Sagip Sarihay Series features critically endangered species in the Philippines, with weekly posts of alternating plant and animal species, and with the primary aims of awareness and call to action. This series is a project of the SciTech and the VA sections of UST-CSJ. (Note: Weekly order of posting does not reflect actual order of intensity of endangerment. Database reference for selection of species is the IUCN Red List.)

SAGIP SARIHAY #2

Species: Pterodroma phaeopygia (Galapagos Petrel)

Words by Cyril Francis
Artwork by Lara Bianca Tordecilla

A visual representation of Galapagos Petrel.

Description

Pterodroma phaeopygia, commonly known as the Galapagos Petrel, are large, long-winged and have an overall dark-gray topside that darkens towards the wings and tail. This avian species is also characterized to be sexually monomorphic or hard to distinguish by sex, and also have a distinct black hood at the sides of the neck (Kennedy et al., 2000). Interestingly, P. phaeopygia are commonly nocturnal and have their night courtship by towering into the sky and flying lively, for such display tends to attract females (Cruz et al., 2010). In relation to other species and to nutrition, these petrels usually take mesopelagic prey including small fish, crustaceans, squids, and other invertebrates, especially at night being the time these prey are at the surface. Interestingly, small bioluminescent prey visible at that time are also part of the petrels’ targets (Ballance, 2004; Imber et al. 1995).

Locality

Usually breeding in Galapagos and Pacific Is., P. phaeopygia had been also observed to breed in Negros Is., Philippines, with the particular subspecies P. phaeopygia sandwichensis Ridgway, 1884 (Pedregosa-Hospodarsky et al., 2009).

Threats

This species has been suffering from the consequences of introduced predators and as well as of agricultural expansion on the petrels’ natural nesting areas, thus causing very rapid decrease in their number. Furthermore, threats to this species are also attributed to the impacts of intrusion of alien invasive species, for these cause impairment on the reproductive success of P. phaeopygia (Cruz et al., 2010). Generally, the consequences brought by predation, along with habitat deterioration produced by other organisms like mammals including rats, cats, pigs, burros and dogs, introduced to the natural habitats of the P. phaeopygia lead to immense decline of these petrels’ natural populations over the years (Patiño et al., 2013).

Solutions to Address Endangerment

According to Salafsky et al. (2008), in a broad sense, ways to address the alarming status of P. phaeopygia are control of invasive species, need for continuous monitoring, studies on genetic diversity and gene flow within and among the species’ colonies, more enhanced breeding area, awareness/education, and harvesting management. Furthermore, the same study also added species recovery through reintroductions, better legislation standards, and assessments of the species status in relation to global warming. In all species having critical status, thus including the P. phaeopygia, Danckwerts (2015) emphasized that it is important to commence and to sustain multi-disciplinary research initiatives to which the management plans of species and colonies should be derived for more effective actions.

References

Ballance, D. K. (2004). Birdwatching from cargo ships. British Birds, 97(1), 16–26.

Cruz-Delgado, F., Wiedenfeld, D. A., & González, J. A. (2010). Assessing the potential impact of wind turbines on the endangered Galapagos Petrel Pterodroma phaeopygia at San Cristóbal Island, Galapagos. Biodiversity and conservation, 19(3), 679–694.

Danckwerts, D. K. (2015). The Trophic Ecology of the Endangered Endemic Barau’s Petrel (Pterodroma Baraui) from Reunion Island, South-western Indian Ocean (Doctoral dissertation, Rhodes University).

Imber, M. J., Jolly, J. N., & Brooke, M. D. L. (1995). Food of three sympatric gadfly petrels (Pterodroma spp.) breeding on the Pitcairn Islands. Biological Journal of the Linnean Society, 56(1–2), 233–240.

Kennedy, R., Gonzales, P. C., Dickinson, E., Miranda Jr, H. C., & Fisher, T. H. (2000). A guide to the birds of the Philippines. Oxford University Press.

Patiño, L., Cruz, M., Martínez, P., & Cedeño-Escobar, V. (2013). Using PCR-RFLP for sexing of the endangered Galápagos petrel (Pterodroma phaeopygia). Genetics and Molecular Research, 12(4), 4760–4767.

Pedregosa-Hospodarsky, M., Hospodarsky, P., Castro, D., Jose, P. F. S., Abalajon, J. M., Alpas, R., & Perez, L. J. (2009). A Faunal Assessment of the North Negros Natural Park (NNNP) Negros Island, Philippines.

Salafsky, N., Salzer, D., Stattersfield, A. J., Hilton‐Taylor, C. R. A. I. G., Neugarten, R., Butchart, S. H., … & Wilkie, D. (2008). A standard lexicon for biodiversity conservation: unified classifications of threats and actions. Conservation Biology, 22(4), 897–911.