation period is 65 - 78 days, while in captivity it is 77 - 85 days. Females build a mound nest from leaves, twigs and soil or they make a hole nest, in which to conceal their eggs. Once the eggs are laid, males and females both take turns watching the nest, and females routinely visit the nest either early morning or late afternoon. Females become mature at 10 years of age, while males become mature at 15 years of age.
The huge population decline of this species in the past was due to excessive hunting for commercial use. Today, destruction of their habitat is the most serious threat to its survival, as rainforests are cleared throughout the region for rice fields to feed the increasing human population. The infamous 'saltwater' or estuarine crocodile, one of the world’s largest, with a reputation for being a man-eater, lives in the same area and undoubtedly contributes to intolerance by locals of any crocodile species, so the small Philippine crocodile is also often killed when encountered.
According to the IUCN Red List, the total Philippine crocodile population size is around 92-137 mature individuals. Currently this species is classified as Critically Endangered (CR) and its numbers today are decreasing.