Palawan Research Articles

Homalomena brachygyna (Araceae), a new species from Palawan Island, Philippines

Homalomena brachygyna, a new species from the riparian forest of San Vicente, Palawan, is herein described. This novel addition to the Homalomena species of the Philippines bridges the gap of more than 100 years since the last described species from the country. It is also the second endemic Homalomena species in the island of Palawan. Descriptions, photographs, as well as notes on its habitat and ecology, phenology, and preliminary IUCN conservation assessment are provided.

Distribution of total mercury in coastal sediments of Honda Bay, Palawan Island, the Philippines

Honda Bay is considered as one of the mercury hotspots in the world due to its proximity to the abandoned Palawan Quicksilver Mine. In this study, a detailed sediment sampling conducted in between 2021 and 2022 where a total of 166 sediment samples were collected along the coast and analyzed for total mercury (THg) concentration. The study assessed mercury toxicity using the geoaccumulation index and compared Hg levels to sediment quality guidelines. The findings revealed a wide range of THg concentrations, from 0.0040 to 11.4702 mg/kg, with hotspots identified at the Honda Bay wharf and Tagburos River mouth. Mercury spreads to a large coastal area brought by tidal currents and the wave energy actions. The geoaccumulation index indicated moderate to strong Hg contamination in the vicinity of the hotspots and around 24.7–36.1 % of samples exceeded the sediment quality guidelines suggesting adverse biological effects in aquatic biota will frequently occur.

Opening and Closure of the Sulu Sea: Revealed by Its Peripheral Subduction and Collision Processes

The Sulu Sea is a small marginal sea in the western Pacific, but it is a very complex and tectonically active region, situated amidst the convergence of the Eurasian, Pacific, and India-Australian plates. Deciphering its geodynamic evolution is crucial, but our understanding of its opening, closure, and tectonic history remains inadequate. The main aim of this study was to systematically study the opening and subsequent closure of the Sulu Sea though discerning tectonic unconformities, structural features, and subduction-collision tectonic zones around margins of the sea. The interpreted sections and gravity anomaly data indicate that the NE Sulu Sea has undergone Neogene extension and contraction due to subduction and collision along the northern margins of the Sulu Sea, whereas the SE Sulu Sea gradually extended from northwest to southeast during the Middle Miocene and has subsequently subducted since the Middle Miocene along the southeastern margins of the Sulu Sea. Several subduction and collision boundaries with different characteristics were developed including continent-continent collision, arc-continent collision, and ocean-arc subduction. The different margins of the Sulu Sea showed distinct asynchronous subduction and collision processes. The northern margins of the Sulu Sea can be divided into three subduction-collision tectonic zones from west to east: the Sabah-Nansha block collision has occurred in NE Borneo since the Early Miocene, followed by the SW Palawan-Cagayan arc collision in SW Palawan Island since the Middle Miocene, and the NW Palawan-Mindoro arc collision since the Late Miocene with further oblique subduction of the Philippine Sea Plate. The southeastern margins can also be divided into two subduction tectonic zones from south to east: the SE Sulu Sea has subducted southward beneath the Celebes Sea since the Middle Miocene, followed by the southeastward subduction beneath the Philippine Sea Plate since the Pliocene. Since the Miocene, the interactions among the Australia-India, the Philippine Sea, and the Eurasian plates have formed the circum-Sulu Sea subduction-collisional margins characterized by microplate collisions, deep-sea trough development, and thick sediments filling in the orogenic foreland. This study is significant for gaining insights into the opening and closure of marginal seas and the dynamics of multiple microplates in Southeast Asia.

