This thesis examines the biology, ecology and anthropogenic threats of Indo-Pacific bottlenose dolphins (Tursiops aduncus) off Zanzibar, Tanzania, based on research conducted and samples collected between 2000 and 2008. Distribution and occurrence are described based on incidental catches (bycatch) in gillnet fisheries. Biology and ecology are examined by ageing and studying the reproductive biology and stomach contents of collected specimens. The composition of organohalogen compounds is determined in blubber samples, and assessment and mitigation of bycatch are conducted using observers onboard fishing vessels. Fisheries bycatch data showed that Indo-Pacific bottlenose dolphins occur year round in all areas around Zanzibar. Sexual maturity was attained between 7 and 8 years and body length 190-200 cm in females and at 16 years and body length 213 cm in males. The gestation period was estimated to be 12.3 months, with calving occurring throughout the year, peaking November-March and with an interval of 2.7 years. The estimated pregnancy rate was between 0.10 and 0.58 depending on methods used. Stomach contents revealed a relatively large number of prey species, but that only a few small- and medium-sized neritic fish and cephalopods contribute substantially to the diet. Estimates of total annual bycatch were >9% which is not considered sustainable. An experiment showed that pingers can be a short term mitigation measure to reduce bycatch of dolphins in both drift- and bottom set gillnets. Methoxylated polybrominated diphenyl ethers (Meo-BDEs) were found at higher concentrations than anthropogenic organic pesticides (OCPs), with only traces of polychlorinated biphenyls (PCBs) detected. This study reveals the magnitude and apparent susceptibility of Indo-Pacific bottlenose dolphins off Zanzibar to anthropogenic threats, especially fisheries bycatch, and it is clear that immediate conservation and management measures are needed to reduce bycatch. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 4: Manuscript. Paper 5: Submitted.

Cownose rays are benthic, suction feeders whose foraging activities have been implicated in severe damage to commercial shellfish industries and seagrass habitat. With jaws highly modified for durophagy, it has been assumed that they are crushing specialists, feeding primarily upon hard molluscan prey. In addition, R. bonasus are believed to be highly migratory, transient residents of coastal inshore waters. However, minimal quantitative data exist regarding R. bonasus feeding or movement patterns in the Gulf of Mexico. Stomach contents from 50 cownose rays caught within the Charlotte Harbor estuary between July 2003 and July 2004 were analyzed using the index of relative importance (IRI). Crustaceans, polychaetes, and bivalves were the dominant groups present, with bivalves representing the smallest proportion of the three dominant groups. High dietary overlap was observed between sexes, size groups and seasons. Shoalmates exhibited significantly more similar diets to each other than to members of other shoals. Although currently believed to be a hard prey specialist, these results suggest the cownose ray may behave as an opportunistic generalist, consuming any readily available prey. Between July 2003 and November 2004, 21 cownose rays were tagged and tracked within Charlotte Harbor using passive acoustic telemetry. Residence time ranged between 1-102 days. No significant relationship was detected between activity patterns and tidal stage or time of day. Minimum convex polygons (MCP) and kernel utilization distributions (KUD) were calculated to demonstrate the extent of an animals home range and core areas of use. Daily MCPs ranged between 0.01 and 25.8 km2, and total MCPs ranged between 0.81 and 71.78 km2. Total 95% KUDs ranged between 0.18 and 62.44 km2, while total 50% KUDs were significantly smaller, ranging from 0.09 to 9.68 km2.

Diet and female feeding competition was examined within two groups of free-ranging ringtailed lemurs (Lemur catta) at the Beza Mahafaly Special Reserve in southwestern Madagascar. The first group’s home range was located within a protected gallery forest, the second is in a degraded forest and human-occupied area. The diets of the females were found to vary between groups; females fed on different plant species, and those in the unprotected area frequently consumed human food scraps and domestic animal fecal matter. Contest and scramble competition were detected within both groups. Rates of feeding competition were found to increase according to the type of food being consumed; feeding on fruits and leaves correlated with increased competition in the reserve group, and feeding on human foods and animal fecal matter correlated with increased competition with the non-reserve group. These dietary and competitive differences highlight the need for continued, and possibly additional, protection of L. catta in this region.

