En el marc d'un projecte més ampli sobre la comunitat de peixos de la conca lacustre de Banyoles, s'ha estudiat la distribució espacial de les diferents espècies així com l'ús que aquestes fan de l'hàbitat. El poblament piscícola de l'estany de Banyoles és el resultat d'un llarg historial d'introducció d'espècies exòtiques i extinció de les poblacions autòctones locals. S'ha revisat la seva composició actual detectant un total de 18 espècies (4 autòctones i 14 introduïdes) de les quals només 13 presenten una població estable.L'estudi de l'hàbitat s'ha centrat a l'Estany, l'element principal del sistema lacustre, analitzant per separat la zona litoral i la zona limnètica. En el primer cas s'han realitzat les captures d'individus mitjançant pesca elèctrica des d'una embarcació adaptada per aquesta pràctica. La totalitat del litoral ha estat dividida en trams de característiques homogènies on s'han obtingut les captures per unitat d'esforç per cada espècie. El mostreig s'ha desenvolupat entre l'estiu de 1997 i la primavera del 2000 realitzant un total de 10 campanyes de pesca. Les espècies més abundants al litoral són la perca americana (Micropterus salmoides) i el peix sol (Lepomis gibbosus), essent també presents la perca (Perca fluviatilis), carpa (Cyprinus carpio) i el gardí (Scardinius erythrophthalmus). S'han capturat altres espècies com ara anguila (Anguilla anguilla), bagra (Squalius cephalus), sandra (Sander lucioperca), carpí (Carassius auratus) i madrilleta vera (Rutilus rutilus), però són molt menys abundants en nombre. S'ha examinat, per cadascuna de les espècies, si existeix selecció de l'hàbitat i en cas afirmatiu, quin és el preferent en base a la classificació del litoral en sis tipus de vegetació predominant. Les espècies més abundants, perca americana i peix sol, ocupen tots els hàbitats disponibles però amb una densitat diferent. La perca mostra també una clara selecció de l'hàbitat a favor de les zones molt estructurades amb abundant presència de jonca litoral. Carpa i gardí seleccionen els ambients més fondos amb major presència de matèria orgànica d'origen vegetal procedent del bogar. En general els individus ocupen les zones amb una densitat de vegetació intermèdia, majoritàriament zones de jonca a l'estiu i zones amb mansega a l'hivern, on troben refugi i els recursos tròfics necessaris. La perca americana, a més, presenta una elevada fidelitat a un mateix punt del litoral al llarg de la seva vida.La zona limnètica ha estat prospectada mensualment mitjançant ecosondació, realitzant transectes perpendiculars a l'eix principal de l'Estany, cobrint la seva totalitat. La composició d'espècies s'ha obtingut a partir de les captures fetes amb xarxes (tresmalls) amb periodicitat estacional. L'anàlisi geoestadística de la densitat de peixos ha permès descriure l'estructura espacial d'aquesta a partir dels variogrames, així com la seva variabilitat tant espacial com temporal, i obtenir els mapes de densitat. A l'hivern, la densitat de peixos a la zona limnètica assoleix els seus valors mínims i els individus es troben formant agregats dispersos, pels diferents estrats de fondària. A partir de la primavera la densitat augmenta, pel reclutament i la major freqüència d'individus que abandonen el litoral; la densitat esdevé més homogènia a les primer capes de fondària. A l'estiu la densitat és màxima i l'estrat més homogeni coincideix amb la posició de la termoclina. Aquest estructura varia en disminuir la temperatura i barrejar-se la columna d'aigua, tornant a la situació hivernal. La perca i la madrilleta vera són les espècies predominants en aquest ambient, juntament amb la carpa. La seva distribució no és homogènia i respon a les característiques limnològiques de les diferents cubetes de l'Estany. Una particularitat d'aquest, relacionada amb el seu origen càrstic, es la formació d'una ploma hidrotermal que afecta la distribució dels peixos, probablement en augmentar la terbolesa.S'ha integrat l'ús de l'hàbitat de les espècies que ocupen tant la zona limnètica com la litoral a partir del seguiment d'individus, concretament de perca i bagra. S'ha utilitzat un sistema automàtic de posicionament que estima la localització dels individus marcats amb transmissor de telemetria acústica. L'anàlisi dels desplaçaments mostra un rang superior per la bagra en comparació amb la perca. Ambdues espècies mostren una orientació en els seus desplaçaments. La perca ocupa el litoral a la nit i es desplaça a la zona limnètica de dia, amb un ritme d'activitat marcat per dos màxims coincidint amb la sortida i posta de sol; en canvi la bagra mostra una major activitat nocturna amb zones de repòs properes al litoral. S'ha estimat igualment els dominis vital de cada individu marcat. / Habitat use and spatial distribution patterns of fish community from Lake Banyoles has been studied. Fish assemblage of this lake is the result of a long history of fish introductions and its current state has been assessed showing a high diversity