Jamie Dichaves reports on the talk given by Dr. Juan Carlos T. Gonzales “Evolution, Ecology and Ethno-Ornithology as Tools for Conservation: A Study of Hornbills” during a Café Scientifique event hosted by UP Los Banos Department of Science and Communication.
—
Evolution, Ecology and Ethno-Ornithology as Tools for Conservation: A Study of Hornbills – a Talk by Dr. Juan Carlos T. Gonzales.
by Jamie Dichaves
with special thanks to Dr. Juan Carlos T. Gonzalez
Event Background
University of the Philippines – Los Banos’ (UPLB) Department of Science and Communication (DSC), headed by Chairperson Garry Montemayor, under the College of Development Communication (CDC) celebrated its Science Communication (SciCom) week, which started last March 3 and will end on March 8, 2014. The theme for this year’s celebration is “SciC4D 2014: SciCom Goes Green” which focused on environmental, risk, and disaster communication. Dr. Juan Carlos Gonzalez’ “Green Speak” is the first-ever Café Scientifique session held in the Philippines. According to the site, a Café Scientifique “is a place where, for the price of a cup of coffee or a glass of wine, anyone can come to explore the latest ideas in science and technology”. Sessions are held in any place outside of a traditional academic context such as parks, theaters, restaurants, bars, and of course, cafes.
Part of DSC’s goals is to reach out to the general public and make science more accessible to everyone. Having a Café Scientifique helps them reach that goal as sessions are aimed at having scientists and non-scientists talk about science in a relaxed setting.
The Speaker
Fellow Wild Bird Club of the Philippines (WBCP) member and UPLB professor Dr. Juan Carlos “JC” Gonzalez was the speaker for this event. He received his BS and MS degrees in zoology in UPLB and his D. Phil in Zoology/Animal Biology from the University of Oxford. In 2011, he was awarded as one of the National Academy of Science and Technology’s (NAST) Outstanding Young Scientist for his important contributions in biodiversity research and conservation in the Philippines. His main fascination is on hornbills and as such, it has become the focus of his study. His research on birds of the Polillo Islands in Quezon province encouraged the residents to recognize the Polillo Tarictic Hornbill (Penelopides manillae subnigra) as an endemic flagship species and a symbolic part of their natural heritage.
Hornbill Facts
There are 61 known species of hornbills in the world, which come from tropical Africa and Asia (Gonzalez et al. 2013). Sixteen percent (16%) of this (or 10 species) is found only in the Philippines. They all belong to the avian order Bucerotiformes, which includes family Bucerotidae, typical hornbills, and family Bucorvidae, the ground hornbills (Kemp & Woodcock, 1995). Apart from having the usual distinct features which makes it part of the avian world, hornbills have distinct characteristics of their own. One is the presence of a very large casque sitting atop their long, horn-shaped bills coupled with the unique habit of nest plastering. Nest plastering is when female hornbills use mud, feces, and other similar material to plaster themselves inside their nesting holes as form of protection, leaving only a small gap for provisions.
There are 32 species of hornbills in Asia ranging from India to the Solomon Islands. Most are obligate frugivores (fruit-eaters) but they also eat smaller animals such as insects, crabs, and snakes. Five of the 14 globally threatened species of hornbills in the IUCN Red List are unique to the Philippines, including two species categorized as Critically Endangered (Birdlife International, 2014). An additional 11 species are considered globally as Near Threatened, of which two are Philippine endemics.
The Topic
Dr. JC’s talk was based on his doctoral thesis aimed to set the hornbill records straight once and for all – particularly for the origin of species found in the Philippines. His work translated for Green Speak entitled “Evolution, Ecology, and Ethno-Ornithology as Tools for Conservation” sought to:
- Complete gaps in the available data sets for hornbill DNA (cyt b);
- Come up with a complete molecular phylogeny for the entire family;
- Apply a standard system for delimiting species in Asia;
- Look into population, foraging, and nesting ecology of Philippine species;
- Shed light on human-hornbill relations using ethno-ornithological studies for the first time in the Philippines; and
- Integrate everything to provide a tangible basis for re-setting conservation priorities
Although his work factors in all of earth’s hornbill species, they served to highlight the evolution of species found within the Philippines. For organization, separate findings for evolution, ecology and ethno-ornithology were discussed in sub-categories, followed by a short synthesis to cap it off.
