Using combined acoustic tracking and visual observation techniques to study humpback whales

1995 ◽  
Vol 97 (5) ◽  
pp. 3353-3353
Author(s):  
Adam S. Frankel ◽  
Christopher W. Clark
Keyword(s):  
Visual Observation ◽  
Humpback Whales ◽  
Acoustic Tracking

scholarly journals Have whales returned to a historical hotspot of industrial whaling? The pattern of southern right whale Eubalaena australis recovery at South Georgia

2020 ◽  
Vol 43 ◽  
pp. 323-339
Author(s):  
JA Jackson ◽  
A Kennedy ◽  
M Moore ◽  
A Andriolo ◽  
CCG Bamford ◽  
...  
Keyword(s):  
Visual Observation ◽  
Humpback Whales ◽  
Lower Latitude ◽  
The South ◽  
South Georgia ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Antarctic Waters ◽  
Skin Biopsies ◽  
Strong Contrast

Around 176500 whales were killed in the sub-Antarctic waters off South Georgia (South Atlantic) between 1904 and 1965. In recent decades, whales have once again become summer visitors, with the southern right whale (SRW) the most commonly reported species until 2011. Here, we assess the distribution, temporal pattern, health status and likely prey of SRWs in these waters, combining observations from a summertime vessel-based expedition to South Georgia, stable isotope data collected from SRWs and putative prey and sightings reports collated by the South Georgia Museum. The expedition used directional acoustics and visual surveys to localise whales and collected skin biopsies and photo-IDs. During 76 h of visual observation effort over 19 expedition days, SRWs were encountered 15 times (~31 individuals). Photo-IDs, combined with publicly contributed images from commercial vessels, were reconciled and quality-controlled to form a catalogue of 6 fully (i.e. both sides) identified SRWs and 26 SRWs identified by either left or right sides. No photo-ID matches were found with lower-latitude calving grounds, but 3 whales had gull lesions supporting a direct link with Península Valdés, Argentina. The isotopic position of SRWs in the South Georgia food web suggests feeding on a combination of copepod and krill species. Opportunistic reports of SRW sightings and associated group sizes remain steady over time, while humpback whales provide a strong contrast, with increased sighting rates and group sizes seen since 2013. These data suggest a plateau in SRWs and an increasing humpback whale presence in South Georgia waters following the cessation of whaling.

scholarly journals Cetacean community off French Guiana

2021 ◽  
Author(s):  
Claire Pusineri ◽  
Ludivine Martinez ◽  
Amandine Bordin ◽  
Benjamin De Montgolfier ◽  
Ophélie Deffes ◽  
...  
Keyword(s):  
French Guiana ◽  
Beaufort Sea ◽  
Visual Observation ◽  
Humpback Whales ◽  
Common Dolphin ◽  
Physeter Macrocephalus ◽  
Sea State ◽  
Cetacean Species ◽  
Spotted Dolphin ◽  
Guiana Dolphin

Although human activities are developing in French Guiana Exclusive Economic Zone (EEZ) and surrounding countries, knowledge on diversity and ecology of cetaceans in the region is scarce. This study aimed to collect new information on the cetacean species occurring year-round in the entire French Guiana EEZ by combining visual and acoustic data obtained from three boat-based campaigns conducted by local NGOs. The GEPOG campaign was conducted from July 2011 to June 2012, four days every two months; the COHABYS campaign was performed five days per month from January to May 2018; the OSL campaign consisted in four 10-day surveys conducted in June, July, September and October 2018. The visual observation effort conducted when Beaufort sea state < 5 was 1,961 km, 1,491 km and 3,243 km respectively. Acoustic records were done when Beaufort sea state < 5 during daylight and/or nighttime, depending on the survey. A total of 132 cetacean sightings were done. Five cetacean families and 15 species were identified. Delphinidae was the family most frequently sighted (91% to 100% of groups and 99% to 100% of individuals per campaign). The most frequent species in the area were identified, along with their distribution and phenology: Guiana dolphin (Sotalia guianensis) was found in the coastal area (0-20 m), the long-beaked common dolphin (Delphinus delphis) was sighted on the shelf (20-100 m), along with the bottlenose dolphin (Tursiops truncatus) and the Atlantic spotted dolphin (Stenella frontalis) that were also common on the upper slope (100-1,500 m). Finally, the spinner dolphin (Stenella longirostris), the melon-headed whale (Peponocephala electra) and the pantropical spotted dolphin (Stenella attenuata) were frequent on the slope (100-3,500 m). The results suggest these species may be found in French Guiana waters all year round and mother and calf pairs, as indicator of reproduction, were observed for all of them except the long-beaked common dolphin and the Guiana dolphin. Mother and calf pairs of humpback whales (Megaptera novaeangliae), that potentially belong to the “A” stock, were also sighted twice, as well as two groups of sperm whales (Physeter macrocephalus) with calves. Hence, these results showed that French Guiana bears a particular responsibility for the conservation of cetacean biodiversity, but a lot remains to be done to strengthen knowledge and conservation of these species in the territory.

