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People of Chhattisgarh have a symbiotic relationship with the forest. About 44% of the geographical area of the state is covered under forests. The state of Chhattisgarh being placed in Deccan biogeographical area that is rich and unique in biological diversity. Sacred groves range in size from a few trees to dense forests of hundreds of hectares. Arpa River is the lifeline of Bilaspur and has many check dams on it that help in boosting the vegetation in area. The present study reports that the forest cover is mainly occupied by Sal (Shorea robusta), Teak (Tectona grandis), Bamboo (Dendrocalamus strictus), Muhua (Mudhuca indica), Shisham (Dalbergia sissoo), Semal (Bombax ceiba), Tendu (Diospyros melanoxylon), Imli (Emblica officianalis) and Babul (Acacia catechu) etc tree species. The major area is under Sal (40.56%) and Teak (9.42%) of the total forest area while rest of forest cover (50.02%) showed mixed population of different species. The entire forest cover has broadly classified as very dense, dense and open forest having coverage of 2256, 36472 and 17135 sq. Km, respectively. In these groves, different forms of vegetation in these forests including shrubs and climbers. Grazing and hunting are prohibited and only the removal of dead wood is allowed. Sacred groves reflect what ecologist's call social fencing. Sociologists say that in the absence of written laws, religion played an important role in enforcing social norms and codes to protect aforementioned forest in Arpa River watershed. [ABSTRACT FROM AUTHOR]

Mosquito control with the use of insecticides is faced with the challenges of insecticide resistance in disease vectors, community refusal, their high cost, operational difficulties, and environmental concern. In view of this, integrated vector control strategies with the use of larvivorous fishes such as Guppy (Poecilia reticulata) and Gambusia (G. affinis) as biological control agents were used in controlling mosquito breeding in different types of breeding places such as intradomestic containers, various types of wells, rice-fields, pools, ponds and elsewhere in malaria prone rural areas of central Gujarat. Attempts were also made to demonstrate composite fish culture in unused abandoned village ponds by culturing Guppy along with the food fishes such as Rohu (Labeo rohita), Catla (Catla catla) and Mrigal (Cirrhinus mrigala). Income generated from these ponds through sale of fishes was utilized for mosquito control and village development. The technology was later adopted by the villagers themselves and food fish culture was practised in 23 ponds which generated an income of Rs 1,02,50,992 between 1985 and 2008. The number of villages increased from 13 to 23 in 2008 and there was also gradual increase of income from Rs 3,66,245 in 1985-90 to Rs 55,06,127 in 2002-08 block. It is concluded that larvivorous fishes can be useful tool in controlling mosquito breeding in certain situations and their use along with composite fish culture may also generate income to make the programme self-sustainable.

Anopheles annularis is widely distributed mosquito species all over the country. An. annularis has been incriminated as a malaria vector in India, Sri Lanka, Bangladesh, Myanmar, Indonesia, Malaysia and China. In India, it has been reported to play an important role in malaria transmission as a secondary vector in certain parts of Assam, West Bengal and U.P. In Odisha and some neighbouring countries such as Sri Lanka, Nepal and Myanmar it has been recognised as a primary vector of malaria. This is a species complex of two sibling species A and B but the role of these sibling species in malaria transmission is not clearly known. An. annularis is resistant to DDT and dieldrin/HCH and susceptible to malathion and synthetic pyrethorides in most of the parts of India. In view of rapid change in ecological conditions, further studies are required on the bionomics of An. annularis and its role in malaria transmission in other parts of the country. Considering the importance of An. annularis as a malaria vector, the bionomics and its role in malaria transmission has been reviewed in this paper. In this communication, an attempt has been made to review its bionomics and its role as malaria vector. An. annularis is a competent vector of malaria, thus, due attention should be paid for its control under the vector control programmes specially in border states where it is playing a primary role in malaria transmission.

Background & Objectives: Certain indigenous fish can play potential role in vector control. The study recorded distribution of Aphanius dispar (Rüppell) in its native habitats in Gujarat, India and evaluated its larval propensity for Indian mosquito vectors., Methods: Fishes were surveyed in various districts of Gujarat and samples were collected from coastal habitats and were identified to species. Physicochemical properties of water samples were analysed in the laboratory. Five laboratory acclimatized adult fish (2.2-3 cm) released in chlorine - free water in glass jars were provided with 500 larvae daily. Five replicates were run. Daily consumption of I to IV instars of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus was recorded separately for three days. Anopheles stephensi larval control using the fish in industrial tanks (9-180 m2 ) was evaluated., Results & Conclusion: The fish was found in large numbers in estuarine waters, rivulets, backwaters and small dams in the districts of Kutch, Jamnagar, Patan and Anand in Gujarat. Mean daily consumption of larvae in laboratory was as follows: An. stephensi 128 ± 0.2 to 204 ± 6; Cx. quinquefasciatus 24 ± 4 to 58 ± 10; Ae. aegypti 43 ± 5 to 68 ± 2. In water tanks, A. dispar reduced 93% larval counts by Day 7 and 98% by Day 21 (p <0.01), showing high larval propensity. A consolidated information on bionomics, tolerance and physicochemical properties of water taken from natural habitats of A. dispar indicate its high larvivorous potential. Large - scale evaluation is warranted to evaluate its potential in vector - borne disease control.

