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Killer whales (Orcinus orca) have group-specific call repertoires that can be used to track groups and populations using passive acoustic monitoring. To provide a detailed description of the Icelandic killer whale repertoire and its variation, we analyzed acoustic data collected in five locations between 1985 and 2016. Calls were classified manually, and CART and random forest analyses were employed to validate the manual classification. A total of 91 call categories (including call types and subtypes) were defined. Most call categories were recorded in more than one location, with the highest proportion shared between herring grounds in Vestmannaeyjar (South) and Breiðafjörður (West). However, both locations included call categories that were not recorded elsewhere in Iceland. Recordings from past herring wintering grounds in eastern Iceland included few call categories that matched other locations. Sample sizes from Reykjanes (Southwest) and Skjálfandi (North) were small and did not include unique call categories. The relative occurrence of call categories in Vestmannaeyjar changed little over a 14-year period (2002-2016), although shorter-term changes between years were observed that appeared to correlate to changes in individuals identified. This comparison of acoustic repertoires provides valuable information on the social structure and movement patterns of herring-eating killer whales around Iceland. [ABSTRACT FROM AUTHOR]

During glacial periods, highly mobile species were able to shift their ranges to warmer regions that remained ice-free--so-called "glacial refugia." Glacial refugia often preserved higher levels of genetic diversity than areas that were colonized after the retreat of glaciers. In this study, we examined genetic and vocal variation in R-type ("resident") killer whales, Orcinus orca, from Nemuro Strait in the western North Pacific to test the hypothesis that environmentally stable marine regions may have preserved refugial populations of the killer whale that retained historical genetic and cultural diversity. We found three distinct mtDNA control region haplotypes and stereotyped calls that differed significantly from the repertoire of a population further north off Kamchatka and the adjacent western North Pacific. Therefore, both genetic and cultural evidence suggest that at least some killer whales from Nemuro Strait represent a separate maternal lineage. The control region haplotype diversity for Nemuro Strait is comparable to that for the rest of the North Pacific. The data presented here are consistent with the existence of the southwestern glacial refugium for killer whales in the waters off northern Japan during the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

Also, the density of cookie-cutter shark scars seemed to be noticeably higher in Sato's beaked whales than in Baird's beaked whales (which was also noted by Yamada et al., 2019). We noticed, as also noted by Brownell and Kasuya (2021), that Sato's beaked whales are shyer and less tolerant to the approaching boat than the Baird's beaked whales we observed at the Commander Islands. Beaked whales (Family Ziphiidae, Odontoceti, Cetacea) are one of the least studied groups of cetaceans. [Extracted from the article]

Cetacean species are highly mobile, most of them regularly travelling over long distances, thereby presenting complex obstacles to their conservation. Identification of their critical habitats, specifically those parts of a cetacean's range that are essential for day‐to‐day survival and for maintaining a healthy population growth rate, is necessary for their effective protection.This study presents a summary of the data on cetacean sightings during surveys that covered substantial parts of the Russian Far East coastal waters from the Okhotsk Sea to Chukotka in order to determine important areas for particular cetacean species. Sixteen cetacean species were registered during the surveys, and for 12 of them with sufficient numbers of sightings, zones with maximum sighting rates were identified.Only 13% of all cetacean sightings and 22% of sightings of protected species occurred within marine protected areas (MPAs). The highest sighting rates for protected species were concentrated off north‐eastern Sakhalin Island, in the Shantar Area, in Anadyr Gulf, in Kresta Bay and in the waters off eastern Chukotka. The analysis of the distribution patterns of various cetacean species in Russian Far East seas provides a solid base for future conservation planning. Lack of specific MPAs for protection of cetaceans and associated biodiversity hinders marine conservation in Russian Far East seas.The study highlights the specific zones important for various cetacean species and suggests the extension of some existing MPAs and the creation of new MPAs for future spatial habitat protection measures. [ABSTRACT FROM AUTHOR]

Killer whale call repertoires can provide information on social connections among groups and populations. Killer whales in Iceland and Norway exhibit similar ecology and behavior, are genetically related, and are presumed to have been in contact before the collapse of the Atlanto‐Scandian herring stock in the 1960s. However, photo‐identification suggests no recent movements between Iceland and Norway but regular movement between Iceland and Shetland. Acoustic recordings collected between 2005 and 2016 in Iceland, Norway, and Shetland were used to undertake a comprehensive comparison of call repertoires of Northeast Atlantic killer whales. Measurements of time and frequency parameters of calls from Iceland (n = 4,037) and Norway (n = 1,715) largely overlapped in distribution, and a discriminant function analysis had low correct classification rate. No call type matches were confirmed between Iceland and Norway or Shetland and Norway. Three call types matched between Iceland and Shetland. Therefore, this study suggests overall similarities in time and frequency parameters but some divergence in call type repertoires. This argues against presumed past contact between Icelandic and Norwegian killer whales and suggests that they may not have been one completely mixed population. [ABSTRACT FROM AUTHOR]