Diet and female feeding competition was examined within two groups of free-ranging ringtailed lemurs (Lemur catta) at the Beza Mahafaly Special Reserve in southwestern Madagascar. The first group’s home range was located within a protected gallery forest, the second is in a degraded forest and human-occupied area. The diets of the females were found to vary between groups; females fed on different plant species, and those in the unprotected area frequently consumed human food scraps and domestic animal fecal matter. Contest and scramble competition were detected within both groups. Rates of feeding competition were found to increase according to the type of food being consumed; feeding on fruits and leaves correlated with increased competition in the reserve group, and feeding on human foods and animal fecal matter correlated with increased competition with the non-reserve group. These dietary and competitive differences highlight the need for continued, and possibly additional, protection of L. catta in this region.

Made available in DSpace on 2015-04-17T14:55:24Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1822472 bytes, checksum: 029afda8692ebb7aa8994936007707fb (MD5) Previous issue date: 2012-07-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This study focused on the habitat use and foraging activity of juveniles and adults of the parrotfishes S. axillare and S. frondosum (Perciformes: Scarinae) at the Maracajaú Reefs, state of Rio Grande do Norte. The abundance of two species, habitat characteristics, and food availability were recorded along 60 transects (30 m X 2 m). Foraging activity was characterized by 409 direct observations, using "Animal-focal" and "All occurrences" methodologies. Aggregation and agonistic behaviors associated with foraging activity were also recorded. Canonical Correspondence Analysis (CCA) revealed differences in the spatial distribution of S. axillare and S. frondosum, and between different life phases. Juvenile parrotfishes exhibited the highest feeding rate (bites/minute) while adult S. frondosum terminal phase individuals showed the lowest number of bites. Juvenile and adult parrotfishes ate more frequently Mixed substrate and Sand, items containing large amounts of sediments and detritus in their composition. Feeding selectivity differed between S. axillare and S. frondosum, as well as in relation to life phases and food availability. Only 23% (n=95) of the individuals were sighted foraging in aggregations, mostly adult S. frondosum which formed large mixed schools, mainly with Scarus trispinosus and Acanthurus chirurgus. Attacks of Stegastes fuscus against parrotfishes constituted 76% of the agonistic behaviors recorded. / Este estudo teve como foco o uso do habitat e a atividade de forrageio de jovens e adultos dos budiões Sparisoma axillare e Sparisoma frondosum (Perciformes: Scarinae) nos recifes de Maracajaú, litoral do Rio Grande do Norte. A abundância das duas espécies, as características do habitat e a disponibilidade de itens alimentares foram registradas ao longo de 60 transecções em faixas (30 m X 2 m). A atividade de forrageio foi caracterizada através de 409 observações diretas, utilizando-se os métodos Animalfocal e Todas as ocorrências . Comportamentos de agregação e agonísticos realizados durante a atividade de forrageio também foram registrados. Através da Análise de Correspondência Canônica (CCA) observou-se uma distribuição espacial diferenciada entre S. axillare e S. frondosum, bem como entre suas fases de vida. Jovens de Sparisoma apresentaram a maior taxa de alimentação (mordidas/minuto), enquanto adultos de S. frondosum em fase terminal efetuaram o menor número de mordidas. Durante a alimentação, jovens e adultos de Sparisoma ingeriram com maior frequência os itens Substrato misto e Areia, caracterizados por conter grande quantidade de sedimento e detritos em sua composição. Ambas as espécies apresentaram seletividade ao alimentar-se; esta diferiu entre espécies, fases de vida e disponibilidade de alimento no ambiente. Apenas 23% (n =95) dos indivíduos foram avistados forrageando em agregações, sendo a maioria deles adultos de S. frondosum, que formavam grandes cardumes mistos, principalmente com Acanthurus chirurgus e Scarus trispinosus. Ataques de Stegastes fuscus contra Sparisoma constituíram 76% dos comportamentos agonísticos registrados.