Evolution: Molecular Phylogenetic Analyses of Asian Hornbills to Reveal their Evolutionary History
There are a lot of studies on phylogeny and generally the hornbill family tree. However, there are quite a number of significant gaps to it especially when it comes to Philippine hornbills. Dr. Gonzalez then sought to know 1) where did the hornbills of the Philippines originate from, and 2) how many species do we actually have. The latter question is of great importance when talking about biodiversity conservation because as Dr. Gonzalez puts it “how can you do biodiversity conservation if you do not know how diverse it is?”
To effectively define evolutionary relationships and calculate divergence among hornbills, both mitochondrial and nuclear DNA were used. In addition, an exhaustive examination of museum skins facilitated the comparison of Asian hornbills that were subjected to standard criteria for delimiting species based on differences in morphological measurements, plumage coloration, calls, and other behavioral traits (Tobias et al., 2010) From 6 species listed in the Kennedy guide book and 10 species from the official list of BirdLife International, there are 15 species and subspecies recognized from this study (Gonzalez et al., in prep):
For this part of the study, Dr. Gonzalez looked into two hornbill species namely: Luzon Rufous Hornbill (Buceros hydrocorax) and Luzon Tarictic Hornbill (Penelopides manillae). He looked into the diets and nesting preferences of these two species across different habitat gradients using the Palanan side of Northern Sierra Madre Natural Park as his main site (Gonzalez et al., in prep).
There were three habitat gradients that were examined to determine the influence of forest degradation on frugivore populations. These were as follows (all are 16ha in size):
- Site A – primary site with good forest cover
- Site B – secondary forest selectively logged
- Site C – degraded and currently being logged
As expected, there was a direct correlation between habitat degradation and hornbill population density, so much so that there were even no Luzon Rufous Hornbills found in the degraded forest (Site C). While the Luzon Tarictic population was able to persist, there was still a decline. The same was observed for the population of other endemic fruit-eating forest birds in the area.
As for the hornbill-dispersed fruits, there was not much direct correlation found. While there was lower density observed for larger seeds, which is attributed to the lesser number of hornbills present, but the correlation did not prove to be significant (Gonzalez et al., in prep).
Ethno-Ornithology: Investigating the Ethno-Ornithological Importance of Philippine Hornbills
For this part of the study, Dr. Gonzalez looked into two hornbill species namely: Luzon Rufous Hornbill (Buceros hydrocorax) and Luzon Tarictic Hornbill (Penelopides manillae). He looked into the diets and nesting preferences of these two species across different habitat gradients using the Palanan side of Northern Sierra Madre Natural Park as his main site (Gonzalez et al., in prep).
Ecology: Influence of Habitat Degradation on Population Density of Hornbills and Hornbill-dispersed fruits in the Philippines
There were three habitat gradients that were examined to determine the influence of forest degradation on frugivore populations. These were as follows (all are 16ha in size):
- Site A – primary site with good forest cover
- Site B – secondary forest selectively logged
- Site C – degraded and currently being logged
As expected, there was a direct correlation between habitat degradation and hornbill population density, so much so that there were even no Luzon Rufous Hornbills found in the degraded forest (Site C). While the Luzon Tarictic population was able to persist, there was still a decline. The same was observed for the population of other endemic fruit-eating forest birds in the area.
As for the hornbill-dispersed fruits, there was not much direct correlation found. While there was lower density observed for larger seeds, which is attributed to the lesser number of hornbills present, but the correlation did not prove to be significant (Gonzalez et al., in prep).
