prasanta saikia | Gauhati University (original) (raw)

Uploads

Papers by prasanta saikia

Northeast India has been recognised as the hotspot of Chelonian diversity within Indian subcontin... more Northeast India has been recognised as the hotspot of Chelonian diversity within Indian subcontinent. The region harboars above 22 species and subspecies of Chelonian fauna belongs to three families viz., Bataguridae (Emydidae), Trionychidae and Testudinidae. Several workers have studied Chelonian species in Assam and as well as in Northeast India since last two decades. However, the detailed investigation and reporting of Chelonian diversity in Orang National Park has not been done by any workers since the present works. The present study has been carried out from 2009 through 2012 to investigate the total diversity of Chelonian species and its distribution patterns in various seasons of the year and as well as its threat factors. Study revealed the existence of 12 Chelonian species under Bataguridae, Testudinidae and Trionychidae families. The presence of Brahmaputra River and Panchnoi Sand-bars has created suitable habitats for chelonian breeding. However, the local people have regularly been using small mesh sized fishing nets during winter and pre-monsoon season that catches and drown aquatic chelonians. Further, annual grass burning practices of the park authority likely to have major impact on the population declines of chelonian species in the study area. The present study highlighted the diversity and abundance of Chelonian species and its conservation threats in Orang National Park.

Deepor Beel is one of the largest and most important riverine wetland in the Brahmaputra Valley o... more Deepor Beel is one of the largest and most important riverine wetland in the Brahmaputra Valley of lower Assam, India and is representative of the wetlands found within the Burma Monsoon Forest biogeographic region. Altogether 232 bird species belonging to 42 families were recorded during a sixty months survey in Deepor Beel. Of all the species recorded, 137 were resident and 97 were migratory. About 4.1 km 2 of the wetland was declared as a wildlife sanctuary in 1989 and larger area (40 km 2) as a Ramsar wetland of international importance in November, 2002. Further it has been identified as an Important Bird Area (IBA) by BNHS and Birdlife International since 2003. There are fourteen villages (1200 families) around Deepor Beel wetland, most of which belong to low income groups living under the poverty line and depend directly or indirectly on the wetland's natural resources. Present field investigation has recognized that, at least above 500 families of poor scheduled cast people in an around Deepor beel Ramsar site have entirely depends their livelihood on fishing and other herbaceous plant resources collection at Deepor beel Ramsar site and sell them at nearby daily markets. Currently, the wetland and its biota are facing a numerous threats in the form of encroachments, civil construction, garbage dumping, rail road development, unregulated fishing practices and rice cultivation and most importantly the lack of a single authority with mandate to manage the wetland. Conservation of this wetland has been proposed keeping in view the needs for bird populations and local villagers. Involvement of local communities in the conservation measures is emphasized. The wetland with additional terrestrial forest land should be conserved as Deepor beel Environmental Park with adequate legislative and administrative provisions and certain usages right to the indigenous people.

Open bill stork characterized by having large bills, with a gap of mandibles in middle. The prese... more Open bill stork characterized by having large bills, with a gap of mandibles in middle. The present article mainly emphasized the feeding ecology of the open bill storks, emphasized on feeding behaviour, techniques and strategies of feeding and types and availability of prey species in the Brahmaputra Valley, Assam. Wetlands (Beels) of Brahmaputra river system and harvested Paddy fields were the favourite foraging sites for open bill storks in non breeding seasons. It has been observed that during non breeding season open bill stork devoted maximum time in resting (35% of the active period) either on a high land or on roosting tree. 33% of the active time was utilized in search of food. Soaring was one of the important behaviour noticed in open bill stork. An open bill stork utilized 13% of the day active time in soaring behavior. Minimum time was used in aggression behaviour that includes chasing, threatening, snatching etc. Open bill storks feed molluscs and fishes and the types of prey never vary during summer and winter. The most preferred prey was Pila globosa. The Open bill stork was a flock feeder, both during breeding and non-breeding season, but occational1y single bird was also found to forage in the habitat. While foraging, they did not maintained any inter individual spacing. When a stork capture a Pila. it picks up the prey through the bill either at tip of bill or at middle of bill then it went away from the other individuals as others individuals try to snatch it. The stork positioned in a suitable place and the shell was rolled up and down within the beak in several times to broken down the operculum of the mollusc.

The genus Chrysilla (Salticidae) was first described by Thorell (1887) and is insufficiently know... more The genus Chrysilla (Salticidae) was first described by Thorell (1887) and is insufficiently known. Presently eight species has been reported. Three of them were known only from their males, four from females and only one from both male and females. The type species (Chrysilla lauta), C. albens, C. delicata, C. doriai, C. deelemani and C. acerosa belongs to Asia. This is the first record of genus Chrysilla from India. The specimen was collected from sugarcane field of Sonitpur district of Assam, India. The type specimen was deposited in the Biodiversity Museum, Department of Zoology and Animal Ecology and Wildlife Biology lab, Gauhati University, India. The genus Chrysilla can be distinguished from Phintella and Leius by the thin , long and more colourfull bodies, stronger RTA and much longer than wide genital bulb of male palps, copulatory openings separated by one diameter or so and piriform spermathecae of epigyne. The new species is similar to that Chrysilla lauta, Chrysilla deelemani and Chrysilla acerosa but differs from the former two by the wider than long RTA with a ventral tip and the much longer embolus as in Chrysilla acerosa Wang and Zhang, 2012, differ from the later by the shape of prosoma, hight of clypeus, bulbus and median apophysis. .

