Marcos Roberto Rossi-Santos

The Antarctic minke whale (Balaenoptera bonaerensis) (AMW) is one of the smallest species among baleen whales, occurring in the southern hemisphere from Antarctica to near the equator, and performing seasonal migrations from polar to tropical waters. Information about (AMW) occurrence in the winter breeding grounds is scarce, mostly coming from old records from whaling stations before the 1960’s international moratorium, such as Costinha Station in Northeastern Brazil (6° S / 34° W) and some sightings from few dedicated visual surveys. Acoustic methods can provide important data on the occurrence and distribution of migratory species. This work describes the occurrence of the Antarctic minke whale through acoustic detections of their “Bioduck” vocalisations in the Santos Basin, South-Southeastern Brazil (22° and 28° S / 42° and 48° W). Data was recorded between November 12 and December 19, 2015. AMW calls were detected for 12 days. We detected and classified 9 different Bio-duck calls in Brazilian coastal waters, evidencing a highly diverse acoustic behavior for the minke whale breeding ground. This is the first attempt to describe the acoustic diversity of AMW vocalizations in lower latitudes, contributing important information for future conservation efforts and management of AMW populations and their habitat. Therefore, our study presents the foremost acoustic evidence of the Antarctic minke whale in Brazilian coastal waters.

Cetaceans depend highly on acoustic signals, such as whistles, for social communication. Mixed-species associations (MSAs), temporary or long-term encounters between different species, may play an important role on the acoustic dynamics of the species involved. Because of whistles’ communication function, we used these sounds to investigate the acoustic relationships of Tursiops truncatus when involved in different group contexts: in MSAs with two other delphinid species and in single species group. Acoustic recordings of T. truncatus single species groups and in associations with Globicephala melas and Grampus griseus were collected in the Western South Atlantic Ocean through a towed array of hydrophones. A total of 1267 whistles were analysed and acoustical parameters were extracted. To verify the differences among whistles produced in such contexts a support vector machine and random forest analysis were implemented. Both analyses revealed a clear separation of whistles from the single species versus the MSA as well as between both MSAs. The results indicate that interspecific associations may influence the whistle structure and suggests that T. truncatus whistles can be modified during interspecific interactions. These findings are useful to elucidate the possible factors underlying behavioural plasticity and interspecific associations and to understand dolphins’ acoustic communication.

Acoustic methods can provide important data on the occurrence and distribution of migratory species. Information about Antarctic Minke whale ( Balaenoptera bonaerensis ) occurrence in the winter breeding grounds is scarce, mostly limited to old records from whaling stations before 1960’s international moratory, such as Costinha Station in Northeastern Brazil (6° S / 34° W). This work describes the occurrence of the Antarctic minke whale (AMW) through Bio-duck acoustic detections in the Santos Basin, South-Southeastern Brazil (22° and 28° S / 42° and 48° W), registered between November 12 and December 19, 2015. AMW calls were detected for 12 days. We detected and classified 9 different Bio-duck calls in Brazilian coast waters, evidencing a high diverse acoustic behaviour for the minke whale breeding ground. This is the first study to describe the acoustic diversity of AMW vocalizations in lower latitudes, constituting important information to the conservation and management of cetaceans and their habitat. Therefore, our study presents the foremost acoustic evidence of the Antarctic minke whale in Brazil, utilizing high technological passive acoustic methods, such as autonomous underwater vehicle (SeaGlider) sampling.

O guigó-da-caatinga, Callicebus barbarabrownae - Hershkovitz 1990, é o único primata endêmico do bioma caatinga no nordeste da Bahia. A espécie encontra-se ameaçada de extinção pela perda de habitat, causada principalmente pela supressão da vegetação e fragmentação das florestas onde se encontram. O presente estudo teve como objetivo localizar, com o auxílio de playback, e registrar os fragmentos ocupados por grupos de guigós no município de Banzaê, Bahia – Brasil. Além do registro de novas áreas de ocorrência, foi descrita a utilização de frutos dos gêneros Capparis (Brassicaceae) e Manilkara (Sapotaceae) pelos guigós.

This study investigated the emission of subaquatic noise from recreational tourism motorboats, schooners and a sea-bottom mounted water pump. Analyses demonstrated alterations in several whistle (IF:t = 2.42,P = 0.015; FF:t = −2.22,P = 0.025) and calls patterns (MIF:t = −3.13,P = 0.001; MAF:t = −3.49,P = 0.0005; FD:t = −2.21,P = 0.027; D:t = 2.89,P = 0.004), caused primarily by motorboats. Duration of clicks was also modified (D:t = −3.85,P = 0.0001), mainly by the water pump. The frequency range of all noises (0.43–35.8 kHz) overlaps that used by dolphins (1–48 kHz), causing sound emissions changes, with a considerable increase in number of whistles and a reduction in clicks trains. These changes may be a strategy developed by these dolphins to overcome the noise band. Mitigation measures, such as boating regulations and environmental education for the local community, boaters and tourists are needed to conserve the species. The Guiana dolphin population is apparently already suffering, evidenced by diminished residence time and reduced number of individuals entering the inlet during the presence of pleasure craft.