|Scientific Name:||Paretroplus nourissati (Allgayer, 1998)|
|Red List Category & Criteria:||Endangered B1ab(iii,v) ver 3.1|
|Assessor(s):||Ravelomanana, T. & Sparks, J.S.|
|Reviewer(s):||Randrianizahaisa, H., Rasoloariniaina, R & Velosoa, J.|
This species is known only from the Sofia river drainage in Madagascar. This species is known from Amboaboa and Mangarahara rivers. Unfortunately in the dry season, the Mangarahara river is completely dry. With an estimated Extent of Occurrence of less than 5000 km², a fragmented habitat, single location, and a continued decline in suitable habitat due to deforestation, dams, and drought, this species is assessed as Endangered. It is also subject to competition and predation from introduced exotic fish species.
|Previously published Red List assessments:|
Endemic to Madagascar, Paretroplus nourissati is described from specimens collected from the Amboaboa and Mangarahara rivers near their confluence, which is in the vicinity of the town of Mandritsara in northeastern Madagascar (Sparks 2008). The species is also reported to occur in neighbouring lakes, located a few kilometres from the confluence of the Mangarahara and Amboaboa rivers (de Rham and Nourissat 2002). Recent surveys found a subpopulation on the upper reaches of the Amboaboa River near the village of Marotandrano and another subpopulation near the village of Marovato on the Anjombony River (Ravelomanana unpublished data).
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Paretroplus nourissati is described from specimens collected from the Amboaboa and Mangarahara rivers near their confluence, which is in the vicinity of the town of Mandritsara in northeastern Madagascar (Sparks, 2008). The species is also reported to occur in neighboring lakes, located a few kilometers from the confluence of the Mangarahara and Amboaboa rivers (de Rham and Nourissat, 2002). Recent surveys found a population on the upper reaches of the Amboaboa River near the village of Marotandrano and another population near the village of Marovato on the Anjombony River (Ravelomanana, unpublished data).|
In 2013 at the confluence of Amboaboa and Mangarahara, it was difficult to get a single specimen of P. nourrisati. In Marotandrano, a big effort for half a day only yielded about twenty specimens (Ravelomanana, pers. obs.). Subsequent ichthyological surveys of the Amboaboa River found P. nourissati to be abundant in 2004, but greatly reduced in numbers in 2006, possibly as a consequence of the many years of severe drought that the region has experienced (P. Loiselle, personal commun.). The Amboaboa River was surveyed again in 2011 and P. nourissati was again found to be low in numbers of specimens collected.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:|
The Amboaboa and Mangarahara rivers near the type locality are shallow, clear (low in turbidity), and the current is swift, with many areas of small cascades and riffles. These rivers flow over large areas of exposed bedrock, and the substrate is generally rocky, with many exposed boulders, and interspersed with areas of sand. Paretroplus nourissati frequents shallow, rocky stretches with a swift current and riffles. it is a streamlined cichlid fond of hiding under rocks in riffles and cascades. The species is frequently collected in swift-flowing water only a few inches deep, where it hides under rocks (Sparks, 2008).
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Movement patterns:||Not a Migrant|
|Use and Trade:||This species is caught for local consumption.|
Paretroplus nourissati would seem to be vulnerable to increased fishing pressure and continued habitat degradation (Sparks, 2008). Regrettably, de Rham and Nourissat (2002) report that in the late 1990s a dam was constructed, financed by the World Bank, on the Mangarahara River upstream from its confluence with the Amboaboa to permit year-round rice cultivation, which essentially resulted in complete desiccation of the Mangarahara downstream of the dam during the dry season. This has resulted in the extirpation of native fishes for several kilometers downstream from the dam.
|Conservation Actions:||No conservation measures are in place for this species.|
|Citation:||Ravelomanana, T. & Sparks, J.S. 2016. Paretroplus nourissati. The IUCN Red List of Threatened Species 2016: e.T44494A58308011.Downloaded on 21 January 2018.|
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