Basti Damar gad is a spring fed tributary of river Mandakini which is quite conducive for biodiversity. As the stream was unexplored, it was taken as an opportunity to investigate the stream for its habitat quality and diversity of benthic organisms. Stream was studied at two different spots one in more or less rhithron zone and the other one in near potamon zone during the year 2019-20. Comparatively, the Spot No 2 had more density (836 individules.m-2 ) and diversity (28genus) of macrozoobenthos than spot No 1 (127 individules. m-2 and 28 genus) which may be due to better substratum heterogeneity dominated by mixed forest, small gravels, small bolder, low water velocity, high water temperature, low canopy of stream area and good survival rate of periphyton on bottom in the stream. Also the water quality at this spot (comparatively low current velocity, moderate temperature, good amount of DO and high alkalinity and pH) was supportive for flourishing biota. The observations were statistically analysed using coefficient of correlation, coefficient of determination, regression, species similarity, dominance and diversity indices.

Barilius bendelisis (Hamilton) is an ornamental fish. The feeding ethos of fish is of great concern for its culture and breeding. Strauss selectivity index is simply the unweighted difference in proportion (L= ri - pi) of the prey item in the gut and the environment. It ranges from   -1 to + 1 with a positive value indicating preference and the negative value indicating avoidance or inaccessibility. Three length-groups (1 < 5cm, 5-10cm. and > 10cm.) were analyses in current study. Barilius bendelisis has been found to accompany a change of food habit with more emphasis on insect items in higher length groups.  It had been noticed that in Barilius bendelisis feeding ethos showed dipterans larva as more available digestible food part in gut portion than ephemeroptera and trichoptera larvae in all different size groups.