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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.
11

The nutritional ecology of frugivorous birds in Hong Kong

Ko, Wai-ping, Ice., 高惠冰. January 1999 (has links)
published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy
12

Fruit neighborhoods and interactions between birds and plants in Puerto Rico

Saracco, James Frederick, January 2001 (has links)
Thesis (Ph. D.)--North Carolina State University, 2001. / Title from PDF t.p. (viewed on Dec. 8, 2005). Vita. Includes bibliographical references.
13

Birds and figs in Hong Kong

So, Ngai-hung, Samson., 蘇毅雄. January 1999 (has links)
published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy
14

Aspects of the thermal physiology and fruit digestion of Knysna (Tauraco Corythaix) and Purple-crested (Gallirex porphyrelophus)

Wilson, Amy-Leigh. 22 October 2013 (has links)
Chapter 2: Avian frugivores have been somewhat poorly studied with regards to the effects that different fruit sugar types and concentrations have on their digestive efficiencies. Digestion of sugars in equicaloric and equimolar artificial fruit of different sugar types at varying concentrations and molarities were therefore investigated in two relatively large South African frugivores, the Knysna (Tauraco corythaix) and the Purple-crested (Gallirex porphyreolophus) Turaco. Artificial fruits of 6.6, 12.4 and 22% sucrose and glucose respectively and artificial fruits of 0.42, 0.83 and 1.66 mol L-1 sucrose and glucose respectively were used to determine daily food and energy intake, digestive efficiencies and digestive transit times. Digestive transit times of both Turaco species were slower with an increase in sugar concentration and molarity, irrespective of sugar type. Food intake of both Turaco species increased with decreasing concentration and molarity, irrespective of sugar type suggesting compensatory mechanisms for energy requirements. Apparent assimilation efficiencies of both Turaco species ranged from 61.4-90.0% and 60.2-92.4% for equicaloric and equimolar artificial fruit diets respectively. Consequently these two frugivores appear to be tolerant of sugar type and would be expected to select fruits based on energy yields. Future studies of the composition of indigenous forest fruit sugars may give insight into food preferences of the Turaco species and their role as potential seed dispersers of fruiting tree species. Chapter 3: The effects that different fruit sugar types and concentrations have on food preferences of avian frugivores have been relatively poorly studied. Although it has been recently advocated that preference is based on equicaloric energy it is also important to note whether preferences change as energy content changes. Therefore, sugar preferences of equicaloric and equimolar artificial fruit of different sugar types at varying concentrations and molarities were investigated in two relatively large South African frugivores, Knysna (Tauraco corythaix) and Purple-crested (Gallirex porphyreolophus) Turacos. Artificial fruits of 6.6, 12.4 and 22% sucrose and glucose respectively and artificial fruits of 0.42, 0.83 and 1.66 mol L-1 sucrose and glucose respectively were used to determine sugar preferences. Knysna Turacos preferred the sucrose to the glucose equicaloric artificial fruit diet at low concentrations whereas Purple-crested Turacos showed no preference for either diet. Both Turacos species preferred the sucrose equimolar artificial fruit diet to the glucose at low concentrations. At high concentrations neither species showed a preference for either equicaloric or equimolar artificial fruit diets. This suggests that energy requirements influence food preferences more than sugar type and that birds will select fruit that is higher in energy irrespective of sugar type. This complements an earlier study on digestion of sugars at varying concentrations of differing equicaloric and equimolar artificial fruit sugar types. It again emphasizes the need for future studies looking at the composition of indigenous forest fruit sugars in order to obtain insight into the role of these avian frugivores as potential seed dispersers of fruiting tree species. Chapter 4: Avian frugivores may select fruit based on their seed loads and pulp to seed ratios and this may have important implications for their role as seed dispersal agents. Consequently the effect of different seed packaging was investigated in two relatively large South African frugivores, Knysna (Tauraco corythaix) and Purple-crested (Gallirex porphyreolophus) Turacos. Small-seeded artificial fruits containing on average five black plastic beads (2.24 mm diameter) and large-seeded artificial fruits containing one average one single black plastic bead (3.85 mm diameter) were used to investigate transit rates and food preference. Total seed volume in the two fruits was on average approximately equal (29.42 mm3 and 29.88 mm3 for small- and large-seeded fruits, respectively). Bead transit rates ranged from 38-45 min for Knysna Turacos and 36-50 min for Purple-crested Turacos with faster transit rates on the small-seeded diet. Pulp transit rates ranged from 25-39 min for Purple-crested Turacos and 34-40 min for Knysna Turacos. Purple-crested Turacos had significantly shorter pulp transit rates on the large-seeded than the small-seeded diet whereas Knysna Turacos had no significant difference between diets. Knysna Turacos preferred the small-seeded to the large-seeded artificial fruits whereas Purple-crested Turacos showed no preference for either diet. Further studies on avian dispersers will contribute to a greater understanding of their evolutionary relationship with fruiting plants. In particular, future studies establishing suitable seed sizes and volumes for use in determining the effect of seed packaging on larger birds are required as well as studies looking at seed packaging of indigenous forest fruit and the effects of seed packaging on digestion and food preference in indigenous avian frugivores may give insight into the role of avian frugivores as fruit consumers and seed dispersers. Chapter 5: Fleshy-fruited plants and frugivores share a mutualistic relationship with plants offering the frugivores a reward of fleshy fruit pulp in order to disperse their seeds. In return frugivores receive a food source and consequently a source of energy. However all fruits are not equal in terms of available energy and consequently the digestion efficiency of six indigenous tree