Le régime alimentaire est un élément clé de l’écologie des espèces et dépend à la fois des besoins nutritionnels des individus et des ressources alimentaires disponibles. Ainsi, les stratégies alimentaires peuvent varier en fonction de l’âge, du sexe ou de l’état physiologique des individus, mais également de paramètres environnementaux et, en particulier, de la saisonnalité. Reconstruire le régime alimentaire d’espèces cryptiques ou difficiles à observer en milieu naturel nécessite l’emploi de marqueurs capables de détecter les variations du régime alimentaire sur le court terme. L’analyse des patrons de micro-usures dentaires et des ratios d’isotopes stables du carbone et de l’azote constitue une approche pertinente pour distinguer le régime alimentaire entre différentes espèces ou entre populations. Dans le cadre de cette thèse, nous avons évalué le pouvoir prédictif de ces deux types de marqueurs sur les variations saisonnières et interindividuelles du régime alimentaire dans une population naturelle de mandrills (Mandrillus sphinx) sur laquelle des données comportementales étaient disponibles. Conformément aux comportements alimentaires observés, les patrons de micro-usures dentaires et les signatures isotopiques varient en fonction de la saison, de l’âge et du sexe des individus. L’ensemble de nos résultats nous indique que la diversité importante d’aliments consommés à faible fréquence par les mandrills ne peut être détectée par les marqueurs analysés qui semblent être, en revanche, pertinents pour identifier des changements significatifs de consommation d’aliments majoritaires tels que les fruits et les feuilles. Enfin, les signatures isotopiques varient en fonction du cycle reproducteur des femelles et de leur rang de dominance, nous indiquant que l’utilisation de tels marqueurs peut permettre la mise en évidence d’aspects de la physiologie des individus non reportés par des observations comportementales. Les résultats présentés dans cette thèse apportent des données de référence essentielles pour la reconstruction du régime alimentaire d’espèces éteintes partageant des traits communs avec le mandrill, telles que des primates généralistes de forêts tropicales. / Diet is a critical factor of species’ ecology and depends on both individuals’ nutritional needs and availability of their food resources. As such, feeding strategies may vary with age, sex or physiological condition of the individuals but also depend on environmental factors and, in particular, seasonality. In cryptic species and those that are difficult to observe in their natural habitat, diet reconstruction requires the use of proxies with the ability to detect dietary variations over the short term. Analyses of dental microwear patterns along with carbon and nitrogen stable isotopes constitute a relevant approach to discriminate between diets of different species or populations. In the framework of this thesis, we assessed the predictive power of these two proxies on seasonal and inter-individual variations of diet in a natural population of mandrills (Mandrillus sphinx) for which behavioural data was available. According to the feeding behaviours observed, dental microwear patterns and isotopic signatures vary depending on the season as well as individual’s age and sex. Taken together our results indicate that the large diversity of rarely consumed food items cannot be detected by the proxies analysed, which are however, relevant to identify significant changes in the consumption of major foods such as fruits and leaves. Finally, isotopic signatures vary across females’ reproductive statuses and dominance ranks, indicating that the use of those proxies may allow the highlighting of some aspects of individuals’ physiology not detected by behavioural observations. The results presented in this thesis provide a baseline data essential for dietary reconstruction of extinct species sharing similar traits with mandrills, such as generalist primates from tropical forests.

