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Item Assessment of impacts of State highway 33 on flora and fauna of Nagarhole Tiger Reserve, India(Wildlife Institute of India, Dehradun, 2020) Habib, BilalAs part of the project funded by the National Tiger Conservation Authority, New Delhi, three sites were chosen for study- the Central Indian tiger landscape including major roads cutting across the animal corridors in the landscape, the National Highway 37 (now 715) cutting through the Kaziranga-Karbi Anglong landscape in Assam, and the State Highway 33 passing through the Nagarhole Tiger Reserve, Karnataka. At Nagarhole Tiger reserve, we intended to study the difference in the impacts of the SH 33 along its two stretches – one that is completely closed to traffic (decommissioned segment) and the other stretch that is closed for night time traffic (night traffic closed segment). We compared the floral (tree species composition and richness), and faunal (ungulate group size and composition, habitat use and activity patterns) characteristics along the two road stretches. We found that tree and sapling species richness was found to be higher in the decommissioned road segment as compared to the night traffic closed road segment, both of which comprised predominantly of native vegetation. On the other hand, shrubs and herbs had higher species richness in the night traffic closed road segment. We found higher species richness and cover of grasses, shrubs and herbs in the night traffic closed road segment, which can be attributed to the edge effect. Even though both the segments of the highway under study are homogenous in respect of rainfall regime, forest type and are managed as part of national park under the same management objectives (Gubbi et al. 2012), results of shrub and sapling study indicate that there exists some distinguishing factors along the two segments so as to favor different species. A further detailed study is required to point out the factors responsible. Contrary to the general understanding, invasive species cover for two of the common invasive species (Lantana camara and Eupatorium odoratum) was higher in the area devoid of traffic as compared to the night traffic closed road segment. This can be attributed to increased light intensity on the forest floor due to lower canopy cover in the decommissioned road segment and higher animal activity, who acts as seed dispersers. Lower canopy cover in decommissioned road segment can be the result of breakage of canopy and crushing of new regeneration by higher presence and more frequent activity of large mammals, like elephants. Mean group size of chital was found to be higher in the night traffic closed road segment, whereas mean crowding was higher in the decommissioned road segment. Higher presence of chital in the night traffic closed road segment can be because of availability of more fodder species and less risk of predation. In the decommissioned road segment, chital and wild pig’s habitat use is not affected by the distance from the state highway, whereas, sambar and elephant’s habitat choice is determined by distance from the highway. There has been a 16% increase in the traffic volume from 553 vehicles /day in the last 9 years as reported by Gubbi et al. (2012), to 659 ± 139.70 as reported in our study. However, though there has been an increase in the traffic volume, it is at a slower rate as compared to the increase from 2003 to 2010 level. The average speed of vehicles ranged from 27.5 MPH to 35.4 MPH. We found that in the night traffic closed road segment, animals have modified their activity periods to avoid the vehicular traffic. Most of the mammals are either active in the early morning hours before the road is opened for vehicular movement or late evenings after the road is closed. This suggests that there is a difference in activity pattern of these mammals along both the road segments, in order to understand which a further detailed study about behavior modification of mammals in relation to traffic and other road related disturbances needs to be carried out.Item Assessment of impacts of National Highway 715 (Earlier NH 37) on Wildlife passing through Kaziranga Tiger Reserve, Assam(Wildlife Institute of India, Dehradun, 2020) Habib, Bilal; Saxena, Akansha; Bhanupriya, R.; Jhala, Y.V.; Rajvanshi, A.As part of the project funded by the National Tiger Conservation Authority, New Delhi, three sites were chosen for study- the Central Indian tiger landscape including major roads cutting across the animal corridors in the landscape, the National Highway 37 (now 715) cutting through the Kaziranga-Karbi Anglong landscape in Assam, and the State Highway 33 passing through the Nagarhole Tiger Reserve, Karnataka. At Kaziranga National Park, we intended to quantify the characteristics of mortality of animals due to wildlife-vehicle collisions, and to assess the responses of wild ungulates to road-related disturbances in terms of changes in group size and composition, and habitat use patterns. Result shows that highways have adverse effects on the population of wildlife including endangered species of mammals and reptiles. Seasonal or monthly changes are the factors that influenced probability of roadkill numbers as it increased with the onset of summer and decreased towards winter. Annual monsoon floods in Kaziranga National Park from adjacent Brahmaputra River was found to be the main factor influencing large mammal mortality in wildlife-vehicle collisions. Apart from the direct impacts of roads on wildlife the indirect impacts like noise and disturbances associated with them impact significantly on the species that require an undisturbed or interior habitat. Similarly, present study exhibits variation in the group size composition of ungulates relative to distance from road. Group-size increased with respect to