Psychotria pendens (Rubiaceae, Psychotrieae), a new ultramafic species from Central Palawan, Philippines

Psychotria pendens from the lowland ultramafic forest of Mt. Victoria, Palawan Island, Philippines is herein described as a new species of Rubiaceae. The new species is morphologically similar to P. rubiginosa (Gitingensis species group) by having monochotomous inflorescence and oblanceolate to oblong-elliptic leaves but is distinguished by its large, leaf-like, valvate stipules with biattenuate to biacuminate tips, pendent inflorescence, glabrous abaxial leaf surface, narrowly triangular bracts, and glabrous calyx. Molecular analysis revealed that this newly discovered species belongs to the Pacific Psychotria clade, and is allied to the Philippine species P. luzoniensis and Hawaiian species P. mariniana. The species is assessed as Critically Endangered (CR) based on the IUCN Red List categories and criteria.

Plastic litter assessment of the riverbanks of Pulot River and its tributary in Sofronio Española, Palawan Island, Philippines

Rivers are essential sources of plastic litter in the marine environment. Recently, the Philippines was reported as the biggest polluter of plastic litter from riverine sources. However, the riverine plastic litter's origin has been less established. In this study, we determined the density, composition, and accumulation of plastic litter on the riversides of Pulot River and its tributary in Palawan Island, Philippines. We also identified the possible sources of plastic litter. Results showed that the plastic litter density was highest at the river edge during the first sampling period. Litter densities for the predefined zones and sampling periods all showed no significant differences. The most dominant plastic litter types were food packaging and plastic bags, followed by toiletries. ‘Others’ consisted of multilayers, mixed, and plastics accounted for the most abundant polymer types. We identified the residents in the vicinity illegally dumping litter, for there were small illegal dumping sites along the river. These results suggest the urgent need for better waste policy implementation measures to protect the riparian environments and reduce the input of riverine plastic litter into the marine environment to ensure river resource sustainability.

Shopping in the Rainforest: Provisions of Uneven Living at the Sari-Sari Store

This article examines how patron-client relationships deepen into relations of pity, obligation, and dependency through rural neighbourhood stores. Based on ethnographic research on Palawan Island, I examine relations between Tagbanua and their store-owning neighbours in order to consider firstly, how social differentiations of class and ethnicity are reproduced through stores, and secondly, the role of these stores in the reproduction of contending moral claims regarding the foundational basis of this inequality. I suggest that what is being debated can be understood in terms of a right to provision. In drawing on this case study, I argue that the right to provision allows us to consider how the right to provide is bound within claims about the right to be provided with the conditions that make viable provision possible. Shopping in the rainforest, therefore, concerns the moral claims central to how a person can make a living and live with others.

New genera, species and subspecies of tessaratomine true bugs(Heteroptera: Tessaratomidae, Tessaratominae).

The genus Oukhypencha gen. nov. is described to accommodate Hypencha ophthalmica Stl, 1863, and three new species, O. clemenceae sp. nov., O. florenceae sp. nov., and O. stali sp. nov. A new subspecies, O. ophthalmica sumaterensis ssp. nov. is described from Sumatra. The genus Homoiacoris gen. nov. is created for a new species of tessaratomine true bug from Palawan Island in the Philippines, H. annemarieae sp. nov.. Habitus, male and female genitalia are illustrated. The general aspect of the new genera is similar to that of Hypencha Amyot & Serville, and the main diagnostic characters are found in the genitalia. Keys to genera of the sub-tribe Tessaratomina and species of Oukhypencha are given.

RHODODENDRON ASTROPHORUM (ERICACEAE, RHODODENDRON SECT. SCHISTANTHE), A NEW MICRO-ENDEMIC SPECIES FROM CENTRAL PALAWAN, PHILIPPINES

A new micro-endemic species of Rhododendron is described and illustrated from botanical expeditions to the Victoria-Anepahan Mountain Range on the island of Palawan. It closely resembles Rhododendron wilkiei but differs in having leaves with laminae that are narrowly elliptic-oblanceolate, have adaxially indistinct venation, and are arranged in 4–8 active and mostly terminal pseudowhorls along the length of the stem; bracts without scales on the margin; yellow flowers with a red corolla tube interior that is densely hairy towards the base; and hairy anther filament bases. Morphological and geographical data place the species in Rhododendron sect. Schistanthe. The new species, together with a first record of Rhododendron vidalii on Palawan as part of this research, represent the tenth and eleventh members of this genus recorded from the island. A revised key to the Palawan species of Rhododendron is provided.

