More than 700 species of birds have been recorded in the Philippines. That’s quite a lot. Even more astounding is the number of those that are endemic to this country; 241 at last count. 34% endemicity for birds is very high, and the country ranks 3rd worldwide in this statistic.
I was asked to give a presentation about these and other facts at the GreenWild Expo that was held at the SMX center of SM Aura in BGC in November 2019. A one-hour presentation with the topic; An introduction to the birds of the Philippines. As it happens I’m quite fond of birds of the Philippines and know a bit more about then than the average person. I also like talking about them. So no problems there. I give a similar presentation during our Bird and Breakfast tours at the Masungi Georeserve, so I had a starting point. However there is so much to tell that one hour is way to short to do it exhaustively. Therefore hereby part 1 of a series of blogs about the birds of the Philippines.
How many species of birds are there in the Philippines?
This is a question often asked by people when I give a guided trip. I am always enthusiastic about the birds and all the gorgeous endemics we have, that I sometimes forget that many people are not aware of the staggering numbers. Seven hundred bird species have been recorded in the country. Well, more or less…
Actually by the time I write this, a few more have been recorded already. I am a member of the WBCP records committee, and will therefore be basing myself on the Annual Checklist of Birds in the Philippines (see reference below). In this case that is the list of 2019. However that is the list produced in January 2019, and by now, December, it is already outdated again. A new checklist will be published by us in January 2020, and will be available via birdwatch.ph
In the Checklist of the Birds of the Philippines 2019, you can find all 700 species listed and ordered by family.
Are there different authorities for bird taxonomy?
You see, the number of birds in a country is not a static number. We are not even talking about the actual number of species currently occuring in the Philippines, which is impossible to accurately determine due to migration. It has more to do with taxonomy as well as new country records. Let’s start with the taxonomy and get it out of the way. There are three main authorities when it comes to bird taxonomy worldwide. International Ornithologists' Union, formerly known as the International Ornithological Committee is still known best by its earlier acronym IOC, and thus IOC list which will be retained throughout the text. The WBCP annual checklist is based on the IOC list (with a few exceptions which I will not go into today). IOC consists of a group of around 200 international ornithologists who discuss things, mainly to do with bird taxonomy. The second is a publication by the Cornell Lab of Ornithology, which has been providing annual updates to the Clements Checklist of Birds of the World. This list is more commonly known as the Clements list. Clements is used by the American Birding Association, as well as the online database from Cornell; eBird. To then further complicate things there is the Handbook of the Birds of the World (HBW), a multi-volume series produced by the Spanish publishing house Lynx Edicions in partnership with BirdLife International. These main three authorities do not always agree on the number of bird species in the world due to the simple fact that it is not black-and-white. After all, a species does not pop into existence but slowly evolves through millenia of natural selection, but at what point do we call it a separate species from a similar but not quite subspecies (we call this a ‘split’ or ‘splitting’)? Therefore, when research by one authority points out the differences between subspecies are large enough to split them, or the other way around, do not prove to be large enough after all and should be lumped together again (called ‘lumping’), the other authorities will look at the evidence and argue about it amongst themselves before generally reaching a consensus in the end. This could take a while, and in the period between, there are subspecies that some consider separate, and others say are still one species. A good example of this in the Philippines is the Rufous Hornbill (Buceros hydrocorax by IOC), which according to Clements has to be split into the Northern Rufous Hornbill (Buceros hydrocorax) and the Southern Rufous Hornbill (Hydrocorax mindanensis). Eventually they will work it out, for the meantime, we have a different number of species from the Philippines according to which list you follow. To be clear, in this text I will be following the IOC list, as this is the authority that the Wild Bird Club of the Philippines uses, and therefore the list used to create the Annual Checklist of Birds of the Philippines 2019 (and other years).
In the Checklist of the Birds of the Philippines 2019, on the second tab ‘Sortable Species List’, you can find columns S, T and U for the names on the lists of IOC, HBW and Clements respectively (where different from the WBCP checklist).
What is the difference between extinct and extirpated?
This means the list could shrink or grow every year even if no other work is done. Practically, of course, it means very little to us. More important is the actual number of birds living or migrating through the country. Basically, the way the list works, is that once you are on it, only taxonomic changes can take you off it again (when lumping). In reality, of course, species can go extinct and for all practical purposes disappear from the list. There again, there are complications. In the Philippines, the Cebu Flowerpecker (Dicaeum quadricolor) was thought to have gone extinct early in the 20th century after not being seen for decades, before all of a sudden it popped up again in several small forest patches in 1992. I’ve tried looking for it myself on several occasions, however never found it. It has again been several years since the last confirmed sighting, so there is a fear that it has gone extinct ‘again’. However it has not yet officially been declared extinct, rightly so seeing as to how difficult it is to be certain. A species of which it is more certain is the Spot-billed Pelican (Pelecanus philippensis) in the Philippines. Previously occuring in sizeable flocks in Laguna De Bay near Manila among other places, it was hunted until there were no more. Technically, and luckily, it is not extinct, as there are still populations of this species in other countries. The term, then, is extirpated; it no longer occurs in a specific locality, in this case the Philippines. This is also known as ‘locally extinct’. The Sarus Crane (Antigone antigone) is another example of a similar situation; it was last recorded in 1910 and now believed to be extirpated. As they were never recorded, in the Philippines, on any other island than Luzon, this is likely true. The same cannot be said however for some other species, for example the Wooly-necked Stork (Ciconia episcopus), which has similarly not been seen since the early 20th century, however was recorded back then from a number of locations such as Basilan and Mindanao, where current day surveying is very difficult due to politcal instability. Thus, it is possible they still occur in these places. On the WBCP list, than, the stork is listed as ‘may have become extirpated from Luzon’. Just to show, the Oriental Darter (Anhinga melanogaster), which had similarly not been seen for many years, was spotted in one of the few trips made to Liguasan Marsh, Maguindanao when the opportunity presented itself to a few birdwatchers last March. It is not always a matter of rediscovering a species that was always there. The Masked Booby (Sula dactylatra) is the third species on the WBCP list that is listed under EX (extirpated) besides the pelican and the crane. However, there is ample proof of an individual on Tubbataha! It was last recorded as a breeding species there in 1995, and then not seen again for many years and declared locally extinct. However, in May 2016 a single male individual was seen again on the bird/north islet of the Natural Park, and has been recorded often since. Unfortunately, a single individual of course does not make a species, and certainly not a viable population, therefore the listing as extirpated stands. Promising news though, a second individual was spotted just last October 2019. It is unsure whether this second individual is a female, and even then breeding is not guaranteed, but it is certainly a good sign.