with 14 exotic species and 4 native species. This study has been focused in the Lake, the main element of Banyoles's karstic system. Fish were captured in the littoral zone using a electrofishing boat. The whole perimeter of the lake was divided in 43 transects or sample units where all the fish were captured, processed and, finally, released at the same position. Sampling was divided in ten campaigns, between summer 1997 and winter 1999. Largemouth bass (Micropterus salmoides) and pumpkinseed sunfish (Lepomis gibbosus) were the most abundant in littoral zone. Other catches correspond to perch (Perca fluviatilis), common carp (Cyprinus carpio) and rudd (Scardinius erythrophthalmus). Habitat selection was analysed using both, the Manly Index of selection and the analysis of variance. Results showed that juvenile of largemouth bass, pumpkinseed sunfish and perch present a positive selection of habitat were Schoenoplectus litoralis or Cladium mariscus are dominants. Common carp and rudd present selection of littoral zones with Typha. Habitat selection is related with structurally complex environments. Perch and largemouth bass show temporal variation in the habitat distribution and smaller sizes preferred the intermediate vegetation density. Large bass presented also a high site fidelity. Limnetic zone was prospected monthly from December 1997 until December 1999, using both echosounding and trammel nets. Different species were detected including perch (Perca fluviatilis), roach (Rutilus rutilus), common carp (Cyprinus carpio), chub (Squalius cephalus) and pikeperch (Sander lucioperca). Fish density was maximum in summer and minimum in autumn-winter. Spatial pattern was described using geostatistics. In winter, fish formed aggregates in the center of the lake; with the increasing of fish density, in summer, the spatial distribution became more homogeneous with a maximum located at the same depth than thermocline. Abundance of different species varied with depth and limnological characteristics of basins. Also, the development of a hydrothermal plume due to underwater inflow, increase the turbidity of different parts of the lake altering fish distribution which avoid the presence of sediments. In order to monitoring the movements of perch and chub, 14 individuals were tagged with ultrasonic transmitters. Movements were followed by means of an automatic system showing a partition of habitat use between littoral zone and limnetic zone. Chub describes a pattern of movements bigger than perch but both species presents a main orientation of paths according with basin morphology. Activity (measured as velocity of displacements) was maximum at dawn and dusk in perch, with a diurnal increase while chub activity can be considered nocturnal.

Thesis (MFor)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: The factors determining habitat selection of large herbivores, on a private wildlife reserve in semi-arid southeastern Zimbabwe, were investigated. Gross vegetative structure, herbaceous composition and topographic features thought to determine herbivore distribution were measured. Seasonal variation in resource distribution was considered, and research therefore extended over an entire year. Herbivore distribution and ecological niche separation was explained through several important environmental variables, and potential for inter-specific competition inferred. Additionally, predictive habitat suitability models were designed for each of the grazing species in the critical dry season. Herbivores showed a large degree of niche overlap in both the hotwet season and the cool-dry season, when food resources were more plentiful. Niche separation between grazers was pronounced in the hot-dry season. Herbivore distribution was associated most closely with distance to water, grass sward height, time since burn, woody plant density and by the presence of predominant grasses, these being Urochloa mossambicensis, Panicum maximum, Heteropogon contortus and Digitaria eriantha. Ecological separation of herbivores by the grasses P. maximum, H. contortus and D. eriantha was more indicative of associated environmental variables than feeding niche separation. A GIS-based analysis, using species presence data and quantitative coverages of environmental variables, produced maps of gradations of habitat suitability for grazing species during the dry season. Results of both analyses were integrated and gave a better understanding of ecological separation, and possible competitive interactions, among the large herbivore community on Malilangwe Estate. Recommendations were made based on the interpretation of findings, within the context of available management options. / AFRIKAANSE OPSOMMING: Die bepalende faktore van habitat seleksie by groot herbivore op ‘n privaat wildreservaat in semi-dorre suidoos Zimbabwe is ondersoek. Globale plantegroei stuktuur, kruidagtige samestelling en topografiese eienskappe wat glo herbivoor verspreiding