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

When wolves cry: long distance calling by wild maned wolves

Rocha, Luciana Helena Silva 25 May 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-25T23:08:58Z No. of bitstreams: 1 LucianaHelenaSilvaRocha_DISSERT.pdf: 1669201 bytes, checksum: 3c7d0a6a9b45e9896e7c8ea5f9fd7eef (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-27T23:53:09Z (GMT) No. of bitstreams: 1 LucianaHelenaSilvaRocha_DISSERT.pdf: 1669201 bytes, checksum: 3c7d0a6a9b45e9896e7c8ea5f9fd7eef (MD5) / Made available in DSpace on 2016-04-27T23:53:09Z (GMT). No. of bitstreams: 1 LucianaHelenaSilvaRocha_DISSERT.pdf: 1669201 bytes, checksum: 3c7d0a6a9b45e9896e7c8ea5f9fd7eef (MD5) Previous issue date: 2015-05-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O lobo-guar? (Chrysocyon brachyurus Illiger 1815) ? o maior can?deo da Am?rica do Sul e encontra-se quase-amea?ado de extin??o segundo a IUCN. Por ser uma esp?cie noturna, territorial e com h?bitos solit?rios, ainda h? muitos aspectos pouco estudados sobre seu comportamento em ambiente natural, entre eles a comunica??o ac?stica. Em seu repert?rio vocal, o lobo apresenta a vocaliza??o de longa-dist?ncia chamada de ?aulido? a qual, segundo a literatura, tem fun??o de manuten??o do espa?amento entre indiv?duos e/ou comunica??o entre os membros do par reprodutivo dentro do territ?rio. Nesse contexto, esse estudo teve como objetivos: 1) comparar quatro m?todos de detec??o dos aulidos de lobo-guar? em grava??es feitas em ambiente natural, buscando eleger o mais eficiente para nosso projeto; 2) entender como se d? o padr?o noturno de emiss?o dessas vocaliza??es, verificando se as condi??es clim?ticas e as fases da lua influenciam nas taxas de emiss?o de aulidos; e 3) testar o Monitoramento Ac?stico Passivo como ferramenta na identifica??o da presen?a de lobos-guar? em ambiente natural. A ?rea de estudo foi o Parque Nacional da Serra da Canastra (Minas Gerais, Brasil) e foram utilizados gravadores aut?nomos para aquisi??o dos sons, os quais gravaram durante toda a noite (18h-06h) durante cinco dias de dezembro/2013 e durante todos os dias dos meses de abril a julho/2014. Os m?todos de detec??o de aulidos foram testados e comparados com rela??o ao tempo necess?rio para analisar os arquivos, n?mero de falsos positivos e n?mero de aulidos corretamente identificados. O m?todo misto (XBAT+manual) foi o mais eficiente, encontrando 100% das vocaliza??es em quase metade do tempo do m?todo manual, e foi eleito para an?lise dos nossos dados. O estudo da varia??o temporal da emiss?o de aulidos verificou que os lobos vocalizam mais nas primeiras horas da noite, o que sugere uma fun??o social importante para esses chamados no in?cio de seu per?odo de atividade mais intenso. A velocidade m?dia do vento influenciou negativamente a frequ?ncia de vocaliza??es, o que pode indicar baixa recep??o sonora dos gravadores ou altera??o nos padr?es comportamentais dos lobos em condi??es de ventos fortes. ? necess?rio um melhor entendimento da varia??o sazonal da atividade vocal dos lobos-guar?, mas nosso estudo j? demonstra ser poss?vel detectar padr?es comportamentais de animais selvagens apenas atrav?s do som, validando o Monitoramento Ac?stico Passivo como ferramenta na conserva??o dessa esp?cie. / The maned wolf (Chrysocyon brachyurus Illiger 1815) is the biggest canid in South America and it is considered a ?near threatened? species by IUCN. Because of its nocturnal, territorial and solitary habits, there are still many understudied aspects of their behavior in natural environments, including acoustic communication. In its vocal repertoire, the wolf presents a longdistance call named ?roar-bark? which, according to literature, functions for spacing maintenance between individuals and/or communication between members of the reproductive pair inside the territory. In this context, this study aimed: 1) to compare four methods for detecting maned wolf?s roar-barks in recordings made in a natural environment, in order to elect the most efficient one for our project; 2) to understand the night emission pattern of these vocalizations, verifying possible weather and moon phases influences in roarbark?s emission rates; and 3) to test Passive Acoustic Monitoring as a tool to identify the presence of maned wolves in a natural environment. The study area was the Serra da Canastra National Park (Minas Gerais, Brazil), where autonomous recorders were used for sound acquisition, recording all night (from 06pm to 06am) during five days in December/2013 and every day from April to July/2014. Roar-barks? detection methods were tested and compared regarding time needed to analyze files, number of false positives and number of correctly identified calls. The mixed method (XBAT + manual) was the most efficient one, finding 100% of vocalizations in almost half of the time the manual method did, being chosen for our data analysis. By studying roarbarks? temporal variation we verified that the wolves vocalize more in the early hours of the evening, suggesting an important social function for those calls at the beginning of its period of most intense activity. Average wind speed negatively influenced vocalization rate, which may indicate lower sound reception of recorders or a change in behavioral patterns of wolves in high speed wind conditions. A better understanding of seasonal variation of maned wolves? vocal activity is required, but our study already shows that it is possible to detect behavioral patterns of wild animals only by sound, validating PAM as a tool in this species? conservation.
2

