ECOLOGY IN CHAPTER 1

CHAPTER 1 also has the largest tract of tropical lowland Ecology in Palau forest in the Pacific (Kitalong, 2014). In 1979, nearly 218 km2 or 52% of Palau’s land was The landscape of Palau is one of a medium to covered with lowland forests. Yet, slowly, forests low volcanic island chain with large fringing ECOLOGY IN PALAU are being cut for homesteads, development and/or barrier reefs. The Palauan island chain and roads. Forest trees and plants are valued as has all three-island types: volcanic, limestone Christopher Kitalong, David Mason sources of timber, food, medicine, habitat for and atolls. Palau’s proximity to the Asian other species, and for their cultural and aesthetic continent, Philippines, and Indonesia results Settings value (Kitalong, 2008). in increased radiation of plant taxa compared The archipelago of Palau was formed during to other islands in Micronesia. Despite being the Eocene epoch, 40 million years ago by the closest Micronesian island to larger land the of the Pacific Plate beneath masses, Palau is still relatively isolated. Due the Philippine Plate along the Kyushu-Palau to these factors, Palau has the greatest number Ridge (PALARIS, 2009). Palau lies on the of endemics and highest species richness in east edge of the Line, which divides the Micronesian island chain (Canfield, 1981). the deeper of the Central Pacific Basin However, the amount of arable soil is very from the partially submerged continental areas limited and very prone to erosion. As suggested of andesite. Volcanism ceased 20 million years by the USDA report deposited at Forestry ago and was succeeded by submergence of Service in Palau, islands and formation of the barrier reef began. During this same period of submergence, uplift “The most fertile soils in this survey occurred and the limestone islands and raised area are those that are under forest atolls of southern Palau were formed. The vegetation, mainly because of large limestone formed beneath the sea and became amounts of organic matter, which exposed through uplift that occurred in the last provides nutrients for plants. As fallen 3-4 million years. Subaerial erosion formed leaves and branches rot, organic matter the karst landforms seen today in the limestone and nutrients are returned to the soil. islands (Kayanne et al., 2002). Babeldaob, Before these nutrients can be reached Fig. 1. Map of Palau, directly south of Japan and east of the Philippines. the largest volcanic island, covers an area of through the soil and lost, roots absorb 2 2 365 km (including 33 km of mangroves) and them and the process begins again. The Republic of Palau is the westernmost Irian Jaya, West Papua and 870 km east of the extends 37 km in length and 6 to 13 km in In this way, forest soils retain their archipelago of the Caroline Islands in Micronesia Philippines (PALARIS, 2012, Fig.1). Palau has width. The highest elevation for this old volcanic fertility. In addition, the forest canopy with approximately 586 islands covering a land a diverse assemblage of over 1,389 plants of island is 213 m at Mount Ngerchelchuus in and layer of fallen and dead leaves 2 area of 535 km . The archipelago extends 700 which 802 are native and 571 are introduced; at central Babeldaob with the volcanic islands of (called litter) provide protection from km northeast to southwest, from latitudes 8°12' least 135 of the native plants are endemic and Ngarkebesang, Malakal and Koror to the south, erosion (United States Department of to 2°48' North/South and longitudes 131°07' has the highest species endemism per area in and the atolls of Kayangel state to the north Agriculture, 2009).” to 134°44' East/West, lying 900 km north of Micronesia(Costion and Lorence, 2012). Palau (Kitalong, 2014).