Este estudo apresenta dados sobre a ecologia alimentar do gavião-do-rabo-branco (Buteo albicaudatus albicaudatus) no município de Juiz de Fora, sudeste do estado de Minas Gerais. Os objetivos específicos foram: a) estudar quantitativamente a dieta do gavião-do-rabo-branco, incluindo número de presas e biomassa consumida; b) analisar possíveis padrões de sazonalidade na dieta; c) determinar a amplitude de nicho trófico do gavião-do-rabo-branco; d) verificar a existência de possíveis respostas numéricas e funcionais na dieta desse gavião e e) verificar estatisticamente as prévias proposições de oportunismo na escolha de presas por esse predador sugeridas por Stevenson & Meitzen (1946), Farquhar (1986) e Kopeny (1988). O material para estudo da dieta do B. albicaudatus consistiu de pelotas de regurgitação, coletado simultaneamente com os dados de abundância dos principais grupos de presas e do predador na área de estudo. As 259 amostras analisadas revelaram 31 espécies/morfoespécies e uma biomassa total estimada de 7196,5 g. Cinco ordens de insetos (Hymenoptera, Heteroptera, Odonata, Isoptera e Lepidoptera) e uma de vertebrado (Chiroptera) são descritas pela primeira vez como integrantes da dieta de B. albicaudatus. Numericamente, os invertebrados representaram 88% da dieta, sendo Acrididae responsável por 63% da dieta total. Dentre os vertebrados, os roedores foram o grupo mais consumido (73% da classe e 8% da dieta total). Analisando-se as presas em relação à biomassa, verificou-se uma brusca inversão na maioria das espécies/morfoespécies. Nesta abordagem, os vertebrados corresponderam a 77% da dieta. Os grupos mais representativos são: roedores (50%), ortópteros (21%), aves (11%), lagartos (7%) e serpentes (5%). A análise de sazonalidade na dieta mostrou uma evidente dependência de consumo quanto à estação climática, em mais da metade das categorias. Na estação seca verifica-se um maior consumo de Araneomorphae, outros artrópodes e mamíferos, enquanto na estação chuvosa, o maior consumo foi registrado para Acrididae e Coleoptera. Aves e répteis, apesar de não apresentarem uma dependência significativa em relação à sazonalidade, parecem ser utilizados como complemento ao consumo de mamíferos na estação chuvosa, no que tange a biomassa ingerida. Buteo albicaudatus pode ser classificado como insetívoro, em termos de número, ou como carnívoro, em termos de biomassa ingerida. A amplitude trófica da dieta mostrou-se de intermediária para baixa, variando de acordo com a abordagem adotada. Em termos gerais, quanto ao número e a biomassa, a dieta total mostrou que o gavião-do-rabo-branco é especialista. No entanto, a análise da biomassa referente a cada estação climática revelou que na estação chuvosa, a dieta é intermediária entre generalista e especialista (Bp itens=0,292; Bp grupos=0,485). Esses dados indicam que tanto o consumo de determinados itens alimentares quanto a amplitude de nicho trófico pode variar de acordo com a estação climática. Comparando-se a abundância do principal grupo de presa (pequenos mamíferos), em termos de biomassa, no ambiente e os registros de B. albicaudatus percebe-se que em nove dos doze meses há uma sincronia nas flutuações, caracterizando uma resposta numérica (rs=0,864; p<< 0,001). Resposta funcional foi registrada para a ordem Orthoptera (rs=0,762; p<0,01) e para a família Acrididae (rs=0,706; p<0,05). Com relação à seletividade de espécies de presas, observou-se que dos 12 gêneros de pequenos mamíferos capturados por armadilhas de interceptação e queda no ambiente, apenas cinco (Calomys, Akodon, Oligoryzomys, Oxymycterus e Gracilinanus) fazem parte da dieta de B. albicaudatus. Em relação a estes gêneros, o gavião-do-rabo-branco apresentou seletividade para Calomys tener e rejeição para Akodon spp apenas na estação seca. Os dados apresentados neste estudo sugerem que a abundância de pequenos mamíferos pode determinar o comportamento seletivo ou oportunismo de B. albicaudatus. No período de maior oferta de recurso há uma seletividade enquanto, no período de menor abundância de alimento, há um oportunismo por parte do predador. Este estudo revelou que o gavião-do-rabo-branco possui uma flexibilidade em sua dieta.

