Fish introduction in Latvia – inventory, present status and prospects

Current issue: Volume 24, No. 1 (2024)

FISH INTRODUCTION IN LATVIA- INVENTORY, PRESENT STATUS AND PROSPECTS

Jānis Birzaks*

DOI: https://doi.org/10.59893/abud.24(1).002

Birzaks J. 2024. Fish introduction in Latvia – inventory, present status and prospects. Acta Biol. Univ. Daugavp., 2024(1): 9-28.

Abstract

The article reviews the history of fish introductions in Latvia, their aims and results, their potential impact on the local ichthyofauna and future prospects. There have been three periods of fish introductions in Latvia: a) from the Middle Ages to the 1940; b) from 1940 to 1990; c) from 1990 to the present. The peak of fish introductions occurred after the Second World War until 1990. Most of these species originate from the European and Asian part of the former USSR. A total of 28 fish species have been introduced in Latvia; of these, four species have naturalized. Only two of the introduced species are now relatively widespread, while one is invasive. Aquaculture and fish stocking to establish new fisheries were the key drivers for the introduction of non-native species in Latvia. These attempts in Latvia have largely failed. Aquaculture is the only fishery sector in Latvia that has benefited from fish introductions in terms of increased diversity production. Our results show that the impact of earlier introductions in Latvia has so far not had a significant impact on native species and biodiversity. However, taking into account the possible effects of climate change in interaction with anthropogenic modifications, it could increase: a) with the introduction of new species from neighbouring countries and b) with the establishment of self-sustaining populations.

Keywords: Latvia, introduced fishes, freshwaters, impacts, management.

*Corresponding author: Jānis Birzaks. Institute of Life Sciences and Technology, Vienības Str. 13, Daugavpils LV- 5401, Latvia, E-mail: janis.birzaks@du.lv