bepaal, is gemeet. Seisoenale variasie in hulpbronverspreiding is in ag geneem en dus het navorsing oor ‘n hele jaar gestrek. Herbivoor verspreiding en ekologiese nisskeiding is verduidelik deur verskeie belangrike omgewingsveranderlikes en die potensiaal vir interspesifieke kompetisie is afgelei. Boonop is voorspellende habitat-geskiktheidsmodelle ontwerp vir elk van die weidingspesies in die krities droë seisoen. Herbivore toon ‘n hoë graad van nis oorvleueling in sowel die warm, nat seisoen as die koel, droë seisoen wanneer voedingsbronne meer volop is. Nis verdeling tussen weidiere was duidelik herkenbaar in die warm, droë seisoen. Herbivoor verspreiding is meestal geassosieer met die afstand na die water, die grasveld hoogte, tydperk sedert ‘n brand, digtheid van houtagtige plantsoorte en met die teenwoordigheid van die oorheersende grasse, Urochloa mossambicensis, Panicum maximum, Heteropogon contortus en Digitaria eriantha. Die ekologiese skeiding van herbivore deur die grasse P. maximum, H. contortus en D. eriantha het meer gedui op geassosieerde omgewingsveranderlikes as op skeiding van voedingsnisse. ‘n GIS-gebaseerde analise wat spesie-teenwoordigheidsdata en kwantitatiewe dekking van omgewingsveranderlikes gebruik, het klassifikasiekaarte geproduseer van habitatgeskiktheid vir weidiere tydens die droë seisoen. Resultate van beide analises is geïntegreer en het ‘n beter begrip van ekologiese skeiding en moontlike kompeterende interaksies tussen die groot herbivore gemeenskap op Malilangwe Estate tot gevolg gehad. Aanbevelings is gemaak, gebaseer op die interpretasie van bevindinge, binne die konteks van beskikbare bestuursopsies.

L’étude des mécanismes qui régissent le succès d’établissement et d’expansion des espèces exotiques apparait primordial pour l’appréhension de leurs potentiels impacts. Ce travail de thèse a pour objet d’étude la Perruche à collier \textit{Psittacula krameri}, un Psittacidé largement introduit en Europe. Les objectifs de ces travaux relèvent de l’étude des facteurs qui peuvent influencer le succès d’établissement de cette espèce en milieu urbain, par l’analyse de la sélection de l’habitat à l’étude des traits comportementaux. Les résultats montrent que la sélection de l’habitat est associée aux activités humaines, de par la préférence de l’espèce pour les zones urbanisées dans lesquelles l’espèce semble être attirée par les lumières artificielles et les espèces végétales exotiques. La comparaison de la sélection de l’habitat avec une espèce native en expansion, le Choucas des tours \textit{Corvus monedula}, a permis de montrer que la Perruche à collier est contrainte spatialement aux zones suburbaines tandis que le Choucas pourrait être capable de s’étendre aux zones les plus urbanisées. Une approche expérimentale et éthologique a mis en lumière le comportement agressif de la Perruche à collier et une monopolisation passive des ressources alimentaires, suggérant un avantage compétitif sur les espèces natives. L’ensemble des résultats de cette thèse laisse présager un potentiel de forte croissance démographique des populations et contribue aux connaissances nécessaires pour comprendre les mécanismes qui régissent l’établissement et le succès des espèces en expansion, native et exotique, tant au travers de l’étude spatiale que comportementale. / Identifying the mechanisms which may allow invasive species to establish and spread is not only a scientific question of interest but also a crucial knowledge to acquire for the management of these species. This thesis work focuses on the ring-necked parakeet, \textit{Psittacula krameri},, a Psittacine species widely introduced throughout Europe.This thesis aimed to study factors underlying the spatiotemporal distribution and which may explain the urban success of this species, from the analysis of habitat selection to behavioral traits. Results showed that habitat selection is closely related to anthropic activities, the species showing a clear preference for suburban zones and green urban areas in which the species seems to be attracted by artificial lights and exotic tree species. Using the Western jackdaw, a native range-expanding and co-occurring species, distribution modelling allowed to predict the potential future distribution and showed that, while the jackdaw may spatially expand in the more urbanized part of the city, the ring-necked parakeet may be restricted to suburban areas in the future. An ethological experiment highlighted the agonistic behavior of the ring-necked parakeet and a passive monopolization of resources, suggesting a competitive advantage over native species, exacerbated by temporal niche overlap and avoidance behavior by native species. This thesis suggests that parakeets have the potential to reach high numbers in urban areas and the overall findings provide further insight into the mechanisms allowing the establishment and spread of expanding species, native and exotic, through spatial and behavioral factors.