Ecologia ac?stica de pares f?mea-filhote de baleia franca austral (Eubalaena australis) (Desmoulins, 1822) em ?guas costeiras do estado de Santa Catarina, Brasil

Dombroski, J?lia Ribeiro Guimar?es 27 May 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T21:56:38Z No. of bitstreams: 1 JuliaRibeiroGuimaraesDombroski_DISSERT.pdf: 2747987 bytes, checksum: b210dc48f70ecb104f4b1aa36da3d312 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-14T00:37:51Z (GMT) No. of bitstreams: 1 JuliaRibeiroGuimaraesDombroski_DISSERT.pdf: 2747987 bytes, checksum: b210dc48f70ecb104f4b1aa36da3d312 (MD5) / Made available in DSpace on 2016-05-14T00:37:51Z (GMT). No. of bitstreams: 1 JuliaRibeiroGuimaraesDombroski_DISSERT.pdf: 2747987 bytes, checksum: b210dc48f70ecb104f4b1aa36da3d312 (MD5) Previous issue date: 2015-05-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O monitoramento ac?stico passivo (MAP) permite a converg?ncia de solu??es para quest?es conservacionistas e cient?ficas e v?m sendo utilizado com sucesso para a examinar diversos aspectos da biologia de cet?ceos. Todavia, sua aplica??o para ambos os fins depende da correta interpreta??o dos dados coletados e portanto de conhecimentos pr?vios sobre o comportamento e o repert?rio ac?stico da(s) esp?cie(s) alvo(s). O sul do Brasil ? uma importante ?rea de reprodu??o para baleias francas austrais (Eubalaena australis). Esta esp?cie amea?ada agrega-se anualmente entre Julho e Novembro principalmente no estado de Santa Catarina. Medidas de prote??o s?o necess?rias para assegurar a recupera??o e para mitigar os efeitos de atividades antr?picas sobre esta popula??o. Visando construir conhecimento necess?rio para implementa??o de MAP como ferramenta de pesquisa e conserva??o da baleia franca no Brasil, o objetivo deste trabalho ? reunir informa??es sobre a ecologia ac?stica de pares-m?e filhote da esp?cie. Sensores aut?nomos foram instalados em duas localidades na APA Baleia Franca e continuamente monitoraram o ambiente e vocaliza??es de baleias francas. 1427 chamados com SNR > 10dB foram classificados em 7 categorias: upcall (55.8%), downcall (12.9%), v-call (12.3%), tonal constante (10.1%), tonal vari?vel (6.7%), h?brido (1.6%), pulsado (0.6%). A frequ?ncia de pico m?dia de todas as vocaliza??es foi 107.5?35.2 Hz e a dura??o m?dia foi de 0.8? 0.7s. A an?lise do padr?o nictemeral do comportamento vocal mostrou que o raking m?dio das taxas ajustadas de vocaliza??o em cada per?odo (amanhecer, dia, noite e anoitecer) n?o variam significativamente (Kruskal-Wallis x2=5.86, df=3, p=0.12). Provavelmente, estes resultados est?o relacionados a ontogenia comportamental dos pares e refletem a rela??o espacial entre m?es e seus respectivos filhotes no per?odo final de perman?ncia na ?rea de invernagem. Grava??es realizadas com um arranjo linear de hidrofones sincronicamente a observa??es comportamentais, revelaram que a taxa de emiss?o de chamados est? relacionada ao n?vel de atividade em cada estado comportamental. Em estados de maior atividade, como durante intera??es entre pares e entre m?es e seus filhotes, a taxa de emiss?o de chamados foi respectivamente 3.35 e 0.21 chamados/minuto. Por outro lado, enquanto se deslocando ou em descanso, a taxa de vocaliza??o foi de 0.12 e 0.02 chamados/minuto. Nenhuma vocaliza??o foi atribu?da aos pares focais em mergulho ou amamentando. Os testes exato de Fisher (F=14.82; p=0.21) e chi-quadrado (x2=19.06; df=15; p=0.37) revelaram que a associa??o entre os tipos de chamados e os estados comportamentais n?o ? significativa. Por?m classes de chamados distintas foram emitidas em propor??es diferentes em cada estado comportamental. O significado funcional das classes de vocaliza??o no contexto da comunica??o de pares f?mea-filhote ? semelhante a aquele descrito em estudos pr?vios, realizados