Comparative nesting patterns and success of Mynas and Starlings (Aves: Sturnidae) inhabiting Jahangirnagar University campus, Bangladesh

Abstract

Nesting patterns of four species of mynas and starlings, Common Myna (Acridotheres tristis), Jungle Myna (Acridotheres fuscus), the Asian-pied Starling (Gracupica contra) and Chestnut-tailed Mtarling (Sturnia malabarica) were studied in Jahangirnagar University campus from March to September in 2016. Nests were searched systematically throughout the study area and nesting parameters like nest dimensions, nest-site selection, tree species preference, nesting materials, clutch size and nesting success were examined. A total of 101 nests were recorded where 31 nests were of Common Myna, 10 of Jungle Myna, 49 of the Asian-pied Starling and 11 nests were of Chestnut-tailed Starling. Overall, the sturnids preferred nesting on trees (n=84) to anthropogenic structures (n=17). Common myna showed maximum variation in nest-site selection using tree holes (n=12), tree branches (n=10) and building cornices, holes or crevices (n=9) whereas Chestnut-tailed Starling nested only in tree cavities (n=11). Jungle Myna built nests both in tree holes (n=4) and in building holes and crevices (n=6). The Asian-pied Starlings built their domed nests mostly on tree branches (n=47) where 69% nests were peripheral and 31% were central in position. Out of 20 species of trees utilized for nesting purpose, the majority of nests were built on Whites iris Albizia procera (n=18) followed by Neem Azadirachta indica (n=10) and Mahogany Swietenia mahagoni (n=10). The nests were constructed between 2 and 18m (8±3.8m) from the ground level. Among 19 types of nesting materials recorded, twigs, leaves, straws, grasses, feathers, plastics and polythene were frequently used by all four species while the Asian-pied starling used more rubbish materials than other species. Highest nesting success (80%) was recorded in Common Myna whereas the Asian-pied Starling, Chestnut-tailed Starling and Jungle Myna had 77.8%, 75% and 66.7% of nesting success respectively. Adaptions to using different nesting sites in Common Myna and comparatively higher nesting height in the Asian-pied Starling may have facilitated the greater nesting success.
 Bangladesh J. Zool. 48(2): 321-334, 2020

Nest site selection of cavity-nesting birds at Jahangirnagar University campus, Bangladesh

“…In our study, more than 50% of total nest cavities were found in three species of trees (Swietenia mahagoni, Abizia procera and Samania saman) of > 42 cm in DBH. Earlier studies also showed that these trees are commonly found at JU campus and provide nesting resources to a wide variety of birds including cavity nesters (Jahan et al 2018;Shoma & Begum, 2020;Shoma, 2021).…”

“…Nest height above ground plays a significant role in nest protection and therefore, nest site selection is often influenced by cavity height along with surrounding vegetations (Fisher & Wiebe, 2005;Nyirenda et al, 2016). Nests placed at lower height are more prone to predation and it is evident from previous studies that nest disappearance and destruction through anthropogenic disturbances are more frequent in nests at under 5 m (Jahan et al, 2018;Shoma & Begum 2020). Average nest height of cavity-nesting birds at JU campus was above 5 m which could be advantageous in minimizing predation risk and in reducing human interference.…”

“…Jahangirnagar university campus is home to about 195 species of birds which comprises about 30% of the total bird species in Bangladesh (Begum, 2016). The diverse habitat features made the campus an attractive nesting and roosting ground for a broad range of bird communities including several species of primary and secondary cavity-nesting birds (Mohsanin & Khan, 2009;Rahman et al, 2019;Shoma & Begum, 2020;Shoma, 2021). However, habitat fragmentation and continuous loss of trees due to growing infrastructure developments may threaten the reproduction and survival of cavity-nesting birds in the campus.…”