Laboratory for Terrestrial Remote Sensing

IDENTIFICATION OF HUON TREE KANGAROO (Dendrolagus matschiei) HABITAT IN PAPUA NEW GUINEA (PNG) THROUGH INTEGRATION OF REMOTE SENSING AND in situ DATA

• Introduction

  The island of New Guinea, located directly north of the Australian continent, is the world’s largest and highest tropical island and is considered one of four remaining “major tropical wilderness areas” (along with Northwest Amazonia, the Guyana Shield, and the Congo basin). Papua New Guinea (PNG), which occupies the eastern half of the island, and its western neighbor Irian Jaya are both members of an elite group of nations which combined may account for 60-80% of the world’s biodiversity (Mittermeier and Werner, 1998). PNG is considered to have high potential for conservation efforts due to the high percentage of remaining forest, high species richness and endemism, and relative lack of comprehensive protected areas (Dinerstein and Wikramanayake,1993; Osborne, 1995).

  Many previous ecological studies in PNG have focused on the development of species inventories which document the biodiversity of a region (Flannery, 1995; Takeuchi, 1999). However, since maintenance of the biological integrity of terrestrial ecosystems over the long term will require conservation of large, contiguous tracts of forests, some researchers have proposed a move away from the production of species inventories to studies which undertake the identification of species which play key roles in existing ecosystems (Dinerstein and Wikramanayake,1993). The emphasis of these studies would shift from attempting to identify, catalougue and map all species, to actively assisting in conservation projects which attempt to maintain community and ecosystem function (Osborne, 1995).

  One example of such an effort is the ongoing Tree Kangaroo Conservation Program (TKCP). This program began in 1996 as a focused species study of threatened tree kangaroos on the Huon Peninsula in PNG. Tree kangaroos are the largest mammals in the PNG rainforest and under pressure from increasing habitat destruction and over hunting. Since then the program has expanded into a comprehensive community-based effort to preserve rainforest habitat. 2001 marks the program’s sixth year working in PNG. In the first five years the program successfully documented tree kangaroo natural history and made initial estimates of wild tree kangaroo populations. Just as importantly, the program has established relationships with landowners, national and local government representatives, and other conservationists in PNG. These relationships have put the program in a position to pursue and achieve more ambitious goals in the years ahead. Chief among these goals is the establishment of a large Wildlife Management Area (WMA) in tree kangaroo habitat.

  The project described in these pages seeks to bring the capabilities of Remote Sensing technology to the efforts of the TKCP by providing the first comprehensive data on the distribution of suitable habitat for the Huon Tree Kangaroo (Dendrolagus matschiei). This effort will involve the classification of Landsat-7 enhanced thematic mapper (ETM+) satellite imagery to create an accurate and up to date landcover map of the area of interest, and to use this map in conjunction with existing field data documenting population density of the Huon Tree Kangaroo (Dendrolagus Matschiei) in an attempt to identify preferred habitat for the species.

• Study Area

  PNG is a country of very rugged terrain and high rainfall; where as much as two thirds of the land is covered with undisturbed moist tropical forest. There are over 34 million hectares of this forest in the country, and it remains one of the few tropical locations worldwide where habitat loss and deforestation have occurred at relatively low levels (Beehler, 1993). PNG is home to over 15,000 species of plants-including 2000 orchids and over 2000 types of ferns-and contains ecosystems ranging from coastal savanna, through lowland and montane rainforest, to subalpine forest and alpine grassland (Johns, 1993).

  Two distinct wind and rainfall patterns determine the climate in PNG. From April to October, southeasterly trade winds prevail and from Novermber to March, warm northwesterly monsoonal winds blow and most frequent rainfalls occur during this season. Rainfall in some areas exceeds 1000 cm per year and most of the country receives annual rainfall of between 250 and 350 cm (Osborne, 1995). PNG lies at the collision of the Australian and Pacific tectonic plates and is a geologically young and active region which contributes to its considerable landscape, ecosystem and species diversity (Agardy and Pernetta, 1993).

