Photographic Guide to the Birds of Southeast Asia. Morten Strange
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birdwatching in the forest is as tough as it gets. In rainforest, the trees grow to a height of 30 metres or more, and the foliage is massive. Less than two percent of the outside light reaches the forest floor and the humidity stays near 100 percent, even in the afternoon. But then, forest birdwatching is also the most rewarding. You can walk the same forest trail twenty times, week after week, and then the twenty-first time you might see a species you have never seen before in your life, such is the diversity and the scarcity of forest residents.
Conditions are challenging, even in the somewhat lower deciduous forests further north. In addition to the poor viewing conditions the birds are shy and take off at the least disturbance. In general it is better to visit during the dry season, from December to February, and go where the forest is less dense and where many migratory warblers, thrushes and flycatchers augment the resident bird fauna.
Pheasants, hornbills, broadbills, woodpeckers, leafbirds, babblers and flowerpeckers are almost exclusively forest bird families; night-birds, bulbuls, drongos, cuckoo-shrikes and flycatchers are also well represented.
As you proceed higher, the avifauna changes. At 900 metres you enter the montane forest where you will discover a totally different set of birds. This astonishing transformation is once again a highlight of birdwatching in this region. You can drive for a couple of hours from Kuala Lumpur to Fraser's Hill in Malaysia, or from Chiang Mai to Doi Inthanon in Thailand, and so profound is the change that you might well have crossed the ocean to another faunal region. You will then have to begin familiarising yourself with 50 or 60 new species that you simply will never find in the lowlands.
Insect life is abundant at montane elevations and insectivorous bird families such as babblers, warblers and flycatchers are especially well represented, but almost all the other forest bird families such as pigeons, bulbuls, broadbills, cuckoo-shrikes, thrushes, fantails, sunbirds and flowerpeckers have one or a few representatives in the mountains.
The higher reaches of the upper montane habitat, above 2,400 metres, and the alpine habitat near and above the tree limit are not of that much interest in this region, simply because there is little of it. It only exists in the Himalayan foothills of Myanmar and Yunnan (south China), which are not very accessible to tourists, and in Sabah within the Kinabalu National Park. At Kinabalu the subcamp at 3,400 metres is where the alpine habitat starts and this is really as far as birders need to go. Pushing all the way to the summit at 4,101 metres may bring you a nice view and a bout of altitude sickness, but no significant bird sightings apart from the occasional White-bellied Swiftlet, which is better observed at sea level.
The bird year
The region covered by this book is above the Equator and is part of the northern hemisphere. Close to the Equator, from peninsular Thailand and the so-called Tenasserim part of Myanmar and south, tropical conditions prevail, with heavy rainfall all year round, and insignificant changes in the seasons. Even then, the breeding of resident birds is not evenly spread throughout the year. Surveys show that most birds breed at the beginning of the year, from February towards the end of the northeast monsoon season, which dumps more rain than usual over most of the area during the months from November to January. Breeding peaks between April and May, and lasts until June or July, with some birds such as seabirds breeding into August. It is rare to find any nests in the later part of the year.
Actually, it is not easy to find nests in the tropics. Many birds build high in remote forest areas and within dense foliage. But the breeding season is an important time for the birdwatcher, because males tend to mark their territory aggressively, so there are more calls and often the birds are somewhat bolder and easier to observe at this time. Towards the end of the breeding season juveniles appear and add to the activity. Passerines typically feed their young for some time after they fledge, and many breeding records are established by observing the feeding.
Above the 50th parallel, a change to a more seasonal climate occurs. The change is complete above the 20th parallel, where the climate is subtropical with a distinct hot and cold season. Significant local variations prevail, but in general these northern regions experience a cold season with little rainfall lasting from December to February, Over most parts of continental Thailand and Indochina, 80 percent of precipitation falls during the southwest monsoon from May to October, while the cold months are very dry. Breeding in this region is seasonal, with most forest birds breeding in the spring, which is typical for northern hemisphere birds. However, evidence suggests that waterbirds may locally prefer to nest during the end of the wet season, from July into January, but this needs further verification.
Southeast Asia lies towards the end of the East Asia migratory flyway. Migrants from temperate, subarctic and arctic parts of Asia converge on the region during the northern winter. Some pass through during peak migration from September to November and on the return flight from March to April. Many others go no further and make the region their winter quarters.
The actual movement of flying birds is difficult to observe in this region, since most species tend to change location at night, or fly high, out of sight. However, they tend to follow the coastlines, and passage migrants and winter visitors can turn up anywhere depending on habitat requirements. Coastal mudflats (for the water-dependent species) and wooded areas just behind the beach (for arboreal birds) are particularly good places to birdwatch during the winter season.
In conclusion, the beginning of the year is a good time to visit Southeast Asia. At this time the northern subtropical areas experience cool, dry weather and many migrants augment the local avifauna. Towards the end of winter into early spring, the resident birds become more active and conspicuous. In tropical areas, the heavy rainfalls of December subside about this time and the many resident forest birds become more vocal and daring. Alternatively, try to visit from September to November after the subtropical rains, when the northern migrants arrive, but before the tropical monsoons begin. In the subtropics watch for breeding waterbirds.
Places to go
Birds do not recognise political demarcations, so national boundaries are really not very useful when describing the avifauna of a region, however people do, and active birdwatchers keep lists, and tally species they have seen within certain countries. Within the region covered in this volume, some major political entities exist, thus in the following table we list the nations and territories most visited by birdwatchers. Endemics refer to restricted range species found only in that country, except for East Malaysia and Brunei where numbers refer to Borneo endemics.
Just how many birds can one see in total in this region? Obviously many of the species listed under countries will be repeats. For a measurement of the total diversity Robson (2000) lists 1,251 species, King et al (1975) list 62 additional ones for Taiwan, Hainan. MacKinnon & Phillipps list 37 species endemic to Borneo, and Dickinson et al. (1991) has 169 endemics for the Philippines. Calculated this way about 1,519 different birds are found in Southeast Asia. But if you see the 668 covered in this volume, you will have done well.
Conservation
Many of the birds in this book are adaptable and prolific. The Yellow-bellied Prinia readily invades forest areas cleared for development; and the Common Myna visits gardens and even invades people's homes to grab food. These birds have no problem surviving, but others adapt poorly to changes in their environment, so if their forest is removed or their island built over, they have no place to go. They need our help if they are to survive.
'Conservation begins with enjoyment' says the English comedian and professional birdwatcher Bill Oddie. In the 1994 BirdLife International study, published in Collar et al. (1994), it was documented that no less than 1,111 bird species comprising 11 percent of the world's avifauna could be regarded as globally threatened with extinction. A further 875 (or nine percent) was near-threatened. In other words, one out of five of all birds in the world is doing poorly or about to disappear.
Even in this book, which mainly features the easy-to-see species, 29 birds are globally threatened, a further 31 birds fall into the near-threatened category, which totals nine percent of the species covered.
The BirdLife study also revealed that most of the threatened birds live in the tropics, in countries with relatively low national incomes. They are forest birds (65 percent) and the main causes for their decline are habitat