scholarly journals The breeding biology of the Critically Endangered Seychelles Scops-owl Otus insularis: consequences for conservation and management

2004 ◽  
Vol 14 (2) ◽  
pp. 123-137 ◽  
Author(s):  
DAVE CURRIE ◽  
RODNEY FANCHETTE ◽  
JAMES MILLETT ◽  
CAMILLE HOAREAU ◽  
NIRMAL J. SHAH

The endemic Seychelles Scops-owl Otus insularis is a Critically Endangered restricted-range species currently recorded only from the montane forest of Mahé, the largest (152 km2) and highest (903 m) island in the granitic Seychelles. Limited research has been conducted on the species and, in particular, details of its breeding biology are poorly known. Behavioural observations were made on 12 pairs by the systematic monthly use of playback of conspecific calls, in conjunction with frequent non-playback territory visits from April 1999 to May 2001. A total of eight nests, including the first nest record, were found on three territories. All were in tree cavities (7–25 m high) and contained either a single egg or chick. This was consistent with additional observations of solitary fledglings (n = 11, from eight territories). Incubation lasted 3–4 weeks and the fledging period was 4–6 weeks (data from two nests). The timing of copulations, in conjunction with the detection of nests and fledglings, suggests that the scops-owl can breed throughout the year with peaks in nesting occurring around May and October. Sex roles during breeding were similar to those of other Strigidae owls: incubation was performed by the female; males courtship-fed the female prior to and during incubation, and the female and chick for the first 2 weeks post-hatching; and both parents fed older chicks and fledglings. Fledglings remained on territory for at least 3 months. Breeding success of study pairs was low: two of eight nests were successful and 11 fledglings (recorded from eight of 12 study territories) were observed in a 26-month period, equivalent to c. 0.5 fledglings per territory per year. Evidence suggests that alien predators may have been a factor limiting breeding success. We discuss the conservation implications of our findings.

2017 ◽  
Vol 28 (4) ◽  
pp. 606-619 ◽  
Author(s):  
CAROLINE BLANVILLAIN ◽  
THOMAS GHESTEMME ◽  
TEHANI WITHERS ◽  
MARK O’BRIEN

SummaryWe studied the breeding biology of Tahiti MonarchPomarea nigra, a ‘Critically Endangered’ forest bird endemic to Tahiti (French Polynesia). Nest activity was monitored from 1998 to 2002, and again from 2008 to 2015. During these 12 years, only 2–13 breeding pairs per year produced hatchlings. Egg-laying occurred all year, but usually increased between August and January, peaking around November. Of the 200 nests monitored, 33 (16%) were abandoned shortly after construction, 71 had an egg laid immediately after the nest were completed (34 %) and 96 nests (46 %) had a pre-incubation phase of 18.9 ± 1.9 days (3–62 days;n= 47 nests), during which the birds visited the nest on an irregular basis. Half (49 of 96) of these nests were abandoned before an egg was laid, with incubation subsequently commencing at the remaining nests (n= 47). Although both sexes incubated for an average of 13.6 ± 0.3 days (range 13–15), the female usually spent more time incubating than the male. Only one young per nest was ever observed. The average nestling phase was 15.5 ± 0.7 days (range 13 to 20 days). Parents continue to feed the young after fledging for 74 ± 4.7 days (range 42–174). As with many tropical island endemics, the Tahiti Monarch has low reproductive productivity as indicated by the fact that: 1) only 56% of pairs attempt to lay an egg in any one year, 2) most pairs attempt only one brood per year and 3) the considerable length of the nesting and fledging phases. Because of its low productivity, maximising the reproductive success of the Tahiti Monarch is essential to secure its recovery.


2013 ◽  
Vol 31 ◽  
pp. 31-34
Author(s):  
Noor Jahan Sarker ◽  
M Firoj Jaman ◽  
Shariar Mustafa ◽  
Md Saidur Rahman

Breeding biology of the Coppersmith barbet, Megalaima haemacephala (Müller, 1776) was carried out between February, 2006 and January, 2007 at Sharawardy Uddyan, Ramna Park, Curzon Hall and National Botanical Garden. The breeding season started from December and ended in June. In total 20 nests were observed, of which 10 nests were studied in details in four study areas. The coppersmith barbet mostly preferred to make holes on the branches of koroi (Albizzia procera) for nesting. Egg laying started on 15th February in the study areas. Average height of nests from the ground was 9.7m and average depth and diameter of the holes was 29.20cm and 4.46cm respectively. New holes were constructed yearly or the old one was reused. Both the sexes took part in incubation of eggs, brooding and feeding to the nestlings. A total of 30 eggs were laid in 10 nests. Clutch size varied from 2 – 4 eggs (average: 3 eggs). Among them, 20 (66.67%) eggs were hatched and the rest 10 (33.33%) were unhatched and lost. Average incubation period was 14 days. The male and the female incubated the eggs for an average of 27.44 minutes/ hours and 32.56 minutes/ hours, respectively. Average number of nestlings (brood size) per nest was 2. Out of 20 nestlings, 16 left their nests successively. The breeding success was 53.33% in relation to the number of eggs laid and 80% in relation to nestlings hatched. The average weight of eggs and nestlings was 3.59g and 9.33g, respectively. The main causes of loss of the eggs and nestlings were human interference, predation and ectoparasitic infections. Insects and fruits were fed to the nestlings by their parents.DOI: http://dx.doi.org/10.3329/ujzru.v31i0.15397Univ. j. zool. Rajshahi Univ. Vol. 31, 2012 pp. 31-34 