12 13 CHAPTER 1 ECOLOGY IN PALAU ECOLOGY IN PALAU CHAPTER 1

Heavy, unmitigated development and agriculture Vegetation types Dalbergia candenatensis (Dennst.) Prain and microcephalus Wagner & Lorence, P. otobedii causes sedimentation and loss of this thin, fertile Nypa fruticans Wurmb. Mangroves are very Wagner & Lorence, Alphitonia carolinensis layer soil. In general, the most favorable pH There are three main vegetation types on dense forest types and when left undisturbed, Hosok., Calophyllum inophyllum (L.) var. range for plant development is between 5.5 to the limestone rock islands of Palau: strand can expand quite rapidly in Palau (Canfield, wakamatsui (Kaneh.) Fosberg & Sachet, C. 6.5 in mineral soil and 5.0 to 6.0 in organic soil, vegetation, which found on atolls and coastal 1981; Costion and Lorence, 2012; Donnegan et soulattri Burm.f., C. pelewense P.F. Stevens, and the acidity of the mostly mineral soil on areas of the main volcanic island and rock al., 2007; Kitalong, 2014). Symplocos racemosa Roxb. var. palauensis most of Palau (4.9-5.1) limits intense export- islands; limestone forests that are restricted to (Koidz.) Noot., Manilkara udoido Kaneh., and based agriculture (Foy, 1992). The majority the larger limestone “Rock Islands” and consist 2. Swamp forest Fagraea ksid (Gilg & Bened). The forest is of soil in Palau is highly ferrous saprolite that of a mixture of limestone-specific species and This forest type tends to buffer mangrove areas dense, multilayered, and structurally complex is very prone to landslides and therefore does species shared with the large volcanic islands in slightly brackish water or exists around here and some species thrive in buffer zones not retain arable topsoil well (Hurst, 1977; of Palau; and mangrove forests that occupy the fresh water sources, mostly wetlands buffering between volcanic forests and grassland, like United States Department of Agriculture, 2009). brackish water zones, where salt and freshwater riparian/ravine areas. Horsfieldia irya (Gaertn.) Planchonella obovata (R.Br.) Pierre, Rhus Increased development activity and agriculture mix. The larger volcanic islands of Babeldaob Warb., H. palauensis Kaneh., Cynometra taitensis (Guillemin), Cerbera floribunda K. without soil erosion mitigation has resulted in and Koror are the most species rich with ramiflora L., Barringtonia racemosa (L.) Schum. and Cerbera manghas L. (Canfield, increased acidification of the soil and loss of vegetative types include limestone forest, strand Spreng.,Campnosperma brevipetiolata Volk., 1981; Costion and Lorence, 2012; Donnegan et arable topsoil. This activity will be addressed vegetation mangrove forest, as well as lowland and Heritiera littoralis Aiton, are often found in al., 2007; Kitalong et al., 2013 ). later in this chapter in section 1.5, which forests, swamp/wetland forests, riparian forests, the intact freshwater swamps. Hibiscus tiliaceus discusses land use by foreign occupancy in interior forests and savannas (Canfield, 1981; L. is opportunistic and grows very well, and in 4. Savannas/Grassland Palau. The areas in Palau that are used for plant Costion and Lorence, 2012; Donnegan et al., dense clusters, in these areas(Canfield, 1981; Although most of these are a result of past cultivation are lowland and/or terraced upper 2007; Kitalong et al , 2013). A more detailed Costion and Lorence, 2012; Donnegan et al., agriculture the predominant trees are Pandanus forested areas, where heavy mulching, fertilizer listing of vegetative types is found below. 