Orthotrichaceae (Musci) of Palawan Island, with two species new to the Philippines

This paper provides an updated list of the Orthotrichaceae occurring in Palawan Island, the Philippines. Nine species are reported as new to the island. Macromitrium clemensiae E.B.Bartram and M. megalocladon M.Fleisch. are new country records, while the remaining seven species were previously reported in other islands of the Philippines. A key to the species of Orthotrichaceae in Palawan is provided. Descriptions and illustrations are provided for the two new country records. Notes and range extensions for each species reported are discussed.

Metals and Metalloid Concentrations in Fish, Its Spatial Distribution in PPC, Philippines and the Attributable Risks.

Fish is an important source of protein in human meals around the world. However, the fish that we are eating may be contaminated with toxicants such as metals and metalloids (MMs), which may pose health risks to consumers. Information on MMs content in fishes and their potential spatial distribution scenarios would provide knowledge to the community to create strategies and protect human health. Hence, this study assessed and determined the health risk levels of MMs in both brackish and marine water fish (BMF) in Puerto Princesa City (PPC), Palawan Province, Philippines. PPC has an existing abandoned open mine pit near the PPC coastline called the "pit lake". The concentrations of As, Ba, Cu, Fe, Mn, Hg, and Zn in fishes were analyzed using portable Olympus Vanta X-ray Fluorescence (pXRF), and the spatial distribution of MMs concentrations in BMF was analyzed using a GIS (geographic information system). Fishes were sampled from fishing boat landing sites and nearby seafood markets. The results revealed that the concentration of MMs in marine fish was generally higher than the brackish water fish. It was recorded that the Hg concentration in marine water fish meat was higher than in brackish water fish meat. The Mn concentration in marine water fish exceeded the permissible limits set by international bodies. An elevated concentration of Mn in BMF was detected across the northern part of PPC, and an elevated concentration of Hg in marine fishes was recorded in the southeast area, where the fish landing sites are located. Ba was also detected in BMF across the southern part of PPC. Moreover, an elevated concentration of Cu was detected in MBF in the northeast and in marine fish in the southeastern area of PPC. Further, this paper elaborates the non-carcinogenic and carcinogenic risks of these fishes to the PPC population and tourists with respect to the MMs content in fish meat.

TOURIST RESOURCES AND TOURIST POTENTIAL OF MINDORO ISLAND IN THE PHILIPPINES

The article is devoted to the study of the tourism potential of Mindoro Island in the Philippines. The total area of Mindoro Island, which is in the Luzon islands group, is 10571.8 km2 and the total population of the island is 1,4 million. Mindoro, the seventh largest island in the Philippines, is a mountainous and rugged island. The Mindoro Island, situated in the triangle formed by Luzon, Palawan and Panay islands, is one of the most visited and most popular tourism centers of the Philippines. In this study, the geographical location, natural and human geographical features of the island of Mindoro, as well as the tourist attractions and tourism advantages are briefly discussed. The main purpose of the study is to acquaint a wide range of readers with tourism resources, tourism potential, natural and cultural tourist attractions of Mindoro Island and offer new options for recreation for curious tourists. The paper provides a multivariate analysis of tourism on the island by discussing the tourism advantages and disadvantages of Mindoro Island. As a result of the study, the authors have prepared a useful tourist guide for foreign tourists who will visit the island. It was revealed that Mindoro Island is not as big as Luzon, it is not as crowded as Mindanao, it does not have as many luxurious tourist spots as Boracay, and it cannot be said that it is a famous tourist destination like Palawan Island. However, this tropical island attracts thousands of holidaymakers from all over the world every year due to its unique natural beauty and breathtaking tourist attractions. Mindoro Island can offer an alternative travel option, an exciting travel itinerary and an interesting travel destination for every curious tourist 365 days a year.

