Banca de DEFESA: LUANE MARIA STAMATTO FERREIRA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : LUANE MARIA STAMATTO FERREIRA
DATA : 28/02/2019
HORA: 14:00
LOCAL: Sala Darwin
TÍTULO:

The call of the (Neotropical) wild: maned wolf long-range acoustic ecology.

PALAVRAS-CHAVES:

Chrysocyon brachyurus, canid, vocalization, sound propagation, passive acoustic monitoring, temporal patterns, playback.

PÁGINAS: 189
GRANDE ÁREA: Ciências Humanas
ÁREA: Psicologia
RESUMO:

Maned wolves are difficult to observe in the wild because of their low densities and of their cryptic and crepuscular-nocturnal habits. Exploring their long-range call – the roar-bark – is an efficient alternative to study the species. We used a combination of methodologies: we played back roar-barks in their natural habitat to test how free-ranging animals would respond and to understand the propagation properties of this vocalization in the wild; we recorded spontaneous roar-bark sequences of wild maned wolves through a grid of autonomous recorders for eight months to reveal long term temporal patterns; and we used captivity records to access gender and individuality in the roar-bark and test its application on natural recordings. We found that maned wolves vocalize more on the beginning of the night, and this was the only period we obtained responses during the playback experiment, despite dawn being the best propagation period for roar-bark transmission. Social factors may be influencing the timing of their long-range vocal activity. We suggest that roar-barks may be an honest advertisement of quality for territorial defense. Maned wolves vocalize more on better moonlit nights, especially when the first half of the night is illuminated, likely as a consequence of reduced foraging time and therefore having more time to invest in acoustic communication. It was possible to identify the mating and circa-parturition period in the natural recordings by an increase in solo and group vocal activity, which indicates a role of roar-barks in partner attraction/guarding and intra-familiar-group communication. In captivity, male roar-barks were distinguishable by their longer duration, also indicating a sexual function and suggesting a higher energy investment to advertise motivation. Roar-barks were also individually distinct. However, site characteristics, such as presence of vegetation, drastically affected both the propagation of broadcasted roar-barks and most identity and gender parameters’ transmission in the wild. Elevating the speaker 45° upward to simulate the head/muzzle position during vocalization lead to lower sound intensities, but partially counteracted the negative effects of vegetation on signal transmission. The few stable parameters were able to discriminate individuals, although with lower success rate. In wild recordings the variation of parameters due to propagation was larger than the variation due to individual differences limiting passive acoustic monitoring as a means of counting individuals in their natural habitats. Despite the present limitation of vocal identification in the wild, bioacoustics tools proved efficient in revealing the secretive behavior ecology of maned wolves.

MEMBROS DA BANCA:
Externo à Instituição - HOLGER KLINCK
Externo à Instituição - JEFFREY EDWARD PODOS - UMASS
Externa à Instituição - JULIE PATRIS
Presidente - 1863735 - RENATA SANTORO DE SOUSA LIMA MOBLEY
Externa à Instituição - SUSAN PARKS - SYR