2007; Kitalong, 2014). tectorius Parkinson ex Du Roi, Commersonia or other soil treatment is necessary. Furthermore, bartramia (L.) Merr., and Melastoma the low-nutrient, hard and porous substrate of 1. Mangrove 3. Interior volcanic forest malabathricum L. Some other important trees in the limestone islands and sand substrate of the Mangroves are important buffer zones that Occurring primarily on volcanic substrates, these areas in include Morinda citrifolia L., M. atolls are not suitable for large-scale agriculture. reduce sedimentation along coastal areas. They interior volcanic forest encompasses distinct pedunculata Valeton., and Wikstroemia elliptica These factors make plant growth difficult, also provide a nursery and habitat for marine, subtypes of forest in undisturbed ecosystems. Merr. on the borders of the forested areas which from an evolutionary perspective may intertidal and terrestrial fauna. The mangroves Moving inland from the mangroves and swamps, (Canfield, 1981; Costion and Lorence, 2012; affect immigration rates and cause specific of Palau are species-rich extending along tidal the species include Casuarina equisetifolia Donnegan et al., 2007; Kitalong et al. , 2013). adaptive changes in original taxa to survive zones with reduced wave activity. The regularly L. in sparse, rocky and/or disturbed areas. harsh circumstances leading to differentiation occurring species found here include Rhizophora Farther inland, the forest grades into a mixed- 5. Limestone forest type of species. Natural and human impact factors, mucronata Lam., Rhizophora apiculata Blume, forest canopy that includes Campnosperma On the limestone substrate throughout Palau, discussed in the upcoming sections, leave Palau Bruguiera gymnorrhiza (L.) Lam., Ceriops tagal brevipetiolata Volk., Horsfieldia irya (Gaertn.) organic matter from the vegetation and fauna with vegetation types similar to other areas of the (Perr.) C. B. Rob., Dolichandrone spathacea (L.) Warb., H. palauensis, Myristica hypargyraea droppings forms a thin layer in places over the Pacific and Southeast Asia. Vegetative types are Seem, Sonneratia alba J.E. Smith, Avicennia A. Gray subsp. insularis (Kaneh.) W.J. de coral rock. The limestone substrate is naturally mainly dependent on substrate/soil (Donnegan et marina (Forssk.) Vierh., Lumnitzera littorea Wilde, Atuna racemosa Raff. subsp. racemosa, steep, porous, and extremely rugged, unless al., 2007). (Jack) Voigt, Xylocarpus granatum Koenig, Maranthes corymbosa Blume, Serianthes altered by constant natural or human based Scyphiphora hydrophylacea C.F. Gaertn., kanehirae Fosberg var. kanehirae, Phyllanthus activities. Limestone uplifts border the ocean

