Journal of Threatened Taxa | www.threatenedtaxa.org | 26 November 2022 | 14(11): 22080-22085

 

 

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print) 

https://doi.org/10.11609/jott.7826.14.11.22080-22085

#7826 | Received 11 January 2022 | Final received 25 August 2022 | Finally accepted 16 October 2022

 

 

 

Status of mangrove forest in Timaco Mangrove Swamp, Cotabato City, Philippines

 

Cherie Cano-Mangaoang 1, Zandra Caderon Amino 2  & Baingan Brahim Mastur 3

 

1 Biology Dept, College of Science and Mathematics, University of Southern Mindanao, Kabacan, Cotabato, Philippines.

2 Cotabato State University, Sinsuat Ave, Cotabato City, 9600 Maguindanao, BARMM, Philippines.

3 Cotabato City National High School-Main Campus, Cotabato City, BARMM, Philippines.

1 ccmangaoang@usm.edu.ph (corresponding author), 2 zandraamino1234@gmail.com, 3 bing55275@gmail.com

 

 

 

 

Editor: R.N. Mandal, Central Institute of Freshwater Aquaculture, Rahara, India. Date of publication: 26 November 2022 (online & print)

 

Citation: Cano-Mangaoang, C., Z.C. Amino & B.B. Mastur (2022). Status of mangrove forest in Timaco Mangrove Swamp, Cotabato City, Philippines. Journal of Threatened Taxa 14(11): 22080–22085. https://doi.org/10.11609/jott.7826.14.11.22080-22085

 

Copyright: © Cano-Mangaoang et al. 2022. Creative Commons Attribution 4.0 International License.  JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

 

Funding: This study is a self-funded research.

 

Competing interests: The authors declare no competing interests.

 

Author details: Cherie Cano-Mangaoang is a faculty member of the University of Southern Mindanao under the Department of Biological Sciences. She is currently working on two research projects funded by the Ministry of Science and Technology and NSTEP-NRCP.  Her field of expertise is biodiversity conservation, plant taxonomy, and ecology. Zandra Caderon Amino The author is an assistant professor at Cotabato State University and a member of the university’s Academic, research, and extension council. Presently taking up a doctor of philosophy in education major in biology at the University of southern Mindanao, Kabacan, Cotabato Philippines.  Baingan B. Mastur is a secondary school teacher teaching grade 9 science at Cotabato City National High School-main campus. She already completed her academic courses for the degree of doctor of philosophy in science education majoring in biology.

 

Author contributions: ZA and BBM—field data collection and processing. CC-M—writing the paper.

 

Acknowledgements: The authors would like to thank the local government units of the three barangays for allowing the researchers to conduct their study in the area.  Thanks, is also extended to Dr. Krizler C. Tanalgo and Dr. Florence Roy P. Salvana for their valuable inputs in improving the paper.

 

 

 

Abstract: Mangrove forests are important coastal ecosystem considering its various ecosystem services.  This study was conducted to generate an updated list and the current abundance of mangrove species in Timaco Mangrove Swamp located in Cotabato City, Bangsamoro Autonomous Region for Muslim Mindanao (BARMM).  Three sampling plots measuring 5 x 40 m were established in three identified sampling sites.  Based on the result of the study, 15 species of mangroves were identified in Timaco Mangrove swamp.  This number of species is higher compared to the previous study wherein 12 species were identified.  With this number of species, seven species were considered new in the area, and five species were not recorded which were identified in the previous study.  A total of 115 individuals were recorded in the present study which indicates a decrease of 79% compared to the previous study.  Furthermore, the present study recorded two threatened species, namely, Aegiceras floridum (Near Threatened) and Avicennia rumphiana (Vulnerable).  Continuous anthropogenic activities were observed in the sampling sites which can be attributed to population decrease.  Thus, the need for immediate local conservation is recommended. 

 

Keywords: Anthropogenic activities, Bangsamoro Autonomous Region, biodiversity, conservation, Mindanao Island, restoration.

