Population distribution and habitat analysis of Rufous treepie (Dendrocitta vagabunda) in Abbottabad, Pakistan

Abstract The Rufous treepie (Dendrocitta vagabunda) belongs to family corvidae, order Passeriformes which includes about 100 species. The current study was conducted to gather information about the Population distribution and habitat analysis of D. vagabunda at District Abbottabad, Pakistan. The data were collected on monthly basis both morning and evening times (2018-2019). “The ‘’Point count Method” was used for population estimation and ‘’Quadrates Method” for habitat analysis of study area. The result shows an average month-wise population density of D. vagabunda was maximum at Jhangra 0.14±0.039/ha, whereas minimum at Havelian 0.11±0.022/ha. There was no significant difference (p>0.05) among monthly population densities of D. vagabunda, however, a significant difference (p<0.05) was found between morning and evening times population of the specie. The present study revealed that importance value index (IVI) of plants species at Sherwan, Bakot, Havelian, Langra and Jhangra were 59.6±12.6, 50.1±6.9, 53.4±6.3, 66.8±10 and 60.1±7.7. Likewise, the frequency of shrubs at Sherwan, Bakot, Havelian, Langra and Jhangra were 33.3±4.2, 45±9.4, 46.7±8.2, 55.6±22.2 and 37.5±8.5. Similarly, the frequency of herbs at Sherwan, Bakot, Havelian, Langra and Jhangra were 40.4±6.0, 37.5±5.6, 53.3±7.4, 48.5±5.2 and 46.9±7.4 respectively. Our results show the study area as suitable habitat for D. vagabunda.


Study area
The present study was conducted in District Abbottabad, positioned at an altitude of 1,225 meter, lies between 33° 50' and 34° 23' North latitude and 73° 35' and 73° 31' East longitude ( Figure 1) with 1,967 km 2 area (Ali et al., 2017). Most of the area of District is comprised of mountainous topography and the average elevation of mountains ranges from 2500m to 2700m (IUCN Pakistan, 2004;Ullah et al., 2020). The aim of study was to determine the population density, distribution and habitat preference of D. vagabunda including Sherwan and Bakot (hilly areas), Havelian, Jhangra and Langra (plane areas) with the total area of 6942 hectares.

Population estimation
Field surveys were conducted (2018)(2019). The "Point Count Method" was used in hilly area (Sherwan and Bakot) and plane area (Havelian, Langra and Jhangra). Preliminary surveys were conducted to allow covering a wider range of the potential habitats of D. vagabunda. In point count method "Vantage points" were selected of fixed radius (50 m 2 ) and duration of time (15 minutes) for population estimation both at morning and evening time (Rolando et al., 2007).
Density and abundance are the essential ecological information required for population ecology and scope of ecology covers distribution of organism and its abundance (Buckland et al., 2001;Stephens et al., 2019). D. vagabunda is fairly wide spreads throughout Indus plains and foot hills up to 2300m and prefers tree or bush cover and occupies altitudinal range of 1450-1700m in Bhowali, while its altitudinal range lies between 350-500m in Haldwani along with its status is recorded as residential species in Nainital district under conservation status of Indian wildlife protection Act (Grimmett et al., 2008;Joshi et al., 2012).
The D. vagabunda is arboreal bird of the teak forests, but seems at homes, in open scrub jungle, gardens, cultivated trees and scrub forest areas, not in desert without trees and prefers shrubby habitat (Sidhu et al., 2010;Mirza and Wasiq, 2012). The D. vagabunda occupied in whole of sub-tropical forest and tropical evergreen forest, and found abundant in all habitats, as a residential and winter visitor spp in Muzaffrabad city in Azad Jammu and Kashmir in Pakistan, also found in coniferous forest, mixed deciduous

Estimation of population density
Population density estimation was carried through sighting observations to assess the accuracy of perpendicular measurement by Visual Encounter Method (VEM) (Ralph et al., 1995). Data recording was done by thoroughly surveys on monthly basis for the whole study period. The measurements were recorded on flushing the bird (Buckland et al., 2008).
Population density of D. vagabunda is represented by Formula 1.

Total population No of D vagabunda in all sites
Total area of study sites = × (2)

Habitat analysis
In order to analyze the preferred habitat used by D. vagabunda, all major plant species were collected, identified and preserved in the form of herbarium sheets. Vegetation sampling was carried out by using "Quadrates Method" as described by (Sigdel, 2008). Among the vegetation, trees were examined by using quadrates of (10 × 10m), shrubs (5 × 5m) and herbs (1 × 1m) (Ali et al., 2018).

Vegetation analysis
The collected data were used to calculate species richness, density, relative density, frequency and relative frequency of trees, shrubs and herbs in the study area by using the following Formulas 3 to 7.