S'appuyant sur l'exemple du mouflon méditerranéen Ovis gmelini musimon × Ovis sp. et sur plusieurs échelles spatio-temporelles, nous avions pour objectifs dans cette étude de mieux comprendre comment ces animaux modulent leurs comportements dans l'espace et/ou dans le temps face à l'hétérogénéité et la dynamique de leur environnement et de leurs propres besoins. Une revue du régime alimentaire du mouflon au sein de son aire de répartition mondiale nous a permis de vérifier l'importance des graminées chez cette espèce tout en révélant l'étendue des variations de son comportement alimentaire. Proposant une approche originale pour mesurer indirectement la qualité de son habitat, nous avons aussi évalué les conséquences de la répartition hétérogène de ces ressources alimentaires sur la masse corporelle des mâles de la population du massif du Caroux-Espinouse (Hérault). C'est à partir d'un suivi par colliers GPS dans cette population que nous avons ensuite mis en évidence une sélection de l'habitat nettement divergente entre les sexes au printemps et en été. Ce processus comportemental s'organise alors en une hiérarchie de décisions. Les choix des femelles sont d'abord largement dictés par les conditions qui devraient assurer la survie de leur progéniture, tandis que les mâles se concentrent sur les habitats offrant les meilleures conditions d'alimentation et une bonne protection thermique en été. A fine échelle, nos travaux montrent de nettes modulations de ces choix et des relations fortes entre comportements spatiaux et temporels chez ce ruminant, lui permettant de faire face au compromis nourriture/couverture. Nous nous sommes aussi intéressés de près à l'influence des activités humaines sur le comportement de cette espèce. Nous montrons que la chasse a des conséquences plus importantes que le tourisme, avec des réponses durant les périodes risquées mais aussi quand le risque est moindre à l'échelle journalière, et des effets y compris dans un espace protégé. Dans un contexte de changements globaux et de pressions anthropiques accrues, la mise en évidence de l'influence de l'hétérogénéité de l'habitat, du climat, des activités humaines et de leurs dynamiques respectives sur le comportement d'un grand herbivore devrait aider à mieux cerner les relations entre ces espèces et leurs habitats et à améliorer leur gestion. / Using Mediterranean mouflon Ovis gmelini musimon × Ovis sp. as a case study and based on several spatio-temporal scales, we aimed at better understanding how animals' choices change in space and/or time according to environmental heterogeneity and dynamics, and to own needs. A review on mouflon's diet across its range at the world level allowed us to confirm the importance of grass for this species, but also to reveal the wide variation in its foraging behaviour. Using an original approach allowing an indirect measure of habitat quality, we also evaluated the consequences of the heterogeneous distribution of foraging resources on the body mass of rams from the population of the Caroux-Espinouse massif (southern France). Based on data from a GPS monitoring in this population, we revealed sex-specific habitat selection during spring and summer. This behavioural process results from a hierarchy of decisions. Females' choices are mostly driven by the conditions that should ensure lamb survival, whereas males select the habitats providing the best foraging conditions and high thermal cover during summer. At fine scale, choices concurrently varied in space and time allowing this ruminant to cope with the food/cover trade-off. We also focused on the influence of human activities on the behaviour of this species. We showed that hunting had more marked consequences than tourism, with responses during both high and low-risk periods at the daily scale, and a spill-over effect in a protected area. In a context of global changes and increasing human pressures, revealing the influence of habitat heterogeneity, climate, human activities and of their relative dynamics on the behaviour of a large herbivore may help to better grasp the relationships between these species and their habitats and to improve their management.