14 15 CHAPTER 1 ECOLOGY IN PALAU ECOLOGY IN PALAU CHAPTER 1 and are typically undercut by waves and bio- Valeton and, Bikkia palauensis Valenton. medicines and flavoring that include many Glossary erosion are typically quite difficult to access. Furthermore, Casuarina equisetifolia L. is an native and endemic plants for which local Dominant species are Eugenia reinwardtiana opportunistic, large tree that thrives in these people found uses. Examples of these plants are Atolls: A roughly circular coral reef surmounted (Blume) A. Cunn ex DC., Rinorea bengalensis areas. Phaleria nisidai Kaneh., Premna serratifolia L., by a chain of closely spaced., low coral islets (Wall.) Kuntze, Ficus microcarpa L.f. Syzygium samarangense Blume. as well as other that encircle or nearly encircle a shallow lagoon Hornem, Canarium sp., Intsia bijuga (Colebr.) 7. Ravine and riparian forest species used by habitants for medicine and food in which there is no land or islands of non-coral Kuntze, Planchonella obovata (R.Br.) Pierre, Palau’s ravines and riparian areas have the and planted within the homestead. Furthermore, origin; the reef is surrounded by open sea Psychotria cheathamiana Fosb., Guettarda densest populations of primary and secondary in Palau these homestead plants would include speciosa L., Syzygium mesekerrak Lorence & forest. The plant species in these ravines and various taros such as Cyrtosperma merkusii Karst: (topography):. The relief an area Byng, Syzygium palauensis (Kaneh.) Hosok., riparian areas disperse into disturbed areas (Hassk.) Schott., Colocasia esculenta (L.) underlain by limestone that dissolves in differing Calophyllum soulattri Burm.f., and Horsfieldia and savannas, and are the main compositional Schott. and Alocasia macrorrhizos (L.) G. Don, degrees, thus forming numerous depressions or palauensis Kaneh. Other notable species include vegetative element of secondary forests in Palau. as well as plants found in the taro patches within small basins Casearia hirtella Hosok., Garcinia matsudai Inocarpus fagifer (Parkinson) Fosberg, Quassia the villages (Olsudong, 2002; Wickler, 2002). Kaneh., G. rumiyo Kaneh., Cycas micronesica indica (Gaertn.) Noot., Colona scabra (Sm.) Sand: As a soil separate., individual rock or Hill, Pandanus dubius Spreng., Phyllanthus Burret, Cynometra ramiflora L., Dolichandrone 9. Farm/sers vegetation mineral fragments from 0.05 millimeter to 2.0 macrosepalum (Hosokawa) W.L.Wagner and spathacea (L.) Schum., and Semecarpus This human-influenced vegetation includes millimeters in diameter. Most sand grains consist Lorence, Flacourtia rukam Zoll. & Moritzi venenosus Volkens. are common plant species in plants that are left loosely cultivated and of quartz. As a soil textural class. A soil that is var. micronesica Fosberg & Sachet., Aidia these areas. harvested as needed. These areas may be 85 percent or more sand and not more than 10 racemosa (Cav.) Tiring., Meryta senff tiana Other than the typical types of vegetation interlaced within normal vegetation areas in the percent clay Volkens, Polyscias macgillivrayi (Benth,) mentioned above, in order to understand understory, or cultivated heavily and harvested Harms, Cleidion sessile (Kaneh. & Hatus.), real changes in landscape it is important to for economic purposes. Some plants, such as Saprolite: Soft, friable, weathered bedrock Premna serratifolia L., Cyrtandra todaiensis include two other vegetative types. The first is Nypa fruticans Wurmb. And other mangrove that retains the fabric and structure of the Kaneh., Badusa palauensis Valeton, Psychotria homestead/mesei vegetation, important not only plants were harvested as needed for traditional parent rock and exhibits extensive intercrystal hombroniana variants and Wikstroemia elliptica to traditional Palauan villages, but to the current construction. These managed natural landscapes, and intercrystal weathering. In pedology, the Merr. The largest trees include Trema orientalis Palauan homes as well. The second is farm/sers within the mangrove forests, were maintained term “saprolite'' has been used to refer to any L. Blume and Artocarpus mariannensis Trecul. vegetation, which would include cultivated lands through harvest of naturally occurring species unconsolidated residual material that underline (Canfield, 1981; Costion and Lorence, 2012; further away from homes as well as those lands from their natural habitat (Kitalong and Tadao, the soil and grades had to bedrock bellow Donnegan et al., 2007; Kitalong et al , 2013).. cultivated by non-Palauan colonizers. These two 2010). On the other hand, plantations of vegetation types are important to the livelihood Manihot esculenta Crantz. and Ananas comosus Swamp: An area of low , saturated ground., 6. Strand of the people. Farming practices either alter the (L.) Merr. were introduced and harvested for intermittently or permanently covered with water Strand communities are found on the atolls of landscape or are managed natural landscape, economic purposes. These commercial farms and vegetated dominantly by shrubs and trees, Palau, the low coral limestone rock islands, which utilizes natural vegetation areas for commanded the alteration of vegetation in large with or without the accumulation of peat and on both coasts of the big volcanic island, sustainable harvest. areas throughout Palau (Iida et al., 2010; Iida et Babeldaob, inside the fringing reef, depending al., 2011). Terrace (geologic): An old alluvial plain., on substrate. Strand species common to Palau 8. Homestead/mesei vegetation ordinally flat or undulating, bordering a river, a include Cordia subcordata Lam., Scaevola This human-influenced vegetation consists of lake, or the sea taccada (Gaertn.) Roxb., Badusa palauensis economically important plants used daily for

