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Satellite imagery has been used to improve scientific research worldwide. In this study, the southern right whale (Eubalaena australis) was chosen to test the use of medium, high, and very high resolution (VHR) satellite images, on the Brazilian breeding ground. These images were used to identify the whales and were compared to aerial survey data collected in the same area. The VHR satellite images from the Pleiades‐1A satellite, available on Google Earth, displayed the best results when compared to those from Sentinel 2, Landsat 8, Rapid Eye, and Planet Scope. No significant differences were observed (Mann‐Whitney U test) between the possible whales recorded in the satellite images and of real whales recorded in situ by aerial surveys, while considering either the number of groups (p =.841, n = 5) or the total number of animals (p =.222, n = 5). Further, when using VHR images, the geographical positions of the whales recorded in situ had a positive correlation with the positions generated from the satellite images (Mantel test: r = 0.52, p =.001, n = 13). This technique may represent an important tool for detecting right whales, especially in countries where research funding is scarce. [ABSTRACT FROM AUTHOR]

Santa Catarina State, in southern Brazil, is an important breeding ground for the southern right whale and it is possible to record mother‐calf pairs and unaccompanied adults that migrate to this coast to either give birth, mate, or socialize. From the geographical position of the sightings, spatial segregation was evaluated between mother‐calf pairs and unaccompanied whales. Using GAM, we analyzed 15 years of aerial survey data from 2003 to 2018. The study area (780 km2) was divided into 500 × 500 m grid cells. Whale count per grid cell was modeled using a set of explanatory variables. The explanatory variables of latitude, coast distance, seabed, and maximum SST were selected for both classes. However, coast type was also selected for unaccompanied whales, while coast linearity and bathymetric slope were additionally selected for mother‐calf pairs. The response curves fitted by models indicated a certain degree of spatial segregation, by which mother‐calf pairs remained closer to the coast, where the curve peak is reached at 500 m from the coast, compared to unaccompanied whales where the curve peaked near 1,000 m from the coast. Also, unaccompanied whales more frequently appeared in the southern boundaries of the study area, at latitudes south from 28.4°S. [ABSTRACT FROM AUTHOR]

Summary: Cetacean morbillivirus (CeMV) has caused repeated epizootics and interepizootic fatalities in a variety of cetacean species worldwide. Recently, a novel CeMV strain (GD‐CeMV) was linked to a mass die‐off of Guiana dolphins (Sotalia guianensis) in Brazil. Southern right whales (SRWs; Eubalaena australis) migrate to the southern Brazilian coast during austral winter and spring (June through November) for breeding and calving. Because unexplained high calf mortality rates have recurrently been documented in SRWs, we hypothesized they could be infected with CeMV. We developed a novel real‐time RT‐PCR method based on SYBR®GREEN for detection of CeMV and identified the virus in three out of five stranded SRWs from Santa Catarina state, Brazil. The partial sequences of the morbillivirus phosphoprotein gene suggest that the virus is similar to the GD‐CeMV strain. Our results indicate CeMV can infect SRWs and should be considered in the differential aetiologic diagnosis of infectious diseases in this species. It also raises concern for potential conservation implications for this species in its main coastal breeding area off Southern Brazil. [ABSTRACT FROM AUTHOR]