Journal of Environment and Sociobiology

P. Haldar ¹

Affiliations
1 Department of Zoology, Visva Bharati University, Santiniketan-731 235, West Bengal, IN

Abstract

This paper deals with an unusual behaviour of some fshes, prawns and shrimps reared in a nano pond of 26' × 18' size, located in the homestead area at Santiniketan, Birbhum district, West Bengal. Water source of this mini-size pond was rain water and also from deep tube-well or well water during dry seasons. After rain fall water of this pond becomes turbid due to erosion of soil from the bank. Once a papaya plant of 6 months of age, having girth of 3" at base and 2" at the top and a length of 4' was cut into three pieces and was put in water of the pond during a sunny day at about 9 AM in the month of July 2012 to clear the turbidity of water. After 24 hrs, it was found that the water became clean and transparent. After 48 hrs at about 8 AM, the crustacean species, mainly the galda prawns were found to try to keep their head portion above the water at the edge of the pond, while most of the small shrimp species came near the bank and died after 3-4 hours. By this time the carp varieties of fishes appeared sluggish in nature whereas the Tilapia and the Nilentika showed normal behaviour. Thus, it seems that the papaya plant and/or its latex, containing papain can be utilized in limited doses to catch the prawn and shrimp species in an eco-friendly way, minimising the cost of catching without detriment to the health of shrimp-eaters.

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Hena Anand ¹, Sarasi Das ¹, Arijit Ganguly ¹, P. Haldar ¹

Affiliations
1 Department of Zoology, Visva-Bharati University, Santiniketan-731235, West Bengal, IN

Abstract

Experiments were done to estimate biomass production by mass rearing of Oxya fuscovittata (Marschall) and Spathosternum prasiniferum prasiniferum (Walker) under laboratory condition, in order to utilize them as non conventional protein rich animal feed supplement. For this purpose fecundity, fertility, adult emergence, sex-ratio, fresh and dry body weight, protein and energy content in acridid tissue were determined. This study has shown that taking a single pair of male and female as starting point, O. fuscovittata may produce 225.07 kg dry biomass/year by mass rearing. Thus O. fuscovittata with high protein content and ability to produce high biomass can be utilized in animal feed as protein supplement through establishment of acridid farms.

Keywords

Oxya fuscovittata, Fecundity, Energy Content, Protein Content, Acridid Farming.

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P. Haldar ¹, Hena Anand ¹

Affiliations
1 Department of Zoology, Visva-Bharati University, Santiniicetan-731 235, IN

Abstract

The knowledge of the life span and sex ratio is of immense importance for biomass production of acridids which can be utilized as non-conventional nutrient source in animal feed. Life span and sex ratio were studied on four Indian acridid species, i.e., Oxya fuscovittata, Acrida exaltata, Hieroglyphus banian and Spathosternum prasiniferum prasiniferum under laboratory based rearing. The study reveals that H. banian required more rearing time than A. exaltaia, 0. fuscovittata and S. pr. prasiniferum. In each species females were found to live longer than the males. The sex ratio study shows female dominance in O. fuscovittata and A. exaltata and male dominance in H. banian and S. pr. prasiniferum under laboratory condition.

Keywords

Acridid, Life Span, Sex Ratio, Biomass, Rearing.

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Susanta Nath ¹, P. Haldar ²

Affiliations
1 Department of Zoology, Darjeeling Govt. College, Darjeeling-734 101, IN
2 Department of Zoology, Visva Bharati University, Santiniketan-731235, IN

Abstract

The present communication deals with the effect of heavy metals pollution on the population fluctuation of an acridid, Oedaleus abrnptus. The amount of lead, cadmium and copper crossed the recommended limit and tolerance limit in the industrial area. The study showed that toxic metal pollution has a significant role in population fluctuation of Oedaleiis abruptiis

Keywords

Acridid, Pollution, Metal.

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Hiroj Kr. Saha ¹, Hena Anand ¹, P. Haldar ¹

Affiliations
1 Department of Zoology, Visva-Bharati University, Santiniketan- 731235, West Bengal, IN

Abstract

Acridids are one of the most dominant phytophagus insects which play an important role in the functioning of forest ecosystem. Seasonal occurrence and fluctuation and. sex ratio are important components of population structure in acridid community. The investigation on seasonal occurrence and sex ratio on three species of acridid, viz.. Ditiopiernis venusta (Walker), Oedaleus abruptus (Thunberg), and Truxalis indica (Bol.) in dry deciduous forest of West Bengal revealed that D. venusta was the most dominant species in the study area. The population of acridids fluctuates in different season and highest number was observed during autumn. Statistical analysis reflects that male and female ratio are more or less equal.

Keywords

Acridids, Seasonal Occurrence, Sex Ratio.

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