Length-weight relationship: eight species of Cyprinidae from river Panjkora, Khyber Pakhtunkhwa, Pakistan

Seven hundred and twenty four fish specimens were captured from March to September 2016. The materials used in the current study were cast nets, hand nets. Eight cyprinid fish species were studied for their length-weight relationships. Parameter b in the LWR was 3.03, 3.06, 3.02, 2.29, 2.82, 3.43, 2.73 and 2.47 for Schizothorax plagiostomus, Schizothorax esocinus, Racoma labiata, Tor putitora, Barilius vagra, Garra gotyla, Puntius ticto and Arassius auratus respectively. Current study is the first attempt on the LWRs of cyprinid species, provide a baseline approach for conservation and /management of local fish fauna of economic importance.

Partition among niche and neutral explanations for metacommunity patterns of fish from Cerrado streams

The Species-Sorting concept, one of the models developed to explain patterns in metacommunity structure, suggests that relationships between biological communities and environmental conditions is the basic means of the species selection processes. A second concept is Neutral Theory, and the idea of neutral dynamics underpinning metacommunity structure, cannot be overlooked. The third mechanism is the Mass-Effect concept, that focuses on the interaction between environmental condition and neutral effects. In the present study, we partitioned fish communities in streams between niche and neutral theory concepts, identifying the best representation of metacommunity structure, and assessed if linear and hydrographic distance were equivalent in the representation of neutral processes. The result points to the importance of species sorting mechanisms in structuring fish communities with neutral processes best represented by the linear distances. These results are important for the fish fauna conservation leading to three considerations: (i) the variation of the landscape and habitat is important for the stream fish, (ii) the natural barriers are an important landscape component to be considered, and (iii) the artificial barriers (dams and impoundments) need to be planned taking in account the catchment basin as the landscape unit.

Impact of alien fishes on the distribution pattern of indigenous freshwater fishes of Punjab, Pakistan

Pakistan is the country with mega freshwater fish diversity of native and alien species. In the presence of enormous native fishes varies species of exotic fishes have been introduced into the freshwater bodies of Pakistan which are competing with native freshwater fish fauna and making them deprive of food and habitat as well. Intentional or accidental introductions of animals, plants and pathogens away from their native niche is considered as major leading problem for biodiversity of invaded habitat. Three years study (from January 2017 to December 2019) was conducted in freshwater bodies of Province Punjab, Pakistan. Study was designed to know exotic species impacts on the distribution of native species of fishes. During current survey a total of 68 (indigenous and exotic) fish species belonging to 14 families were recorded from head Qadirabad, head Baloki, Islam headworks and Rasul barrage. Statistical analysis showed that Shannon-Wiener diversity index was the highest (1.41) at both Rasul barrage and Islam headworks but, invasive species were present in very less number in these study sites i.e. Oreochromis mozambicus, O. niloticus, Hypophthalmichthys nobilis, Carassius auratus, Ctenophryngdon idella, Cyprinus carpio and H. molitrix. The diversity index showed that comparatively low diversity was present in both area head Qadirabad (1.30) and head Baloki (1.4) due to high pressure of invasive species. Direct observation of species and statistical analysis showed that aliens’ species produced negative impact on the local fish fauna diversity, evenness, and numbers. It is concluded that many factors are impacts on the diversity of native fishes, but alien (invasive) species also play a major role to reduction of native species, because aliens’ species produce competition for native species. So it is urgent need to analysis the aliens and native food web and roosting sites in Pakistan, in future.

STUDY ON ICHTHYOFAUNAL DIVERSITY IN RELATION TO PHYSICO-CHEMICAL PARAMETERS OF MANAKONDUR FRESH WATER LAKE OF KARIMNAGAR DISTRICT, TELANGANA STATE, INDIA

Freshwater bodies are one of the most common and stable habitats of biosphere. The freshwater habitats have their own physico-chemical and biological characters which are subjected to modify by local conditions and physiographic features. The water quality parameters have a great influence on the growth and other factors of aquatic organisms. Therefore, the lentic water body gives a good source for fisheries. The present investigation deals with limnological and physico-chemical parameters and their influence on Ichthyofauna abundance in Manakondur fresh water Lake at Karimnagar District, Telangana State. The study was carried out for a period of one year i.e., from June, 2020 to May, 2021.The investigation was focused on the determination of hydro-chemical parameters such as Water temperature(19.0-31.0ºC),Transparency(18.50-44.30cm),TDS(200-350mg/l),PH(7.5-8.3),DO(5.2-12.0mg/l),Co2 (3.0-9.2mg/l),TH(110-210mg/l),TA(165-300mg/l),CL(35.00-50.20mg/l),Po4 (0.02-0.16mg/l),No3 (0.02-0.14mg/l) and BOD(2.5-7.0mg/l).The study was made to recorded fish fauna available. Total 33 species of fishes were collected and identified during the study period which belongs to 6 orders, 12 families and 18 genera. The order Cypriniformes was dominant with 15 species, followed by Siluriformes (8 species), Osteoglosiformes(2 species), Perciformes(4 species), Channiformes(3 species), Perciformes(4 species) and Antherniformes(1 species) were identified. Order wise percentage composition is Cypriniformes (17%), Siluroformes (34%), (Osteoglossiformes(8%), Perciformes (25%), Channiformes (8%), Anthrniformes (8%) In the light of recent literature, the data has been discussed and it is concluded that limnological and physico-chemical parameters in this reservoir are most comply with suitability of human consumption and favourable for fishery. In the light of recent literature, the data has been discussed and it is concluded that limnological and physico-chemical parameters in this reservoir are most comply with suitability of human consumption and favourable for fishery.