Northeast India has been recognised as the hotspot of Chelonian diversity within Indian subcontin... more Northeast India has been recognised as the hotspot of Chelonian diversity within Indian subcontinent. The region harboars above 22 species and subspecies of Chelonian fauna belongs to three families viz., Bataguridae (Emydidae), Trionychidae and Testudinidae. Several workers have studied Chelonian species in Assam and as well as in Northeast India since last two decades. However, the detailed investigation and reporting of Chelonian diversity in Orang National Park has not been done by any workers since the present works. The present study has been carried out from 2009 through 2012 to investigate the total diversity of Chelonian species and its distribution patterns in various seasons of the year and as well as its threat factors. Study revealed the existence of 12 Chelonian species under Bataguridae, Testudinidae and Trionychidae families. The presence of Brahmaputra River and Panchnoi Sand-bars has created suitable habitats for chelonian breeding. However, the local people have regularly been using small mesh sized fishing nets during winter and pre-monsoon season that catches and drown aquatic chelonians. Further, annual grass burning practices of the park authority likely to have major impact on the population declines of chelonian species in the study area. The present study highlighted the diversity and abundance of Chelonian species and its conservation threats in Orang National Park.

Deepor Beel is one of the largest and most important riverine wetland in the Brahmaputra Valley o... more Deepor Beel is one of the largest and most important riverine wetland in the Brahmaputra Valley of lower Assam, India and is representative of the wetlands found within the Burma Monsoon Forest biogeographic region. Altogether 232 bird species belonging to 42 families were recorded during a sixty months survey in Deepor Beel. Of all the species recorded, 137 were resident and 97 were migratory. About 4.1 km 2 of the wetland was declared as a wildlife sanctuary in 1989 and larger area (40 km 2) as a Ramsar wetland of international importance in November, 2002. Further it has been identified as an Important Bird Area (IBA) by BNHS and Birdlife International since 2003. There are fourteen villages (1200 families) around Deepor Beel wetland, most of which belong to low income groups living under the poverty line and depend directly or indirectly on the wetland's natural resources. Present field investigation has recognized that, at least above 500 families of poor scheduled cast people in an around Deepor beel Ramsar site have entirely depends their livelihood on fishing and other herbaceous plant resources collection at Deepor beel Ramsar site and sell them at nearby daily markets. Currently, the wetland and its biota are facing a numerous threats in the form of encroachments, civil construction, garbage dumping, rail road development, unregulated fishing practices and rice cultivation and most importantly the lack of a single authority with mandate to manage the wetland. Conservation of this wetland has been proposed keeping in view the needs for bird populations and local villagers. Involvement of local communities in the conservation measures is emphasized. The wetland with additional terrestrial forest land should be conserved as Deepor beel Environmental Park with adequate legislative and administrative provisions and certain usages right to the indigenous people.

Open bill stork characterized by having large bills, with a gap of mandibles in middle. The prese... more Open bill stork characterized by having large bills, with a gap of mandibles in middle. The present article mainly emphasized the feeding ecology of the open bill storks, emphasized on feeding behaviour, techniques and strategies of feeding and types and availability of prey species in the Brahmaputra Valley, Assam. Wetlands (Beels) of Brahmaputra river system and harvested Paddy fields were the favourite foraging sites for open bill storks in non breeding seasons. It has been observed that during non breeding season open bill stork devoted maximum time in resting (35% of the active period) either on a high land or on roosting tree. 33% of the active time was utilized in search of food. Soaring was one of the important behaviour noticed in open bill stork. An open bill stork utilized 13% of the day active time in soaring behavior. Minimum time was used in aggression behaviour that includes chasing, threatening, snatching etc. Open bill storks feed molluscs and fishes and the types of prey never vary during summer and winter. The most preferred prey was Pila globosa. The Open bill stork was a flock feeder, both during breeding and non-breeding season, but occational1y single bird was also found to forage in the habitat. While foraging, they did not maintained any inter individual spacing. When a stork capture a Pila. it picks up the prey through the bill either at tip of bill or at middle of bill then it went away from the other individuals as others individuals try to snatch it. The stork positioned in a suitable place and the shell was rolled up and down within the beak in several times to broken down the operculum of the mollusc.

The genus Chrysilla (Salticidae) was first described by Thorell (1887) and is insufficiently know... more The genus Chrysilla (Salticidae) was first described by Thorell (1887) and is insufficiently known. Presently eight species has been reported. Three of them were known only from their males, four from females and only one from both male and females. The type species (Chrysilla lauta), C. albens, C. delicata, C. doriai, C. deelemani and C. acerosa belongs to Asia. This is the first record of genus Chrysilla from India. The specimen was collected from sugarcane field of Sonitpur district of Assam, India. The type specimen was deposited in the Biodiversity Museum, Department of Zoology and Animal Ecology and Wildlife Biology lab, Gauhati University, India. The genus Chrysilla can be distinguished from Phintella and Leius by the thin , long and more colourfull bodies, stronger RTA and much longer than wide genital bulb of male palps, copulatory openings separated by one diameter or so and piriform spermathecae of epigyne. The new species is similar to that Chrysilla lauta, Chrysilla deelemani and Chrysilla acerosa but differs from the former two by the wider than long RTA with a ventral tip and the much longer embolus as in Chrysilla acerosa Wang and Zhang, 2012, differ from the later by the shape of prosoma, hight of clypeus, bulbus and median apophysis. .