limestone karst formations: impt. to ecology, evolution (..)

Limestone Karst FormationsImportance to Ecology, Evolution,

and Conservation of Philippine Amphibians and Reptiles

Arvin C. DiesmosScientist

National Museum of the Philippines(arvin.diesmos@gmail.com)

Salamat Kaayo!

! Philippine Speleological Society! Speleo Davao! DENR! Protected Areas and Wildlife Bureau! Colleagues from the National Museum of the

Philippines, Fauna & Flora International, Wildlife Conservation Society of the Philippines

! Prof. Angel Alcala

Table of ContentsOutline

• Limestone karst-obligate species

• Ecology and evolution

• Gaps in knowledge

• History of exploration in limestone karst habitats

• Conservation implications

DISCOVERING DIVERSITY

Giants of Philippine Herpetology

Angel Chua AlcalaPhoto courtesy of California Academy Sciences Archives.

Giants of Philippine Herpetology

Walter C. BrownPhoto courtesy of California Academy Sciences Archives.

Negros Limestone Frog Platymantis spelaeus, discovered in the 70ʼs Basay, April 2005. Photo by ACD.

Limestone Karst Herpetofauna

Romblon Limestone Forest Gecko Gekko romblonBiak-Na-Bato National Park, Luzon Island. March 2010. Photo by ACD.

Limestone Karst Herpetofauna

Southern Luzon Limestone Frog Platymantis biakBiak-Na-Bato National Park, Luzon Island. January 2009. Photo by ACD.

Limestone Karst Herpetofauna

Southern Luzon Limestone Forest Gecko Gekko carusadensisBiak-Na-Bato National Park, Luzon Island. March 2010. Photo by ACD.

Limestone Karst Herpetofauna

Limestone Karst Herpetofauna

Amphibians (frogs)

Reptiles (lizards)

5 species

5 species

Described Species

Year Locality

Platymantis insulatus 1970 Gigante Island (Panay)Platymantis spelaeus 1982 Basay (Negros)Platymantis paengi 2007 Pandan (Panay)Platymantis bayani 2009 Taft (Samar)Platymantis biak 2010 Biak Na Bato (Luzon)

Limestone Karst Frogs

Year Locality

Gekko cf. mindorensis 1919 Pocanil Point (Mindoro)Gekko gigante 1978 Gigante Island (Panay)Gekko romblon 1978 Mt Progreso (Romblon)Gekko ernstkelleri 2006 Pandan (Panay)Gekko carusadensis 2010 Biak Na Bato (Luzon)

Limestone Karst Lizards

A new species of limestone forest frog (Surigao Province)(Diesmos, A.C., C.A. Ross, R.M. Brown, in review)

New Discoveries

Limestone Karst Herpetofauna

Amphibians (frogs)

Reptiles (lizards & snakes)

10–20 more new species

15–30 more new species

Undescribed Species

ECOLOGY & EVOLUTION

Brown & Alcala 1982; Alcala et al. 1998; Siler et al. 2010.

! Only in limestone karst habitat

Natural History

! Obligate to limestone karst forest and caves

Limestone Karst HabitatSiargao Island. August 2010. Photo by ACD.

Day & Urich 2000; Restificar et al. 2006.

Limestone karst distribution in the Philippines (10% of land area)

! Frogs use caves as breeding sites (breeding and egg deposition)

Natural History

! Frogs and lizards inhabit limestone karst forest as primary refugia

Brown & Alcala 1982; Alcala et al. 1998; Siler et al. 2010.

Eggs are deposited in crevices of cave walls and boulders.Bulacan Province, Luzon Island. January 2009. Photo by ACD.

Eggs develop directly into frogs; males perform parental care.Photo by ACD.

Mahilig sa mga singit.

! Site-endemic species (narrow-endemics)

Geographic Distribution

Brown & Alcala 1982; Alcala et al. 1998; Siler et al. 2010; Diesmos & Brown 2011.

Brown & Diesmos 2009, Siler et al. 2010; Diesmos & Brown, 2011

Frogs

Lizards

! Site-endemic species (narrow-endemics)

! Geographic distribution of co-evolved species do not overlap

Brown & Alcala 1982; Alcala et al. 1998; Siler et al. 2010; Diesmos & Brown 2011.

