A wife claimed that she saw the species in the market in 2016. Another fisherman reported that he caught one piece of B. A fisherman captured this species in 2006. Some claimed that this species is already very rare. Most key local fishermen, fish vendors and housewives confirmed the disappearance of this species in the lake and fish markets for many years. Local knowledge through Key Informant Interviews was also sought to supplement data from these fish landing surveys. In 2008 (Ismail 2014) and in 2015 (DENR 2015), direct field sampling, market survey and fish landing monitoring did not find this species. In May 2016-March 2017, this species was not also encountered after about a year of fish landed catch monitoring conducted every other day in major fish landing sites representing northwestern, northeastern, southwestern and southeastern parts of Lake Lanao (Torres 2018). In November 2007, approximately 100 individuals were obtained from the markets for fecundity analysis (Mangondato 2008). After the 1990-1991 survey, no major surveys were conducted in Lake Lanao until mid-2000s due to unstable peace and order around Lake Lano and lack of research funding. In a span of 17 years, this represents over 90% reduction in fisheries catch data. Fisheries production in 1990-1991 declined, constituting only 9% (22.442 MT/yr) of the total fisheries production in Lake Lanao (Escudero 1995).
In 1990-1991 survey, sampling months were not indicated but it is assumed that it is likely for a year of monitoring just like in the 1982-1983 survey of Escudero and Demoral (1983). In 1982-1983, its fisheries production for a year decreased significantly, representing only 17% (92.019 MT/yr) of the total catch (Escudero and Demoral 1983). In 19-1977, this species was the most abundant species with 49% (approximately 424 MT/yr) and 55% (approximately 412 MT/yr) contribution to the fisheries production, respectively (Escudero et al.
Historical catch data in 1970s, 1980s, and 1990s clearly showed the gradual decline of the fisheries production of B. The estimate of the population of Barbodes sirang is inferred from the changes in catch statistics. The estimated extent of occurrence (EOO) of this species is 441 km 2 and the area of occupancy (AOO) is 358 km 2. The lake has a maximum depth of 112 m, a mean depth of 60.3 m, a replacement time of 6.5 years, a lake surface altitude of 702 m, and a surface area of 357 km2 (Frey 1969). Together with its only outlet (Agus River), it serves as a major source of hydroelectric power, supplying the majority of the electricity needs of the entire Mindanao (Escudero 1995, Rosagaron 2001, Naga 2010, UPLB-DENR 2014). Lake Lanao is the largest lake in Mindanao and the second largest lake in the Philippines. Location Information Barbodes sirang is endemic to a single location in Lake Lanao, Lanao del Sur, Mindanao, Philippines. A strategic regular water quality survey and monitoring are needed to identify and reduce or eliminate pollution hotspots. Eradication programs of invasive species in Lake Lanao should be a priority. Breeding and stock enhancement programs are highly recommended to restock the lake. A comprehensive information and education campaign program should be developed and implemented to increase public awareness and generate public participation for high species recovery. A species recovery program should be immediately launched.
More specifically, a thorough survey in the southern part of the lake to verify the presence of this species is needed.
Extensive and intensive surveys are urgently needed to locate surviving individuals of this species. A comprehensive biodiversity assessment in the lake is imperative. Considering the unstable peace and order around Lake Lanao, a combination of ex-situ (offsite) and in-situ (onsite) conservation approaches under community-based resource management with active participation of the 19 local government units surrounding the lake is highly recommended. Conservation is urgently needed to save this species from extinction. Conservation of this species does not exist.
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