Orientador: Itamar Alves Martins / Banca: Luis Cesar Schiesari / Banca: Lilian Casatti / Resumo: Girinos são um importante componente de ecossistemas de água doce e, ao longo dos últimos trinta anos, vêm sendo utilizados como modelos para testar hipóteses em ecologia de comunidades. O conjunto de informações disponível atualmente sugere que a presença de predadores influencia a abundância e o uso de hábitat por girinos e, conseqüentemente, a estrutura da comunidade. O objetivo deste estudo foi determinar o uso de recursos e investigar a influência de predadores na distribuição espacial de espécies e na estrutura de comunidades de girinos. As principais questões deste estudo foram: 1) qual o papel dos fatores abióticos na estruturação de comunidades de girinos?; 2) qual o grau de sobreposição de nicho entre as espécies nos três principais eixos de recursos: tempo (ocorrência sazonal), alimento e espaço (hábitat)?; 3) os girinos apresentam um padrão de distribuição não-aleatório em relação aos predadores? As amostragens tiveram freqüência mensal com coletas simultâneas de girinos e insetos predadores. Na caracterização dos corpos d'água foram utilizados dez descritores ambientais. Para determinar as guildas de espécies com relação ao uso de hábitat e ocorrência mensal foi implementada, respectivamente, uma análise de agrupamento e de ordenação por escalonamentro multidimensional não métrico. Para investigar a associação entre a abundância de girinos e os gradientes ambientais foi usada uma análise de correspondência canônica. A partilha de recursos entre girinos foi analisada utilizando-se uma análise de sobreposição de nicho em conjunto com um modelo nulo, considerando como eixos de recursos a ocorrência mensal, ocorrência nas poças e os itens alimentares. A análise da co-ocorrência pareada de girinos e predadores foi efetuada utilizando-se... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Tadpoles are an important component of freshwater ecossystems and in the last thirty years has been used as model organisms to test hypothesis in community ecology. The data currently available suggest that the presence of predators influences the abundance and habitat use by tadpoles and, consequently the community structure. The aims of this study were to establish how tadpoles divide resources and to investigate the influence of predators on species distribution and on community structure of tadpoles. The main questions were: 1) What is the role of abiotic factors in the community structure?; 2) What is the extent of niche overlap among species, considering the three main resource axes: time (seasonal occurrence), diet items and space (macrohabitat)?; 3) Tadpoles exhibit a non-random distribution pattern in relation to predaceous insects? We conducted monthly samplings to collect tadpoles and predaceous insects. We also used 10 environmental descriptors to characterize the water bodies. To recognize species guilds in relation to habitat use and monthly occurrence, we employed respectively a cluster analysis and a n-MDS, respectively. To investigate the association between species abundance and environmental gradients we used a canonical correspondence analysis. The resource partitioning among tadpoles was analyzed using a null model, considering as recource axes monthly occurrence, pond occupancy and diet items. The pair-wise co-occurrence analysis between tadpoles and predaceous insects was carried out using a null model. Our main findings demonstrate that forest canopy cover and pond hydroperiod were the main factors influencing species abundance along water bodies sampled. There was a species sorting along these two environmental gradients, with species restricted to both ends of these continuums. There was a high overlap in seasonal occurence... (Complete abstract click electronic access below) / Mestre

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Historical Ecology unifies concepts in ecology, behavior and phylogeny. To determine the evolutionary context of reproductive characters within the Leptodactylus pentadactylus species group and also to explore questions such as predation and habitat selection, I described the reproductive ecology of two key species, L. labyrinthicus and L. syphax) (Anura, Leptodactylidae). Field observations and experiments (2004 2008) were carried out in areas of Cerrado in southeastern and central Brazil. I characterized the oviposition sites of the two species by comparing the ecological conditions of the egglaying sites with those of nearby random points. Experiments with tadpoles were also conducted to describe their diel pattern of activity, hiding behaviour and level of susceptibility to predation by free-ranging birds. I determined whether L. syphax clutches have trophic eggs (tadpole food) by quantifying the proportion of