Revisiting environmental management zones toward conserving globally important species in western Philippines

The establishment of environmental management zones is an important strategy for biodiversity conservation. However, identifying and assigning appropriate zones is a challenging task that is critical to the management’s success. The Environmentally Critical Areas Network (ECAN) of the Palawan province is among the management strategies being implemented in the western Philippines. Under this strategy, natural resources needing the highest degree of protection are designated as core zones (CZ). Our study revisited this strategy to assess the current placement of the core zones with respect to species distributions and vegetation types. We conducted a series of field surveys in four municipalities of Palawan to assess the status of biodiversity. Gathered data was used to identify potential critical habitats by generating species distribution models and performing vegetation analysis using land satellite images. The placement of the CZ was evaluated using the identified critical habitats. Our assessments show that many Palawan endemic species persist despite increasing pressures from anthropogenic activities. We also found that a considerable extent of natural forest remains, generally confined in high elevations and steep terrains. The assessment of critical habitats and CZ revealed vital gaps in protection, suggesting that a revision is necessary to accommodate important habitats of threatened and endemic species. Overall, our study highlights the significance of integrating biodiversity data in improving conservation and management strategies, which has been overlooked in the current ECAN zones.

Strategic Implementation of Integrated Water Resource Management in Selected Areas of Palawan: SWOT-AHP Method

In the recent past, Integrated Water Resource Management (IWRM) has emerged as the method of choice for resolving a wide range of water-related conflicts that arise between governments and stakeholders all over the globe. Despite a variety of regulations and initiatives being put into place, there is still skepticism over their actual execution. In 2006, the Philippine government began updating the water policy and regulatory framework to promote IWRM as a foundation for sustainable development. However, implementation of this national and subnational structure is still in process. This study intends to identify and rank the key elements likely to affect IWRM changes at the subnational level in Palawan Province. Specifically, this study aims to identify the elements that might improve the result of adopting IWRM, which is as important as designing policies, institutions, and instruments for putting the approach into action. This approach combined the Strengths, Weaknesses, Opportunities, and Threats (SWOT) and Analytic Hierarchy Process (AHP) techniques, a hybrid multi-criteria decision procedure, SWOT-AHP. Expert group discussion revealed the essential elements impacting IWRM implementation in this research, and these elements were categorized into SWOT categories. The AHP approach was used to determine the relative relevance of each component identified in the SWOT analysis. The results show that the following ranking groups have a higher priority for Puerto Princesa: threats (group weight 48.8%), strengths (35.4%), weaknesses (10.7%), and opportunities (5.1%). The ranking group for Roxas is the following: opportunities (36.8%), strengths (27.4%), weaknesses (21.5%), and threats (14.3%). Taytay has the following ranking group: opportunities (27.9%), weaknesses (27.1%), threats (24.7%), and strengths (20.3%). While El Nido has the following ranking group: strengths (33.5%), weaknesses (24.3%), opportunities (24%), and threats (18.2%). This research identified and prioritized the key components essential to the effectiveness of the IWRM concept in the research sites. This study recommends evaluating IWRM implementation using the upgraded element framework, enhancing the strategic framework to assess state, federal, and local IWRM governance performance.