The combined methods of stomach content analysis and stable 15N and 13C isotope biochemistry analysis were used to investigate the trophic dynamics and feeding ecology of coastal pelagic fishes in the waters off southeastern Florida, USA. The coastal pelagic fish complex includes blackfin tuna Thunnus atlanticus, dolphinfish Coryphaena hippurus, king mackerel Scomberomorus cavalla, little tunny Euthynnus alletteratus, skipjack tuna Katsuwonus pelamis, and wahoo Acanthocybium solandri. These coastal teleosts, particularly the tunas and wahoo, are primarily targeted by recreational anglers. However, there is a shortage of available trophic and diet composition data concerning these fishes of the coastal pelagic ecosystem. Stomach and muscle tissue samples were collected from the species of various lengths over a three-year period from March 2010 and March 2013. Across all six species, teleost fishes dominated the prey with an average 64.5% by occurrence, 63.7% by number, and 89.9% by weight. There were two dominant prey families: Clupeidae and Carangidae. Dolphinfish showed the lowest diet overlap among the six species, due to the highly diverse diet. The highest diet overlap occurred between king mackerel and little tunny. The mean δ15N ranged from 8.21 ‰ (wahoo) to 13.18 ‰ (king mackerel), and the mean δ13C ranged from -18.41 ‰ (king mackerel) to -16.70 ‰ (dolphinfish). Blackfin tuna exhibited the largest δ15N range (7.22 to 13.21 ‰), as well as the largest δ13C range (-19.13 to -12.99 ‰). The δ15N and δ13C signatures in the muscle tissue showed evidence of shifts to higher trophic levels with an increase in fish size and the formation of distinct trophic groups among the coastal pelagic predators. The δ13C also suggested an inshore-offshore spatial relationship among the coastal pelagic fish. The trophic dynamics and feeding ecology data generated by this study will provide valuable baseline data for the coastal pelagic complex and future ecosystem studies.

This project was initiated in an attempt to address the paucity of data on Asiatic black bears (Ursus thibetanus) in Mainland China. Field work was carried out from May 2004 – August 2006 within the Tangjiahe National Nature Reserve in northwestern Sichuan Province, China. Initial methodology relied on trapping and GPS radio-collaring bears, but due to extreme difficulty with capturing a sufficient sample size, I expanded the study to include reproduction, feeding analysis from scats and sign, and occupancy modeling from sign surveys. I documented the home ranges of an adult female (100% MCP = 107.5km2, n=470 locations) and a sub-adult female (100%MCP = 5.9km2, n=36 locations) Asiatic black bear. I also documented two birthing occasions with a total of four male cubs produced and eight bear den sites. I collected feeding data from 131 scat samples and 200 bear sign transects resulting in 50 identified food items consumed by Asiatic black bears. I also employed the program PRESENCE to analyze occupancy data using both a standard grid repeated sampling technique and an innovative technique of aging bear sign along strip transect surveys to represent repeated bear occupancy over time. Conservation protection patrolling and soft mast were shown to be the most important factors determining the occupancy of an area by Asiatic black bears in Tangjiahe Nature Reserve, Sichuan Province, China. / Master of Science

[pt] Neste estudo foram determinadas as concentrações de Se e Hg, no tecido hepático, muscular e renal, de 70 golfinhos de cinco espécies diferentes (Tursiops truncatus, Stenella frontalis, Steno bredanensis, Sotalia guianensis e Pontoporia blainvillei) e uma espécie de ave marinha (Sula leucogaster), encontrados mortos, durante os anos de 2001 e 2013, na Costa Centro-Norte fluminense. A fim de identificar o processo de bioacumulação e biomagnificação, foram determinadas as concentrações de Se e Hg no fígado e no músculo de cinco espécies de peixe (Trichiurus lepturus, Micropogonias furnieri, Mugil liza, Sardinella brasiliensis, Scomber japonicus) e um cefalópode (Loligo plei). Para auxiliar no estudo dos níveis de Se e Hg, também foram avaliados os valores dos isótopos estáveis Delta 13C e Delta 15N no músculo de todas as espécies envolvidas. As concentrações mais elevadas de