Geographic Distribution

Platymantis biak

Platymantis (Surigao)

Platymantis biak

Platymantis (Siargao)

Bioacoustics

DNA Sequence Data

Complex geological history and long periods of isolation.

Pleistocene Islands

Borneo

Luzon

Palawan

Mindanao

Ngano man?

! Biodiversity is generally distributed according to paleo-islands: Pleistocene Aggregate Island Complex (PAIC)

Brown & Diesmos 2002; Brown & Guttman 2002; Evans et al. 2003; Esselstyn et al. 2008; Brown & Diesmos, 2009.

Biogeography

Centers of biodiversity & endemism

12

3

45

6

78

9Inger 1954; Heaney 1985; Ong et al. 2002; Brown & Diesmos 2002, 2009.

Inger 1954; Heaney 1985; Brown & Diesmos 2002, 2009.

GAPS IN KNOWLEDGE

! Numerous karst habitats are unexplored! Biological field surveys

Priority Research

! Basic information on natural history is lacking! Natural history studies

! Conservation status of species need to be assessed! Ecological information required

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No data frogs

No data reptiles

New species

!?

Many karst areas are unexplored biologically.

Natural history collections are invaluable resource for biodiversity studies.

CONSERVATION

Intensive and extensive kaingin farming.Image by AC Diesmos, San Mariano, Isabela Province, Luzon, 2006.

Destructive mining is the greatest threat to remaining forests.

Image from flickr.com/photos/storm-crypt/.

Diesmos et al. 2002; image by AC Diesmos, Mt. Mayon, Albay Province, Luzon, 2004.

Species ASpecies BSpecies C

Species DSpecies E

Species F

Loss of lowland forest affects low elevation species

Source: IUCN, 2011

Most of our species are found in the lowlands.

IUCN Locality a Protected Area?

Platymantis insulatus Critically End Gigante Island (Panay); Not PAPlatymantis spelaeus Endangered Basay (Negros); Not PAPlatymantis paengi Not Assessed Pandan (Panay); PAPlatymantis bayani Not Assessed Taft (Samar); PAPlatymantis biak Not Assessed Biak Na Bato (Luzon); PA

Limestone karst species are in big trouble.

IUCN Locality a Protected Area?

Gekko cf. mindorensis Pocanil Point (Mindoro); Not PAGekko gigante Vulnerable Gigante Island (Panay); Not PAGekko romblon Mt Progreso (Romblon); Not PAGekko ernstkelleri Vulnerable Pandan (Panay); PAGekko carusadensis Biak Na Bato (Luzon); PA

Limestone karst species are in big trouble.

Much of Biak Na Bato National Park is degraded and remnant forest habitat. From Google Earth.

...and so is Basay (locality of Negros Limestone Forest Frog).From Google Earth.

Pounds & Crump 1994; Pounds et al. 1999; Alexander & Eischeid 2001; Blaustein et al. 2001; Gibbs & Breisch 2001; Alcala et al. 2002; Corn 2005; Araujo et al. 2006; Whitifield et al. 2007; Stuart et al. 2008; Wanger et al. 2009.

! Changes in distribution and population

Climate Change Impacts

Stratified distribution pattern in elevation

Diesmos et al. 2002; image by AC Diesmos, Mt. Mayon, Albay Province, Luzon, 2004.

Species ASpecies BSpecies C

Species DSpecies E

Species F

Climate warming will affect elevational distributions

Diesmos et al. 2002; image by AC Diesmos, Mt. Mayon, Albay Province, Luzon, 2004.

Species A

Species B

Species C

A Bit of Good News.

Tourism has greater potential to generate more revenues.Diesmos, Mallari & Altamirano, unpublished.

Key Biodiversity Areas = Key Adventure Areas

! Limestone karst forest habitats are sub-centers of diversity and endemism

Synopsis

! Generally unexplored biologically

! Cave Act (R.A. 9072) may need to be expanded to include important karst areas not within protected areas system

! Highly threatened unique and specialized habitats and species

! Management plans must include management of species