Innovative PhotoDocumentation Accelerates Botanical Research in Philippine Eagle Forests

Dr. Pieter B. Pelser and Dr. Julie F. Barcelona

Dr. Pieter B. Pelser examining plant species during fieldwork for the botanical documentation.

Philippines, May 2026 — An innovative botanical field research program conducted across several regions of the Philippines has rapidly expanded scientific knowledge of plant diversity in forests that support the critically important habitat of the Philippine Eagle. By emphasizing intensive photodocumentation alongside traditional field methods, the project demonstrated how large volumes of reliable botanical data can be generated efficiently and shared widely in support of conservation and research.

The research team documenting plant specimens in the field as part of the photo-driven botanical study supporting forest and Philippine Eagle habitat conservation.

The research was led by Dr. Pieter B. Pelser, Dr. Julie F. Barcelona, and Forester Guiller Opiso. The team’s approach centered on systematic, high-quality photographic documentation of plants encountered during field surveys. This method allowed many species to be recorded and verified in a relatively short period of time, significantly increasing the scale and impact of the research.

The project had four main aims:

1. to better understand the species composition of forests that are home to the Philippine Eagle;

2. to contribute new plant distribution data to Co’s Digital Flora of the Philippines (CDFP; www.philippineplants.org);

3. to photodocument plant species for which images were previously lacking on CDFP, expanding its value as an identification and research tool for scientists, students, conservationists, local governments, and plant enthusiasts; and

4. to support local conservation efforts in areas where fieldwork was conducted.

   
   

Fieldwork took place in Agusan del Norte, Apayao, Bukidnon, Leyte Province, Surigao del Norte, and Surigao del Sur during November–December 2025 and March–April 2026. Through their photography-driven approach, the team collected more than 27,500 photographs of 2,457 plants, representing approximately 1,800 species—an exceptional output for a relatively short series of field campaigns.

This intensive photodocumentation enabled several major contributions to Philippine botany. The team photographed at least 59 plant species for which no images previously existed on CDFP, directly filling critical gaps in the national flora’s visual records. In addition, 680 species were documented as new provincial records, meaning they had not previously been recorded for those provinces in the CDFP database.

Syzygium multinerve (Myrtaceae), a poorly known and Critically Endangered species photographed in Mun. Pudtol (Apayao Prov.).

“This work highlights just how much remains to be documented in Philippine forests,” said Dr. Pelser. “By making these images openly available, we ensure that the data we collected can immediately support identification, research, education, and conservation.”

“This is critically important because the extent and health of natural ecosystems in the Philippines are rapidly declining,” Dr. Barcelona added. “The Philippines needs better and faster access to plant identification resources than traditional approaches have thus far been able to provide.”

“Robust botanical documentation in Philippine Eagle habitats provides clear, evidence-based justification for forest protection,” said Dennis Salvador, Executive Director of the Philippine Eagle Foundation. “The presence of endemic and threatened plant species demonstrates that conserving the Philippine Eagle and its habitat delivers measurable biodiversity co-benefits. This strengthens its role as both a flagship and umbrella species, supporting science-based conservation policy and investment priorities.”

Dr. Pelser and Dr. Barcelona are researchers at the University of Canterbury, School of Biological Sciences, and are also Research Fellows of the Philippine Eagle Foundation (PEF). Guiller Opiso is a forester with PEF, which played a key role in facilitating the fieldwork and linking the research to on-the-ground conservation efforts.

The research team, consisting of Forester Guiller Opiso, Dr. Julie F. Barcelona and Dr. Pieter B. Pelser.

By combining botanical expertise with intensive photodocumentation, this research highlights an efficient and scalable model for biodiversity studies in tropical forests—one that strengthens open-access scientific resources while directly supporting the conservation of Philippine forests and the iconic species they sustain.

The project was conducted in collaboration with and support from local government units of Burauen, Calanasan, Gigaquit, Hinatuan, Lingig, Pudtol, and San Fernando (Bukidnon); CENRO Bislig; the Provincial Government of Apayao; Caraga State University; Visayas State University; the Hotchkiss family; and Botanic Gardens Conservation International (BGCI). The team also acknowledges the funding partners for the different expedition legs, including the Darwin Initiative (Bukidnon leg), the Mandai Nature Wildlife Loan Agreement Project (Leyte leg), and San Roque Power Corporation together with the local government units of Apayao, Calanasan, and Pudtol (Apayao leg). Field activities were conducted under Gratuitous Permits for Wildlife Collection issued by the Department of Environment and Natural Resources Regional Offices X, VIII, and CAR.

The team also expresses its sincere thanks to Ma. Susana Legaspi, Jayson Ibañez, and Annie Marsha Abayan of the Philippine Eagle Foundation for their continued support.