mercúrio e selênio foram observadas no fígado dos golfinhos, que apresentaram valores entre 11,2 e 684 mg kg elevado a potência negativa 1 para o Hg e entre 10,2 e 111 mg kg elevado a potência negativa 1 para Se. No músculo foram observadas concentrações mais baixas de Se e Hg nos golfinhos, apresentando concentrações de Hg que variaram entre 1,8 a 9,8 mg kg elevado a potência negativa 1, e de Se que variaram entre 1,9 a 2,3 mg kg elevado a potência negativa 1. A concentração de Hg no rim variou de 1,5 a 22 mg kg elevado a potência negativa 1 e de Se entre 7,6 a 12 mg kg elevado a potência negativa 1 nos golfinhos. Entre as presas, as concentrações mais elevadas de Hg e Se foram observadas no fígado, o mercúrio variou entre 0,3 e 1,6 mg kg elevado a potência negativa 1 e o selênio entre 6,6 e 40,4 mg elevado a potência negativa 1. As concentrações de Hg muscular ficaram entre 0,45 e 0,046 mg kg elevado a potência negativa 1 e de Se muscular entre 2,3 e 1,4 mg kg elevado a potência negativa 1 nas presas. Os golfinhos apresentaram maior enriquecimento de nitrogênio com valores médios entre 14,0 e 17,5 por mil. Para os isótopos estáveis de carbono, os valores médios variaram entre menos 16,8 e menos 15,5 por mil nos cetáceos. A razão isotópica entre as presas varou entre 8,3 e 13,5 por mil para o Delta 15N e entre menos 18,3 a menos 11,9 para o Delta 13C. Foi observado poder de biomagnificação positivo para o mercúrio nas espécies S. guianenis (log [Hg] = menos 0,031 mais 0,195 asterisco Delta 15 N; r igual a 0,719; p menor 0,001) e S. frontalis (log [Hg] igual a menos 0,15 mais 0,21 asterisco Delta 15 N; r igual 0,68; p menor que 0,0001), sendo possível concluir que a biomagnificação do Hg é efetiva na região estudada. / [en] This study determined the concentrations of Se and Hg in the liver, muscle and kidney tissue, of 70 dolphins from five different species (Tursiops truncatus, Stenella frontalis, Steno bredanensis, Sotalia guianensis and Pontoporia blainvillei) and a species of seabird (Sula leucogaster), found dead during 2001 and 2013 on the North-Central Coast of the State of Rio de Janeiro. In order to identify the bioaccumulation and biomagnification processes, the concentrations of Se and Hg in the liver and muscle of five species of fish (Trichiurus lepturus, Micropogonias furnieri, Mugil liza, Sardinella brasiliensis, Scomber japonicus) and a cephalopods (Loligo plei) were determined. To assist in the study of Se and Hg, Delta 13 C and Delta 15 N stable isotopes in the muscle of all investigated were also evaluated species involved. The highest concentrations of mercury and selenium were observed in dolphin liver, which presented values between 11.2 and 684 mg kg elevated to negative power 1 for Hg and between 10.2 and 111.3 mg kg elevated to negative power 1 for Se. In muscle lower concentrations of Se and Hg were observed for these species, showing Hg concentrations ranging from 1.8 to 9.8 mg Kg elevated to negative power 1, while Se ranged from 1.9 to 2.3 mg kg elevated to negative power 1. Hg concentrations in the kidney varied from 1.5 to 22.0 mg kg elevated to negative power 1 and Se between 7.6 to 12.2 mg kg elevated to negative power 1 in dolphins. Among the prey, higher concentrations of Hg and Se were observed in liver, mercury varied from 0.28 to 1.6 mg kg elevated to negative power 1 and selenium between 6.6 and 40.4 mg kg elevated to negative power 1. Hg muscle concentrations were between 0.45 and 0.046 mg kg elevated to negative power 1 and muscle Se between 2.3 and 1.4 mg kg elevated to negative power 1 in the prey. Dolphins show higher nitrogen enrichment with mean values between 14.0 and 17.5 per thousand. For the stable carbon isotopes, the mean values ranged between less 16.8 and less 15.5 per thousand in cetaceans. The isotopic ratio of the prey ranged between 8.3 and 13.5 per thousand for Delta 15N and between less 18.3 and less 11.9 for Delta 13C. Positive biomagnification power was observed for mercury to species S. guianenis (log [Hg] equal less 0.031 more 0.195 asterisk Delta 15N; r equal 0.719; p less than 0.001) and S. frontalis (log [Hg] equal less 0.15 more 0.21 asterisk Delta 15N; r 10 equal 0.68; p less than 0.0001), and indicating that the biomagnification of Hg is effective in the region studied.