Global InformationTadlac Lake information
| Tadlac Lake | |
|---|---|
| Crocodile Lake | |
 The lake as seen from the eastern shore in 2013 | |
  Tadlac Lake Location within the Philippines | |
| Location | Brgy. Tadlac, Los Baños, Laguna |
| Coordinates | 14°10′57″N 121°12′23″E / 14.18250°N 121.20639°E |
| Type | Volcanic maar |
| Primary inflows | none |
| Primary outflows | none |
| Basin countries | Philippines |
| Managing agency | Laguna Lake Development Authority |
| Max. length | 650 meters (2,130 ft)[1] |
| Max. width | 503 meters (1,650 ft)[1] |
| Surface area | 22.7 hectares (56 acres)[2] |
| Average depth | 27 meters (89 ft)[3] |
| Shore length1 | 1.8 kilometers (1.1 mi)[2] |
| Surface elevation | 2 meters (6 ft 7 in) |
| Islands | none |
| Settlements |
|
 | |
| 1 Shore length is not a well-defined measure. | |
Tadlac Lake, also colloquially known as Crocodile Lake, is a freshwater volcanic maar lake located in Barangay Tadlac, in the municipality of Los Baños, Laguna. The lake-filled maar is located along the southern shore of Laguna de Bay, the largest lake in the country, with Crocodile Lake protruding out of the shore of the larger lake. If not for its slightly-elevated crater rim, Crocodile Lake would be wholly engulfed by Laguna de Bay.[4]
The volcanic lake is one of the maars of the Laguna Volcanic Field. It is listed as one of the inactive volcanos in the Philippines by the Philippine Institute of Volcanology and Seismology (PHIVOLCS).[5]
Tadlac lake is also notable for its history of annual Lake overturns, locally called langal. This phenomenon, rare elsewhere but usually occurring in Tadlac lake during the cold months of December to February, is the result of trapped carbon dioxide (CO2) erupting from the deep layers of the lake towards the surface, leading to fish kills due to low levels of dissolved oxygen.[3]: 6 This phenomenon was greatly heightened by the introduction of aquaculture to the lake in the mid-1980s, eventually leading to a massive and costly fishkill in 1999, which in turn led to the cessation of aquaculture activities on the lake.[3]: 6
Prior to the introduction of aquaculture, Crocodile Lake was considered as an oligotrophic lake, having low nutrient content and low algal production, resulting in very clear water with high drinking-water quality.
Commonly confused or misnamed as Alligator lake. Alligators are only present in the Everglades in the United States and China's Yangtze River. Never present in the Philippines. Crocodiles however have been known to inhabit Laguna lake and surrounding bodies of water until the early to mid 1900s.
- ^ a b Measured using Google Earth.
- ^ a b gard777us (2011-12-12). "Crocodile Lake area". Google Earth. Retrieved on 2013-12-30.
- ^ a b c Santos-Borja, Adelina C. (2008). "Multi-Stakeholders’ Efforts for the Sustainable Management of Tadlac Lake, The Philippines". Research Center for Sustainability and Environment, Shiga University.
- ^ "Crocodile Lake, Los Baños, Calabarzon, Philippines". Google Maps. Retrieved on 2013-12-31.
- ^ "Inactive volcanoes of the Philippines". Philippine Institute of Volcanology and Seismology. Retrieved on 2013-12-31.