species was investigated in an avian frugivore, the Knysna Turaco (Tauraco corythaix). It was predicted that the Turacos would process these indigenous fruits efficiently and have fast transit rates and high intake rates irrespective of species. Fruits were fed to the Turacos in separate trials to determine daily food and energy intake, digestive efficiencies and digestive transit times. Digestive transit times of Knysna Turacos (c. 12-28 min) fall within the range of published examples for other frugivorous birds. Apparent assimilation efficiencies of the Turacos ranged from c. 15-84% and were generally lower than those observed in other avian frugivores. Future studies looking at the nutritional composition of indigenous forest fruit may provide insight into the Knysna Turacos digestive efficiency and consequently their food preferences and role as potential seed dispersers of fruiting tree species. Chapter 6: Seed dispersal plays an important role in the persistence, regeneration and maintenance of plant communities. It is therefore not surprising that much attention has been paid to the germination potential of seeds ingested by frugivorous animals. Consequently the aim of this study was to determine what effect ingestion of seeds by Knysna Turacos (Tauraco corythaix) has on the germination rate and germination percentage of indigenous South African tree species. Fruits from twelve tree species were fed to the Turacos in separate trials and seed retention times were determined as it has been suggested that a longer seed retention time may increase germination rates. At the end of each trial, seeds were extracted from excreta of individual birds and planted in trays containing potting soil. Germination was recorded daily until 14 days post of no germination. Knysna Turacos seed retention times were in the range of those obtained by other studies with Ficus sur seeds having the fastest retention times (12.4 ± 0.8 min) and Celtis africana the slowest (34.6 ± 5.6 min). Mean percentage germination of ingested seeds was not significantly different to pulp removed and whole fruit seeds indicating that ingestion by Knysna Turacos did not enhance percentage germination through either seed coat abrasion or pulp removal. Seed ingestion by Knysna Turacos did not influence the rate at which seeds germinated in 75 % of the tree species while it did for ingested F. lutea, F. natalensis and F. sur seeds which germinated significantly sooner than whole fruit seeds. Future studies relating the composition of indigenous forest fruits to food preferences of Knysna Turacos may give insight into their role as potential seed dispersers of indigenous fruiting tree species. Chapter 7: Frugivorous animals play a major role in dispersing tropical, and to a lesser extent, temperate tree species. In order to attract potential seed dispersers, plants generally offer a reward of fleshy fruit pulp. Criteria for fruit choice by avian frugivores are influenced by a number of non-nutritive (e.g. fruit size and colour) factors; and nutritional composition of the fruit. There is a paucity of nutritional composition and other fruit trait data of indigenous South African fruit. This information is necessary in order to determine which frugivores are likely to ingest which fruits and consequently act as potential seed dispersal agents. This information would provide us with an understanding of the inter-relationships between indigenous fruit and frugivores in South Africa. Consequently nutritional composition was investigated in various indigenous fruit species that avian frugivores feed on. Fruits were collected from 38 indigenous tree species found in KwaZulu-Natal afromontane and coastal forests. Pulp was freeze-dried to constant mass and then analyzed for sugar, lipid and protein content; and for water content determination. Fruit width in this study ranged from 4 mm (Searsia rehmanniana and Trema orientalis) to 40 mm (Annona senegalensis, Ficus sur and Xylotheca kraussiana). Of the fruits examined in this study 29% were black and 43% red when ripe. Most (84%) fruit species analysed for sugar content were hexose dominant with 50% being fructose and 34% being glucose dominant. Only 16% of the fruit species analysed were sucrose dominant. Fruits in this study were generally observed to be high (mean: 68.1 ± 3.3%; n = 30) in water content; and low in protein and lipid content respectively (mean: 8.2 ± 0.5%; 9.3 ± 2.2%; n = 30) indicating that these fruits species could be considered as nutrient-dilute. Future studies need to determine the nutritional composition of the remaining indigenous South Africa fruit in order to develop a comprehensive database as well as examining non-nutritive factors. Together this information would play a key role in understanding fruit preferences and consequently seed dispersal and would therefore be useful in developing management plans for forest conservation. Chapter 8: Many seasonal thermoregulation studies have been conducted on Holarctic birds that live in predictable, highly seasonal climates with severe winters. However, relatively few studies have been conducted on their southern hemisphere Afrotropical counterparts that encounter less predictable climates with milder winters. These latter birds are expected to conserve energy in winter by down-regulating their metabolic rates. Therefore in this study, metabolic rate was measured during summer and winter in Knysna Turaco, Tauraco corythaix (Musophagiformes, Musophagidae) (c. 310 g), a non-passerine, in order to test whether there is energy conservation in winter. No overall significant differences in resting metabolic rates over a range of ambient temperatures were observed between winter and summer. However, whole-organism basal metabolic rates were 18.5 % higher (p = 0.005) in winter than in summer (210.83 ± 15.97 vs. 186.70 ± 10.52 O2 h-1). Knysna Turacos had broad thermoneutral zones ranging from 20-28 oC in winter and 10-30 oC in summer. These results suggest that Knysna Turacos show seasonal thermoregulatory responses that represent cold defense rather than energy conservation, which is contrary to what was expected. Keywords: sugar digestion, sugar preference, seed packaging, basal metabolic rate (BMR), resting metabolic rate (RMR), phenotypic flexibility, indigenous fruit, germination percentage, germination rate, fruit sugars, protein, lipids, fruit size, fruit colour, Knysna Turaco, Purple-crested Turaco. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
15