eggs/embryos in recent nests. I also tested whether tadpoles of both species could prey on eggs of heterospecific foam nests. Leptodactylus labyrinthicus (140 mm SVL) breeds in temporary or permanent pools in swamps while L. syphax (70 mm) occurs in rocky and seasonal streams. Both species lay their eggs embedded in a white foam nest built by the amplectant pair; males beat the female cloacal fluids with both legs moving from side to side. Their foam nests were found beside the water, usually in basins excavated by the adults. Both species probably do not distribute their nests randomly across the environment, but actively choose micro-habitats with particular conditions (e.g., sheltered, close to water) that may provide relative protection for eggs/nestling tadpoles against the main risks present in their breeding sites (e.g., drying, maggot s infestation). Oviposition site selection including flexible strategies on the choice of micro-habitats in response to spatial and temporal variations has been reported for several frog species. In contrast to L. labyrinthicus, the clutches of L. syphax do not have trophic eggs, because most (90%) of the eggs develop into tadpoles. In the experiments, birds (leaf-scrapers) ate all exposed tadpoles of L. labyrinthicus, but no tadpole in the treatment where they could hide. Hence, the use of diurnal shelters and nocturnal habits may protect the tadpoles from such visual predators. Tadpoles of L. labyrinthicus can prey on eggs from heterospecific foam nests, but those of L. syphax do not. If the L. pentadactylus species cluster is monophyletic, excavated basins and foam-beating in lateral motions may be possible derived traits that arose in the common ancestor of the whole group. However, large adults, carnivorous tadpoles, and trophic eggs appear to be congruent synapomorphies of a less inclusive group. Based on this possible association of derived traits, the major reproductive features (e.g., trophic eggs, tadpole morphology and behaviour) of species of the L. pentadactylus group could be inferred largely from the body size (SVL) of adults. / A Ecologia Histórica unifica conceitos em ecologia, comportamento e filogenia. Na presente tese, descrevi a ecologia reprodutiva de duas espécies-chave, L. labyrinthicus e L. syphax (Anura, Leptodactylidae), a fim de determinar o contexto evolutivo de caracteres reprodutivos no grupo de Leptodactylus pentadactylus e também explorar questões como a predação e seleção de hábitat. As observações de campo e experimentais (2004 2008) foram realizadas em áreas de Cerrado nas regiões central e sudeste do Brasil. As condições ecológicas dos sítios de oviposição foram caracterizadas em relação ao entorno (pontos aleatórios). Conduzi experimentos com girinos para descrever o horário de atividade, comportamento de refúgio e susceptibilidade à predação por aves. Para determinar se desovas de L. syphax possuem ovos tróficos (alimento para girinos), analisei a proporção de ovos/embriões em ninhos recentes. Testei se girinos de ambas as espécies conseguem predar ovos de ninhos de espuma heteroespecíficos. Leptodactylus labyrinthicus (140 mm tamanho) reproduz em poças temporárias ou permanentes em ambientes brejosos enquanto que L. syphax (70 mm) utiliza regatos rochosos e sazonais. Ambas as espécies depositam seus ovos em ninho de espuma formado pelo casal durante o amplexo; os machos batem a espuma com suas pernas/pés executando movimentos laterais na região cloacal da fêmea. Os ninhos foram encontrados próximos à água, geralmente em bacias escavadas pelos adultos. Essas espécies não distribuem seus ninhos aleatoriamente no ambiente e selecionam sítios de oviposição cujas condições particulares (e.g., em abrigos, próximos à água) provavelmente conferem proteção relativa contra os principais fatores de mortalidade de seus ovos/embriões (e.g., dessecação, predação por larvas de moscas). A seleção de micro-ambientes de desova envolvendo estratégias moduláveis em resposta a variações espaciais e temporais tem sido reportada para várias espécies de anuros em contextos ecológicos diversos. Em contraste a L. labyrinthicus, as desovas de L. syphax não possuem ovos tróficos, pois a maioria (90%) dos ovos se desenvolve. Nos experimentos, aves (sabiá-poca) predaram girinos expostos de L. labyrinthicus, mas nenhum girino foi consumido no tratamento em que eles podiam se esconder. Portanto, o hábito noturno e a utilização de refúgios diurnos devem proteger os girinos de tais predadores. Os girinos de L. labyrinthicus são capazes de predar ovos de ninhos de espuma heteroespecíficos, mas os de L. syphax não. Se o grupo de L. pentadactylus é monofilético, bacias escavadas e batimento da espuma em movimentos laterais podem ser possíveis derivações exclusivas do grupo. No entanto, adultos grandes, girinos carnívoros e desovas com ovos tróficos parecem representar sinapomorfias correlatas (evolução associada) de um subgrupo restrito. Com base nessa associação de caracteres, será possível predizer aspectos-chave da ecologia reprodutiva (e.g., ovos tróficos, girinos oófagos) das 19 espécies do grupo de L. pentadactylus com base no tamanho corporal (CRC) de adultos. / Doutor em Ecologia e Conservação de Recursos Naturais