Background & Objectives: Two bacterial larvicide (bio-larvicide) formulations--Bacticide and VectoBac containing viable endospores and delta endotoxin of Bacillus thuringiensis var israelensis H-14 were evaluated in 2001 for their mosquito larvicidal efficacy under the operational conditions of urban malaria control programme in Surat city, India., Methods: Larvicides were applied at the recommended dose in selected breeding habitats of Anopheles (An. stephensi), Aedes (Ae. aegypti) and Culex (Cx. quinquefasciatus) and reductions in the densities of III and IV instars were compared with that of untreated matched controls., Results: At the construction sites in cemented tanks/chambers VectoBac produced reduction in the density of III and IV instar larvae of An. stephensi (98-100%) and Ae. aegypti (100%) in the first week of application whereas Bacticide produced 71-100% reduction in An. stephensi and 100% in Ae. aegypti. Re-application of VectoBac on Day 10 caused better control up to Day 20 when compared with Bacticide. In stagnant water pools, VectoBac produced 27.6-85.3% reduction in the larvae of An. subpictus and 18.5-83.8% in those of Cx. quinquefasciatus whereas Bacticide produced 23.3-30.3% and 39-97.2% reduction in An. subpictus and Cx. quinquefasciatus larval densities in the first week post application, respectively. Bacticide application gave better impact on Cx. quinquefasciatus larvae in the second week after re-application as compared to VectoBac. In storm water drains, VectoBac caused respectively 6.2-100% and 6.4-97.6% reduction in An. subpictus and Cx. quinquefasciatus larvae in the first week of application whereas Bacticide produced 100% and 13.3-98.8% reduction in An. subpictus and Cx. quinquefasciatus larval densities, respectively., Interpretation & Conclusion: Both the formulations were equally effective on An. subpictus and Cx. quinquefasciatus larvae after a second application. The results showed that application of these biolarvicides would be required at 7-10 day intervals. The health workers engaged in the application of biolarvicides reported a better ease of handling and application of the liquid formulation (VectoBac) than the wettable powder formulation (Bacticide).

Studies on mosquito breeding and its control through Gambusia affinis in nursery and paddy fields after transplantation of seedlings were carried out during June to October 1991 in about 10 ha rice field area. Six anopheline species, viz. An. culicifacies, An. annularis, An. subpictus, An. nigerrimus, An. barbirostris and An. aconitus, and four culicine species, viz. Cx. tritaeniorhynchus, Cx. bitaeniorhynchus, Cx. quinquefasciatus, and Aedes sp. could be identified. These were found breeding in rice fields with fluctuations in their percentage composition, exhibiting species succession in different months. G. affinis survived well in submerged rice fields and provided 87.8% mosquito larval control. In rice fields which exhibited intermittent drying up leading to formation of pools, puddles etc., moderate larval control was achieved. However, in nursery rice fields, this method was not applicable. Mosquito larval control through larvivorous fish in rice fields can be achieved but the method has limitations.

A survey of fishes in Shahjahanpur in different aquatic habitats revealed 35 indigenous fish species. Out of 35 fish species, 24 were found feeding on mosquito larvae of which 6 species, viz. Chela bacaila, Puntius stigma, Rasbora daniconius, Esomus danricus, Colisa fasciatus and Danio sp., had good larvivorous potential. Most of the fish species preferred to feed on III and IV instar larvae. In the presence of planktonic food, the consumption capacity of fishes for mosquito larvae was lesser on third day (D3) of observation than on first day (D1). The difference in the consumption of mosquito larvae between D1 and D3 was significant (P < 0.01). Similarly, difference in the feeding capacity of fishes in the months of September and January was highly significant (P < 0.001). But there was no seasonal variation in the preference of instar-wise consumption. Indigenous fish species such as C. fasciatus, E. danricus, P. stigma, R. daniconius and Danio sp. could therefore play a significant role in controlling mosquito breeding in this area.

In villages of District Shahjahanpur, 122 decentralized Gambusia multiplication ponds were established to cover the need of the entire district. Profuse breeding of Gambusia was observed in these ponds. The fishes are being successfully used in mosquito control all over the district. In July 1990 there was a widespread flood due to which 70 Gambusia multiplication ponds were affected and the fish was washed away in large numbers, leaving only a scanty population in the flood-affected ponds. We utilized this opportunity to study the natural dispersal and colonization of Gambusia in different aquatic habitats. The study revealed that Gambusia was either not found in most habitats or was present in very small numbers, and on its own Gambusia was unable to eliminate the local fauna to become a dominant species. Predatory fishes and birds played a major role in eliminating Gambusia. Gambusia is therefore unlikely to pose any ecological hazard in vector-control programmes.

Culture of Gambusia affinis along with carps in fish culture practice in village ponds in Shahjahanpur distt., U.P., has revealed very little difference in fish productivity (1539 kg/ha in ponds with Gambusia, 1572 kg/ha in ponds without Gambusia). The growth and survival of Gambusia were found to be good in most of the composite fish culture ponds. Culture of Gambusia along with edible fish in village ponds is, therefore, recommended to get the dual benefit of fish production and control of mosquito proliferation in village ponds.