Ethno-Ornithology: Investigating the Ethno-Ornithological Importance of Philippine Hornbills
There are several uses of hornbill species across the globe. One such example is the use of Cameroon ground hornbill heads as decoys for hunting in Cameroon, Africa. Another is the use of hornbill jade in China, which are carved from the skulls of Helmeted Hornbills found in Borneo. There are also cultures, which honor the hornbills and possess a strong and deep connection with them as evidenced by rituals, ceremonies, and festivals involving them. However, there has not been much documentation when it comes to its use in the Philippines Gonzalez, 2011).
Hornbills can be found in almost all the islands in our archipelago and these islands also nestle in it very rich cultural diversity. With this, it won’t be a surprise to find several connections with birds as well. In the Philippines in general, hornbill use is mostly for pet trade, followed by food (delicacy), local exhibition, and for trophy/sport. There are tribes, such as the Ifugaos and Illongots who use hornbill heads to adorn the headdress for weddings and as headhunting gear. The population decline observed in Sierra Madre range is even attributed to the former. There are also traditional beliefs such as the one in Palawan. Some groups of indigenous people believed that if a hornbill alights on your roof, it is a sign of bad luck so you should move to a new house. Apparently a rare scenario, since Palawan Hornbills prefer old growth forests and avoid cultivated areas. Deforestation and hunting for food, sport, and the pet trade are main causes for the decline of the Palawan Hornbill (Birdlife International, 2014).
Implications to Conservation
We have 12 endemic hornbill taxa in the country with 5 threatened species, 2 Near Threatened species, and 1 extinct subspecies (Ticao Hornbill). These numbers are alarming especially given the fact that half of the threatened hornbill species in the world are found in the Philippines. While there are efforts to save what we have left, it is proving to be quite a challenge owing to the fact that we are archipelagic, thus entailing a stronger need for manpower and methods to reach far-flung regions.
One of the most important implications of the results of Dr. Gonzalez’s research on Philippine Hornbills has to do with proposed changes in conservation status. Re-evaluation of conservation status is based on new information fitted to standard criteria of IUCN-Birdlife International such as current population estimates and limited distribution (area of occupancy). Now that we have splits, the species considered as threatened and near threatened are actually in a more dire status than we know. Another point of contention is that despite the common knowledge held about habitat degradation and habitat loss, oftentimes it takes hard scientific evidence to get the people moving. Now, we have strong evidence, which will translate to better protection and conservation.
Finally, we need to recognize the links these birds have to different cultures so that we can have better awareness campaigns. It is only as of late that interest in ethno-ornithological studies have picked up and so we are now getting a better understanding of the relationships different cultures have on the birds, and all the perspectives it brings to light. Research methods are continuously evolving and one important technique we should recognize in Dr. Gonzalez’s work is the integration of different fields and tools to achieve a conservation outcome. Dr. Gonzalez is a zoologist and yet in his study, he used field techniques and perspectives of molecular biologists and anthropologists as well. One reason Dr. Gonzalez gave this talk was to show how different fields/techniques can be used and how a collaboration between different researchers can give a much fuller picture of what is at hand and what we could/should do.
Most of the plant and animal species we have in the Philippines are understudied. Researches like these certainly provide us with better tools for understanding the threats at hand and what we could do to face them. So thank you, Dr. JC Gonzalez, for sharing this with us! Conservationists’ hearts all over the Philippines (and possibly, the world) are surely leaping with joy for having an added weapon against species decline!
Watch the presentation on video:
Evolution, Ecology and Ethno-Ornithology as Tools for Conservation: A Study of Hornbills By Dr. Juan Carlos T. Gonzalez
Institute of Biological Sciences and UPLB Museum of Natural History, University of the Philippines Los Baños
March 5, 2014 2-5pm, Coffee Blends, LB, Laguna
video by Jason Apolonio
Pingback:April 2014 | e-BON