Drivers Of Deforestation And Forest Degradation In Palawan, Philippines: An Analysis Using Social-Ecological Systems (SES) And Institutional Analysis And Development (IAD) Approaches

Palawan Island is home to one of Southeast Asia’s largest, oldest, and most diversified rainforests hence it was called the «Last Frontier.» However, the island province’s forest is contending with increased conversion of forest lands to plantation and household-level agriculture, intensive mineral mining, illegal logging, and other pressures on its ecosystems. Understanding these factors in relation to the prevalence of deforestation and forest degradation in Palawan is imperative. This paper analyzed these drivers of deforestation and forest degradation in Palawan using the social-ecological systems (SES) and institutional analysis development (IAD) frameworks. A literature review was conducted using a variety of web-based databases and sources and additional data were collected from official websites and reports. The identified major drivers of deforestation and forest degradation in the province include increasing population, migration from lowland to upland areas, illegal logging, mining, wide-scale kaingin and oil palm plantation, wildlife poaching, and weak policy implementation and enforcement. These identified drivers can be the target of the government of Palawan for their forest management plans. Additional findings and recommendations of this paper will also aid in the forest management planning in Palawan and other areas where similar settings exist.

Automating violence? The anti-politics of ‘smart technology’ in biodiversity conservation

This article examines the politics of emerging partnerships among big-tech corporations, big international non-governmental organisations (BINGOs) and bilaterals that promote the uptake and implementation of ‘smart technologies’ in biodiversity conservation. Despite growing global recognition of Indigenous and local peoples' rights to forests, lands, and oceans as central to socially just and successful conservation, new initiatives to conserve 30% of the Earth's territory by 2030 (‘30 × 30’) under the United Nations' (UN) post-2020 Global Biodiversity Framework largely continue to neglect their existing customary rights and uses of biodiverse territories. The consequences of this have become evident in new global conservation partnerships that are taking a ‘technological turn’. ‘Smart technologies’ that rely on artificial intelligence (AI) and complex hardware, such as camera traps, drones, and smartphones, enable new forms of surveillance and securitisation through and beyond conventional conservation practices. Despite their potential to exacerbate social injustices against historically marginalised groups, the situated character of smart technology impacts and outcomes often remain unquestioned by mainstream conservation actors. Our paper shows how the dominant discourses framing such technology as successful and innovative across global and local partnerships belies its potential to: 1) inflict considerable violence upon local and Indigenous peoples; and 2) neglect the main political economic drivers of biodiversity loss. Drawing on examples from Palawan Island, the Philippines, we show how these global-local governance partnerships have valorised the potential success of smart technology for biodiversity conservation in situ without considering how they may adversely impact Indigenous and local peoples' rights and livelihoods, while at the same time neglecting and depoliticising the violence of capitalist extractivist expansion.

Settlement traps and harvesting methods for spiny lobster (Panulirus spp.) puerulus fishery in Palawan Island, the Philippines

The attractive price for spiny lobster (Panulirus spp.) puerulus has recently encouraged many fishers to engage in its collection as an alternative livelihood at the height of the COVID-19 pandemic. This booming fishery prompted the investigation of the settlement traps, luring/shading materials, trap installation and harvesting methods, and problems encountered in the spiny lobster puerulus fishery in Palawan, Philippines. Reviewed videos posted on social media, personal observation, and data gathered from key informants (KIs) revealed the use of various modified and newly developed settlement traps. The most common were the concrete cylindrical and disc-shaped traps used by 63.33% of the KIs. Some KIs (40%) provided the settlement traps with luring/shading materials like Sargassum thalli. Settlement traps were mostly installed using the stake-hanging method. The harvesting season starts in March and ends in August where the daily collection coincides with the moon phase. Fishers collected settled puerulus through diving or pulling the traps out of the water. However, some issues like unstable prices and the absence of fishing regulations threaten the sustainability of pueruli collection. Hence, the establishment of collection zones, issuance of fishing permits, price regulation, and long-term monitoring to maintain this promising fishery industry is suggested in crafting ordinances. Efficiencies of traps may also be investigated as an additional basis for policy recommendations.

Molecular data from the holotype of the enigmatic Bornean Black Shrew, Suncusater Medway, 1965 (Soricidae, Crocidurinae), place it in the genus Palawanosorex.