Reproductive phenology and fruit production on a land bridge island in the brazilian atlantic forest /

Genini, Julieta. January 2006 (has links)
Resumo: As florestas tropicais estão entre os ambientes mais produtivos do planeta, sendo que a quantidade de frutos kg/ha pode chegar a 180-1000 kg/ha. Apesar dessa alta produtividade, a fenologia é altamente sazonal, ocorrendo períodos de escassez de recursos e alta produtividade no mesmo ano e/ou entre anos. Os frugívoros exibem uma ampla variedade de adaptações comportamentais e ecológicas para superar esses períodos de escassez. O presente trabalho avaliou as variações temporais na disponibilidade de frutos consumidos por vertebrados frugívoros na Ilha Anchieta, São Paulo, Brasil. Nós procuramos responder às seguintes questões: Os padrões de frutificação e disponibilidade de frutos diferem entre arbóreas e palmeiras? e Os padrões fenológicos de frutificação diferem entre grupos de palmeiras com diferentes síndromes de dispersão?. Os padrões fenológicos foram sazonais para ambos os grupos, no entanto, as datas de ocorrência dos eventos de frutificação foram diferentes. A produção de frutos também foi diferente entre palmeiras e arbóreas, sendo que as palmeiras constituíram mais de 80 por cento do total da biomassa coletada. Os padrões fenológicos foram diferentes entre as palmeiras com diferentes sub-síndromes de dispersão (dispersas por roedores, mistas e aves) fornecendo recursos alimentares para diferentes grupos de frugívoros ao longo do ano. As palmeiras poderiam constituir um recurso alimentar alternativo em períodos de baixa disponibilidade de frutos embora não forneçam recursos para os diferentes tipos de frugívoros da Ilha Anchieta o ano todo. / Abstract: Tropical rainforest is considered one of the world’s most productive habitats where fruit biomass ranges between 180-1000 kg/ha/yr. Despite this broad fruit production, phenology is highly seasonal in tropical forests, showing alternate periods of fruit scarcity and high resource production both in the same year and/or between different years. Frugivores exhibit a variety of ecological and behavioral adaptations to overcome these fluctuations. We evaluate the temporal variation in the availability of fruits consumed by vertebrate frugivores on Anchieta Island, in the Brazilian Atlantic Forest, Northeast São Paulo State. We aim to answer the following questions: Do fruiting patterns and the availability of fruits consumed by vertebrate frugivores differ between palms and trees? Do palm fruiting patterns differ among seed dispersed groups (rodent, mixed and bird)? Phenological patterns were seasonal for both trees and palms; however, the times of occurrence of fruiting differed. Fruit fall biomass was also different between trees and palms, and palms constituted more than 80 percent of the overall fruit fall biomass. Phenological patterns differed between the seed dispersed palms groups (rodent, mixed and bird seed dispersed palms) providing food resources in distinct periods for different assemblages of vertebrate frugivores. Palms may constitute an alternative food resource in periods of low fruit availability, although they do not provide resources for the entire assemblage of vertebrate frugivores on Anchieta Island all year. / Orientador: Mauro Galetti Rodrigues / Coorientador: Leonor Patrícia Cerdeira Morellato / Banca: Marco Aurélio Pizo Ferreira / Banca: Valesca Bononi Ziparro / Mestre
16