 

 

 

INTRODUCTION

 

Mangrove forest, similar to other forest ecosystems, provides an array of ecosystem services that directly and indirectly benefit humans.  Among these, provisioning services is the most common.  It is a good source of timber for construction materials, fuel wood, marine food, and medicine.  On the other hand, regulating services can also be provided which include prevention of floods and erosion, and protection against severe impacts of storms and even tsunamis.  Recently, mangrove forests are also utilized for their aesthetic values which include tourism, and educational activities, among others (Camacho et al. 2020).  Mangrove forests are identified as the main ecosystem that supports life in coastal and marine areas (Suharno & Saraswati 2020).  In 1920, Philippine mangrove is about 400,000–500,000 ha, however, a tremendous decline to 120,000 ha in 1994 was recorded (Primavera 2000) which becomes alarming.

Several studies showed (e.g., Long et al. 2014; Fortes & Salmo III 2017) that a decreasing trend of mangrove forest areas in the Philippines is evident and this is due to environmental and anthropogenic activities (Van Lavieren et al. 2012).  Major factors identified that leads to the destruction of our mangrove ecosystem include the conversion of mangrove areas to fishponds and charcoal production (Eusebio et al. 1986; Primavera 1995; Melana et al. 2005).  Aside from this, the constant increase in population put pressure on our coastal areas which directly and indirectly affect mangrove forests (WIlkie & Fortuna 2003).  Accordingly, the lack of awareness of the community have resulted to exploitation and disturbances on mangrove areas. Dangan-Galon et al. (2016) revealed that increased human population, mangrove deforestation, and improper waste disposal are among of the human-related disturbances which have affected mangrove forests particularly in Puerto Princesa Bay, Palawan, Philippines.  These activities, as indicated by Camacho et al. (2020), will place mangrove ecosystems on the verge of complete collapse.

Timaco mangrove swamp is situated in Cotabato City, Philippines which covers three barangays.  Dimalen & Rojo (2018) conducted a floral assessment in Timaco mangrove swamp wherein they reported low diversity of mangroves in the area.  This result was attributed to anthropogenic activities such as crab hunting, shell picking, timber cutting for charcoal production and conversion to fishpond.  From the year of the first assessment, no studies have been conducted on the remaining species in the area.  Thus, the study was conducted to have an updated checklist of mangrove species including the species’ conservation status in Timaco mangrove swamp and to determine its abundance.  Results of this study can be a useful tool in the effective implementation of policy for the restoration, protection, and conservation of this mangrove forests.

 

 

MATERIALS AND METHODS

 

The study was conducted in June–July 2021 in Timaco Magrove Swamps in Cotabato City, Philippines.  This thin strip of mangrove forest lies within the coordinates of 7.2031 oN, 124.19 oE, 2.1 km (Image 1) within the elevation of 5 m.  The mangrove swamp extends south-west traversing Timaco Hill, one of the highest elevated portions of Cotabato City, Philippines (Dimalen & Rojo 2018). 

The sampling sites considered in the study were mangrove areas of (1) Kalanganan I, (2) Kalanganan II and (3) Kalanganan Mother.  These areas were also the sites of the previous study conducted by Dimalen & Rojo (2018).  Sampling plots were purposively established in the ‘bakawan’-dominated part.  A total of three (3) 5 x 40 m sampling plots were established in each site.  All mangrove species found within each sample plot were identified and counted.  Relative abundance was computed using the formula: Relative abundance = Total # of spp./ total # of spp. population x 100.  Field notes were taken, and preliminary identifications of mangrove species were done on-site.  Morphological characteristics of leaves, flowers, and propagules were noted and used in the confirmation of the identification of species.  Key guides such as the Field guide to Philippine Mangrove by Primavera et al. (2004) and other published work were used to identify samples up to species level if possible.   Samples were photographed for further identification of species.  Anthropogenic activities observed in the sampling site were also noted.

 

 

RESULTS AND DISCUSSION

 

A total of 15 species of mangrove belonging to 10 genera and nine families are identified in Timaco Mangrove swamp.  This number of species is higher compared to the study of Dimalen & Rojo (2018).  Among the 12 species identified in the previous study, eight were still present in the area namely Ceriops tagal, Aegiceras corniculatum, A. floridum, Lumnitzera littorea, Sonneratia alba, S. caseolaris, Rhizophora mucronata, and Xylocarpus granatum.  Moreover, 7 species were newly recorded: Acrostichum aureum, A. speciosum, A. rumphiana, Acanthus ebracteatus, Brugiuera cylindrica, Nypa fruticans, L. littorea, and Rhizophora stylosa (Table 1).