16 17 CHAPTER 1 ECOLOGY IN PALAU ECOLOGY IN PALAU CHAPTER 1

Scientific Common Palauan Topsoil: The upper part of the soil., which is Colona scabra (Sm.) Burret, chuchab the most favorable material for plant growth. It is ordinally rich in organic matter and is used to Cleidion sessile Kaneh. & Hatus. top dress road banks, lawns and land affected Colocasia esculenta (L.) Schott. taro dait, kukau mines Cordia subcordata Lam. baderirt Index of Genera and Species Cycas micronesica Hill cycad ocheall Cyrtandra todaiensis Kaneh. melkii Scientific Common Palauan Cyrtosperma merkusii (Hassk.) Schott. giant taro brak Aidia racemosa (Cav.) Tirveng. kerumes Cynometra ramiflora L. ketenguit Alocasia macrorrhizos (L.) G.Don bisechrabelau Dalbergia candenatensis (Dennst.) Prain Alphitonia carolinensis Hosok. chelebiob Dolichandrone spathacea (L.) Seem. riu Ananas comosus (L.) Merr. pineapple ongorngebard Eugenia reinwardtiana (Blume) A. Cunn kesiil Artocarpus mariannensis Trecul wild breadfruit chebiei, meduuliou ex DC.

Atuna racemosa Raff. subsp. racemosa parinarium nut cheritem Fagraea ksid Gilg & Bened. ksid

Avicennia marina (Forssk.) Vierh. dadaiit Ficus microcarpa L.f. var. microcarpa lulk

Badusa palauensis Valeton ralm Flacourtia rukam Zoll. & Moritzi var. chemechong micronesica Fosberg & Sachet Barringtonia racemosa (L.) Spreng. koranges Garcinia matudai Kaneh. tilol Bikkia palauensis Valeton rur Garcinia rumiyo Kaneh. tilol Bruguiera gymnorrhiza (L.) Lam. black mangrove kodenges, denges Guettarda speciosa L. blau Calophyllum inophyllum L. var. btaches wakamatsui (Kaneh.) Fosberg & Sachet linneaus Horsfieldia palauensis Kaneh. chersachel

Calophyllum soulattri Burm. f. olebtaches Heritiera littoralis Aiton saltwater chestnut chebichech

Calophyllum pelewense P.F. Stevens chesemolech Hibiscus tiliaceus L. corkwood chermall, eremall Commersonia bartramia (L.) Merr. bebechelut Horsfieldia irya (Gaertn.) Warb. chemeklachel

Campnosperma brevipetiolata Volk. kiu, kelelacharm Horsfieldia palauensis Kaneh. chersachel

Canarium sp. mesecheues Inocarpus fagifer (Parkinson) Fosberg keam

Casearia hirtella Hosok. kesengelngolm Intsia bijuga (Colebr.) Kuntze dort

Casuarina equisetifolia L beefwood, ironwood ngas Lumnitzera littorea (Jack) Voigt mekekad (ngemoel)

Cerbera floribunda K. Schum. chemeridech Manihot esculenta Crantz tapioca, cassava diokang Cerbera manghas L. chemeridech Maranthes corymbosa Blume bkau

Ceriops tagal (Perr.) C. B. Rob. biut Manilkara udoido Kaneh. udeuid

18 19 CHAPTER 1 ECOLOGY IN PALAU ECOLOGY IN PALAU CHAPTER 1

Scientific Common Palauan Scientific Common Palauan matakui Melastoma malabathricum L. Syzygium samarangense Blume Merr. & rebotel L.M. Perry rembu Morinda citrifolia L. noni, Indian mulberry ngel Symplocos racemosa Roxb. var. chebtui Morinda pedunculata Valeton kesengelngel palauensis (Koidz.) Noot.

Meryta senfftiana Volkens omechidel Syzygium palauense (Kaneh.) Hosok. orenged

Myristica hypargyraea A. Gray subsp. Trema orientalis (L.) Blume charcoal tree chelodechoel insularis (Kaneh.) W.J. de Wilde Wikstroemia elliptica Merr. tebudel Nypa fruticans Wurmb. nypa palm teuechel Xylocarpus granatum Koenig meduulokebong Quassia indica (Gaertn.) Noot. cheskeam

Pandanus tectorius Parkinson ex Du Roi screw pine, pandanus ongorraked, ongor, Such

Pandanus kanehirae (Hosokawa) W.L. buuk

Phyllanthus macrosepalus (Hosokawa) ngolm References W.L.Wagner & Lorence udoud, dudurs Canfield, J. E. 1981. Palau: Diversity and Status of the Native Vegetation of a Unique Pacific Island Phyllanthus palauensis Hosok. Ecosystem. Newsletter of the Hawaiian Botanical Society 20: 14-21. Phyllanthus otobedii W.L. Wagner & Lorence Costion, C. M. and D.H. Lorence 2012. The Endemic Plants of Micronesia: A Geographical Checklist and Commentary. Micronesica 43 : 51-100. Polyscias macgillivrayi (Benth.) Harms bngei Donnegan, J. A., S.L.Butler, O. Kuegler, B. J. Stroud, B. A. Hiserote, and K.Rengulbai 2007. Palau's Premna serratifolia L. chosm Forest Resources, 2003. US Department of Agriculture, Forest Service, Pacific Northwest Research Psychotria cheathamiana Fosberg Station.