Aquatic bioresources of artificial water bodies in Republic of Mordovia (case of Turgenev Reservoir)

On the territory of the Republic of Mordovia there are found more than 220 multi-purpose ponds and water reservoirs built on the watercourses. The Turgenev Reservoir on the Alatyr River is a typical channel artificial reservoir. The results of comprehensive fisheries research for the period of 2009–2015 are presented. Analysis of the fod der base showed a significant underutilization of zoobenthos and phytoplankton. Using the average indicators of the fodder base over the above period, the production capacity of the reservoir fodder base was calculated, which amounted to 39.69 tons or 405 kg/ha. According to the results of research fishing with fry seine, the ichthyomass of small fish species and juveniles under the age of two years is estimated by years at the level of 8 tons or 73–91 kg/ha. According to the results of net catches, the ichthyomass of the commercial fish fauna is at the level of 6.3 t or 64 kg/ha; the total ichthyomass is 146 kg/ha. The possible catch of mainly small fish in the Turgenev Reservoir can make 5–7 tons, and in total in the Republic of Mordovia in the multi-purpose water reservoirs - about 260 tons. Due to the reconstruction of ichthyofauna at the expense of a free food base, reproduction, fish- and water protecting measures the catches of marketable fish in ponds and water bodies of Mordovia can reach 1000 tons. The artificial reservoirs of the republic have a significant regulated potential of the aquatic biological resources for the low-water regions of Central Russia both providing the population with freshwater fish and creating the conditions for active and useful recreation on the territory near the water reservoirs: developing facilities for sport and amateur fishing and tourism.

Past, Current and Future of Fish Diversity in the Alakol Lakes (Central Asia: Kazakhstan)

The aboriginal ichthyofauna of the Balkhash basin consists mainly of endemic fish species. By the end of the last century, indigenous fish species were driven out of Lake Balkhash and the Alakol Lakes remain the largest refuges of aboriginal fish fauna. Knowledge of regularities of the modern distribution of the indigenous fishes is crucial for biodiversity conservation as well as restoring aquatic ecosystems. The modern diversity of fish species was investigated there in this study. Significant changes for the indigenous and some alien fish distributions were revealed in contrast with earlier known data. Canonical correspondence analysis (CCA) was used to study the relationships between habitat characteristics and species abundance. Water mineralization and maximal observed water temperatures were estimated as the main environmental variables in fish distribution at the local scale. Habitat change leads to fish fauna homogenization as a result of rare species extinction and alien penetration. Growing human population and poor water management make the future of the indigenous fishes unpredictable.

New records and range extensions to the Costa Rican freshwater fish fauna, with an updated checklist

The knowledge of the Costa Rican freshwater fish fauna continues to grow given the discovery of new taxa, the recognition of taxa resurrected from synonymy and the corroboration of new country records and new range extensions. Moreover, recent advances in the understanding of the phylogenetic relationships and status of many supraspecific groups have led to numerous taxonomic and nomenclatural changes. Given this, the purpose of this paper is to update the known composition, distribution and clasification of the Costa Rican freshwater fish fauna taking as reference the most recent list for the country published by Angulo et al. (2013). A total of 23 new country records (i.e., species; distributed in 17 families and 21 genera), 33 new range extensions (distributed in 20 families and 30 genera) and several nomenclatural changes are reported, illustrated and discussed here. An updated and annotated checklist of the freshwater fishes of the country (including data for a total of 283 species, 13 of which are exotic, distributed in two classes, 27 orders, 55 families and 136 genera) is also provided.

Commercial exploitation of Kуiv reservoir as a fishery water body (a review)

Purpose. To analyze an array of special scientific literature and summarize the obtained information on the commercial exploitation of the Kуiv reservoir as a fishery water body. To review main abiotic conditions of the reservoir, which exist and form the specificity of its commercial use by the fishery industry of Ukraine. To highlight the historical course of their impact on the fish fauna of the Kyiv Reservoir and general forecasts for its future transformations. Findings. An overview of scientific publications devoted to the specifics of commercial exploitation of the Kуiv reservoir as a fishery water body from the moment of its creation to the present day were presented. In particular, following was analyzed: hydrological regime, color and chemical composition of water, oxygen regime, accumulation of heavy metals, formation of bottom sediments and landscape. In addition, the radioecological situation in the reservoir was anazyed, both general and in three most significant areas for fisheries — in bottom sediments, macrophytes, and fish fauna. The literature data on the specificity of the above-mentioned abiotic factors in this reservoir, which form the hydro-ecological feature of this reservoir, were generalized. The main directions of their influence on the ichthyofauna of the Kуiv reservoir, which affect the possibility of its commercial exploitation, were described. The share of anthropogenic origin in the composition of the above-mentioned abiotic factors and the consequences of its impact were highlighted. The perspective ways of further development of the Kiev reservoir as a fishery water body of strategic importance for Ukraine were shown. Practical Value. The review may be useful for scientists, PhD students, students, government authorities, and private entrepreneurs involved in research process or exploatation of aquatic living resources in internal water bodies, primarily in the Kуiv reservoir. Keywords: Kуiv reservoir, fishery water body, hydrological regime, water chemical composition, water oxygen regime, heavy metals, bottom sediments, landscape formation, radioecological situation.