Killer whales are top predators in marine trophic chains, and therefore their feeding preferences can substantially affect the abundance of species on the lower trophic levels. Killer whales are known to feed on many different types of prey from small fish to large whales, but a given killer whale population usually focuses on a specific type of prey. Stable isotope analysis is widely used to study whale diets, because direct observations are often impossible. Killer whale feeding habits in the western North Pacific are poorly studied, and the large‐scale stable isotope analysis provides a unique opportunity to gain insights into the trophic links of this top predator. In this study, we compare the δ13C and δ15N stable isotope values from killer whale skin samples obtained in different areas of the western North Pacific from fish‐eating (R‐type) and mammal‐eating (T‐type) killer whale ecotypes. The effect of ecotype was highly significant: both carbon and nitrogen stable isotope values were lower in R‐type whales than in T‐type whales. The geographical variation also affected killer whale stable isotope values due to both the differences in killer whale diet and the variation in baseline stable isotope values across the study areas. [ABSTRACT FROM AUTHOR]

Humpback whales migrate seasonally from high latitude feeding areas to lower latitude breeding areas for mating and calving. In 2004-2006, a North Pacific basin-wide study called SPLASH was conducted as an international collaboration among various groups of researchers. The Russian Far East consists of multiple high latitude feeding areas and during SPLASH, 102 whales were identified and compared to catalogs from breeding areas. Our goal in this study was to further investigate the migratory destinations of whales from the Russian Far East using a total of 1,459 photographs of whales identified from 2004 to 2014. We compared the latest Russian catalog with the SPLASH catalog from wintering areas (2004-2006) and with two additional regional catalogs from Okinawa (1989-2006) and the northern Philippines (2000-2006). We found a total of 152 matches: 106 with Asian, 35 with Hawaiian, and 11 with Mexican breeding grounds. The match rate was higher in mainland Kamchatka and consisted mostly of whales from the Asian breeding ground. In the Commander Islands, the proportion of whales from Asia was twice that of Hawaii and six times higher than Mexico. The total match rate was low, supporting the hypothesis of some undiscovered humpback whale breeding location in the North Pacific. [ABSTRACT FROM AUTHOR]

There are two recognized species in the genus Berardius, Baird's and Arnoux's beaked whales. In Japan, whalers have traditionally recognized two forms of Baird's beaked whales, the common 'slate-gray' form and a smaller, rare 'black' form. Previous comparison of mt DNA control region sequences from three black specimens to gray specimens around Japan indicated that the two forms comprise different stocks and potentially different species. We have expanded sampling to include control region haplotypes of 178 Baird's beaked whales from across their range in the North Pacific. We identified five additional specimens of the black form from the Aleutian Islands and Bering Sea, for a total of eight 'black' specimens. The divergence between mt DNA haplotypes of the black and gray forms of Baird's beaked whale was greater than their divergence from the congeneric Arnoux's beaked whale found in the Southern Ocean, and similar to that observed among other congeneric beaked whale species. Taken together, genetic evidence from specimens in Japan and across the North Pacific, combined with evidence of smaller adult body size, indicate presence of an unnamed species of Berardius in the North Pacific. [ABSTRACT FROM AUTHOR]

Word cloud generating applications were originally designed to add visual attractiveness to posters, websites, slide show presentations, and the like. They can also be an effective tool in reading and writing classes in English as a second language ( ESL) for all levels of English proficiency. They can reduce reading time and help to improve writing skills and vocabulary comprehension. They can also be used to address elements of rhetoric in students' essays and instructors' assignment descriptions and syllabi. Word clouds can be used as a visual aid to present new vocabulary and a study tool for quizzes. Most applications work with printed and online texts and students' authentic writing. They find corpus vocabulary in texts and use it to create word clouds. Knowing key words helps students understand and summarize the texts they read. When students determine which words they use most often in their writing, they are advised to learn the spelling and collocations of those words, find synonyms to avoid repetition, and use word maps to create a particular tone of voice to sound (for example) humorous or sad. This article introduces word cloud generators, which are free, user-friendly online tools that can be easily incorporated into ESL classroom activities to enhance student learning experience. [ABSTRACT FROM AUTHOR]

The article discusses the endangered North Pacific right whales that can be found in Russian waters in 2003-2014. The species also known as Eubalaena japonica is considered as one of the most endangered baleen whale species in the world. A number of cetacean surveys conducted by a group of Japanese in the North Pacific and Sea of Okhotsk, providing the sightings of North Pacific right whales is also tackled.