  Within the diverse landscape of PNG a unique region is the Huon Peninsula, located on the northeast coast of the country. Formed when large volcanic islands of the Bismarck plate collided with the northern edge of the Australian plate the Huon is geologically young and is estimated to have docked with the New Guinea mainland only 3.0-3.7 million years ago (Hovius et al., 1998). The mountains of the Huon peninsula, which include the Finisterre, Sarawaged, Cromwell, and Rawlinson Ranges, are the highest and most rugged Papua New Guinea’s outlying ranges, with several peaks exceeding 4000 meters elevation. These ranges are composed of geologically young, rapidly rising limestone capped ridges with important wet highland forest (Saulei and Beehler, 1993). The Finisterre range is rising at an estimated rate of 0.8-2.1 mm/yr, making it one of the fastest growing mountain ranges on earth (Abbot et al., 1997).

  The Huon’s montane and subalpine zones are securely isolated from the Central Ranges by the Markham and Ramu River Valleys. A high elevation connection between the Huon and the Central Ranges has never existed and as a result these mountains support more PNG mainland endemic vertebrate species than any other known region, including 3 honeyeaters and 2 Birds of Paradise (Beehler, 1993). Because the mountains are so young there has been less time for specialized high altitude mammals to evolve as they have on the Central Ranges in PNG. As a result some mid-montane species have expanded their range to higher altitudes (Flannery, 1995). Among these species is the endemic Huon tree kangaroo (Dendrolagus matschiei). The Huon is also home to an estimated 5000 species of plants making it one of the richest areas in New Guinea (Johns, 1993). The Sarawaged Range, east of the Finisterre, includes at least five species of endemic frogs (Allison, 1993) and is also important to the study and conservation of nonmarine invertebrates (Miller et al., 1993). The northern Huon coast contains large areas of raised coral reef terraces which are also subject to rapid uplift, and are considered a priority area for conservation (Agardy and Pernetta, 1993).

  Although richly endowed with natural resources, development in PNG has been hampered by the rugged terrain and the high cost of developing infrastructure. Although resource developement projects (forestry, mining, plantation agriculture, oil extraction) have led to destruction of some habitat, the major threat to biodiversity in PNG is from the growth and migration of the human populations leading to increased forest clearing for subsistence agriculture (Osborne, 1995).

  The Program’s work is centered on the Central and Western Huon Peninsula of PNG, in the YUS Local Government Area (LGA) of Kabwum District. This region is located between 5° 45′ and 6° 20′ south latitude, and 146° 30′ and 147° west longitude on the north side of the Peninsula. YUS encompasses the watersheds of the Yupna, Urawa, and Som rivers and associated administrative and cultural areas and includes a portion of the Finisterre mountains, the youngest mountain range in PNG, and also a large portion of the Sarawaged mountains. The YUS LGA contains a broad elevational range from coastal to alpine zones and contains vegetation types which encompass the habitat of all the known Huon endemic species including Dendrolagus matschiei.

• D. matschiei

  DENDROLAGUS MATSCHIEI

  Tree kangaroos are classified in the family Macropodidae, genus Dendrolagus. Nine species of tree kangaroos have been identified to date, two in far north Queensland, Australia and the remaining seven on the island of New Guinea. All are forest dwellers and the four species found in PNG occupy habitat in rugged mountainous terrain.

  Tree kangaroos in the wild are primarily herbivorous and eat a variety of leaves, bark, flowers, and fruits. In those species studied, feeding tended to take place in the mid and upper canopy of the forest. Since they are the heaviest of the arboreal marsupials, tree kangaroos are dependent on mature forest where trees are large enough to support their weight (Hutchins and Smith, 1990).

  Although several species of tree kangaroo are well studied, little is known about the ecology and behavior of Dendrolagus matschiei (Newell, 1999). The species is restricted to the mountains of the Huon peninsula and nearby Umboi and New Britain. The populations on Umboi and New Britain are believed to have been introduced by humans. The species occupies an elevational range between 1000 and 3300 meters and are believed to be largely solitary (Hutchins and Smith, 1990). Very limited radio tracking data suggests a home range of 0.25 square kilometers for a single individual (Flannery, 1995). In captivity the species exhibits a diurnal behavior pattern but it is not known if this is also true for wild animals.