Modeling cetacean habitat use in an urban coastal area in southeastern Brazil

2020 ◽  
Vol 642 ◽  
pp. 227-240
Author(s):  
L Lodi ◽  
R Tardin ◽  
G Maricato
Keyword(s):  
Habitat Use ◽  
Protected Areas ◽  
Linear Models ◽  
Anthropogenic Activities ◽  
Buffer Zone ◽  
Humpback Whales ◽  
Southeastern Brazil ◽  
Major Influence ◽  
Cetacean Species ◽  
Few Data

Most studies of cetacean habitat use do not consider the influence of anthropogenic activities. We investigated the influence of environmental and anthropogenic variables on habitat use by humpback Megaptera novaeangliae and Bryde’s whales Balaenoptera brydei off the coast of the Brazilian city of Rio de Janeiro. Although there are 2 marine protected areas (MPAs) in this area, few data are available on cetacean habitat use or on the overlap of different cetacean species within these MPAs. Our aim was to evaluate the effectiveness of the MPAs and propose a buffer zone to better protect the biodiversity of the study area. We conducted systematic surveys and developed spatial eigenvector generalized linear models to characterize habitat use by the species in the study area. Habitat use by humpback whales was influenced only by depth, whereas for Bryde’s whales there was the additional influence of anthropogenic variables. For Bryde’s whales, which use the area for feeding, sea surface temperature and the distance to anchorages had a major influence on habitat use. We also showed that neither of the MPAs in the study area adequately protects the hotspots of either whale species. Most of the humpback whale grid cells with high sighting predictions were located within 2 km of the MPAs, while areas of high sighting prediction of Bryde’s whales were located up to 5 km from the MPAs, closer to beaches. Our findings provide important insights for the delimitation of protected areas and zoning of the MPAs.

Conversion of surface plasmon polaritons into photons: visual observation

2011 ◽  
Vol 181 (3) ◽  
pp. 305 ◽  
Author(s):  
V.B. Zon ◽  
B.A. Zon ◽  
V.G. Klyuev ◽  
A.N. Latyshev ◽  
D.A. Minakov ◽  
...  
Keyword(s):  
Surface Plasmon ◽  
Surface Plasmon Polaritons ◽  
Visual Observation ◽  
Plasmon Polaritons

Overcoming Disorthography of Primary Schoolchildren with General Speech Underdevelopment

2020 ◽  
Vol 81 (3) ◽  
pp. 46-51
Author(s):  
I. V. Prishchepova
Keyword(s):  
Speech Therapy ◽  
Personality Development ◽  
Practical Importance ◽  
Visual Observation ◽  
Russian Language ◽  
Learning Activity ◽  
Image Study ◽  
Primary Schoolchildren ◽  
Oral Speech ◽  
Analysis And Synthesis

The article discusses mechanisms of various kinds of disorthography (conditioned by the underdevelopment of morphological, phonemic and graphical bases of orthographic activity) in schoolchildren with general speech underdevelopment. It offers basic methodology and techniques to correct disorthography conditioned by inadequate child acquisition of phonemic, traditional principles of orthography and principles of graphics. A systematic work on the development of psychological and language components of this type of learning activity coupled with oral speech disorder overcoming facilitates successful acquisition of program requirements by such children. The following methods were used: practical (exercises, modelling, construction, schematization, games), visual (observation, image study, image and practical activity results demonstration, stimulus material demonstration), verbal methods (conversation, narration, method of language analysis and synthesis, grammar and orthographic tasks solution). The article covers the results of many years of positive experience in the correction of various types of disorthography of primary schoolchildren with general speech underdevelopment. Formation of grammatical and orthographic activity, the basics of speech and language competences, Russian language academic performance increase are prerequisites of linguistic personality development and child self-development. The practical importance of the research lies in the development and testing of methods of disorthography correction of children with general speech underdevelopment. The given methodology helps to improve their spelling skills and allows to carry out a purposeful and controlled formation of spelling activity. The results can be used in the work of speech therapy centers and educational establishments which carry out inclusive students’ education.

Marine Mammal Acoustic Tracking from Adapting HARP Technologies

2009 ◽  
Author(s):  
Sean M. Wiggins ◽  
John A. Hildebrand
Keyword(s):  
Marine Mammal ◽  
Acoustic Tracking
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