| Citation |
IUCN SSC Amphibian Specialist Group 2018. Alcalus mariae. The IUCN Red List of Threatened Species 2018: e.T41226A114911328. http://dx.doi.org/10.2305/IUCN.UK.2018-1.RLTS.T41226A114911328.en. Downloaded on 14 May 2019. |
Description |
Geographic Range
NATIVE
Extant (resident)
Philippines
NUMBER OF LOCATIONS
1
UPPER ELEVATION LIMIT
900 metres
LOWER ELEVATION LIMIT
500 metres
UPPER DEPTH LIMIT
LOWER DEPTH LIMIT
Geographic Range in detail
ESTIMATED AREA OF OCCUPANCY (AOO) (KM²)
CONTINUING DECLINE IN AREA OF OCCUPANCY (AOO)
EXTREME FLUCTUATIONS IN AREA OF OCCUPANCY (AOO)
ESTIMATED EXTENT OF OCCURRENCE (EOO) (KM²)
788.39
CONTINUING DECLINE IN EXTENT OF OCCURRENCE (EOO)
EXTREME FLUCTUATIONS IN EXTENT OF OCCURRENCE (EOO)
CONTINUING DECLINE IN NUMBER OF LOCATIONS
EXTREME FLUCTUATIONS IN THE NUMBER OF LOCATIONS
RANGE DESCRIPTION
This species is currently known only from Mount Balabag, in the Mantalingajan mountain range, on the island of Palawan in the western Philippines, between 500–900 m asl. It might range more widely. It is known from one threat-defined location and its extent of occurrence (EOO) is 788 km2.
Population
CURRENT POPULATION TREND
Decreasing
NUMBER OF MATURE INDIVIDUALS
POPULATION SEVERELY FRAGMENTED
No
CONTINUING DECLINE OF MATURE INDIVIDUALS
Population in detail
EXTREME FLUCTUATIONS
NO. OF SUBPOPULATIONS
CONTINUING DECLINE IN SUBPOPULATIONS
EXTREME FLUCTUATIONS IN SUBPOPULATIONS
ALL INDIVIDUALS IN ONE SUBPOPULATION
NO. OF INDIVIDUALS IN LARGEST SUBPOPULATION
DESCRIPTION
Surveys in 2001 and 2007 found the species to be common to abundant at elevations between 500–900 m asl (R. Brown pers. comm. 2007, Philippines Red List Assessment Workshop May 2017). Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.
Habitat and Ecology
SYSTEM
Terrestrial, Freshwater (=Inland waters)
HABITAT TYPE
Wetlands (inland), Forest
GENERATION LENGTH (YEARS)
CONGREGATORY
MOVEMENT PATTERNS
Not a Migrant
CONTINUING DECLINE IN AREA, EXTENT AND/OR QUALITY OF HABITAT
Yes
Habitat and Ecology in detail
HABITAT AND ECOLOGY
This semi-aquatic species occurs in sub-montane and montane forest along streams and rivers along which it has been observed perching on rocks and boulders. It probably breeds on land by direct development, like other members of its genus (Philippines Red List Assessment Workshop May 2017).
CLASSIFICATION SCHEME
Habitats Suitability Major importance
1. Forest 1.6. Forest - Subtropical/Tropical Moist Lowland Suitable Yes
5. Wetlands (inland) 5.1. Wetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls) Suitable Yes
Threats
Residential & commercial development
Housing & urban areas
Agriculture & aquaculture
Annual & perennial non-timber crops
Energy production & mining
Mining & quarrying
Biological resource use
Logging & wood harvesting
Threats in detail
THREATS
The major threat is the destruction and conversion of both lowland and montane rainforest habitat on Palawan due to small-scale agricultural activities, large-scale oil palm plantations, wood collection for charcoal production, and expanding human settlements due to high levels of immigration (Philippines Red List Assessment Workshop May 2017). There are applications for mining the nickel, chromite, and gold in the region, but no mining activities are currently permitted within the range (Philippines Red List Assessment Workshop May 2017).
CLASSIFICATION SCHEME
Threats Timing Stresses Scope Severity Impact score Invasive species Virus
1. Residential & commercial development 1.1. Housing & urban areas Ongoing
1. Ecosystem stresses 1.1. Ecosystem conversion
1.2. Ecosystem degradation
Low Impact: 3
2. Agriculture & aquaculture 2.1. Annual & perennial non-timber crops 2.1.2. Small-holder farming Ongoing
1. Ecosystem stresses 1.1. Ecosystem conversion
1.2. Ecosystem degradation
Low Impact: 3
2.1.3. Agro-industry farming Ongoing
1. Ecosystem stresses 1.1. Ecosystem conversion
1.2. Ecosystem degradation
Low Impact: 3
3. Energy production & mining 3.2. Mining & quarrying Future
1. Ecosystem stresses 1.1. Ecosystem conversion
1.2. Ecosystem degradation
No/Negligible Impact: 1
5. Biological resource use 5.3. Logging & wood harvesting 5.3.1. Intentional use: (subsistence/small scale) [harvest] Ongoing
1. Ecosystem stresses 1.2. Ecosystem degradation |