com outros tipos de grupo da esp?cie. A composi??o de informa??es gerada por este trabalho constitui as bases do conhecimento acerca da bioac?stica da baleia franca no Brasil e ser?o fundamentais para a implementa??o de ferramentas de monitoramento e preserva??o baseadas em princ?pios ac?sticos. Al?m disso, representam um importante passo para a expans?o do conhecimento do comportamento vocal de pares m?o-filhote, um subgrupo vulner?vel por?m vital para as popula??es. / Remote acoustic sensing has been used to investigate several aspects of cetacean ecology and behaviour as occurrence, population density and impacts of anthropogenic sounds on communication systems. Nonetheless, the efficiency of PAM methods depends on the ability of researchers to detect and interpret acoustic signals and therefore on baseline information about natural features of the target species?vocal behaviour. The coastal waters off the state of Santa Catarina, Brazil, are an important wintering ground for Southern right whales (Eubalaena australis). Right whales aggregates in this area year after year, between July and November and protection measures are due to ensure the safety and health of this population. Aiming to build the required knowledge to use PAM as a right whale conservation and research tool in Brazil, the objective of the present study is to gather information concerning the acoustic ecology of right whale mother-calf pairs off Santa Catarina. Bottom-mounted archival acoustic recorders were deployed in two locations at the Right Whale APA during the wintering season. 1427 right whale calls with SNR? were classified in 7 call classes accordingly to visual and aural characteristics: upcall (55.8%), downcall (12.9%), down-up call (12.3%), tonal constant (10.1%), tonal variable (6.7%), hybrid (1.6%)and pulsive (0.6%). Mean values of start, end, maximum and minimum frequencies, frequency bandwidth, peak frequency and duration were calculated. Temporal pattern analysis revealed no significant diel trend in the emission of contact calls (Kruskal-Wallis test chi-square=5.86, df=3, P=0.12). Results may be linked to the predominant behavioral of whale groups through the period of stay at the wintering area. Using synched surface-behavioral observations and acoustic recordings, calling rates were obtained and the use of call classes in different behavioral states was discussed. Callingrates (call/min) were associated with the activity level of mo/ca pairs, greater in interactions and bonding and lower during travelling and resting. No calls were attributed to diving or nursing pairs. Upcalls and down-upcalls calls were attributed to resting pairs as well as traveling pairs. Constant calls were detected when a pair was swimming toward the research boat and pulsive calls were detected in the presence of dolphins in close proximity to the dislocating focal group. Interestingly, mo/ca pairs spend 20% of the sampling time interacting with other pairs and the greatest diversity of calls was recorded during such events. Pulsive (12%) and hybrid calls (13%-exclusively recorded during mo/ca interactions) are characteristics of agonistic behavior between whales. When bonding, mother and/or calves produced exclusively upcalls.The adaptative significance of previously described calls in mother-calf pair ?s communication is similar to what has been described for other whale groups.This dissertation brings significant information that constitutes bases of right whale bioacoustics in Brazil, and therefore will be vital for the implementation of mitigation, monitoring and investigation tools based on acoustic principles. Moreover, it contributed to fulfil the lack of behavioural and acoustic data of mother-calf pairs a highly vulnerable and vital subgroup for all right whale populations.
3

