Coelacanth (Latimeria Manadoensis) ancient fish are endangered,found manado bay.
Justification:
Latimeria menadoensis is only known from three locations in northern Sulawesi, Indonesia and very few specimens have been seen. It is thought to be naturally rare with a population of less than 10,000 mature adults. This is a slow growing species with low fecundity, and therefore is naturally susceptible to over-exploitation. Major threats are bycatch in deep set shark nets and hook and line fishing for deepwater groupers. There is no population information available and nothing is known about current trends. Due to small number of localities known, and the life history, suspected low population size, and threats from bycatch, Latimeria menadoensis is listed as Vulnerable under criteria D2 and C2a.
Geographic Range,Range Description:
This species is known from the Celebes Sea, north of Sulawesi in Indonesia. It is only known only from three localities. The first two specimins were caught on Manado Tua in September 1997 and July, 1998. Another was caught in Manado Bay in May, 2007. The third site is northern Suluwesi near Dondo Bay, slightly to the east on Tanjum Kandi. The animal from the Dondo Bay site was observed in the Jago submersible in November 1999. The Tanjum Kandi sighting was in June 2006 from the Fukushima Aquamarine Aquarium ROV.
Population:
The population status of this species is unknown. It is believed to be a naturally small population (suspected to be less than 10,000 mature adults) and rare. A population study has never been undertaken and the species is very rarely caught by fisherman. One experienced fisherman informed that during his life as a fisherman this species was caught no more than 30 times, or not more than one or two times per year (M. Erdmann pers. comm.). The growth of its population is likely to be very slow, similar to Latimeria chalumnae. The shark fishermen at Menado Tua Island generally catch 1-2 individuals of L. menadoensis once every 5-10 years as bycatch (Erdmann and Kasim Moosa, pers. comm.). In northern Sulawesi, all fishermen are aware of this species and would report it if caught.
Habitat and Ecology:
This is a demersal, non-migratory marine species found in deep water between 150-200m depth. It lives in water temperatures from 17-20°C. It is presumably found in rocky slopes and caves. Fricke et al. (2000) observed two specimens of 120 and 140 cm length in a deep carbonate cave at a depth of 155 m (water temp. 17.8-20.1°C). Latimeria menadoensis is presumed to be very slow growing and long lived, with very low fecundity (maximum of around 50 for congeneric species), similar to sharks. Females produce large, orange-sized eggs which hatch within the oviduct before the female gives birth to live young. The autopsy of the Sulawesi Coelacanth that was caught in May 2007 in Bunaken National Marine Park, showed that in fact the fish was pregnant. Scientists in Indonesia, France and Japan are currently conducting research to better understand the reproductive biology of this fish.Though scientists have never observed coelacanths feeding in their natural habitat, analyses of stomach contents of captured specimens have shown that their diet includes cuttlefish, squid, and various small to medium-sized benthic fishes – including lantern fishes, cardinal fishes and deepwater snappers.
Coelacanths can weigh up to 100 kg, though an average size is closer 30 kg.They may live to an age of at least 22 years.There are many unanswered questions about the ecology of Latimeria manadoensis.A unique combination of morphological features suggest that the coelacanth lineage is close to the origin of the evolution of early terrestrial, four-legged animals (tetrapods) like amphibians. The most remarkable of these features is the presence of seven lobed fins, unique among the living fishes. The paired fins move in an alternating fashion which resembles a horse in a slow trot. Other interesting features include a small secondary "epicaudal" lobe on its tail, an oil-filled notochord instead of a backbone, an intercranial joint which is thought to allow them to widen their gape when capturing prey, and a unique electrosensory rostral organ that may be used to detect prey. While their morphological features lead many scientists to believe the coelacanth lineage was the direct link to tetrapods, recent molecular evidence suggests that lung fish might be more closely related to tetrapods (University of California Museum of Paleontology, website).
Major Threat:
Latimeria menadoensis has a very low population size and its life history makes it a species with higher extinction risk due to slow growth and low fecundity. This is not a commercial species and has no food value, but is caught as bycatch by deep shark nets and by hook and line targeting deepwater snapper,This species is an extremely sought after aquarium fish, although no specimen has ever been successfully kept alive for aquarium display.
Conservation Actions:
This species is protected locally by Indonesian regulations and internationally by CITES, which includes all Latimeria species (CITES Appendix I, since 2000).
This species needs further research in all aspects of its ecology and biology and to determine the extent of its distribution, population size and trends. However it is an extremely difficult and expensive animal to study due to it's habitat time and deep water living.Shark nets were outlawed in Bunaken National Park which includes Manado Tua where the first individuals were caught.
(sources:Iucuredlist.org)
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