  Tree kangaroos have been hunted extensively on the Huon for many generations and as a result are very secretive and rarely seen. D. matschiei is considered to be threatened due to loss of habitat caused by increasing subsistence agriculture, a result of the steadily increasing human population in the region (IUCN, 2001).
  

• Remote Sensing in Situ Data

  Remote sensing can be loosely defined as the process of obtaining information about an object without touching it. More specifically, remote sensing refers to the process in which a sensor mounted on some type of platform collects data about a region of interest from a distance. Historically, platforms and sensors have ranged from simple cameras attached to pigeons to more sophisticated camera/aircraft systems. More recently they have come to include high altitude satellites equipped with complex digital sensors which are capable of collecting information over a wide range of the electromagnetic spectrum. The advanced capabilities of these recent systems have led to the expanding use of remotely sensed imagery for ecological research.

  Three important characteristics contribute to the utility of satellite remote sensing imagery; the availability of data in a variety of scales (multi-scale), the availability of data at regular time intervals (multi-temporal), and the ability to measure a broad range of the electromagnetic spectrum (multi-spectral). In addition, satellite remote sensing imagery has also become increasingly available and affordable in recent years, allowing the application of digital image processing techniques to a wide variety of research uses. Much of this research involves the attempt to evaluate and quantify the relationship between landcover and ecological processes and to examine how the earth is changing and what the consequences of these changes are for living things.

  The project described in these pages seeks to bring the capabilities of Remote Sensing technology to the efforts of the TKCP. Classification of Landsat-7 Enhanced Thematic Mapper (ETM+) imagery will provide the first comprehensive data on the distribution of suitable habitat for the Huon Tree Kangaroo (Dendrolagus matschiei). This information will be used to determine priority areas for conservation of the species and it’s associated habitat in the YUS region.

  For more detailed remote sensing information visit Nasa’s Remote Sensing Tutorial.

• Summary

  In 1993, the PNG Department of Environment and Conservation conducted a national Conservation Needs Assessment (CNA) which identified areas of concern within seven general categories: Native Flora; Warm-blooded Vertebrates; Fishes, Amphibians, and Reptiles; Nonmarine Invertebrates; Freshwater Wetlands; Coastal and Marine Ecosystems; and Humid Forest Environments. The CNA indicated that PNG possesses rich and unique biodiversity and that immediate conservation action is necessary to protect these habitats from threats resulting from a variety of development activities.

  The CNA also stressed the need for ongoing professional training for PNG conservation biologists and land managers, and the importance of including local populations and landowners in the conservation process. Unlike many tropical nations, the Government of PNG recognizes traditional ownership of land and approximately 97% of land remains in local hands. Local populations have sole authority to designate protected areas and manage them once established, and their cooperation is integral to conservation efforts within PNG.The landscape of the Huon peninsula will most likely undergo rapid change in the near future due to increasing population and increased clearing of forest for subsistence agriculture.

  Although considerable vegetation data is available for PNG, this data is dated and of insufficient scale to be useful for management purposes in the study area. Successful classification of Landsat ETM+ satellite data will provide the most up to date vegetation data available at a scale suitable for research and conservation efforts within the YUS LGA. Once accuracy assessment is complete, the data will be made available to other researchers and local government authorities to assist with their conservation and management efforts in the region.

  Although several species of tree kangaroo in PNG are well studied, little is known about the ecology and behavior of D. matschiei (Newell, 1999). The habitat model developed by the project will provide the first comprehensive data on the distribution and habitat preferences of the Huon Tree Kangaroo (Dendrolagus Matschiei). This information will be used to determine priority areas for conservation of the species and it’s associated habitat in the YUS region. Ultimate success will be indicated by use of data and maps produced by the project to assist in the designation of a Wildlife Management Area which will protect habitat for the species and ensure it’s continued existence and importance for the people of PNG.