The social structure of Baird's beaked whales is completely unstudied, and it is unknown if either females or males form long-term social associations or occur in stable groups. In this paper we summarize our observations of individually identified animals over the span of 6 yr to provide insight on their long-term social structure. We have identified 122 whales, with 28 of them encountered three times or more and thus included in the analysis of social structure. We found that the whales exhibited nonrandom patterns of social associations with some individuals preferentially associating with each other. Whales with more scarred skin had higher maximum association coefficients, which indicates that older animals and/or males were more inclined to form stable associations. Cluster analysis with a modularity test for gregariousness divided the whales into four clusters. Whales from the same clusters did not always occur together, but some individuals retained stable associations over several years. The strength of social relationships decayed over periods of months, with between-year relationships showing little deviation from what would be expected if association was random. Generally these findings do not correspond to a stable society with fixed groups but instead suggest a fission-fusion society with some stable alliances. [ABSTRACT FROM AUTHOR]

Humpback whales feed on a variety of prey, but significant differences likely occur between regional feeding grounds. In this study, the diets of humpback whales were analyzed by comparing stable isotope ratios in animal tissues at three humpback whale feeding grounds in the Russian Far East: Karaginsky Gulf, Anadyr Gulf, and the Commander Islands. Anadyr Gulf is a neritic zone far from a shelf break, Karaginsky Gulf is a neritic zone close to a shelf break, and the Commander Islands represent an open oceanic ecosystem where whales feed off the shelf break. Samples from the Commander Islands had the lowest mean δ13C and δ15N values (mean ± SE: δ13C = −18.7 ± 0.1, δ15N = 10.4 ± 0.1) compared to the samples from Karaginsky Gulf (δ13C = −17.2 ± 0.1, δ15N = 12.7 ± 0.2) and Anadyr Gulf (δ13C= −17.8 ± 0.1, δ15N = 14.0 ± 0.4). The samples from Anadyr Gulf had the highest δ15N values, while the samples from Karaginsky Gulf had the highest δ13C values. Both δ13C and δ15N values differed significantly among all three areas. Our data support the hypothesis that humpback whales tend to feed on fish in neritic areas and on plankton in deep oceanic waters. [ABSTRACT FROM AUTHOR]

Killer whales produce repertoires of stereotyped call types that are primarily transmitted vertically through social learning, leading to dialects between sympatric pods. The potential function of these call repertoires remains untested. In this study, we compared the reaction of Kamchatkan fish-eating killer whales to the playbacks of calls from the same and different pods. After the playback of recordings from a different pod, in three cases whales changed the direction of their movement toward the boat, and in three cases no changes in direction were observed. After the playback of recordings from the same pod (either from the same or a different unit within the pod), in seven cases whales changed the direction of their movement toward the boat, and in only one case no change in direction was observed. Whales remained silent after all six playbacks of recordings from a different pod, even when they changed direction toward the boat. After the playback of recordings from the same pod, however, in all eight cases whales started calling in response. Our playback study shows that killer whales may react to playbacks of conspecific sounds and that reactions are dependent on the type of playback stimuli. [ABSTRACT FROM AUTHOR]

In grassland in the vicinity of Kharkiv, Ukraine, we determined the floristic composition of the plant communities, v-values of the species and above-ground plant biomass. The plant communities in Kharkiv were dominated by Stipa capillata L., Medicago romanica Prodan, Inula ensifolia L. and Poa angustifolia L. There were 46 species in eight 1-m2 quadrates and the above-ground plant biomass was 245 g m−2 in the Stipa capillata stand. In the Medicago romanica stand, the number of species and above-ground plant biomass were 37 per 10 quadrates of 1 m2 and 195 g m−2, respectively. The numbers of species in the stands were 40 in Poa angustifolia and 45 in Inula ensifolia. The plant biomass of the Poa angustifoia stand was 380 g m−2. These values were similar to those from Inner Mongolia. The species diversity of the stand ( H) was calculated as: H = −Σ pi log2  pi. The species diversity of the two stands was 2.98 for the Stipa capillata stand and 2.66 in the Medicago romanica stand. The stand changed by various human impacts, such as grazing and cultivation. Plantago schwarzenbergiana Schur. seemed to become established after the exposure of Stipa capillata stands to grazing, while Inula ensifolia stands became established in an abandoned field. The species composition in Kharkiv was different from that of Inner Mongolia, though the genus of plants was similar. [ABSTRACT FROM AUTHOR]