Ecologia alimentar do cuxiu-de-nariz-vermelho Chiropotes albinasus (Primates : Pitheciidae) na Floresta Nacional do Tapajos, Para / Feeding ecology of the red-nosed saki monkey Chiropotes albinasus (Primates : Pitheciidae) at Tapajos National Forest, Para State

Pinto, Liliam Patricia 29 January 2008 (has links)
Orientador: Eleonore Zulnara Freire Setz / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T19:06:22Z (GMT). No. of bitstreams: 1 Pinto_LiliamPatricia_D.pdf: 1402160 bytes, checksum: 5781b9e9527706d97db9acae22b9a353 (MD5) Previous issue date: 2008 / Resumo: A ecologia de um grupo cuxiú-de-nariz-vermelho (Chiropotes albinasus) foi estudada entre agosto de 2004 e janeiro de 2006 em uma mata primária na Floresta Nacional do Tapajós, Pará. Para analisar a disponibilidade de itens e preferências por alimentos, foi realizado em 16 parcelas de 25 x 25 m (1 ha) um levantamento florístico e um monitoramento fenológico na área de estudo. A dieta e o padrão de atividades diárias de C. albinasus foram investigados pelo método de varredura instantânea. Esta pesquisa está entre os estudos de maior esforço amostral já realizados com o gênero Chiropotes. Durante 38 dias completos distribuídos em onze meses, os cuxiús se alimentaram de 125 espécies de plantas pertencentes a 38 famílias (n = 5.197 registros de alimentação). Brosimum parinarioides (Moraceae) foi a fonte de alimentos mais utilizada (9,5% dos registros), e teve um alto índice de seletividade. Sementes imaturas foram os itens mais consumidos (48,2%), seguidas de polpa de frutos maduros (39,2%) e sementes maduras (6,0%). A maior parte do tempo (n = 22.373 registros) foi gasta em viagem (36,3%) e repouso (27,5%). As atividades de alimentação somaram 23,8% dos registros e a socialização 8,8%. O grupo teve um tamanho máximo de 56 membros e apresentou uma dinâmica de agrupamento muito variável. Os subgrupos podiam permanecer fissionados por algumas horas ou por vários dias, um padrão diferente do observado em outros estudos com cuxiús. A área de vida de 1.000 ha é uma das maiores já registradas para primatas neotropicais. A desigualdade na distribuição espacial e temporal dos recursos alimentares afeta a ecologia alimentar dos cuxiús-de-nariz-vermelho, que selecionaram espécies mais produtivas e ajustaram seus padrões de forrageio de acordo a oferta de alimentos / Abstract: The ecology of a group of red-nosed bearded sakis (Chiropotes albinasus) was studied between August 2004 and January 2006 in continuous primary forest at the Floresta Nacional do Tapajós, Pará. To investigate food availability and food preferences, tree composition, forest structure and phenology were measured in 16 plots of 25 x 25 m, totaling 1 ha. C. albinasus diet and activity budgets were recorded by instantaneous scan method. This study represents the largest study of Chiropotes in continuous forest. During 38 complete observation days over eleven months, bearded sakis fed on 125 plant species from 38 families (n = 5,197 feeding records). Brosimum parinarioides (Moraceae) was the most used food source (9.5% of records), and has a high selectivity index. Immature seeds were the most consumed items (48.2%), followed by ripe fruit pulp (39.2%) and mature seeds (6.0%). Most time (n = 22,373 activity records) was spent in traveling (36.3%) and resting (27.5%). Feeding represented 23.8% of the records and social activities 8.8%. The group with up to 56 individuals could subdivide in subgroups of variable sizes, which could remain apart for some hours or up to several days. This grouping dynamic differed from other studied bearded sakis. Home range was estimated in more than 1000 ha, one of the largest recorded for a Neotropical primate. Food resource heterogeneity in space and time influenced feeding ecology of the red-nosed bearded saki, which showed preference for more productive plant species and adjusted their foraging patterns to food availability / Doutorado / Doutor em Ecologia
17

