. Bulletin of the British Ornithologists' Club. Birds. [ 104(3)] 98 The first chick fledged on 10 March (Day 21) aged 22-24 days and weighing The second fledged on 12 March (Day 23) aged 23 days and weighing $g. Skutch (1964) recorded the age at fledging of 2 chicks at one nest as 22 and 23 days and Davis (in Skutch 1964) described a nestling which fledged between 23 and 27 days of age. Only one adult Long-tailed Hermit was observed at the nest; since sexes are similar and only females of the family Trochilidae feed the young (Wetmore 1968) I took this bird to be
. Bulletin of the British Ornithologists' Club. Birds. [ 104(3)] 98 The first chick fledged on 10 March (Day 21) aged 22-24 days and weighing The second fledged on 12 March (Day 23) aged 23 days and weighing $g. Skutch (1964) recorded the age at fledging of 2 chicks at one nest as 22 and 23 days and Davis (in Skutch 1964) described a nestling which fledged between 23 and 27 days of age. Only one adult Long-tailed Hermit was observed at the nest; since sexes are similar and only females of the family Trochilidae feed the young (Wetmore 1968) I took this bird to be a female. The female's weight was recorded 3 times on 20 February during periods of brooding, these were 5-25g at , 5-oog at a:m. and at a-m- The weight growth curves of the summed weight for the 2 nestlings is shown in Figure 1. It should be noted that these figures are the mean weight of the nest and young minus the weight of the nest recorded on 12 March and as such does not account for any variations in the weight of the nest during the period of observation. Weight of Chicks gram 20i 15 10 5 1st Chick Fledges. 2nd Chick „ Fledges 8 16 18 20 22 24 10 12 14 Day Number Figure 1. Weight (average 15 min readings) of 2 Long-tailed Hermit Phaethornis supercilio- sus chicks combined in relation to day number (approximate age). No readings were taken on day 19. The nestlings were brooded on Day 1 for 22% of the daylight hours observed, in 4 periods averaging mins; on Day 2 for 15% of the day in 7 periods averaging mins; and on Day 3 for 4% of the day in 2 periods averaging mins. The adult did not brood the nestlings during the day after Day 3. The number of feeding visits per day to the chicks increased from 5 to 17 per day and decreased after the first chick fledged on Day 21 (Table 1). Table 1. Number of feeding visits to nest by parent Phaethornis superciliosus in relation approximate age of its 2 chicks Day No. 1234567 8 9 10 11 12 1
Size: 2566px × 974px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectbirds, bookyear1893
