Breeding Behaviour and Vocalisations of Oriental Magpie Robin, Copsychus saularis musicus (Aves: Turdidae) in Suburban Areas in Kota Samarahan, Sarawak.

• Main Author: Zahran, Bin Mansor
• Format: Thesis
• Language: English
• Published: Universiti Malaysia Sarawak (UNIMAS) 2019
• Subjects: Q Science (General); QL Zoology
• Online Access: http://ir.unimas.my/id/eprint/26103/2/Zahran%28fulltext%29.pdf; http://ir.unimas.my/id/eprint/26103/
• Institution: Universiti Malaysia Sarawak

A study on breeding behaviour and vocals characteristics of one of an understudied tropical bird species in Borneo, the Oriental Magpie robin (Copsychus saularis) has been conducted from March 2015 until May 2017 in UNIMAS campus areas and Tanjung Bundong village areas. The study was aimed to improve an understanding on nest characteristics, incubation and food provisioning behaviour together with the vocalisations of this species during breeding season. Throughout the study period, the breeding activities of Magpie robin occurred from December until mid-September. The peak of breeding activities occurred on April based on three years of pooled data. A total of 12 nesting sites have been discovered from eight colour-banded breeding pairs (A, B, C, D, E, F, G and H). Most of nests were found to be constructed in hidden cavities of building. The clutch size of Magpie robin was 2.94 ± 0.14 eggs. The incubation phase was 13.75 ± 0.61 days. Females spent an average of 27.06 ± 0.54 minutes per hour incubating eggs while 32.69 ± 0.59 minutes per hour off the nest daily during incubation phase. There was no significant differences between the incubation session of morning (0700-0900 hr), afternoon (1200-1400 hr) and evening (1630-1830 hr) (F = 35.08, df = 2, 36, P = 3.52). There was a positive correlation between time spent incubating eggs and incubation phase’s day (Spearman’s rho = 0.99). Magpie robin exhibited bi-parental provisioning behaviour throughout nestling phase. Females made significantly higher provisioning trips, 3.91 ± 0.10 trips per hour compared to male, 2.45 ± 0.11 trips per hour (t = 3.96, df = 23, P = 0.0006). Parents made more provisioning trips in the nest containing higher number of nestlings (F = 3.75, df = 3, 52, P = 0.01). Nestlings were fed more as they become older. There was a positive correlation between parental provisioning trips and nestling’s phase day (Spearman’s rho = 0.16). There was no significant differences between the parental feeding activities during morning (0700-0900 hr), afternoon (1200-1400 hr) and evening (1630-1830 hr) (F = 0.23, df = 2, 39, P = 0.78). The duration of nestling phase was 15.33 ± 0.42 days. A total of six call types were successfully identified from 38 individuals of Magpie robin (8 males, 6 females, 10 juveniles and 14 young) and were identified as (i) territorial calls, (ii) threat calls, (iii) submissive calls, (iv) begging calls, (v) juvenile calls and (vi) distress calls. Throughout the breeding season, males were observed to utter territorial song mostly in the morning. A total of 112 song types were managed to be identified from 50 minutes of total duration of recordings in each of five males. Among those 112 song types, 26 song types were produced by male A, 28 songs by male B, 17 songs by male C, 18 songs by male E and 23 songs by male G. There was no significant difference between breeding territory size during incubation period, 18,719 ± 794.80 m2 and nestling period, 18,136.99 ± 735.01 m2 (t = 0.009, df = 14, P = 0.99). Song complexity of males was positively correlated with the secured territorial size but was not significant (r = 0.786, P = 0.115). The territorial song, territorial call and threat call were substantially important throughout breeding season as these vocalisations help to secure the breeding territories, keeping the nesting sites from any form of disturbances. Keywords: Magpie robin, breeding behaviour, vocalisation, song repertoire, song complexity