Lake Tondano

Lake Tondano is the largest lake in North Sulawesi, sitting at 600 metres above sea level in the highlands about 36 kilometres south of the provincial capital, Manado. It has long served the Minahasa people as both a food source and a transport route, and the lakeside town of Tondano, capital of Minahasa Regency, has grown up around its northern shore. The lake is home to two species found nowhere else: Tondanichthys kottelati, a small halfbeak fish, and Phyllodiaptomus sulawesensis, a species of calanoid copepod first described from Tondano's waters. Both are recorded in the FishBase reference database devoted to global fish biodiversity, which treats Tondano as a distinct evolutionary pocket much like Poso, Matano and Towuti further south, even though it sits in a very different, much shallower kind of basin. That shallowness has become the lake's defining modern problem. Measurements cited in a 2010 Jakarta Post report on the lake's condition found average depth had fallen to around 12 metres, down from roughly 40 metres recorded in 1934, a decline discussed locally in connection with sediment washing in from the surrounding slopes and pressure from fish-cage farming in the shallows. Local and national authorities have since discussed dredging and catchment programmes to slow the trend, a subject that comes up regularly in regional tourism-forum discussions about the lake's future. For now, Tondano remains a working lake rather than a purely scenic one: fish cages dot large sections of the water, and the shoreline road connecting Tondano town to the Bukit Kasih volcanic park nearby gives sweeping views down over the basin. Manado's Sam Ratulangi International Airport puts the lake within an easy day trip of the coast, making it one of the more accessible entries on this list even as its long-term health remains an open question.