Human-Altered Tree-Based Habitats and Their Value in Conserving Bird and Bat Diversity in Northeast Luzon, The Philippines - Smallholder Tree Growing for Rural Development and Environmental Services - page 334

to the Philippines, led to the identification of the entire Philippines as a biodiversity
conservation hotspot in a global comparison of conservation priorities (Myers et al.
2000).
Since the early 1970s, the Philippine government has been promoting reforesta-
tion through a variety of forestry support programs. Most of the current programs
provide tenure rights of government-owned land earmarked for reforestation to
smallholders and communities. Assistance in reforestation is often provided by
local government, NGOs and international donors (Harrison et al. 2004). Officially,
25,000 km 2 is covered by such forest management programs but not all lands have
been reforested (Harrison et al. 2004). The FAO (2007) reports a total area of
6,200 km 2 forest plantations in the Philippines. A number of social, economic and
physical factors have hampered successful reforestation on a larger scale (Pasicolan
et al. 1997). Reforestation efforts in the Philippines usually concentrate on a few
tree species, sometimes planted in mixtures of two up to five species but mainly
established in the form of mono-cultures of fast-growing exotic species, such as
Gmelina arborea (Lasco and Pulhin 2000). Gmelina arborea is a fast-growing
deciduous tree native to tropical moist forests of mainland Asia. This species is
widely introduced in South America, Africa and Asia. It can tolerate a 6-7-month
dry season and occurs up to 1,500 m a.s.l. The timber is reasonably strong for its
weight and in the Philippines particularly used for construction and furniture
(Center for New Crops & Plant Protection 2007). A possible synergy between
reforestation, carbon emission offsets and biodiversity conservation has been iden-
tified as an opportunity resulting from global climate change mitigation strategies.
There is concern however that exotic tree plantations contribute little to biodiversity
conservation as opposed to reforestation efforts using mixed native species (Stier
and Siebert 2002).

16.1.2 Extinction or Persistence of Forest Species

in Human-Altered Landscapes in the Philippines?

Brooks et al. (2002) warn that 58% of Philippine endemic forest species might go
extinct as a result of deforestation. This extinction prediction is based on species-
area relations and assumes that endemic forest species will not be able to adapt to
or persist in any landscape other than undisturbed old growth forest. However, not
a single endemic mammal or bird species has been reported truly extinct in the wild
in the Philippines. Three different explanations can be put forward: (1) species have
gone extinct unnoticed, (2) there is a time gap between habitat loss and species
extinction (Brooks et al. 1999) or (3) endemic forest species are less vulnerable to
deforestation and forest disturbance than assumed.
It is unlikely that large-scale extinctions of better studied taxa such as birds have
occurred unnoticed in the Philippines, as birds have been described relatively well
and monitored since the start of the 20th century, i.e., the onset of large-scale defor-
estation (e.g. Dickinson et al. 1991 for an overview of literature on Philippine birds).