Distribution Pattern and Brood Parasitism Characteristics of an Endangered Fish, Pseudopungtungia nigra, in the Geum River Basin, South Korea

Abstract

Pseudopungtungia nigra is an endangered fish species endemic to South Korea with a narrow habitat range in the Geum River basin. Understanding their long-term distribution (25 years, 1997–2021) and breeding characteristics can contribute to the conservation and habitat management of endangered species in this area. We analyzed long-term data on environmental factors and fish in the Geum River and investigated the invading and spawning characteristics of P. nigra using underwater cameras. From the study results, P. nigra indicated no clear dispersion or decline trend in the Geum River. P. nigra exhibits brood parasitic behavior in the nest of Coreoperca herzi, another species found in the same region. C. herzi males protect their nests during the spawning period, and the eggs spawned by P. nigra in the nests of C. herzi are also protected by C. herzi. This high dependency of P. nigra on C. herzi possibly contributed to its distribution range in the Geum River basin. Habitat changes caused by anthropogenic interventions during the study period did not significantly affect the distribution of P. nigra. The results indicate that the distribution pattern of P. nigra is influenced by the distribution of sympatric fish species rather than environmental changes.