Birds have very close association with trees. There is a complicated connection that is present between birds and trees. There are number of variables in a habitat such as vegetation cover, foliage height and these variables influence avian abundance and diversity. Birds need nests for incubation purposes, to raise young ones during breeding period, to hold eggs so nests act as a platform. Birds are near-ubiquitous, mobile, and approachable at fine progressive scales. Avian protection and management contains a considerate of bird-habitat associations. Birds vary a lot from one another in most of their existence configuration like habitation, nutrition, pigmentation, size, feathers pattern, dispersal etc. Similarly nests of birds are also having enormous distinctions in their size, shape, organization, material used, construction pattern, selection of site for nest and nest construction (Vyas, 2009).

Birds are vital and economically important as they provide ecosystem services such as pollination, seed dispersal in addition to recreation value provided by them (Sekercioglu, 2006; Whelan et al., 2015). Although Egrets, Herons, Water Hens are aquatic birds inhabiting water bodies for their food requirements but for nesting purposes they prefer trees (Sandhu, 1993). Forest provides many ecosystem services (Shvidenko et al., 2005). The alteration from native to exotic streetscapes saw the liberal damage of insectivorous and nectarivorous bird types reflecting a faith by these species on structurally varied and/or native vegetation for both shelter and food resources (Antos et al., 2003).

Bird community study undertaken at campus of Punjab Agricultural University, Ludhiana by choosing different tree species i.e. Eucalyptus globulus, grape (Vitis vinifera), sarin (Albizzia stipulata), lemon (Citrus limon), mango (Mangifera indica), dek (Melia azedarach), orange (Citrus sinesis), grapefruit (Citrus paradise), neem (Azdirachta indica) and simbal (Bombax malabaricum) revealed a total of 12 species of birds (Malhi and Kler 1999). Bird species that constituted the major bulk of community structure are House Crow, Common Myna, Common Babbler while Black Drongo, Cattle Egret, Red-vented Bulbul and Red¬wattled Lapwing constituted minor component on fruit and woody trees.

How to cite this article: Kaur, M. and Kumar, M. (2020). Nesting preferences of birds in relation to exotic trees in Ludhiana, Punjab. J. Anim. Res., 10 (1): 105-109.

In India agricultural lands such as agricultural field areas of Punjab that are widely cultivated have vast varieties of dairy, poultry, honeybee farms distributed between crop fields. Various kinds of native and exotic agro-forestry trees present along these farms and with these forests they also fulfil food requirements of birds in form of berries, nectar, fruits of trees, seeds etc. In agronomy double role of birds is well known (Ali, 1971). There are number of exotic trees that are being introduced in our country. Eucalyptus, Pines, Poplars are exotic species and are fast growing tree species in the world over. It is estimated that approximately 4.8 mha of Eucalyptus and 60,000 ha of Populus sps. is growing in India alone (Chandra, 2001).

The environmental influence of introduced plant occupation are recorded everywhere in addition to complexity of biological networks, ecosystem diversity, taxa, spatial and temporal scales (Vila et al., 2011; Pysek et al., 2012; Schirmel et al., 2016).

Study has revealed that Eucalyptus farms have a lesser number of animals species (Barlow et al., 2007; Proen^a et al., 2010; Calvino-Cancela et al., 2012) and bird species (Bongiorno,1982; Pina, 1989; Telleria and Galarza ,1990; Barlow et al., 2007; Proen^a et al., 2010; Calvino- Cancela, 2013; De la Hera et al., 2013), related to innate plantations. Allowing other varied plantations could lessen bird biodiversity damage (Calvino-Cancela, 2013), even though it would never exchange native forest habitations and their biodiversity abundance but nesting sites and food availability increases by increasing types of plantations.

Alterations in communal difference can in turn be explained by evaluating species incomings (Baselga et al., 2007). Species species interaction (nestedness) occurs when species accumulations in sites with fewer species are subdivisions of species accumulations at richer sites (Ulrich and Gotelli, 2007). Nest has been well-defined as a structure that supports the growth of the eggs and the existence of young (Collias and Collias, 1964). In distinction, spatial turnover suggests an organized replacement of some species by others, as a concern of ecological arrangement and old restraints (Qian et al.,2005).