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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Biology of the greyheaded parrot Poicephalus fuscicollis suahelicus Reichnow.

Symes, Craig Thomas. 30 October 2013 (has links)
This study was conducted to investigate the biology of the Greyheaded Parrot Poicephalus fuscicollis suahelicus in the wild. Field work was conducted in north-east South Africa in the southern limit of the range of the Greyheaded Parrot during two field seasons. Observations from August to December 1999 in the Levubu region, south of the Soutpansberg mountain range, included months of the non-breeding season when Greyheaded Parrots occur seasonally in the area. Observations in the Luvhuvhu-Mutale river confluence area from March to August 2000 included months of the breeding season. No field work was conducted from January to March 2000 due to exceptionally high rains in the southern African sub-region, that prevented access to sites. The Greyheaded Parrot has a widespread distribution, through southern, south Central and East Africa, that has possible changed little in recent years. However, local populations are likely to have suffered extinctions due to habitat destruction and capture for the illegal trade. Populations in protected areas (Makuya Park and Kruger National Park) are less vulnerable to capture than unprotected areas. The conservation of the Greyheaded Parrot outside of protected areas is highlighted. In various parts of the range of the Greyheaded Parrot seasonal movements occur in response to food and nest site availability. Nest sites are possibly limiting in certain parts of its range due to habitat destruction. During post-breeding flocking, the occurrence of larger flocks, possibly family units (mean ± S.E = 4.7 ± 0.2), is common, when birds wander in search for seasonally available food sources. During this period density of Greyheaded Parrots is 0.28 birds/100 ha. Monogamous pairs are more conspicuous during the breeding season (mean ± S.E = 2.1 ± 0.1) and density estimates are 0.14 birds/100 ha. Egg laying is synchronous between pairs with the timed appearance and flocking of juvenile flocks in spring (August/September). Breeding during the dry season reduces competition with other large cavity nesting bird species. Observations suggest that a skewed sex ratio exists in the population (males:females = 2:1). Daily movements are characterised by a bimodal activity pattern. Early morning movements involve flights to activity centres where the accumulation of numerous smaller flocks occur. Here preening, allo-preening and socializing occur with drinking and/or feeding occurring if food and/or water are available. Thereafter, birds move to regular feeding sites, to feed. Activity is decreased during the heat of the day with birds sleeping, resting and/or preening in the canopies of trees. Late afternoon activities involve increased levels of activity and late afternoon return flights to roosts. Greyheaded Parrots are specialist feeders, accessing the kernel of predominantly unripe fruit. This feeding strategy reduces competition with other frugivore competitors. During any one time few tree species are fed on by the Greyheaded Parrot. Greyheaded Parrots were also observed feeding on bark in the breeding season. Two, almost fully fledged, chicks were found dead in a nest and the causes of death undetermined. Their crops contained numerous pieces of masticated bark and insect parts. Behaviours and vocalizations of the Greyheaded Parrot were similar to that recorded in the Cape Parrot. Recognition of the Greyheaded Parrot as a separate species based on species specific calls and DNA warrants further investigation. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001.
2

Home range- and behavioural analysis of the Saddleback tamarin (Leontocebus fuscicollis) in Madre de Dios, Peru

Nymark, Marianne Kristine January 2023 (has links)
60% of primates in the world are threatened with extinction, while 75% have declining populations. The biggest threats to primates are the result of human activity. In this study, I have been looking at the primate Spix’s Saddleback tamarin (Leontocebus fuscicollis) and tried to estimate the home range size of four different study groups, while also trying to assess if there are differences in the type of trees in the areas where the tamarins are present compared to where they are absent. I have also compared the behaviour of the four different study groups. The data was collected in the Tambopata nature reserve in the Madre de Dios region in Peru during the summer of 2022, with the help and support from the research organisation Fauna Forever. To complement the observations, previously collected data from 2019-2021 was also used. The tamarins were followed using a group follow method, and the behaviour was noted every 10 minutes using an instantaneous scan sampling method. The tree composition data was gathered from previously created tree plots, made by the Fauna Forever staff. I found that the home range sizes of the four study groups varied between 2.6 ha and 17.9 ha. The data from the tree plots showed no statistically significant difference in where the tamarins chose to live. There was also no statistically significant difference between the four study groups in behaviour, except for how high up in the trees they groups spent their time. There was a lack of good data in this study, due to time- and material constraints, but overall the home ranges were of close to similar size as earlier studies, and the behaviour of the tamarins was in general also consistent with earlier studies. More research would be needed to answer the further questions that arose during this study concerning the ecological constraints of the tamarins home range.

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