Ibis ◽  
2008 ◽  
Vol 142 (2) ◽  
pp. 305-311 ◽  
Author(s):  
ANTON KRISTIN ◽  
HERBERT HOI ◽  
FRANCISCO VALERA ◽  
CHRISTINE HOI

2009 ◽  
Vol 57 (6) ◽  
pp. 433 ◽  
Author(s):  
Luis Ortiz-Catedral ◽  
Jonathan C. Kearvell ◽  
Mark E. Hauber ◽  
Dianne H. Brunton

We studied a population of the critically endangered Malherbe’s parakeet (Cyanoramphus malherbi), following the release of 62 captive-bred individuals on Maud Island, New Zealand, to identify and characterise nesting sites in a novel island environment. Previous work on Malherbe’s parakeets consisted of limited observations on remnant mainland populations. The age of breeding pairs on Maud Island was 7.2 ± 4.7 months and included both captive-bred individuals of the first release flock and individuals hatched on Maud Island within a year of the first release. Nests were found in hollows of mamaku (Cyathea medullaris), vacant nests of sacred kingfisher (Todiramphus sanctus), a hole in the ground and a hollow in a kohekohe (Disoxylum spectabile). Active nests were found in the austral spring, summer and autumn. Clutch size was 5 eggs. The fledging of three Malherbe’s parakeets was confirmed for one nest 43 days after hatching. Observations of newly fledged individuals around the island indicate that at least seven successful nesting attempts occurred. Consistent with other studies in Cyanoramphus parakeets, our results suggest that availability of nesting sites on small islands may not be a limiting factor for the establishment of additional populations of Malherbe’s parakeets via captive breeding and translocation. The formation of breeding pairs at an early age, the use of diverse nesting sites in regenerating vegetation, and the evidence of successful breeding shortly after release on an island represent encouraging prospects for the conservation of New Zealand’s rarest parakeet.


2020 ◽  
Vol 10 (23) ◽  
pp. 12870-12882
Author(s):  
Igor Salles‐Oliveira ◽  
Taís Machado ◽  
Karina Rodrigues da Silva Banci ◽  
Selma M. Almeida‐Santos ◽  
Maria José de J. Silva

Oryx ◽  
2015 ◽  
Vol 50 (2) ◽  
pp. 344-354 ◽  
Author(s):  
Kim E. Reuter ◽  
Haley Gilles ◽  
Abigail R. Wills ◽  
Brent J. Sewall

AbstractOverexploitation is a significant threat to biodiversity, with live capture of millions of animals annually. An improved understanding of live capture of primates is needed, especially for Madagascar's threatened lemurs. Our objectives were to provide the first quantitative estimates of the prevalence, spatial extent, correlates and timing of lemur ownership, procurement methods, within-country movements, and numbers and duration of ownership. Using semi-structured interviews of 1,093 households and 61 transporters, across 17 study sites, we found that lemur ownership was widespread and affected a variety of taxa. We estimate that 28,253 lemurs have been affected since 2010. Most lemurs were caught by owners and kept for either short (≤ 1 week) or long (≥ 3 years) periods. The live capture of lemurs in Madagascar is not highly organized but may threaten several Endangered and Critically Endangered species.


2021 ◽  
Vol 47 (1) ◽  
pp. 23-34
Author(s):  
Habibon Naher ◽  
Noor Jahan Sarker ◽  
Shawkat Imam Khan

The breeding biology of the common kingfisher (Alcedo atthis) was studied from 2008 to 2011 in Dhaka North City Corporation and Savar Upazilla. The breeding season was April to September. It laid 3 to 7 glossy white, almost round eggs with a size of 2.5±0.3 cm length, 2.2±0.3 cm breadth, and 5.3±0.7g weight. It incubated for 16 to 21 days. During hatching, the hatchlings’ weight ranged from 8.5 to 10.5 g and total body length from 43.2 to 58.6 mm whereas, it was 30.1 to 32.7 g and 151 to 155.5 mm, respectively, during fledging. Hatching success was 83.3%. Stolen by people (13.9%) and infertility (2.8%) were the causes of egg loss. The young birds fledged out after 21 to 27 days of hatching. A total of 56.7% of nestlings were unable to fly due to stolen (43.3%), deaths due to unknown reasons (6.7%) and deaths due to natural disaster (6.7%). The breeding success was 36.1% in relation to eggs laid and 43.3% in relation to eggs hatched. J. Asiat. Soc. Bangladesh, Sci. 47(1): 23-34, June 2021


2018 ◽  
Vol 14 (3) ◽  
pp. 20170688 ◽  
Author(s):  
Adriana Suarez-Gonzalez ◽  
Christian Lexer ◽  
Quentin C. B. Cronk

Introgression is emerging as an important source of novel genetic variation, alongside standing variation and mutation. It is adaptive when such introgressed alleles are maintained by natural selection. Recently, there has been an explosion in the number of studies on adaptive introgression. In this review, we take a plant perspective centred on four lines of evidence: (i) introgression, (ii) selection, (iii) phenotype and (iv) fitness. While advances in genomics have contributed to our understanding of introgression and porous species boundaries (task 1), and the detection of signatures of selection in introgression (task 2), the investigation of adaptive introgression critically requires links to phenotypic variation and fitness (tasks 3 and 4). We also discuss the conservation implications of adaptive introgression in the face of climate change. Adaptive introgression is particularly important in rapidly changing environments, when standing genetic variation and mutation alone may only offer limited potential for adaptation. We conclude that clarifying the magnitude and fitness effects of introgression with improved statistical techniques, coupled with phenotypic evidence, has great potential for conservation and management efforts.


Sign in / Sign up

Export Citation Format

Share Document