Fundação de Amparo a Pesquisa do Estado de São Paulo / The oviposition site selection may influence both offspring development and female fitness. Females of the harvestman Bourguyia hamata exhibit maternal care and oviposit almost exclusively inside the epiphytic bromeliad Aechmea nudicaulis in the Cardoso Island, SP. In the present study, I examined whether the morphological structure of the individuals of A. nudicaulis influences B. hamata oviposition site selection in a sandy coastal forest at Cardoso Island, SP, Brazil. Data about the presence of the egg-batches inside the bromeliads, the length of the rosettes (which are tubular), the bromeliad angle in relation to the soil and the amount of debris inside the bromeliads were obtained along a 700 m transect from February 2005 to January 2006. Additionally, I used data collected in 2001 about water volume inside the rosettes, as well as the variation in the humidity inside bromeliads with long (30-32 mm) and short (18-20 mm) rosettes, as well as in the external environment. The frequency of egg-batches was greater in individuals with angles among 90º to 150º, for which the amount of debris accumulated inside the rosettes was smaller. Longer rosettes were preferred as oviposition site by the B. hamata females. Moreover, bromeliads with longer rosettes accumulated more water inside them, keeping the humidity variation inside the bromeliads lower than the external environment. Females of B. hamata selected a single bromeliad species and also chose morphological characteristics of A. nudicaulis individuals. Females oviposited predominantly in bromeliads that accumulate more water and have small amounts of debris inside the rosettes, probably because these characteristics may promote a more adequate microhabitat for offspring development. / A escolha do sítio de oviposição pode ter várias implicações no desenvolvimento da prole e na aptidão da fêmea. As fêmeas do opilião Bourguyia hamata exibem cuidado maternal e utilizam exclusivamente a bromélia Aechmea nudicaulis como sítio de oviposição na Ilha do Cardoso, SP. Neste estudo investigou-se se características arquiteturais de A. nudicaulis podem influenciar sua escolha como sítios de oviposição por B. hamata na restinga da Ilha do Cardoso, SP. Dados sobre a presença de desovas no interior das bromélias, o comprimento das rosetas (em forma tubular), o ângulo da inclinação das bromélias em relação ao solo e a quantidade de detritos acumulada no interior das bromélias foram obtidos ao longo de um transecto de 700 m entre fevereiro de 2005 a janeiro de 2006. Adicionalmente, foram usados dados coletados em 2001 sobre o volume de água no interior da roseta, assim como sobre a variação de umidade ao longo do dia no interior de bromélias grandes (30-32 mm) e pequenas (18-20 mm) e também no ambiente externo. A freqüência de desovas foi maior em indivíduos com inclinações entre 90º e 150º, para os quais a quantidade de detritos no interior da bromélia foi menor. Rosetas maiores foram mais usadas como sítio de oviposição por fêmeas de B. hamata. Além disso, bromélias maiores acumularam mais água no seu interior, de forma que a variação da umidade relativa foi menor dentro das bromélias grandes quando comparada com o ambiente externo. Fêmeas de B. hamata, além de escolherem apenas uma espécie de bromélia, conseguem acessar também características estruturais dos indivíduos de A. nudicaulis. As fêmeas ovipuseram predominantemente nos indivíduos que acumularam mais água e possuíam menos detritos nas rosetas, provavelmente porque essas características devem promover um microhabitat mais adequado para o desenvolvimento da prole. / Mestre em Ecologia e Conservação de Recursos Naturais