distance which indicates that anthropogenic effects of roads can lead to the habitat fragmentation of such species affecting population distribution. However, numbers and factors of wildlife-vehicle collisions may vary with site and conditionItem Status of wildlife between Kota barrage and Jawahar Sagar Dam, Rajasthan(Wildlife Institute of India, Dehradun, 2021) Johnson, J.A.; George, Arun; Sharma, Megha; Kavin, D.; Sreelekha Suresh; Gopi, G.V.; Hussain, S.A.The present study examined the impacts of post-construction phase of the cable-stayed bridge on the aquatic wildlife and river habitat quality of the Chambal River between Kota barrage and Jawahar Sagar dam, Rajasthan. The study was carried out between March and November 2021. The study area was divided into 5 segments (each comprising 5 Km length of river) and the segment 1 stats from the Kota barrage. We recorded good signs/ activities of smooth-coated otters in the study area. This species is listed under “Schedule II” of IWPA 1972 and "Vulnerable" as per the IUCN Red List. A total of 10 sites within five river segments were surveyed for otter signs during pre-monsoon and post-monsoon seasons. Out of which five sites (50%) have shown positive otter signs (fresh spraints, tracks, and direct sightings) during pre-monsoon, whereas in the post-monsoon season the number of otters occupied sites have reduced to four sites (40%). The otter occupancy map indicated, the segment 2 (just above the bridge area) had high level of otter presence. We recorded good population of bird diversity between Kota barrage and Jawahar sagar dam. A total of 132 bird species, which includes 45 wetland birds (N=1569), 21 species of raptors (N=928), and 66 species of other terrestrial birds (N=1351) were recorded. These include two Critically Endangered (Indian Vulture and Red-headed Vulture), one Endangered (Egyptian Vulture), one Vulnerable (Woolly-necked Stork) and four Near Threatened species (River Tern, Black-headed Ibis, Oriental Darter and Alexandrian parakeet). During the study period, the raptors, Indian Vulture (Gyps indicus) and Egyptian vultures (Neophron percnopterus) were very commonly recorded and more number of nests were recorded in the third segment of the study stretch. In addition to vulture nests, we also observed nests of Bonelli's eagle (Aquila fasciata) and Dusky eagle-owl (Bubo coromandus) in the riverside escarpments. We also recorded nests of three waterbird species, which include Grey Heron (Ardea cinerea), Black-crowned night heron (Nycticorax nycticorax) and Woolly necked stork (Ciconia episcopus). Avian richness was varying with the season maximum number of waterbirds were observed during pre-monsoon (S=40), this same trend was followed by raptors (S=15) and other terrestrial birds (S=57). The bird occupancy map indicated that the segment 1 and segment 2 supported high abundance birds. We also recorded two species of aquatic reptiles, which are Mugger (Crocodylus palustris) and Indian roofed turtle (Pangshura tecta). Though, the river banks are mostly of rocky and large boulders with limited sand beach, we found quite a few nesting sites of muggers along the river banks. A total of 34 individuals and 23 individuals of muggers were recorded during pre-monsoon and post-monsoon respectively. The study area also supports good population of freshwater fishes. Rapid Assessment Report - 6 - During the study we recorded 46 species of fishes from the study area. Fishes belonging to the carp family were dominant in species richness (S=22). Among the 46 species of fish, three species are listed under threatened categories as per the IUCN Red List. During the study period the important physicochemical parameters of the water was monitored and the values were significantly varied between the river segments (p<0.05). The pH was found to be slightly alkaline across the river segments ranged from 7.08±0.02 and 8.55±0.01. Like conductivity, total dissolved solids in water (TDS) varied, ranging from 91.54 ppm at the second segment of the river in postmonsoon to 150 ppm at the second segment in pre-monsoon. All water quality parameters were found within the normal range of river water quality. Based on our findings we conclude that the cable-stayed hanging bridge of Kota does not have any negative impact on the wildlife of the Chambal River. The bridge is on the stable rocky gorge area, around 30 m above the water level across the river Chambal without any supporting billers from the riverbed. Thus, there is no direct contact between the river and bridge structure. Further, the technology used in this structure is marvellous, because it is totally vibration and notice proof. In this study we had some significant observations very close to this cable bridge such as an active nest of Egyptian Vulture (Neophron percnopterus) very close to this bridge (25° 8'23.14"N, 75°47'36.64"E), which is just 80 meters away from the bridge and a nest of Woolly-necked Stork (Ciconia episcopus) just 200 meters downstream from the bridge (25° 8'20.90"N, 75°47'33.11"E). Generally, Woolly-necked Storks are assumed to prefer isolated areas for nesting (Mehta 2020). Previous studies indicated that disturbance is one of the major factors for avoiding nesting habitat by Storks (Bouton et al., 2005). We also observed the permanent roosting sites of the Indian eagle-owl (Bubo bengalensis) nearer to this bridge (25° 8'16.12"N, 75°47'27.02"E). Likewise, we observed number of direct sighting of otters and crocodiles near as well as downstream regions of bridge when compared to other segments of the rivers. Moreover, the water quality parameters examined were within the normal range of river water quality. Thus, the present study revealed that the presence of cable-stayed bridge does not have any negative impact on the aquatic wildlife and quality of habitats in the Chambal River.