Although Borneo has received more attention from biologists than most other islands in the Malay Archipelago, many questions regarding the systematic relationships of Bornean mammals remain. Using next-generation sequencing technology, we obtained mitochondrial DNA sequences from the holotype of Suncusater, the only known specimen of this shrew. Several shrews collected recently in Sarawak are closely aligned, both morphologically and mitochondrially, with the holotype of S.ater. Phylogenetic analyses of mitochondrial sequences indicate that the S.ater holotype and new Sarawak specimens do not belong to the genus Suncus, but instead are most closely related to Palawanosorexmuscorum. Until now Palawanosorex has been known only from the neighboring Philippine island of Palawan. Additional sequences from nuclear ultra-conserved elements from the new Sarawak specimens strongly support a sister relationship to P.muscorum. We therefore transfer ater to Palawanosorex. The new specimens demonstrate that P.ater is more widespread in northern Borneo than previously recorded. Continued sampling of Bornean mammal diversity and reexamination of type material are critical in understanding the evolutionary history of the biologically rich Malay Archipelago.

A virtual paradise? Platform algorithms, coastal change, and the production of nature in the Philippines

Across parts of Southeast Asia, coastal governance strategies have drawn on ‘ecotourism’ initiatives for ‘sustainable development’ by constructing captivating imaginaries of coastal places and people as sites of touristic production and consumption. Increasingly, representations of exotic and pristine coastal natures are reproduced virtually in support of this campaign through Web 2.0 platforms and their underlying algorithms. As ecotourism expands in the region, growing networks of social media users coproduce and consume abstract virtual natures with profound consequences for coastal peoples and ecosystems. In particular, Instagram, a popular photo sharing social media platform, has become central to reifying and distorting complex coastal realities. Drawing on a case from El Nido, Palawan Island, the Philippines, our paper examines how the virtual representation of coastal places and people on Instagram accelerate coastal transformations. Our results reveal how the political economy of coastal governance and the platform capitalism of social media converge to accelerate ecotourism in ways that realign virtual ideals and material realities. As virtual imaginaries shape coastal realities, new forms of exclusion and misrepresentation of people and places drive the displacement of local fishers, violence against activists, and coastal degradation. Bringing together research exploring (mass) ecotourism, platform capitalism and virtualism, we argue that greater scholarly attention should be placed on how new digital actors and platform algorithms influence how coastal peoples and places are imagined, consumed and subject to violence over time.

Studies on the genus Chrysodema (Coleoptera: Buprestidae: Chrysochroinae) part II.

The second part of the study on the genus Chrysodema Laporte de Castelnau & Gory, 1835 is presented. All taxa are revised based on a comparative study of extensive material including types of all described taxa. Chrysodema (Chrysodema) eximia 'complex' is revised and the new C. antennata species-group is established in the subgenus Chrysodema s. str. Two new species and one new subspecies are described: Chrysodema (Chrysodema) holynskii sp. nov. from Philippines: Masbate Island; Chrysodema (Chrysodema) sekerkai sp. nov. from Indonesia: Bangkai, Peleng and Sulawesi islands; and Chrysodema (Chrysodema) antennata barriesi subsp. nov. from Philippines: Palawan Island. Lectotypes are designated for the following taxa to ensure their correct application and recognition in future: C. (C.) antennata Saunders, 1874; C. (C.) hebes Kerremans, 1892; C. (C.) intercostata Saunders, 1874 and C. (C.) obsoleta J. Thomson, 1879. All herein included taxa are illustrated with colour photographs of habitus and the male aedeagus. Keys and maps of distribution to all taxa in each revised species-group are presented.

Notes on the life history of Tirumala septentrionis palawana Fruhstorfer 1899 (Lepidoptera: Nymphalidae: Danainae) from Palawan Island, Philippines

The immature stages of the butterfly Tirumala septentrionis palawana Fruhstorfer 1899 are described and illustrated from specimens observed in El Nido, Palawan Island, Philippines.