The Jullien's Golden Carp is one of the rarest and most highly valued freshwater carp in the world. It is also one of the largest cyprinids in Peninsular Malaysia, measuring at least 120 cm in length (Zakaria et al., 2012). It is scientifically known as Probarbus jullieni, or commonly known as temoleh, temelian or esok in Malay. This species is distributed in Southeast Asian river basins encompassing Thailand, Cambodia, Vietnam and Malaysia. In Malaysia, it is found in lowland river basins in Pahang, Terengganu and Perak.
One of the interesting features of this fish is its pharyngeal teeth which consists of one row of four teeth (Zakaria-Ismail et al., 2019). It has a small mouth and a long gut. The body of this fish is elongated and it has an attractive golden colouration with five deep black, longitudinal stripes and a uniformly white abdomen. Normally, adults and larger juveniles have much more red and sometimes yellow coloration on the head, body and fins (Froese & Pauly, 2019).
In Malaysia, the spawning season of the Jullien’s Golden Carp is from February to April (Anonymous, 2020). During this time, all fishing is prohibited. Also, the mature fish will migrate upstream to specific spawning areas. Until now, not much is known about the real age of maturity (Zakaria et al., 2012). In some reports, the weight of mature males in the wild range from 5 to 20 kg, while mature females are larger and weigh from 10 to 50 kg. However, under captive rearing conditions, the male and female brood stocks presently available in the market place range between 7 and 15 kg, respectively (Mattson et al., 2002). This fish species is omnivorous; its diet includes zooplankton, aquatic plants, fruits, invertebrates, molluscs, shrimps and crabs (Baird, 2006).
Numbers of this species have dropped significantly in the Perak River Basin mainly because of the development of hydropower in the spawning sites, and habitat degradation as a result of land clearing and deforestation (Bair, 2006). Due to this, the conservation status of this freshwater fish has been elevated from Endangered (EN) to Critically Endangered (CR) in the IUCN Red List of Threatened Species in 2019 (Ahmad, 2019). Also, this freshwater fish is listed in Appendix I in the Convention on the International Trade in Endangered Species (CITES), as it is threatened with extinction. Trade in specimens of these species is permitted only under exceptional circumstances but not for commercial purposes, and which do not harm the survival of the species (CITES, 2019). Artificial reproduction methods are being carried out in efforts to increase its population but as this fish grows slowly, it may take years for them to mature. Because of this and its high commercial demand, the price for this fish can reach between RM65 and RM100 per kg. Due to its CR conservation status, cultural and biological value, proper management and conservation of this species is a must in order to prevent its extinction.