Psychotria hombroniana variants Foy, C. D. 1992. Soil Chemical Factors Limiting Plant Root Growth, Limitations to Plant Root Growth. Springer (New York) pp. 97-149. Planchonella obovata (R.Br.) Pierre chelangel

Phaleria nisidai Kaneh ongael, delal a kar Hurst, V. J. 1977. Visual Estimation of Iron in Saprolite. Geological Society of America Bulletin 88: 174-176. Rhizophora apiculata Blume bngaol

Rinorea bengalensis(Wall.) Kuntze, Iida, A., M. Noguchi, S. Osawa and M. Ishikawa 2010. A Study on the Sustainable Land Use of Villages Based on Watershed Management; Babeldaob Island, Republic of Palau. Iida, A., S. Osawa, Rhus taitensis Guil. cheues and M. Ishikawa, 2011. A Study on the Past and Present Conditions of the Development Sites of the korrai, kirrai, raelchol Japanese Colony in Micronesia : A Case Study at the Plantations and the Bauxite Mining Lands on the Scaevola taccada (Gaertn.) Roxb., Babeldaob Island, the Republic of Palau Papers on City Planning 46: 319-324. Scyphiphora hydrophyllacea C.F. Gaertn. kuat Kayanne, H., H. Yamano, and R. H. Randall 2002. Holocene Sea-Level Changes and Barrier Reef Semecarpus venenosus Volkens tonget Formation on an Oceanic Island, Palau Islands, Western Pacific. Sedimentary 150: 47-60.

Serianthes kanehirae Fosberg var. kumer, ukall Kitalong, A. H. 2008. Forests of Palau: A Long Term Perspective. Micronesica 40: 8-30. kanehirae

Sonneratia alba Sm. mangrove apple urur Kitalong, C. and V. R. Tadao 2010. The Use of Plants for Fishing and Building: personal communication. Syzygium mesekerrak Lorence & Byng mesekerrak

20 21 CHAPTER 1 ECOLOGY IN PALAU

Kitalong, A. H., R. A. DeMeo and T. Holm. 2013. Native Trees of Palau: A Field Guide, 2nd ed. The Environment, Inc, Koror, Palau. 239 p. The Environment, Inc. CHAPTER 2

Kitalong, A. H. 2014. Native trees of Palau: A Field Guide, 2nd ed. The Environment, Inc, Koror, Palau.

Olsudong, R. 2002. Oral Traditions and Archaeology in Micronesia: An Attempt to Study Past HISTORY OF LAND USE Ideology in a Built Environment, The Melaka Papers: Proceedings of the 16th Congress of the Indo- Christopher Kitalong, David Mason Pacific Prehistory Association, Melaka, Malaysia 1 to 7 July 1998, pp.153-160.

PALARIS 2009. Executive Summary: Submission to the Commission on the Limits of the Continental Initial Immigrants Shelf, Pursuant to Article 76 of the UN Convention on the Law of the Seas, In: (Development, P. A. L. a. R. I. S. P. M. o. R. a. ed.) Republic of Palau (Koror, Palau) Coastal settlements in Babeldaob date back more rock islands were the deciding factors in the than 4000 years (Clark et al., 2006; Fitzpatrick, Rock Islands Southern Lagoon’s nomination PALARIS 2012. Republic of Palau Sustainable Land Management Policy. In: Sustainable Land 2003), however due to acidity, sedimentation as a UNESCO World Heritage site in 2012 Management Policies UNDP. Palau Automated Land and Resource Information System (PALARIS) (Ministry of Public Infrastructure, I. a. C. ed.): Ministry of Resources and Development, Republic of and intertidal changes, archaeological remains (Reepmeyer et al., 2011, Fig. 2). Archeological Palau (Koror, Palau) pp. 1-49. on the large island of Babeldaob are limited studies provide evidence supporting early (Fitzpatrick, 2003; United States Department of settlement in Palau dating back more than United States Department of Agriculture (USDA), N.R.C.S. 2009. Soil Survey of the Island of Palau, Republic of Palau. Agriculture, 2009). Most archeological evidence 3000 years (Liston, 2008). The origin of these is drawn from the Southern Lagoon from settlers is not clear and Palauan settlement may Wickler, S.2002. Oral Traditions and Archaeology: Modeling Village Settlement in Palau, Micronesia. scattered limestone rock islands settlements, have been through several waves of different Micronesian Journal of the Humanities and Social Sciences 1: 39-47. seen in Fig.2. These archeological features and immigration events (Clark, 2005). the ecological significance of these limestone

Fig. 2. UNESCO World Heritage Site delineation (blue line) (Reepmeyer et al. 2011).

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