Benjamin M. Vallejo, Jr., Ph.D.
Professor 7
Contact(s): or
Educ. Background:
Ph.D. Marine Biology, James Cook University, Australia (2003)
Manila University, Research Associate, International Centre for Living Aquatic Resources
Management (now WorldFish) (1993-1997)
Professional Aquarist, Aquarium Science Association of the Philippines, Inc, (1992-)
Master of Statistics (University of the Philippines Diliman)
MSc Marine Science (University of the Philippines, Diliman)
BSc Fisheries (University of the Philippines in the Visayas)

Interests / ProjectsCourses Handled & Other InformationPublication


  • Marine biological invasion
  • Biogeographic theory and modelling
  • Community ecology
  • Ecological history and palaeoecology
  • Molluscs
  • Urban environments and bird communities
  • Postnormal science advice and government science policy
  • History of Science in the Philippines and STS

Research Projects:

  • Assessing Manila South Harbor using a science informed Safe Risk Area (SRA) approach in support of Philippine obligations to the Ballast Water Management Convention (BWMC)
  • Antonio Luna doctoral thesis on malaria and Filipino science at the end of Spanish colonial rule in the Philippines
  • Climate envelope models for milkfish, Chanos chanos Forsskål
  • Ecological diversity of fouling organisms in Manila Bay
  • Ecological dynamics of the invasive mussel Mytilopsis (Bivalvia, Mytiloidea) in Manila Bay
  • Thermal ecology and biogeography of intertidal invertebrates used in subsistence fisheries.
  • As co-proponent: The Palaeoenvironment of Mindoro Island, Philippines
  • Baseline studies on Marine non-indigenous species in Manila Bay and ASEAN Ports
  • Urban ecological network for the University of the Philippines Diliman campus-Funded by the University of the Philippines
  • Invasion biology and ecology of an armoured catfish in a Philippine River-Funded by the University of the Philippines
  • Methods for assessing ecological health of Philippine beaches
  • Effects of plastic solid waste in a tropical sandy shore ecosystem

Courses Teaching:

  • Env. Sci. 1 (Environment and Society)
  • Env. Sci. 211 (Computational Methods in Environmental Science)
  • Env. Sci. 297 (Special Topics in Environmental Science)
  • Env. Sci. 299 (Independent Masters Study)
  • Env. Sci. 399 (Independent Doctoral Study)

Other Relevant Information:

Membership in scientific organizations:

  • President-Aquarium Science Association of the Philippines
  • Member-International Coral Reef Society
  • Member-Philippine Association of Marine Science
  • Member-Asian Fisheries Society


  • Inaugural awardee for Science Advice International Network for Government Science Advice-Asia (2019)
  • Distinguished Alumni Awardee for Environmental Rehabilitation and Management – UP Alumni Association (2019)
  • Best scientific paper award National Academy of Science and Technology (2019)

Recent Publication:

  1. Vallejo, B. M., Aloy, A. B., Ocampo, M., Conejar-Espedido, J., & Manubag, L. M. (2019). Manila Bay Ecology and Associated Invasive Species. In Impacts of Invasive Species on Coastal Environments (pp. 145-169). Springer, Cham.
  2. Vallejo, B (2017) Antonio Luna, science and the emerging Filipino national identity, Diliman Review 6(1)
  3. Vallejo B, Conejar-Espedido, J. Manuban L. (2017) The Ecology of an incipient marine biological invasion: The Charru mussel Mytella charuana d’Orbignyi 1846 (Bivalvia: Mytilidae) in Manila Bay, Luzon, Philippines. Phil. J. Sci 146(4):485 – 494
  4. Vallejo B, Conejar-Espedido, J, Manubag, L., Artiaga, KC, Damatac II AM,Imperial IC, Itong, AB, Fontanilla, IK (2017) First record of the Charru mussel Mytella charuana d’Orbignyi 1846 (Bivalvia: Mytilidae) from Manila Bay, Luzon,Philippines Bioinvasions Records 6 (1): 49-55
  5. Jumawan JC, Herrera AA, Jumawan, JH, Vallejo Jr B (2016) Size structure and reproductive phenology of the suckermouth sailfin catfish Pterogoplichthys disjunctivus (Weber 1991) from Marikina River, Philippines. ARPN Journal of Agricultural and Biological Science 11(1): 18-23
  6. Ocampo, MA, Oliva IW, Tan R, Sia Su G, Vallejo BM Jr, Manubag L, (2014) Assessing the Marine Fouling Community in a Man-made Marina at Manila Bay. Advances in Environmental Biology 8(13): 597-601
  7. Jumawan JC, Herrera AA, Vallejo Jr B (2014) Embryonic and larval development of the suckermouth sailfin catfish Pterygoplichthys pardalis from Marikina River, Philippines. Eurasia J Biosci 8: 38-50.
  8. Ochoa, J, Paz V, Lewis H, Carlos J, Robles R, Ferreras R, Lara M, Vallejo, B Jr, Velarde, G, Villaluz, SA, Roqnuillo W, Solheim W III (2014) The archaeology and palaeobiological record of the Pasimbahan-Magsanib site, Northern Palawan. Philippine Science Letters 7(1) 22-36.
  9. Vallejo B, Aloy A (2014) Responses of the bird community in the University of the Philippines Diliman after campus redevelopment and the decline of two common urban bird species. Philippine Science Letters 7(1) 51-56.
  10. Pawlik, A., Piper P, Faylona P, Padilla Jr. S, Carlos, J, Mijares A, Vallejo Jr B, Reyes M, Amano N. 2014. Preliminary Studies on Island Adaptation and Foraging Strategies in Changing Environments from Terminal Pleistocene to Early Holocene in the Philippines: Excavations at Bubog 1 and 2, Ilin Island,Mindoro Occidental. Journal of Field Archaeology
  11. Vallejo BMJ, Aloy AB. 2014. Responses of the bird community in the University of the Philippines Diliman after campus redevelopment and the decline of two common urban bird species. Philippine Science Letters
  12. Jumawan JC, Vallejo BM.2011. DNA barcodes of the suckermouth sailfin catfish Pterygoplichthys (Siluriformes: Loricariidae) in the Marikina River system, Philippines: Molecular perspective of an invasive alien fish species. Philippine Science Letters Philippine Science Letters.4(2)
  13. Aloy AB, Vallejo Jr BM, Juinio-Meñez MA. 2011. Increased plastic litter cover affects the foraging activity of the sandy intertidal gastropod Nassarius pullus. Marine Pollution BulletinMarine Pollution Bulletin. 62. pp. 1772-1779
  14. Vallejo, B (2005) Inferring the mode of speciation in Indo-West Pacific Conus (Gastropoda: Conidae). Journal of Biogeography, 32(8): 1429-1439
  15. Vallejo, B (2004) Biogeography of a sandy shore gastropod, Oliva in the Philippines. Loyola Schools Review 3:58-80
  16. Vallejo, B and Gayos, G (2002). The effect of light intensity on Corallimorph Discosoma fragment growth and recovery under aquarium conditions. J. of Maquaculture. 7:1-5
  17. Reyes, M. and Vallejo, BM (2002) Diet of the intertidal seastar Archaster typicus in Calatagan, Batangas. Loyola Schools Review.
  18. Vallejo, B, Vallente-Samonte R, Chua, L and Panlilio, R. Genetic variation and taxonomic separation in Oliva(Neogastropoda:Olividae) species from the central Visayas, Philippines using a single marker (Marine Biotechnology)
  19. Vallejo, B (2001) The Biogeography of Philippine marine molluscs. Loyola Schools Review 1: 58-77.
  20. Vallejo B (2000) A new species of Nerita from the Sibuyan Sea, central Philippines, La Conchiglia 22: 23-27.