The difference in the number of species identified in this paper compared to that of Dimalen & Rojo (2018) can be contributed to the sampling effort done in this study.  A comprehensive accounting of species was done and did not limit only in the species found within the established sampling plots.  In the identification of species, we used the guides and reference books authored by Primavera et al. (2004), in which A. aureum, A. speciosum, A. ebracteatus, and N. fruticans were listed as mangrove species.  Moreover, the present mangrove species thriving in Timaco mangrove swamp is higher compared with the species identified from various coastal areas in Mindanao including Alabel and Maasim, Saranggani Bay Protected Seascape (Natividad et al. 2014), Butuan Bay, Agusan del Norte (Goloran et al. 2020).  Despite being greatly affected by disturbances observed in the area, Timaco mangrove swamp still harbors a considerable number of species.  This is an indicator that there is a high possibility of restoring the mangrove swamps as a considerable number of saplings have also been observed.

Among the 15 species identified, two (2) have conservation issues, 1 Vulnerable (VU) and 1 Near Threatened (NT).  The Near Threatened species is A. floridum (Image 2A), while the vulnerable is the A rumphiana (Image 2B).  However, three species listed – A. rumphiana, L. littorea, and X. granatum have been categorized as species with decreasing population as recognized by IUCN Red List.  There is a conservation policy towards the area, however, conservation measures for these threatened species are not evident.

A total of 115 mangrove individuals were recorded in the three sampling sites (Table 1).  A. corniculatum had the highest relative abundance of 19.1, followed by N. fruticans with 10.4 and X. granatum has the least with 0.9.  Three species were commonly observed in all three sites—N. fruticans, A. floridum, and B. cylindrica.

There was a decrease of 79% in the total number of individuals in Timaco Mangrove swamps based on the previous study.  Dimalen & Rojo (2018) mentioned that the lower species richness of mangroves in the study site, specifically in Kalanganan I, was due to the aforementioned anthropogenic activities despite the presence of local ordinance.  Moreover, it was observed that there were structures such as houses for human settlement.  These anthropogenic activities along with land conversion to fishponds contribute significantly to the decline of mangrove forests in the Philippines (Dangan-Galon et al. 2016; Buitre et al. 2019).  This decrease will not affect only the biodiversity and ecosystem function of the mangrove forest but also ecosystem services that generally benefited human population (Cardinale et al. 2012) especially those villagers who are dependent on coastal resources (Primavera 2000).  Furthermore, it was observed that mangrove individuals commonly noted as tall with big trunk species have shorter and lesser trunk diameter particularly A. rumphiana.  According to Patindol & Casas (2019), such a condition has resulted from the long history of cutting mangroves.  Individuals of species under the families Avicenniaceae and Sonneratiaceae found in the area were almost multi-stem which must have been restored after heavy cutting in the early years (Image 3).  Efforts have been done to rehabilitate the area using propagules of the Rhizophora species; however, various factors affect the unsuccessful growth towards maturity of the seedlings planted.  During hightide, seedlings were being covered by water hyacinth (abundance of water hyacinth is a perennial problem of the area) which eventually cause the seedlings to die during low tide.  In addition, domesticated animals of the community nearby were observed to feed on the growing plant which inhibits the growth of the propagules.  Though mangrove forest conservation and rehabilitation have captured the interests of various stakeholders, most efforts were unsuccessful due to the lack of science-based approach guidelines (López-Portillo et al. 2017).  Moreover, if rehabilitation strategies employed by other mangrove areas in the southern Philippines will be done in Timaco mangrove swamp such as community involvement and science-based strategy, the rehabilitation endeavor will be successful.  In the case of Katunggan Eco Park situated in Lebak Sultan Kudarat, Philippines policy strengthening in mangrove forest conservation and protection is accompanied by community involvement (Mangaoang & Flores 2019).  Locals were made part in the management of the said mangrove forest such as involvement in the tree-growing activities and delegated as forest guards.