In the Checklist of the Birds of the Philippines 2019, on the main tab ‘Birdlist’, you can filter column J ‘PH Status’ to reflect Extirpated bird species (EX). Do not confuse this with ‘E’ for Endemic (see further below)
Are there endemic birds that have not been seen for a long time but are not extinct?
The above examples, including all three species actually declared extirpated in the Philippines (Sarus Crane Antigone antigone, Spot-billed Pelican Pelicanus philippensis and Masked Booby Sula dactylatra) all still have populations abroad, and are therefore not yet extinct as a species. There are a number of other cases however, such as the briefly mentioned Cebu Flowerpecker (Dicaeum quadricolor) which are endemic to the Philippines, meaning they do not occur anywhere else in the world (see further below for more information). Thus, if they are extirpated from the Philippines, they do go extinct as a species. As it is very difficult to prove a species truly no longer exists, and have been known to turn up decades later, the process of declaring a species extinct is a tricky one. Not only should the species not have been recorded for a long period of time, say 50 years or so, but also should people have gone looking for it specifically and not found it, before we can say that it is truly gone. Two species merit mentioning here specifically. The Negros Fruit Dove (Ptilinopus arcanus) is known only from one single specimen collected on Mt. Kanlaon in 1953. Despite surveys to the species, it might still persist in the mountainous areas of Negros Island. The Sulu Bleeding-heart Pigeon (Gallicolumbus menagei) is even older. The first, and only, record is from two birds collected in 1894. There have never been confirmed reports after that time. Political instability in the area have made surveys almost impossible in the past, so there is still a chance that it survives in the remote island of Tawi-Tawi.
In the Checklist of the Birds of the Philippines 2019, these are not specifically indicated. However you can find a lot of the above information on the main tab ‘Birdlist’ and in the column N ‘Note’
How many migratory birds do we have in the Philippines?
A large number of birds on the official Checklist of Philippine Birds consists of migrants; those birds that travel from the far away to warmer regions when it gets colder in the far north. However even here there is some uncertainty, or at least confusion. The actual number varies between 107 up to 263, depending on what you understand as a migratory species. Let me break it down for you. There are 107 known migratory bird species that travel to or through the Philippines each year around October, and leave again around March. However, there are also 20 species that do the same, but besides the migratory population, some of the individual birds do not leave but reside here permanently. So part of the species’ population migrates, another part does not. Then there are 7 species of which we suspect the same, but we’re not really certain. This means that these are generally migratory birds, of which we have unverified claims that there are some resident populations, or there are resident species, some individuals of which may migrate. The largest group however, 129 species, consists of species that have only been recorded in the Philippines a handful of times. These are generally migratory birds that usually do not fly to the Philippines, but may have been blown off course in strong weather. Some species are very rare in any case, so any sighting would be easy to miss. Or it may be that they do migrate to the Philippines, though rarely, and we simply do not know of it due to a small number of bird watchers in the country. These are called Accidentals, or Vagrants. Only when we have recorded a species on more than 20 separate occasions to we consider it a (rare) migrant instead.
In the Checklist of the Birds of the Philippines 2019, on the main tab ‘Birdlist’, you can filter column J ‘PH Status’ to reflect Resident (R), Migrant (M), Accidental (A), Resident and Migrant (R, M) and those confusing ones via (R, M?) and/or (M, R?)
What is the difference between resident and endemic?
Last, but certainly not least, there are the resident species. Again, due to some uncertainty with a few species that might or might be residents as well as migrants, the exact number is not written in stone. Also again, this group is most susceptible to splits as resident populations as a rule have the least interaction with populations on other islands or other geographic locations. But we can say there are at least 421 species in the Philippines which live here year round and breed here. The most exciting group within these, at least to birdwatchers, are the endemic species. Endemic means ‘restricted to a specific area’. In general we then speak of a country, in this case the Philippines, and call these country endemics, Philippines endemics, or simply endemics. However, some species are more restricted than others, and are for example restricted/endemic to Luzon Island (for example the Montane Racket-tail Prioniturus montanus), or to the West Visayas (think of the Visayan Hornbill Penelopides panini)
In the Checklist of the Birds of the Philippines 2019, on the main tab ‘Birdlist’, you can filter column J ‘PH Status’ to reflect Resident (R), Endemic (E) and Near Endemic (NE). You can further narrow down endemicity level on the second tab ‘Sortable Species List’ via column J ‘Endemicity’
You may download the WBCP checklist for personal or scientific reference use only. The Wild Bird Club of the Philippines retains the copyright for the list and it should not be used for commercial purposes without prior written permission from WBCP. If any of this material is used or included in any other publication or private report, please acknowledge the WBCP using the following citation: Jensen, A., D. Allen, R. Hutchinson, C. Perez, W. van de Ven & JJ. Brinkman (2019): Checklist of birds of the Philippines. Wild Bird Club of the Philippines. www.birdwatch.ph