Interação ecológica entre mamíferos terrestres frugívoros e palmeiras neotropicais /

Freitas, Paula Akkawi de. January 2019 (has links)
Orientador: Mauro Galetti / Resumo: As palmeiras são consideradas um recurso chave para os mamíferos terrestres tropicais. Entretanto, como as hiper-diversas guildas de frugívoros das florestas tropicais exploram recursos de palmeiras e coexistem, ainda é pouco compreendido. Neste trabalho, avaliamos como três espécies de mamíferos frugívoros terrestres, o queixada (Tayassu pecari), seu parente próximo, o cateto (Pecari tajacu) e a cutia (Dasyprocta azarae) interagem entre si e com os frutos de três espécies de palmeiras em uma floresta tropical da Mata Atlântica do Brasil. Utilizamos armadilhas fotográficas e modelos de ocupação para examinar as interações competitivas entre eles. Ao contrário de nossas expectativas, não encontramos evidências de exclusão competitiva entre esses frugívoros. Os queixadas exploraram principalmente as áreas de grande abundância da palmeira hiper-dominante Euterpe edulis, enquanto as cutias concentraram seu forrageamento em áreas com grande abundância de Syagrus oleracea e, em menor escala, Syagrus romamzoffiana. Os queixadas também responderam positivamente a Syagrus oleracea, mas apenas na ausência de cutias. Os catetos preferiram áreas de alta abundância de Syagrus romamzoffiana onde as outras duas espécies apresentaram baixa detecção ou estavam ausentes. Estes resultados sugerem que, apesar de ocuparem habitats semelhantes, estarem ativos durante as mesmas horas e compartilharem recursos de palmeiras semelhantes, as estratégias comportamentais dessas espécies permitem que elas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Palm fruits are considered a key resource for tropical terrestrial forest-dwelling mammals. Yet, how hyper-diverse assemblies of frugivores in tropical forests exploit palm resources and coexist despite high diet overlap remains poorly understood. Here, we evaluate how three species of terrestrial frugivorous mammals, the white-lipped peccary (Tayassu pecari), their close relative the collared peccary (Pecari tajacu) and the agouti (Dasyprocta azarae), interact with each other, and with the fruits of three palm species in a tropical Atlantic Forest of Brazil. We used cameras-traps and occupancy models to examine competitive interactions amongst them. Contrary to our expectations, we found no evidence of competitive exclusion amongst these frugivores. White-lipped peccaries primarily exploited areas of large abundance of the hyper-dominant palm Euterpe edulis, whilst agoutis concentrated their foraging on areas with large abundances of Syagrus oleracea and, to a lesser extent, Syagrus romamzoffiana. White-lipped peccaries also responded positively to Syagrus oleracea, but only when agoutis were absent. Collared peccaries preferred areas of high abundance of Syagrus romamzoffiana where the other two species showed low detection or were absent. These results suggest that despite occupying similar habitats, being active during the same hours and sharing similar palm resources in an isolated forest fragment, behavioural strategies of these species allow them to coexist. / Mestre
18

Fruiting strategies of the woody vine Parthenocissus quinquefolia

Pacey, Carol. January 1985 (has links)
Call number: LD2668 .T4 1985 P32 / Master of Science
19

Comunidades de aves frugívoras e nectarívoras e disponibilidade de recursos em dois estádios sucessionais de regeneração de Mata Atlântica.

