Banca de DEFESA: DIANA CARVALHO DE FREITAS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : DIANA CARVALHO DE FREITAS
DATE: 22/12/2023
TIME: 08:30
LOCAL: virtual
TITLE:

Cetaceans in the Blue Amazon: occurrence, bioacoustic patterns and conservation

KEY WORDS:

Distribution, Humpback Whale, Melon-head Dolphin, Pantropical Spotted Dolphin, Bioacoustics, Marine Protected Areas, Conservation

PAGES: 135
BIG AREA: Ciências Biológicas
AREA: Zoologia
SUBÁREA: Comportamento Animal
SUMMARY:

Cetaceans can be found in oceanic, coastal, estuarine and river regions throughout the world. And despite the ecological importance of this group, essential information such as distribution and occurrence patthers are still scarce, especially for species with oceanic habits. The main objective of this thesis is to contribute to the understanding of the occurrence and bioacoustic patterns in sound emission from cetaceans in areas with little sampling effort, especially in the oceanic zones of the Northeast region of Brazil. Chapter 1 of this document deals with the occurrence of humpback whales in an area further north of the use limit considered for the species on the Brazilian coast. The presence of humpbacks was recorded through Passive Acoustic Monitoring carried out in the Barreirinhas Basin, Maranhão, in 2016. Here, we describe the songs of the males and compare the units sung with the song composition of the males from Itacaré, Bahia. We conclude that the singing males from the Barreirinhas Basin belong to Reproductive Stock A, the only stock that occurs on the Brazilian coast, and we suggest an expansion of the area that is commonly considered to be used by stock A. In chapter 2, we describe an unprecedented visual and acoustic record of melon-headed dolphins in the equatorial portion of the South Atlantic Ocean. The observed group had 300 to 400 individuals and was moving quickly, with occasional jumps. We present the acoustic parameters of 225 dolphin whistles and compare these data with records made of the species in other oceans. The frequencies of the whistles ranged from 4.74 to 31.47 kHz and the duration of the whistles from 0.03 to 2.80 seconds, with a mean (±SD) of 0.44 seconds (±0.40 seconds). In chapter 3, we present the acoustic parameters of 1,212 whistles of the pantropical spotted dolphin in two areas with different latitudes, the first in low latitudes close to the equator (02°-05°S), an area where there was no acoustic record for the species, and another area at latitude 14°S. In univariate tests, for the 10 acoustic parameters evaluated, 7 showed a significant difference between areas. And in the quadratic discriminant analysis this difference was also confirmed. We conclude that latitudinal variation and physical and oceanographic differences between the two environments can act as selection forces, shaping the acoustic behavior of the species in different habitats. In the final chapter, our objective was to answer the following question: are Brazil's marine protected areas delimited where there is the highest occurrence and density of cetaceans? We observed that the majority of conservation areas are coastal, with only seven Marine Protected Areas (MPAs) located after the shelf break. Therefore, we conclude that the current distribution of MPAs in Brazil is not sufficient and representative to cover the entire diversity of cetaceans that occur in our waters, especially in oceanic regions.

COMMITTEE MEMBERS:
Presidente - 1863735 - RENATA SANTORO DE SOUSA LIMA
Interno - 1476621 - DANIEL MARQUES DE ALMEIDA PESSOA
Interna - ***.973.494-** - LUANE MARIA STAMATTO FERREIRA - UFRN
Externa à Instituição - CAMILA DOMIT
Externa à Instituição - MARIA ISABEL CARVALHO GONÇALVES - UESC
Externa à Instituição - FERNANDA SCARANO CAMARGO
Externo à Instituição - RODRIGO HIPÓLITO TARDIN OLIVEIRA - UFRJ