Mohamed bin Zayed Species project number 210527045

Distribution, ecology, and conservation of Drepanolejeunea bakeri Herzog, an endangered epiphyllous liverwort from the Philippines

Drepanolejeunea bakeri was described by Herzog in 1930 based on sterile specimens growing on leaves of Ficus validicaudata collected by C.J. Baker at the summit of Mt. Makiling [1, 2]. The occurrence of this species in Mt. Makiling and Mt. Polis was reported by Tixier in 1972 [3] and in Mt. Bulusan by Mizutani in 1975 [4]. Like other epiphyllous bryophytes, this species is highly vulnerable to changes in microclimatic conditions [5]. According to the IUCN SSC Bryophyte Specialist Group in 2000 [6, 7], this species is classified as Endangered (B1, 2cd) with its area of occupancy being less than 500km² with fewer than five localities and its declining habitat. The threats cited are extensive logging and agricultural expansion. In the Philippines’ updated national list of threatened plants [8], this species was classified as Endangered; however, this was merely adopted from the IUCN Red List and no field studies were conducted.

It is apparent that information on the occurrence and distribution of this species needs to be updated as there had been drastic changes in habitat quality and habitat destruction in the identified localities over the past 20 years. The near deforestation of Mt. Polis [9] and the eruptions of Mt. Bulusan [10] may have negatively affected its population in these localities; only the montane rainforests of Mt. Makiling has experienced little to no disturbance. The target outcomes of this project will provide essential information on the current distribution, ecology, and threats on this species which are necessary in updating its conservation status.

Generally, this project aims to provide information on the distribution and ecology of Drepanolejeunea bakeri in Mount Makiling Forest Reserve which are necessary in updating its assessment information and in drafting action plans for its conservation. Specifically, this project aims to:

• conduct field studies and bryophyte collection work in the tropical rainforests of Mt. Makiling and vicinity using modified belt transects and Floristic Habitat Sampling;
• analyze the distribution pattern of Drepanolejeunea bakeri and its relation to environmental parameters such as air temperature, relative humidity, and light intensity;
• identify current and potential threats to the species and its severity;
• disseminate information on the conservation of the tropical lower and tropical upper montane rainforests of Mt. Makiling through communication, education, and public awareness (CEPA) materials; and
• propose the establishment of Permanent Biodiversity Monitoring Areas (PBMAs) for the effective conservation and monitoring of this species in Mount Makiling Forest Reserve.

Literature Cited

[1] Herzog, T. 1930. Studien über Drepanolejeunea I. Annales Bryologici 3:126-149.

[2] Herzog, T. 1931. Hepaticae philippinenses a cl. C. J. Baker lectae. Annales Bryologici 4:79-94.

[3] Tixier, P. 1972. Mount Maquiling bryoflora (Luzon). The Gardens' bulletin, Straits Settlements 26:137-153.

[4] Mizutani, M. 1975. Epiphyllous species of Lejeuneaceae from the Philippines. Journal of the Hattori Botanical Laboratory 39:255-262.

[5] Pócs, T. 1996. Epiphyllous liverwort diversity at worldwide level and its threat and conservation. Anales Inst. Biol. Univ. Nac. Autón. Mexico, Ser. Bot. 67(1): 109-127.

[6] Hallingbäck, T. & N. Hodgetts (compilers). 2000. Mosses, liverworts, and hornworts. Status Survey and Conservation Action Plan for Bryophytes. IUCN/SSC Bryophyte Specialist Group. Switzerland and UK: IUCN.

[7] Bryophyte Specialist Group. 2000. Drepanolejeunea bakeri. The IUCN Red List of Threatened Species 2000: e.T39238A10178412. https://dx.doi.org/10.2305/IUCN.UK.2000.RLTS.T39238A10178412.en.

[8] Department of Environment and Natural Resources. 2017. DENR Administrative Order No. 2017-11: Updated National List of Threatened Philippine Plants and their Categories.

[9] Collar, N.J. et al. 1999. Threatened birds of the Philippines: the Haribon Foundation/BirdLife International Red data book. Philippines: Bookmark.

[10] Global Volcanism Program. 2013. Bulusan (273010) in Volcanoes of the World, v.4.10.0 (14 May 2021). Venzke, E. (ed.). Smithsonian Institution. https://volcano.si.edu/volcano.cfm?vn=273010.