Fish diversity in Pakistan and common threats

Abstract

Fishes are one of the most diverse group of vertebrates with more than 33000 species. Owing to variety of landscape, rivers and lakes provide the best habitat for fishes in Pakistan. They are identified on the basis of several visual characters. With advancements in machine learning, researchers from Pakistan have used a Fish-Pak data set to identify various fishes in local market [1]. Common fishes found in Pakistan are Rohu, Thaila, Mrigal, silver carp, grass carp and rainbow trout. In last four decades, several alien fish species like Cyprinus sp. Oreochromis sp. Hypophthalmichthys molitrix, Carassius Auratus, Aristichthys nobilis and Ctenopharyngodon idella have been introduced directly or indirectly in our natural river systems. Recent survey reports a total of 64 exotic species of fishes in Punjab, Pakistan. These alien fishes destroy habitat of native species and negatively impact fish fauna [2].

According to WWF survey, 86 species of the fish fauna is of special concern of fishes while 34 species have been declared as endemic. Furthermore, number of species having special IUCN status are 11, commercially important are 31, very rare species are only 8 in Pakistan.

Population of economically important species is declining due to overexploitation, pollution and habitat fragmentation. Industrial and municipal waste has been associated with metal contamination in muscle mass of fishes, which make them a hazard to consume [3]. Similarly, marble effluents are also a threat to fish population [4]. Therefore, possible measures for fish conservation needs special attention for its sustainable use and diversity.