There are a number of different rainforest formations present in the Peta side of Endau-Rompin, formed as a result of soil or elevation. The most extensive of these is the lowland dipterocarp forest. Dominated by towering trees of the Dipterocarpaceae family, this forest is among the most species-rich terrestrial ecosystems on earth.
Some of the best Heath forests is Peninsular Malaysia occur on the shallow, sandy soils of the park’s sandstone plateaus. This forest type contains low-statured, small-crowned trees and plants that are able to survive in the nutrient-poor environment, including carnivorous pitcher plants as well as epiphytic ant-plants.
A form of heath forest known as Padang vegetation is found on the swampy parts of the plateaus where drainage is poor. These open habitats, which are typified by sedges, orchids, club mosses and giant screw-pines, are more typical of Sarawak than Peninsular Malaysia.
Fan palm forests present on the margins of the plateaus are composed almost exclusively of a single species – the Endau fan palm that also adorns the logo of Johor Parks. The best place to see this unique forest is at Janing Barat, which can be reached from Kuala Jasin.
Riparian habitats alongside the park’s rivers possess a distinct plant community rich in herbaceous and epiphytic plants. The River Tristania or Pelawan, a relative of the Australian gum tree is one of the most recognizable trees here with its beautiful grey-white peeling bark. Semi-aquatic plants known as rheophytes occupy the mist-laden areas around waterfalls, the banks of fast-flowing streams and rocky islands on the rivers. These rheophytes, such as the hyper-endemic Phyllanthus watsonii and the pretty fern Dipteris lobbiana have pliable stems, strong root systems and other physiological adaptations to withstand strong currents and periods of inundation.
Being the largest protected area in southern Peninsular Malaysia, the park plays a key role in the conservation of globally-threatened large mammals, including the Malayan Tiger, Asian Elephant, Malayan Tapir and Sunbear. The tiger’s preferred source of nourishment, the Sambar deer is present in the park, together with the barking deer and two species of mousedeer – the smallest hoofed animals in the world.
Johor is the only part of the peninsula where populations of the Bearded Pig still persist. This species is larger, lighter in color and reputedly less aggressive than the more widespread Eurasian Wild Pig.
Monkeys are represented in the park by the Long-tailed and Pig-tailed macaques plus two species of langurs. The more often seen Dusky Langur is distinguished by the spectacle-like rings around its eyes, whereas the Banded Langur has black fur with white bands on the underside of its body and limbs.
The park is also an important habitat for a few other globally-threatened mammals such as the Sunda Pangolin, White-handed Gibbon and Sunda Slow Loris, as well as many other smaller mammals including civets, squirrels and treeshrews.
The park, together with the adjacent Endau-Rompin State Park in Pahang was listed as an Important Bird & Biodiversity Area (IBA) in 2003 by BirdLife International. At least ten globally-threatened birds have been recorded in the IBA, including the Helmeted Hornbill and Straw-headed Bulbul.
Over 100 species of fish have been recorded in the park; the most abundant being the cyprinids, loaches and catfishes. A green variant of the Asian Arowana breeds at the headwaters of Sungai Endau, which is one of the few natural habitats left for this Endangered species in Peninsular Malaysia. Predatory fishes sought after by sports fishermen, including the Malayan Mahseer (Kelah), Flower Snakehead (Toman Bunga), and Hampala Barb (Sebarau) lurk in the deep pools (lubuk) along the rivers. While permits are given for angling at certain spots, the key spawning sites are strictly off-limits.