Silva, Bruna Gonçalves da 13 April 2012 (has links)
Made available in DSpace on 2016-06-02T19:26:21Z (GMT). No. of bitstreams: 1 SILVA_Bruna_2012.pdf: 2724610 bytes, checksum: fe28e8afc06ce2b8c55372a0dbc428ee (MD5) Previous issue date: 2012-04-13 / The availability of food resources in different degrees of regeneration of a forest may contribute to possible variations in species abundance and composition of bird communities. The main objective of this study is to investigate the relationship between the structure of frugivores and nectarivores bird communities and the availability of food resources - flowers and fruit - in two successional stages of regeneration (initial-secondary and advanced) of the Atlantic Forest. To reach this goal, frugivores and nectarivores birds were monitored in representative sites of these stages, considering seasonality and production of flowers and fruits at each stage over a year. The frugivores and nectarivores were compared in richness, species composition, relative abundance and diversity. We used fixed point counts for sampling birds, and to estimate the production of flowers and fruits, we delimited three replicates of four plots (10x10m) at each stage of succession. The two studied successional stages differed significantly in most of the analyzed vegetation structure variables. The composition and relative abundance of some bird species also showed differences between the two stages of regeneration, but not quantitative parameters as richness and diversity. There were variations in plant community phenological curves and in the amount of the floral production between the two successional stages. The relative abundance of frugivores had a significantly positive relationship with the amount of available ripe fruits. In the advanced stages, the relative abundance of nectarivores birds had a significantly positive relationship to the number of individuals of flowering epiphytic plant species; while in secondary stages of regeneration there was no change in the abundance of nectarivores birds in response to floral resource availability. Thus, in areas that are not continuous to primary forests may occur in a declining population of frugivorous and nectarivorous birds in response to variations in the phenological curves and food shortages causing changes in the processes of breeding and selection of plant species, which can bring significant implications for the conservation of birds and plants. / A disponibilidade de recursos alimentares em diferentes graus de regeneração de uma floresta pode contribuir para possíveis variações na abundância de espécies e na composição da comunidade de aves. O objetivo principal deste estudo é investigar a relação entre a estrutura das comunidades de aves frugívoras e nectarívoras e a disponibilidade de recursos alimentares flores e frutos em dois estádios sucessionais - secundário-inicial e avançado - de regeneração de Mata Atlântica. Para isso, a avifauna frugívora e nectarívora foi monitorada em áreas representativas desses estádios, tendo sido considerada a sazonalidade e a produção de flores e frutos em cada estádio ao longo de um ano. Os frugívoros e nectarívoros das duas comunidades foram comparados em relação à riqueza, composição de espécies, abundância relativa e diversidade. Foi utilizado o método de pontos fixos para a amostragem da avifauna e, para estimar a produção de flores e frutos, foram demarcadas três repetições de quatro parcelas (10x10m) em cada estádio de sucessão. Os dois estádios sucessionais estudados diferiram significativamente na maioria das variáveis de estrutura da vegetação analisadas. A composição e abundância relativa de algumas espécies de aves também apresentaram diferenças entre os estádios de regeneração, mas não nos parâmetros quantitativos considerados para as avifaunas como a riqueza e diversidade. Houve variações nas curvas fenológicas da comunidade vegetal e na quantidade de recurso floral produzido entre os dois estádios sucessionais. A abundância relativa de aves frugívoras teve uma relação significativamente positiva com a quantidade de frutos maduros produzidos. As aves nectarívoras, em estádios avançados, tiveram uma relação significativamente positiva de sua abundância relativa com o número de indivíduos de espécies vegetais epífitas em floração, enquanto que em estádios secundários de regeneração não houve alteração na abundância das aves nectarívoras em resposta a disponibilidade de recursos florais. Assim, em áreas que não são contínuas a matas primárias pode ocorrer um declínio na população de aves frugívoras e nectarívoras em resposta a variações nas curvas fenológicas e escassez de alimento gerando alterações nos processos de reprodução e seleção de espécies de plantas, o que pode trazer implicações significativas para a conservação de aves e plantas.
20

Interações entre o morcego Sturnira lilium (Chiroptera: Phyllostomidae) e plantas da família Solanaceae / Interactions between the bat Sturnira lilium (Chiroptera: Phyllostomidae) and plants of the family Solanaceae