 

 

CONCLUSION AND RECOMMENDATION

 

The significant decrease of mangroves in Timaco Mangrove Swamp calls for immediate action to conserve this important coastal mangrove forest not only on the presence of two species with conservation concerns but the whole mangrove ecosystem which is facing the effects of the unregulated harvest of timber, the establishment of structures and as well as attempts to secure ownership of the part of the area is on its way.  Cotabato City was once hit by an earthquake in the year 1976 and produced tsunami which destroy properties and even lives.  If this mangrove forest will be rehabilitated, this will prevent the greater impact of the aforementioned natural calamity.  Utilization of the remaining individuals of mangrove species in the area can be utilized as a source of propagules in rehabilitating it.  Restoration effort of an almost denuded mangrove forest like of the Timaco Mangrove swamp requires a concerted effort of the government, community, and stakeholders; a sense of ownership must be felt by the community to lessen if not totally eradicated the activities leading to mangrove forest destruction.  Furthermore, a more comprehensive study on the mangrove biodiversity of this area must be conducted to strengthen policy decisions for Timaco mangrove swamp restoration, protection, and preservation.

 

Table 1. An updated list of mangrove species in Timaco Mangrove Swamp.

Family

Species name

Common name

Relative abundance 

Conservation status

Lower vascular plant

 

 

 

 

Pteridaceae

Acrostichum aureum L.

Palaypay

8.7

Least Concern

 

Acrostichum speciosum Willd.

Palaypay

6.1

Least Concern

Flowering plant

 

 

 

 

Acanthaceae

Acanthus ebracteatus Vahl

Lagiwliw

7.8

Least Concern

Arecaceae

Nypa fruticans Wurmb

Nipa

10.4

Least Concern

Avicenniaceae

Avicennia rumphiana (Hallier f.) Bakh.

Bungalon

7.8

Vulnerable

Combretaceae

Lumnitzera littorea (Jack) Voigt.

Tabao, Culasi

4.3

Least Concern

Meliaceae

Xylocarpus granatum J. Koenig

Tabigi

0.9

Least Concern

Myrsinaceae

Aegiceras corniculatum (L.) Blanco

Saging-saging, Tinduk-tindukan

19.1

Least Concern

 

Aegiceras floridum Roem. & Schult.

Saging-saging, Tinduk-tindukan

6.1

Near Threatened

Sonneratiaceae

Sonneratia alba Sm.

Pagatpat

4.3

Least Concern

 

Sonneratia caseolaris (L.) Engl.

Pedada

3.5

Least Concern

Rhizophoraceae

Bruguiera cylindrica (L.) Bl.

Pottan, Busain

9.6

Least Concern

 

Ceriops tagal (Perr.) C.B. Rob.

Tungog, Tangal

1.7

Least Concern

 

Rhizophora mucronata Lamk

Bakhaw babae

3.5

Least Concern

 

Rhizophora stylosa Griff.

Bakhaw bata

6.1

Least Concern

 

 

For images - - click here for full PDF

 

 

REFERENCES

 

Buitre, M.J.C, H. Zhang & H. Lin (2019). The mangrove forest change and impacts from tropical cyclones in the Philippines using Time series satellite imagery.  Remote Sensing 11: 1–15. https://doi.org/10.3390/rs11060688

Camacho, L.D., D.T. Gevaña, L.L. Sabino, C.D. Ruzol, J.E. Garcia, AC.D. Camacho, T.N. Oo, A.C. Maung, K.G. Saxena, L. Liang, E. You & K. Takeuchi (2020). Sustainable mangrove rehabilitation: Lessons and insights from community-based management in the Philippines and Myanmar. APN Science Bulletin 10(1): 18–25. https://doi.org/10.30852/sb.2020.946

Cardinale, B.J., J.E. Duffy, A. Gonzalez, D.U. Hooper, C. perrings, P. Venail, A. Narwani, G.M. Mace, D. Tilman, D.A. Wardle, A.P. Kinzig, G.C. Daily, M. Loreau, J.B. Grace, A. Larigauderie, D.S. Srivastava &  S. Naeem  (2012). Biodiversity loss and its impact on humanity. Nature 486: 59–67. https://doi.org/10.1038/nature11148

Dangan-Galon, F., R.G. Dolorosa, J.S. Sespene & N.I. Mendoza (2016). Diversity and structural complexity of mangrove forest along Puerto Princesa Bay, Palawan Island, Philippines. Journal of Marine and Island Cultures 5: 118–125. https://doi.org/10.1016/j.imic.201.09.001

Dimalen, F.K. & M.J.A. Rojo (2018).  Floral diversity of a mangrove forest in Cotabato City Philippines. Journal of Biodiversity and Environmental Science 13(6): 117–123.

