The conservation status of hypogean fishes

Hypogean fishes are susceptible to five main threats: habitat degradation, hydrological manipulations, environmental pollution, overexploitation, and introduced alien species. Because they are endemic to small areas and have small populations, any threat could have serious consequences. For these re asons most populations have been considered 'threatened' or 'vulnerable'. I nternational Union for the Conservation of Nature, and Natural Resources ha s produced five Red Lists of threatened animals since 1977 and have listed seven, eight, 31, 31 and 63 hypogean fishes, respectively, in some threat c ategory. Before 1994 the categories were qualitative and workers could asse ss the same species in different ways. In 1994, a new set of quantitative c ategories were published. The 1996 list was the first to use these categori es and three hypogean species were listed critically endangered, two endang ered, 46 vulnerable and 12 data deficient. Some of these categories are inc orrect or inappropriate and most of the data deficient ones can now be cate gorised. All 85 known species are categorised here and reasons given for th eir placements. The current list has three critically endangered, none enda ngered, 73 vulnerable, four near threatened, one least concern and four dat a deficient. Some species are relatively well known, others are poorly know n. Some are receiving conservation attention, most receive none. A few capt ive populations have been established, some of which are breeding. Few popu lations could be restocked if extirpated. Knowing where to direct conservat ion efforts is a problem since morphological 'species' are proving to be fr om more than one epigean invasion and therefore represent more than one spe cies. Hypogean fishes merit protection but they may not receive more than c ursory protection.