Mello, Marco Aurelio Ribeiro de 26 July 2006 (has links)
Orientadores: Wesley Rodrigues Silva, Elisabeth Klara Viktoria Kalko / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T07:15:46Z (GMT). No. of bitstreams: 1 Mello_MarcoAurelioRibeirode_D.pdf: 11924484 bytes, checksum: 489faee696e90bc83417a8122a4ef478 (MD5) Previous issue date: 2006 / Resumo: Morcegos têm grande importância ecológica nos Neotrópicos, por serem muito diversos, abundantes e interagirem com várias espécies de plantas e animais. Os morcegos filostomídeos da subfamília Stenodermatinae são frugívoros especializados e importantes dispersores de sementes, sendo que Sturnira lilium tem preferência por frutos de Solanaceae, uma família de grande valor ecológico e econômico. O objetivo do presente estudo foi investigar quatro aspectos principais e testar hipóteses relacionadas à maneira como essa interação ocorre e afeta ambos os grupos. De acordo com o esperado, a dieta de S. lilium foi inteiramente frugívora com uma forte dominância de solanáceas. A abundância de morcegos apresentou dois picos curtos ao longo do ano, ao contrário da produção de frutos que teve um pico único, porém mais longo. Os morcegos deixaram a área durante os meses mais frios e provavelmente migraram para altitudes mais baixas e quentes para escapar do clima severo e procurar por frutos de Solanaceae. A maioria das fêmeas de S. lilium se reproduziu durante os meses mais úmidos e quentes, durante a maior oferta de frutos. As solanáceas mostraram ser uma fonte de alimento confiável para S. lilium e sua fenologia pareceu regular a dinâmica populacional dos morcegos. S. lilium não apresentou fidelidade aos refúgios noturnos e diurnos, e usou uma grande distância de comutação e uma grande área de forrageio em comparação com outros pequenos mamíferos. A dispersão de sementes por S. lilium pareceu ser altamente benéfica para as plantas, de acordo com as hipóteses clássicas de fuga, colonização e dispersão limitada. Não observei evidências de fobia lunar em S. lilium, apesar de ter observado em outros dois filostomídeos frugívoros, Artibeus lituratus e Carollia perspicillata. As diferenças nas respostas à luz da Lua podem ser explicadas pelo habitat de forrageio, a dieta e distribuição espaço-temporal das plantas-alimento, e podem ter conseqüência para o sucesso reprodutivo das plantas-alimento. Os resultados do presente trabalho confirmam que a relação entre S. lilium e as solanáceas é muito forte, e que ela também é benéfica para ambos os grupos, afetando as populações de morcegos e plantas e consequentemente a estrutura de toda a comunidade / Abstract: Bats have a high ecological importance in the Neotropics for they are highly diverse, very abundant and interact with many plant and animal species. Phyllostomid bats of the subfamily Stenodermatinae are specialized frugivores and important seed dispersers, and Sturnira lilium prefers fruits of the Solanaceae, a family of high ecological and economical value. The goal of the present study was to investigate four main aspects and test hypotheses related to the way this interaction occurs and how it affects both groups. As expected, the diet of S. lilium was totally frugivore and Solanaceae prevailed. Bat abundance presented two short peaks throughout the year, while fruit production presented a single, but longer, peak. Bats left the area during colder months and probably migrated to lower and warmer altitudes to escape the severe climate and to search for Solanaceae fruits. Most S. lilium females reproduced during wetter and warmer months, during the highest fruit availability. The Solanaceae showed to be a reliable food source for S. lilium, and their phenology seemed to regulate bat population dynamics. S. lilium showed no roost fidelity, and used large commuting distances and foraging areas, if compared to other small mammals. Seed dispersal by S. lilium seemed to be highly beneficial for plants, according to the classical hypotheses of escape, colonization and limited dispersal. I observed no evidences of lunar phobia in S. lilium, despite having observed in other two frugivorous phyllostomids, Artibeus lituratus and Carollia perspicillata. Differences in response to moonlight may be explained by foraging habitat, diet and spatio-temporal distribution of food-plants, and may have consequences for the reproductive success of food-plants. Results of the present study suggest that the relationship between S. lilium and the Solanaceae is very strong, and that it is also beneficial for both groups, affecting populations of bats and plants, and consequently the structure of the whole community / Doutorado / Doutor em Ecologia

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