Species
Trey riel
Small carps of the Tonle Sap and the Mekong, caught in great numbers as the floods fall and used to make prahok.
Trey riel is the Khmer name for a group of small carps of the Tonle Sap and the Mekong, the fish traditionally used to make prahok. The name means "fish money".[1][2] The BBC writes that the Cambodian currency, the riel, is named after the fish.[2]
Species
The name covers several fish of the carp family, 10 to 17 cm long, among them Henicorhynchus siamensis, Henicorhynchus cryptopogon and Thynnichthys thynnoides.[1] A review of the Tonle Sap fisheries published by the Food and Agriculture Organization of the United Nations notes that "trey riel" in Cambodia's catch statistics takes in three, possibly five, species of Henicorhynchus.[3] Nicolaas van Zalinge, of the Mekong River Commission's fisheries program, gives Henicorhynchus siamensis as the trey riel and writes that it first spawns at about one year old.[4]
Life cycle and migration
Trey riel are among the small, fast-growing fish that breed in the flood season. They move onto the flooded plains in the rains, multiply there and are easily caught when the water goes down in the dry season.[1] The review groups Henicorhynchus siamensis with these quick breeders, which are mostly used for prahok and fish sauce or fed to fish raised in cages.[3]
As the water falls, the fish leave the lake and its floodplain for the Mekong. The dai, large bag nets fixed across the Tonle Sap River, are fished from the end of September until March, and their catch peaks in January. The fish move in regular waves, which are at their highest six to three days before the full moon.[3] A 2024 study of dai catches from 2002 to 2008 looked at a related small mud carp, Henicorhynchus entmema, which it calls a keystone species of the system. It found that the volume and timing of the river's flow mattered most to that fish's migration.[5]
Catch
In the 1995 to 1996 season, trey riel made up 21 percent by weight of the catch of Cambodia's large and medium-scale fisheries, more than any other fish, and 9 percent of its value. In a survey of small-scale fishing cited by the same review, a third of fishing households named trey riel as the most important fish they caught.[3] Van Zalinge wrote that most of the smaller species had not declined and made up most of the catch, since fewer large predators were left to eat them.[4]
In 2009 Cultural Survival Quarterly wrote that trey riel numbers had dropped sharply after record catches in 2006 and 2007, which it put down to warmer water, and that the price of prahok had more than tripled.[6]
Food
Prahok, the fermented fish paste at the heart of Khmer cooking, is traditionally made from trey riel.[2] The authors of the Journal of Ethnic Foods study read the name "fish money" as a sign of how prahok turns fish with little value of their own into a food that people prize.[1] The chef Ros Rotanak, known as Chef Nak, told the BBC that the monsoon is the only time of year with so many fish, so they have to be preserved for the months that follow.[2]
References
- ↑ 1.0 1.1 1.2 1.3 Journal of Ethnic Foods, Karen LeGrand, Buntong Borarin and Glenn M. Young, Tradition and Fermentation Science of prohok, an ethnic fermented fish product of Cambodia (May 6, 2020)
- ↑ 2.0 2.1 2.2 2.3 BBC Travel, Marissa Carruthers, Prahok: The pungent fish elevating Cambodian cuisine (July 8, 2021)
- ↑ 3.0 3.1 3.2 3.3 Food and Agriculture Organization of the United Nations, Part II. Tonle Sap Fisheries (undated)
- ↑ 4.0 4.1 Food and Agriculture Organization of the United Nations, Nicolaas van Zalinge, Data Requirements for Fisheries Management in the Tonle Sap (undated)
- ↑ Frontiers in Freshwater Science, Ratha Sor and others, Factors influencing fish migration in one of the world's largest inland fisheries (August 6, 2024)
- ↑ Cultural Survival Quarterly, Kayla Starr, The Key to Khmer Cuisine (June 19, 2009)