Thirty four species of mosquitoes (Diptera: Culicidae) were collected across three phytogeographic zones; tropical (300 to 1000 m), sub tropical (1000 to 2000 m) and temperate (2000 to 3000 m) in the Garhwal region of India. They included 5 genera: Aedes, Anopheles, Armigeres, Culex and Uranotaenia. Of these, the immature forms of 23 species were recovered from different breeding habitats. The larval habitats were seepage pools, river beds, rice fields, tanks, forest pools, ditches, streams, rock holes, tree holes, intradomestic containers and shallow pits. Three groups and two separate individual species were associated, based on breeding habitat similarity by means of cluster analysis. The characters taken into consideration for classification were natural/artificial, temporary/permanent, shady/lighted, vegetation, movement and turbidity. Breeding habitats such as streams and rock holes were the richest habitats shared by 18 mosquito species followed by seepage pools harboring 16 species of mosquitoes. The lowest species diversity (6 species) was recorded from shallow pits. Generally, all the collected species were found in natural habitats in quiet/stagnant conditions at a depth of 0.1–0.5 m. Generally, the maximum number of species preferred partially shady and temporary water habitats. Moderate vegetation and clear water habitats also had a diversity of mosquito species. Culex mimeticus Noe and Anopheles maculatus Theobald had the highest association coefficient (0.941) followed by Anopheles stephensi Liston and Anopheles vagus Donitz (0.884). The highest negative association (-0.30) was found between the species of Culex vishnui Theobald and Culex brevipalpis (Giles). There were a few species of mosquitoes for which only immatures were collected. Phytogeographically, the zones of lower elevation shared higher species abundance than the higher elevation.

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Background and Objectives: Knowledge about the movement of adult mosquito vectors in endemic and epidemic areas is valuable for understanding disease transmission dynamics providing a phenomenon of the behaviour, biology, demography, ethology and patterns of disease transmission.Methods: With this respect, the dispersal range of Ae. aegypti and Ae. albopictus had been conducted based on mark-release-recapture method in the campus periphery of Dayanand Anglo Vedic Post Graduate College, Dehradun, Uttarakhand, in the month of June 2015.Results: Aedes recaptured from various distances consist of 21.21% within 20 m, 45.45% within 50 m and 72.72% within 80 m distance from the release point. However, mean dispersion distances of Ae. aegypti and Ae. albopictus were found to be 31.78 m and 97.36 m respectively. The R 2 value was found higher in case of Ae. aegypti (0.6795) than Ae. albopictus (0.3597), indicating that Ae. albopictus dispersed more than Ae. aegypti. Using the non-parametric test, Mann-Whitney test for two independent samples, the results showed there is no significant difference (p ≤0.05) of flight range of the two species (z=−0.7181, p=0.47152 ). Interpretation and Conclusion:Less recapture rate of male than female justified the fact that mosquitoes will be forced to fly greater distances than they normally would if released at a point distance from any of the enumerated ovipositing items. From the present study, it was suggested that adulticiding should be intensified up to 100 m in and around the periphery of the reported dengue incidences for a week. Busy roads or unshaded areas may serve as barriers to movement of Aedes species and thus water holding containers should be targeted for more intensive adulticiding.

On examining 144 specimens of Labeo rohita (Ham.) for parasites occurrence; as many as 34 fish were found positive to harbour ciliophorans (Trichodina sp. and Ichthyophthirius multifilis Fouquet, 1876), monogeneans (Haplocleidus vachi Tripathi, 1959 and Dactylogyrus glossogobii Jain, 1960), trematode (Allocreadium mahaseri Pandey, 1939), nematode (Camallanus (Zeylanema) anabantis Pearse, 1933) and acanthocephalan (Sachalinorhynchus sp). Highest prevalence was shown by platyhelminthes (18.75%) followed by ciliophorans (10.41%), nematode (4.16%) and acanthocephalan (2.77%) in succession. Maximum mean intensity and abundance has been shown by C. (Zeylanema) anabantis Pearse, 1933 while the monogenean H. vachi was on the 2nd rank. On the other hand, the least intensity and abundance was shown by Ichthyophthirius multifilis. The prevalence was recorded more in monsoon (52.77%) followed by post-monsoon (22.22%), summer (19.44%) and winter (8.33%) in succession. Further, the unit-wise intensity of parasites was recorded more in males than the females.

The present study is based on screening of food preference by the indigenous fish under its natural condition. The gastrointestinal contents as an indicative of effective bioregulatory activity envisage the selection of a larvivorous fish. As many as 32 species of fishes were collected from their natural habitats at Imphal and Bishenpur districts in Manipur State between August 2007 to February 2008. Faecal drops of active fishes revealed remains of larvae / pupae of mosquitoes. However, the food types in 26 species of fish comprised larvae / pupae of mosquito, algae, weeds, tadepole fishes, crustaceans, insects, gastropods, worms and detritus / debris. On the basis of food preference Aplocheilus panchax, Polyacanthus fasciatus and Puntius manipurensis have been considered as most potent larvivorous fish of the study area.