Atividade de morcegos inset?voros (mammalia, chiroptera) no pampa brasileiro: uso de h?bitat e sazonalidade

Barros, Mar?lia Abero S? de 30 May 2012 (has links)
Made available in DSpace on 2014-12-17T15:37:13Z (GMT). No. of bitstreams: 1 MariliaASB_DISSERT.pdf: 1394968 bytes, checksum: b076e332a2c3f4b9375156425fad6f0f (MD5) Previous issue date: 2012-05-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region / Os morcegos correspondem a 20% dos mam?feros atuais e, com poucas exce??es, apresentam ecolocaliza??o, um sistema de orienta??o espacial a partir da emiss?o e an?lise de ecos de ondas sonoras, geralmente ultrassons. A ecolocaliza??o foi descoberta na d?cada de 1940 e a partir de 1970 detectores de ultrassons tornaram-se comercialmente dispon?veis, permitindo a investiga??o de diversos aspectos sobre hist?ria natural e ecologia de morcegos. Monitoramentos ac?sticos passivos tem sido frequentemente utilizados em estudos de uso de h?bitat, principalmente na Am?rica do Norte e Europa, comparando-se diferentes locais quanto ao n?mero de vezes em que morcegos s?o detectados. A presente disserta??o apresenta a primeira avalia??o de padr?es espaciais e sazonais na atividade de quir?pteros inset?voros do Brasil, realizada no bioma Pampa, Estado do Rio Grande do Sul. Uma vez que a atividade de morcegos pode variar de acordo com o h?bitat, o per?odo do ano e condi??es clim?ticas, foram testadas as seguintes hip?teses: 1. a atividade de morcegos ? heterog?nea entre diferentes tipos de h?bitat; 2. a atividade apresenta varia??es sazonais; 3. a atividade ? influenciada pela temperatura, umidade e velocidade do vento. As amostragens ac?sticas foram realizadas em transectos fixos de 1500 metros, monitorados mensalmente de abril de 2009 a mar?o de 2010. Os transectos abrangeram cinco tipos de h?bitat: Eucaliptos, Mata Ciliar, Banhado, Canal e Campo. Em cada amostragem, foram obtidos o n?mero de registros de atividade com um detector de ultrassons Pettersson D230. No total, foram obtidos 1183 registros de atividade, sendo que os maiores n?veis de atividade de quir?pteros foram observados em ?rea de ?rvores de eucaliptos de grande porte (1,93 registros/3 min) e de um canal (1,61 registros/3 min). Em segundo lugar, a borda de uma mata ciliar (0,94 registros/3 min) e a margem de um banhado (0,61 registros/3 min) apresentaram n?veis estatisticamente equivalentes de atividade. As ?reas de campo foram menos utilizadas. A atividade de quir?pteros n?o apresentou correla??o com os fatores abi?ticos. Por?m, foi significativamente menor na esta??o mais fria, o inverno, e apresentou valores similares no outono, primavera e ver?o. A prefer?ncia por bordas de vegeta??o e cursos d??gua coincide com o documentado para outros pa?ses e ? atribu?da principalmente ? concentra??o de presas nestes tipos de ambiente. Do mesmo modo, a diminui??o da atividade no inverno ? provavelmente uma resposta ? menor disponibilidade de insetos, al?m das baixas temperaturas. Nossos dados indicam que ?reas de vegeta??o arb?rea e cursos d??gua s?o priorit?rias para a conserva??o de morcegos e que altera??es nestes tipos de h?bitat tendem a influenciar negativamente a atividade de morcegos na regi?o

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