Eusebio, M.A., F.O. Tesoro & D.M. Cabahug (1986). Environmental impact of timber harvesting on mangrove ecosystem in the Philippines, pp. 337–354. In: National Mangrove Committee (ed.). Mangroves of Asia and the Pacific: Status and Management, Natural Resources Management Center, Ministry of Natural Resources, Quezon City, Philippines. https://doi.org/10.1023/B:HUEC.0000019762.36361.48

Fortes, M.D. & S. Salmo (2017). Status of Mangrove Research and Management in the Philippines: Challenges and Opportunities. State of the Mangrove Summit – Technical Presentations 50–60 pp. https://mangroveecology.files.wordpress.com/2017/04/3-6-status-of-mangrove-research-and-management-in-the-philippines_challenges-and-opportunities.pdf

Goloran, A.B., C. Laurence, B. Glenn & M.A. Tricia (2020).  Species Composition, Diversity and Habitat Assessment of Mangroves in the Selected Area along Butuan Bay, Agusan Del Norte, Philippines. Open Access Library Journal 7: e6249.  https://doi.org/10.4236/oalib.1106249

Long, J., D. Napton, C. Giri & J. Graesser (2014). A mapping and monitoring assessment of the Philippines Mangroves Forests from 1990 to 2010. Journal of Coastal Research 30(2): 260–271. https://doi.org/10.2112/JCOASTRES-D-13-00057.1

López-Portillo, J., R. Lewis III, P. Saenger, A. Roval, N. Koedman, F. Dahdouh-Guesbas & V. Riverra-Monroy (2017). Mangrove forest restoration and rehabilitation, pp. 301–345. In: Rivera-Monroy, V.H., S.Y. Lee, E. Kristensen & R.R. Twilley (eds.). Mangrove Ecosystems: A Global Biogeographic Perspective. Springer, Switzerland.

Mangaoang, C.C. & A.B. Flores (2019). Inventory of mangroves in Katunggan Coastal Eco-Park, Sultan Kudarat Province, the Philippines. Bonorowo Wetlands 9(2): 59–64. https://doi.org/10.13057/bonorowo/w90202

Melana, D.M., E.E. Melana & A.M. Mapalo (2005). Mangroves management and development in the Philippines. SEAFDEC Aquaculture Department.

Natividad, E.M.C., A.O. Dalundong, A.B. Patriarca, M.A. Banisil, V.S. Hingabay, B.H.C. Pana, R.C.E. Teofilo, L.E.J. Salvatierra, V. Dagoc & J.H. Jumawan (2014). Correlation of soil and mangrove diversity in selected sites of Alabel and Maasim, Sarangani Province, Philippines. AAB Bioflux 6(2): 145–153.

Patindol, T.A. & E.V. Casas Jr. (2019). Species diversity and composition of mangroves in Tacloban City Philippines. Annals of Tropical Research 41(2): 67–75. https://doi.org/10.32945/atr4126.2019

Primavera, J.H. (1995). Mangroves and brackishwater pond culture in the Philippines. Hydrobiologia 295: 303–309. https://doi.org/10.1007/BF00029137

Primavera, J.H. (2000). Development and conservation of Philippine mangroves: institutional issues. Ecological Economics 35(1): 91–106. https://doi.org/10.1016/S0921-8009(00)00170-1

Primavera, J.H., R.S. Sadaba, M.J.H.L. Lebata & J.P. Altamirano (2004). Handbook of Mangroves in the Philippines-Panay. SEAFDEC/AQD and UNESCO.

Suharno & E. Saraswati (2020). The identification of mangrove ecosystem services for decision making. SHS Web of Conferences 86: 1–7. https://doi.org/10.1051/shsconf/20208601019

Van Lavieren H, M. Spalding, D.M. Alongi, M. Kainuma, M. Clusener-Godt & Z. Adeel (2012). Policy Brief. Securing the future of mangroves. United Nations University, Canada

Wilkie, M.L. & S. Fortuna (2003). Status and trends in mangrove area extent worldwide, Fortuna. Food and Agriculture Organization Forest Resources Assessment Working Paper, 63, Rome. www. fao.org/forestry/mangroves/statistics