Distance Sampling

Grasslands are one of the tropics' most critically threatened habitats, while conservation attempts are rarely concentrated at these ecologically important landscapes. Sambar deer is a large wild ruminant found throughout Sri Lanka, in both grassland and forest ecosystems. Amidst their key position in the trophic web in 'wet patana' grasslands of the Horton Plains National Park (HPNP), Sri Lanka, population of sambar deer has not been estimated during recent decades. In this research, field surveys were performed in the total grasssland area of 9.4 km 2 in HPNP to estimate the density of Sambar deer, for a period of six months, from 1 st of January to 31 st of June 2018. Sambar deer were sampled along line transects from 1600 hrs-1830 hrs for up to 300m of maximum distance from the line and the distance sampling technique was used to solve imperfect detection for the first time. Counting was carried out for three days per month along a 6.71 km road transect through grasslands. Collected data on sambar deer observations along the transect was analyzed by using the DISTANCE 7.2 computer application. The highest sambar deer density in HPNP was estimated as 113.45 ±11.79 individuals/km 2 with a detection probability of 28% in January with an estimated absolute abundance of 1066 ± 110.82 individuals. Our findings indicate consequences of imperfect detection of a statistically strong model. Sambar deer density estimates from this research lays the context for regular surveillance of their population , examining the effects of habitat alterations and assessing the long-term viability of 'wet patana' grassland in HPNP, offering insight on the conservation of the fragile habitat of the resident sambar deer population.

Large continuous rainforests are the main hope for sustaining the population of large-bodied vertebrates that cannot cope with fragmentation or unsustainable hunting. The Brazilian Atlantic forest is considered a biodiversity hotspot and although highly fragmented, it still contains large forest patches that may be important for the conservation of mammals that require large areas. Here, we estimated species richness, density and biomass of medium-and large-sized mammals along the largest remnant of the Atlantic rainforest, Brazil (the Serra do Mar bioregion), an estimated area of 8000 km 2. We recorded 44 species based on 4090 km of diurnal line transects and camera traps, animal tracks and interviews in 11 continental regions and two large land-bridge islands. We found high levels of similarity in mammalian composition between pairs of sites in the continental forest sites (0.84– 1), but much lower similarity between pairs from the continental forest sites and the two large land-bridge islands (0.29–0.74) indicating potential local extinctions or poor dispersal of continental mammals to these islands. In addition, we found that the density and biomass varied 16-and 70-fold among sites, respectively. Mammalian biomass declined by up to 98% in intensively hunted sites and was 53-fold lower than in other Neotropical non-fragmented forests. Although this large forest remnant is able to maintain a high diversity of medium-and large-bodied mammal species, their low density and biomass may affect the long-term persistence of these populations and the ecosystem services they provide.

"""We studied a naturalized population of monk parakeet breeding in an urban park in Rome, by collecting data on the diurnal and feeding activity, space use (eg, roosting preferences, flight height) and behavioural traits (eg, cluster size).  Consideration on the potential ecological impact of the species is also made.  The diurnal activity of parakeets did not differ between morning and afternoon.  Most individuals were observed in flight 6-10 m from the ground, and when at roost, parakeets preferred perch es higher than 5 m.  The clusters sighted on ground were significantly larger in size than those observed on roosts, while cluster size was not linked to flight height.  For this species, the observed roost preference indicates that the availability of perches on high trees seems to be an important factor for habitat selection: standing on trees may increase the chances to identify trophic resources, reduce the risk of predation when at rest, and prevent
overheating from high summer temperatures during the day.  Regarding to feeding habits, at our study site the monk parakeet fed on different plant species both on the trees and at the ground level (eg, Fabaceae, Ulmaceae, Poaceae, Rosaceae), showing a clear preference towards some plant species, irrespective to their abundance, and with Scolymus hispanicus (Asteraceae) as the most exploited species by far."""