• References

  Abbott, LD; Silver, EA; Anderson, RS; Smith, R; Ingle, JC; Kling, SA; Haig, D; Small, E; Galewsky, J; and Sliter, W. 1997. Measurement of tectonic surface uplift rate in a young collisional mountain belt. Nature. 385: 501-507.

  Agardy, MT and Pernetta, J. 1993. A Preliminary Assessment of Biodiversity and Conservation for Coastal and Marine Ecosystems in Papua New Guinea. in Beehler, BM (ed.) Papua New Guinea Conservation Needs Assessment: Volume 2. Corporate Press Inc., Landover. 381-421.

  Allison, A. 1993. Biodiversity and Conservation of the Fishes, Amphibians, and Reptiles of Papua New Guinea. in Beehler, BM (ed.) Papua New Guinea Conservation Needs Assessment: Volume 2. Corporate Press Inc., Landover. 156-225.

  Beehler, BM. 1993. Introduction to the CNA Report, Volume 2. in Beehler, BM (ed.) Papua New Guinea Conservation Needs Assessment: Volume 2. Corporate Press Inc., Landover. 1-14.

  Dinerstein, E and Wikramanayake, ED. 1993. Beyond “hotspots”: How to prioritize investments to conserve biodiversity in the Indo-Pacific region. Conservation Biology. 7: 53-66.

  Flannery, TF. 1995. Mammals of New Guinea. Cornell University Press, Ithaca, New York.

  Hovius, N; Stark, CP; Tutton, MA. 1998. Landslide-driven drainage network evolution in a pre-steady-state mountain belt: Finisterre Mountains, Papua New Guinea. Geology. 26 (12): 1071-1074.

  Hutchins, M and Smith, R. 1990. Biology and Status of Wild Tree Kangaroos. in Roberts, M and Hutchins, M (eds.) The Biology and Management of Tree Kangaroos. AZA Marsupial and Monotreme Advisory Group: Bulletin no. 1. 1-7.

  International Union for the Conservation of Nature. 2000. 2000 IUCN Redlist of Threatened Species. http://www.redlist.org/.

  Johns, RJ. 1993. Biodiversity and Conservation of the Native Flora of Papua New Guinea. in Beehler, BM (ed.) Papua New Guinea Conservation Needs Assessment: Volume 2. Corporate Press Inc., Landover. 15-75.

  Miller, SE; Cowie, R; Polhemus, D; and Eldredge, L. 1993. Biodiversity and Conservation of the Nonmarine Invertebrate Fauna of Papua New Guinea. in Beehler, BM (ed.) Papua New Guinea Conservation Needs Assessment: Volume 2. Corporate Press Inc., Landover. 226-325.

  Mittermeier, RA and Werner, TB. 1998. Wealth of Plants and Animals unites “megadiversity” countries. Tropicus 4 (5): 4-5.

  Newell, GR. 1999. Australia’s Tree-Kangaroos: Current Issues in their Conservation. Biological Conservation. 87: 1-12.

  Osbourne, PL. 1995. Biological and cultural diversity in Papua New Guinea: Conservation, conflicts, constraints and compromise. Ambio. 24: 231-237.

  Saulei, SM and Beehler, BM. 1993. Biodiversity and Conservation of Humid Forest Environments in Papua New Guinea. in Beehler, BM (ed.) Papua New Guinea Conservation Needs Assessment: Volume 2. Corporate Press Inc., Landover. 422-434.

  Takeuchi, W. 1999. New Plants from Crater Mt., Papua New Guinea, and an Annotated Checklist of the Species. SIDA: Contributions to Botany. 18 (4): 941-986.

• Links

  University of Rhode Island
  https://www.uri.edu/
  URI Laboratory for Terrestrial Remote Sensing
  https://web.uri.edu/ltrs/

  Nasa’s Remote Sensing Tutorial
  http://rst.gsfc.nasa.gov/starthere.html
  Landsat-7 Homepage
  http://www.landsat.gsfc.nasa.gov/index.htm

  Tree Kangaroo Conservation Program (TKCP)
  http://www.rogerwilliamsparkzoo.org/conservation/TKCP_main.htm