The ecological impact of tilapia cage culture in Sampaloc Lake, Philippines
Abstract
Sampaloc lake showed imminent biological death as a consequence of intensive tilapia farming in floating net cages. The progressive disappearance of dissolved oxygen in the entire water column may be an irreversible trend due to continuous feeding. The high amount of BOD5 and the near toxic concentration of total ammonia and total sulphides are ominous signs. Other ecological changes in the lake are the non-appearance of Microcystis bloom, change in phytoplankton composition, number, and species diversity.
Source
In: Chou, L.M., Munro, A.D., Lam, T.J., Chen, T.W., Cheong, L.K.K., Ding, J.K., Hooi, K.K., Khoo, H.W., Phang, V.P.E., Shim, K.F., Tan, C.H. (eds.). The Third Asian Fisheries Forum. Proceedings of the Third Asian Fisheries Forum, 26-30 October 1992, Singapore. Manila, Philippines: Asian Fisheries Society. pp. 413-416
Publisher
Asian Fisheries SocietySubject
Type
Conference paperCollections
- Conference Proceedings [283]
Related items
Showing items related by title, author, creator and subject.
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Article
Tilapia cage culture and the dissolved oxygen trends in Sampaloc Lake, the Philippines
-Environmental Monitoring and Assessment , 1993 - Springer VerlagThe 28-hectare tilapia cage culture that occupied the 104-hectare Sampaloc Lake, a crater lake, shifted to intensive method in 1986 when tilapia growth slowed done at the beginning of 1982. Thus, commercial feeds became the main source of allochthonous organic matter in the lake. Total feeds given annually for the 28-hectare cage culture at 3 croppings per year amounted to 5250 tons. At feed conversion ratio of 1 : 2 a significant portion of the feeds given ended as organic wastes in the lake. In 1988, tilapia cage operators began experiencing their worst occurrences of fishkill, worth millions of pesos. An assessment of the dissolved oxygen condition of Sampaloc lake in late 1989, 1990 and mid-1991 showed ominous trends which might adversely affect the use of Sampaloc lake for fishery. -
Conference paper
The status of tilapia aquaculture in Lake Sebu, South Cotabato
- In Conservation and Ecological Management of Philippine Lakes in Relation to Fisheries and Aquaculture: Proceedings … Seminar-Workshop held on October 21-23, 1997, INNOTECH, Commonwealth Ave., Diliman, Quezon City, Philippines, 2001 - Aquaculture Department, Southeast Asian Fisheries Development Center; Philippine Council for Aquatic and Marine Research and Development (PCAMRD), Department of Science and Technology; Bureau of Fisheries and Aquatic ResourcesTilapia culture in Lake Sebu started in the early 1970's and is now considered the backbone of the economy and major driving force of the development of the Municipality of Lake Sebu. About 19% of Lake Sebu's 354 ha water area is used for aquaculture. The present tilapia production system is not as intensive as in other lakes in the country. The daily 3-ton tilapia harvest is marketed in the different towns within the province and in neighboring provinces. Municipal Ordinance 01, Series of 1994 regulates fish cage establishment within the lake. The local government unit launched a semi-annual 'Oplan Linis', a clean up operation to remove floating debris, water hyacinth, and other vegetation along the lakeshore. Reforestation has been implemented as part of the watershed management program. For centralized marketing and effective collection of revenues, a fish port was opened in January 1997. The tilapia industry in Lake Sebu is now confronted with several setbacks. Poor-quality seeds require a longer culture period and, despite higher inputs, still result in low production. Fish kills, locally termed 'kamahong', are becoming more frequent and devastating. Market competition is another problem. Producers of intensively fed tilapia from Lake Sebu have to contend with a large volume of unfed and low priced tilapia from Lake Buluan (Lutayan area). -
Book
Tilapia cage farming in lakes
- 1984 - Aquaculture Department, Southeast Asian Fisheries Development Center
Series: Aquaculture technology series / SEAFDEC Aquaculture Department; No. 1Guidelines are given for the cage culture of tilapia in lakes in the Philippines. The following major topics are covered: site selection; cage design and layout; operation and management tips.