O mutum-do-sudeste é endêmico da Mata Atlântica de baixada e foi extinto de quase toda sua distribuição original devido ao desmatamento e a caça. Hoje é listado como ameaçado e a falta de conhecimento sobre sua ecologia dificulta o manejo da espécie. Este trabalho teve como objetivo estimar a densidade populacional do mutum-do-sudeste na Reserva Natural Vale (RNV) através do método de transecção linear. Os registros feitos durante as amostragens também foram utilizados para verificar a existência de seleção de habitat por meio da comparação de áreas onde a espécie foi registrada com áreas aleatórias onde nunca obtivemos registros. A estimativa populacional obtida mostrou a existência de uma razão sexual desviada em relação aos machos que parecia estar relacionada a diferenças de comportamento entre os sexos, devido aos poucos registros de fêmeas. Para confirmar nossos resultados, utilizamos dados de armadilhas fotográficas que foram utilizadas para estudar onças na reserva. Estes dados confirmaram um número maior de machos na população, porém menos acentuado do que o encontrado nos transectos, comprovando que o comportamento discreto das fêmeas afetou nossa amostragem. Combinando os dados dos dois métodos obtivemos a estimativa de 1.6 indivíduos/Km2. As análises de seleção de habitat confirmaram a relação positiva do mutum-do-sudeste com matas altas e sub-bosque denso, e mostraram que o mutum-do-sudeste tem menor probabilidade de ocorrência em áreas com abundância de árvores mortas em pé, troncos em decomposição e serapilheira profunda. Tal influencia negativa provavelmente se deve a aspectos relacionados à sua dieta e a baixa tolerância a habitats que sofreram distúrbio. As informações contidas neste trabalho servirão de base para guiar o manejo de populações selvagens e futuros projetos de reintrodução. Além disso, estudos futuros devem considerar as diferenças de comportamento entre os sexos para que os dados sejam analisados de forma correta, evitando assim, erros que podem afetar diretamente o manejo da espécie. / The Red-billed Curassow was formerly found throughout the lowland Brazilian Atlantic Forest but is now extinct across most of its former range due to habitat loss and hunting pressure. Althought classified as globally threatened, there is still a chronic lack of information on Red-billed Curassows\' biology hindering efforts to mitigate the impacts of anthropogenic threats. We investigated population size and habitat relations of Red-billed Curassows at Vale Nature Reserve (VNR) using line transect and presence/absence method. Line transects results showed a male skewed sex ratio that appeared to be related to different behavivour between sexes as we recorded a low number of females. To evaluate any bias in the estimates of sex ratio from line transect we used data from a camera trap survey designed to monitor jaguars at the reserve. Camera trap data confirmed the existence of a male skewed sex ratio in the population but less pronounced than the one found on line transects, showing that different behavior between sexes affected our estimates. Using the sex ratio calculated with camera trap data we were able to estimate 1.6 individuals/Km2. The habitat assessment showed a positive relation of the Red-billed Curassow with taller forests and dense undergrowth. The abundance of snags, decaying log and leaf litter depth, negatively influenced Red-billed Curassows\' occurrence and appear to be related to its mainly frugivorous diet and low tolerance to habitat disturbances. Our study provides critical baseline information about an important population of Red-billed Curassows and will serve to guide management strategies and future reintroduction attempts. It also reveals that survey efforts must take into account sexual differences in behaviour to increase the reliability of modeled estimates. Failing to take these considerations into account may lead to misleading inferences from data, and impact management strategies for a seriously threatened species.

Dusky kob Argyrosomus japonicus is a wide-ranging estuarine-dependent Sciaenid and an important fishery species throughout most of its distribution. It is one of South Africa’s most valuable coastal fishery species. High levels of juvenile exploitation in estuaries and ineffective management regulations have led to stock collapse, highlighting the need to better understand the spatial and temporal aspects of estuarine-dependency and multiple habitat use. Habitat connectivity is a critical property of estuarine-associated fishes and it therefore follows that knowledge of this link is fundamental in understanding population dynamics and the nursery role of estuarine and/or marine habitats. While dusky kob occur in both estuaries and nearshore coastal zones, limited information on connectivity among these habitats exists. The aim of this study is to assess the role of estuarine nursery habitats in the life cycle of the dusky kob by examining multiple habitat connectivity and determining the drivers associated with estuarine use. A total of 96 dusky kob (237–1280 mm total length) were tagged with acoustic transmitters in both the estuarine and marine environments of Algoa Bay, Eastern Cape, South Africa between May 2008 and September 2010. Their movements were monitored using a network of automated data-logging acoustic receivers deployed in the Sundays Estuary, seven neighbouring estuarine habitats, two commercial harbours and various sites within Algoa Bay. And more...

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