01. Universidade Federal Rural de Pernambuco - UFRPE (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/1
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Resultados da Pesquisa
Item Avaliação da estrutura populacional dos elasmobrânquios em um ecossistema insular no Oceano Atlântico Equatorial(2024-03-08) Rocha, Geremias Anacleto Lira da; Oliveira, Paulo Guilherme Vasconcelos de; Bezerra, Natalia Priscila Alves; http://lattes.cnpq.br/5613525779232672; http://lattes.cnpq.br/5700488412022830; http://lattes.cnpq.br/7804455435101278Observation per unit effort (OPUE) data were utilized to assess the population structure of elasmobranchs comprising the fauna of the São Pedro and São Paulo Archipelago (SPSPA) in the Equatorial Atlantic Ocean based on sightings during the period from 2008 to 2019. In this context, the overall objective of the study was to provide information about the population structure of elasmobranchs in the SPSPA fauna through sightings obtained during visual censuses in the region, aiming to contribute to the conservation of the island ecosystem and the species inhabiting the area. Throughout the study, 904 individuals were sighted during a sampling effort of 767 hours and 2 minutes of observation across 52 expeditions to the SPSPA. Rays represented 96.2% of the observations, with Mobula tarapacana being the most representative species (95.75%, n=833), followed by Mobula thurstoni (4.02%, n=35), and Mobula mobular (0.23%, n=2). Sharks accounted for 3.76% of the observations, exclusively belonging to the Carcharhinidae family, represented by the species Carcharhinus galapagensis (97.06%, n=33) and Carcharhinus falciformis (2.94%, n=1). Out of the total individuals sighted, the sex of 304 specimens was identified, with 188 being females, namely: 182 M. tarapacana, 1 M. thurstoni, and 5 C. galapagensis. For males, 116 individuals were identified, including 111 M. tarapacana, 4 M. thurstoni, and 1 C. galapagensis. Consistent variations in OPUE for the years and months of sampling indicate a trend in the occurrence of elasmobranch species in the SPSPA, with the highest annual values occurring in 2010 and 2015, and monthly values being prominent between February and August. According to IUCN criteria, only the Galapagos shark is not considered threatened with extinction in this study. Understanding the population structure of elasmobranchs is crucial for the management and conservation of species in the SPSPA, thereby contributing to the development of strategies to better understand the status of their populations and reduce their interaction with fishing activities.Item Aspectos reprodutivos e caracterização dos otólitos do agulhão Tylosurus acus acus (Lacepède, 1803) no Arquipélago de São Pedro e São Paulo, Brasil(2022-05-27) Falcão, Alice Cabral Delgado; Oliveira, Paulo Guilherme Vasconcelos de; Bezerra, Natália Priscila Alves; http://lattes.cnpq.br/5613525779232672; http://lattes.cnpq.br/5700488412022830; http://lattes.cnpq.br/3782971920533955The sailfish Tylosurus acus acus is a subspecies of belonid resident and abundant in the São Pedro and São Paulo archipelagos, for which there are no documented data on its biology throughout the South Atlantic Ocean. Reproduction and characterization of otoliths are important aspects to be studied, and unknown for T. acus acus. This study will provide the first information on the biology and characterization of otoliths of this species. From March 2019 to March 2020, 120 gonads were collected, measured, weighed, and used for the reproductive study, while 101 pairs of otoliths were collected. Gonads were classified macroscopically according to the Brown-Peterson scale. The ratio of gonads to each other was proposed by Schaeffer (1956). Mean length at sexual maturity was calculated using the relative frequency of adults per length class. Morphological characters were rostrum, antirostrum, acoustic sulcus, ostium, tail, and margins. The measures used for the calculated heights were morphometric measurements, length, and weight of the otolith, which were correlated with each other and with length. The observed sex ratio was 3.4F:1M, which could be due to sex separation. The monthly distribution of the proportion of maturation periods indicates that the site is likely a breeding area for the species. Abiotic and biotic factors, especially temperature, are essential for biological changes in the species. Correlations between high individuals suggest that measures of growth together and how they grow, as well as otolith changes. The information obtained in this study may contribute to the conservation of the Atlantic Ocean.Item Imagens subaquáticas geradas pelas Estações Remotas de Vídeo Subaquáticas com Isca (BRUVS) no Arquipélago de São Pedro e São Paulo(2021-12-14) Bezerra, Natalia Priscila Alves; Oliveira, Paulo Guilherme Vasconcelos de; http://lattes.cnpq.br/5700488412022830; http://lattes.cnpq.br/5613525779232672Item Biologia reprodutiva do bonito-listrado, Katsuwonus pelamis (Perciformes: Scombridae), no Arquipélago de São Pedro e São Paulo, Brasil(2021-03-05) Xavier, Victória Sincorá; Hazin, Fábio Hissa Vieira; Bezerra, Natalia Priscila Alves; http://lattes.cnpq.br/5613525779232672; http://lattes.cnpq.br/2479583060761727; http://lattes.cnpq.br/3068003817335469Item Estrutura populacional e influência ambiental na abundância de tubarões-baleia (Rhincodon typus Smith 1828) no Arquipélago de São Pedro e São Paulo, Brasil(2021-08-06) Veloso, João Vitor Albuquerque; Oliveira, Paulo Guilherme Vasconcelos de; Rocha, Bruno César Luz Macena; http://lattes.cnpq.br/9328544763622285; http://lattes.cnpq.br/5700488412022830; http://lattes.cnpq.br/8258401973123405Saint Peter and Saint Paul´s Archipelago (SPSPA) is an important site of Whale shark observations in Brazil as it has the highest frequency of sightings knows in the country. In the present work, data from sightings during scientific expeditions carried out between 2005 and 2018 (13 years) were computed and analyzed. Information on sightings was grouped by month, calculating the relative monthly frequency which was then compared with the environmental variables (temperature and chlorophyll a) obtained by remote sensing, with the objective of inferring their influence on the frequency of occurrence of the species in the archipelago. Photos and videos of the whale sharks were also collected. The images that presented satisfactory quality were processed using the semi-automated program called I³S (Interactive Individual Identification System). The results obtained so far are of great importance for the understanding of population structure, behavioral, feeding habits and migratory movements of the whale shark in the Atlantic Ocean, as they strengthen the hypothesis that sightings may be related to environmental variables such as sea surface temperature (SST) and chlorophyll-a concentration, including a possible loyalty to the archipelago since by photo-indentification we confirmed five re-sightings, three within a few days each other, one with about a year and an individual re-visited three times in different years.