IVI
Relative density Relative frequency Relative dominance

Statistical analysis
Analysis of Variance (ANOVA) was applied for analysis of data regarding in different habitats for month-wise population densities of D. vagabunda. Student's paired "t-test" was applied for comparison between morning and evening time's population densities.

Month-wise population estimation
Month-wise population density of D. vagabunda was estimated at five sites of the study area. Average month-wise population density of the D. vagabunda was maximum in Jhangra (0.14±0.039/ha) while minimum in Havelian (0.11±0.022/ha) (Table 1) (Figure 2).

Fluctuation of D. vagabunda population
The morning and evening population density of D. vagabunda was considerably higher during morning as compared to that in evening time and this trend was consistently observed during the entire study period. Population density of D. vagabunda during morning was greater 0.038±0.0039/ha, than that of evening time (0.032±0.0019/ha) in Sherwan. Similarly, its population density was maximum (0.031±0.0032/ha), at morning and minimum (0.028±0.0032/ha) at evening time in Bakot. The population density at morning and evening was 0.037±0.0042/ha and 0.036±0.0025/ha, in Havelian respectively. In Langra, the maximum population density was 0.042±0.0047/ha, at morning and higher 0.033±0.0054/ha, at evening time ( Figure 3). The population density was found 0.037±0.0038/ha, during morning and (0.035±0.0026/ha) at evening in Jhangra (Table 2) ( Figure 4).

Habitat analysis
The presence of abundant trees, shrubs and herbs are essential for the survival of D. vagabunda at any area. The importance value index for trees, frequencies of shrubs and herbs indicates the relative population of D. vagabunda might survive in this area.
The major tree species for D. vagabunda at Sherwan site having dominant IVI 95.14 of Zanthoxylum armatum with co-dominant IVI 126.85 was recorded for Grewia optiva, whereas minimum IVI was observed for Melia azedarach and Morus alba 31.68. Similarly, the frequency of shrubs 33.3±4.2 and herbs was 40.4±6.0 (Table 3, 4 and 5).
At Bakot, the dominant tree species having IVI 62.77 of Ailanthus altissima with co-dominant IVI was recorded for Acacia modesta 93.87, and minimum IVI was observed for Melia azedarach 31.26. Therefore the frequency of shrubs and herbs at this site was 45±9.4 and 37.5±5.6 respectively (

Discussion
The previous published literature shows that D. vagabunda is commonly found abundant in vegetation in sub-tropical forest and scrub areas in India as mentioned by Thakur et al. (2010), whereas Jayson and Mathew (2000) reported its abundance found in tropical evergreen forest in Kerala. Moreover, Mirza and Wasiq (2012) revealed habitat utilization of D. vagabunda in cultivated trees and scrub forest areas, not in desert without trees.
The present study investigated the population density of D. vagabunda from October 2018 to June 2019 at five study sites of the district Abbottabad. Our study agrees with Bashir et al. (2012), who reported the estimated population density of D. vagabunda (0.045±0.015) during bank searches of avian species in upper Ganges in India. Moreover, Palita et al. (2011)  Similar results were reported earlier on by Saikia et al. (2014) for D. vagabunda 0.57 in dry season and 0.43 in wet season in North-East India, because the area is large as compared to our study area. However, Awan et al. (2009) also reported relative abundance of 0.010 D. vagabunda in Azad Jammu and Kashmir, Pakistan. Chatterjee et al. (2014) reported density of D. vagabunda in Grasslands (0.00/ha), Swamp forests (0.00/ha), Riverine forests (1.04/ha), Miscellaneous plantations (1.56/ha), Forest edges (2.60/ha) and Wetlands (0.00/ha) in west Bengal India, because the area is large as compared to our study area. Whereas, Roy et al. (2012) reported the estimated population density of D. vagabunda in Gorumara National Park (4.9/ha), in Buxa Tiger Reserve (0.0/ha), and in Rasik Beel Wetland Complex (3.9/ha) in three different regions of North Bengal in India, because the area is too large as compared to our study area.
The present study is supported by Trivedi (2006), who reported the population density of D. vagabunda (1.93±0.86) in Gujarat in India. Similar results to the present study were obtained by Sidhu et al. (2010), where they also described average relative abundance of D. vagabunda in Forest (1.00), in Buffer (4.56) and in village (3.75) in Thattekad and in Forest (0.00), in Buffer (0.00) and in village (0.00) in Anamalai Hills in the Southern Western Ghats in India, because the area is large as compared to our study area.
No significant difference (p>0.05) was found among monthly D. vagabunda population densities/ha in hilly and plane areas through Analysis of Variance (ANOVA) ( Table 1). However, Statistical analysis (t-test) indicates a significant difference (p<0.05) among population densities/ha between morning and evening time population.

Conclusion
The results of current study explain the wide distribution of Rufous treepie in District Abbottabad. At all selected sites the specie was not affected by the human population