Ichthyofaunal diversity in Bachan Gad and Kakda streams of the Mid-himalayan Ganga river system of Garhwal in relation to stream gradient and distance

The present study was carried out to investigate the comparative seasonal distribution and relative abundance of fish fauna of streams Bachan Gad of river Alaknanda and Kakda Gad of river Mandakini of Mid-himalayan Ganga river System. Total length of the Bachan Gad is 14.5 km from origin to the confluence at main river Alaknanda with an altitudinal variation from 605.94 to 1418.23m (a.s.1), whereas, total length of the Kakda Gad is 15.5 km. from origin to confluence at main river Mandakini with altitudinal variation from 984.50 to 1993.70 m (a.s.1). Total 23 species from Bachan Gad and 20 fish species were identified from Kakda Gad. The differences in the availability of fish-fauna were directly related to the nature of the profile and slope of tributaries; which affects the migration and breeding grounds of the fishes inhabited in the main river Alaknanda and Mandakini of Ganga river system. Variation in the availability of fishes has been recorded from different sites of the stream. In streams and rivers the changes take place along their length is directly related to the eco-physico-chemical nature (water depth, current, substratum etc). All these factors which change along the length of streams are also the factors which control the distribution of the various sections of the biotic fauna and flora

Establishment of population of introduced brown trout (Salmo trutta) co-related to their feeding habits in river Asiganga, district Uttarkashi, Uttarakhand

Uttarakhand is considered as one of the freshwater fish biodiversity zone within India and the aquatic biodiversity here is threatened primarily due to anthropogenic activity and introduction of non-native fishes.  Colonization and invasion of new aquatic habitats are common in nature as a result of climatic or geotectonic events but humans provide additional artificial pathways by which introduced non-native fishes can overcome biogeographic barriers. Here, in this paper, we assessed the i) factors assisting establishment of introduced brown trout’s (Salmo-trutta) population in river Asiganga and other fresh water systems in district Uttarakashi, ii) attributes of brown trout’s dietary habits that are helping them establish their population by analyzing the stomach contents of brown trout and, iii) food preferences of brown trout. As evident from our studies it is found that fish fingerlings is the food of choice and based on the morphometric assessment most of these fingerlings being preferred as food are that of an endemic species Schizothorax.  Brown trout does eat benthos but Selectivity Index data suggest that these benthos are not a preference but lie in the neutral zone as most of the values are between -0.25 to 0.25. Different feeding preferences and reduced water level in pockets of rivers for long distance migration, seems to be major factor in establishment and spread of brown trout which in turn is threatening the endemic fish species of Uttarakhand.  

AN INCIDENCE OF EYE AND SNOUT ABNORMALITY IN A HILLSTREAM MINOR CARP BARILIUS BENDELISIS (PISCES : CYPRINIDAE)

The paper deals with a report on an abnormal specimen of Barilius bendelisis (Hamilton) with an eye and snout abnormality. Morphometric characters of the abnormal specimen and its comparison with the normal fishes is discussed in the paper

The profile of river ecosystem, food and feeding habits of hill-stream fishes and consequences of recent environmental degradation in Garhwal Himalaya

The Garhwal region of the Central Himalaya (in the Uttar Pradesh, India) offers an unique physio-topographic, climatic and environmental features. The glacial-snow-fed and non-glacial-fed or spring-fed rivers of the area makes the upper basin of the Ganga River system of North India (being characterized by low water temperature steep gradient fast water current, high turbulence etc.). There are 65 fish species (belonging to 9 families of teleosts) reported so far. Various biotic communities (planktonic, benthic, nektonic and neustonic), detritus, debris, sand particles are being used as food matters by herbi-, herbiomni-, carnivomni-, carni-, larvi- and piscivorous fishes. During recent years, hillstream environment has deteriorated owing to excessive deforestation, multipurpose river valley projects, over grazing, forest fires, modern tourism, over exploitation of natural resources

Effects of some plant toxins on feeding and growth rate of Barilius bendelisis (Ham.)

Tests conduced in the laboratory indicated that feeding rate in B. bendelisis exposed with safe concentrations of Aesculus indica (10 mg-1) Engelhardtia colebrookiana (8 mg-1) Lyonia ovalifolia (20 mg-1) and Zanthoxylem alatum (2 mg-1) was reduced 37.3%, 39.0%, 17.12%, 47.3% (natural) and 33.5%, 48.0%, 16.3%, 51.5% (artificial) respectively as compared to the non toxicated fish. Growth analysis made at chronic level showed that initially, there was a decline in the weight of fish due to less uptake of food and gradually the length was retarded. The study suggested that since the active compounds of piscicidal plants, at safe concentration level affected the laste system of fishes. Consequently the rate of feeding was inhibited. The less feeding and metabolic disorders found expression as a decline in the total growth of treated fish. It was evident that the principles of A. indica and E. colebrookiana were comparatively more growth inhibitors than L. ovalifolia and Z. alatum