3,296 results on '"killer whale"'
Search Results
2. Individual variation in activity budgets of a stable population of killer whales in managed care across a year
- Author
-
Manitzas Hill, Heather M., Themelin, Manon, Dudzinski, Kathleen M., Felice, Michael, and Robeck, Todd
- Published
- 2025
- Full Text
- View/download PDF
Catalog
3. Assessment of the similarity-transformed equation of motion (STEOM) for open-shell organic and transition metal molecules.
- Author
-
Casanova-Páez, Marcos and Neese, Frank
- Subjects
- *
TRANSITION metals , *EQUATIONS of motion , *LARGE deviations (Mathematics) , *KILLER whale , *ORGANOMETALLIC compounds - Abstract
This study benchmarks the newly re-implemented single-reference excited-state methods, IP-EOM-CCSD, EA-EOM-CCSD, and STEOM-CCSD, in ORCA6.0, with a focus on open-shell systems. We compare STEOM against EOM-CCSD, CC3, and CCSDT across a range of systems, including small organic radicals, hydrated transition metal (TM) ions, and TM diatomic systems with both closed and open-shell configurations. For organic radicals, STEOM and EOM-CCSD show comparable performance, aligning closely with CC3 and CCSDT results. In the case of hydrated TM ions, IP-EOM closely matches DLPNO-CCSD results, while deviations from DLPNO-CCSD(T) are consistent. For open-shell TM systems, IP-EOM exhibits a blueshift relative to both the DLPNO-CCSD methods, while EA-EOM-CCSD shows better agreement. When comparing STEOM and CC3 to CCSDT, STEOM shows slightly larger deviations in closed-shell systems but shows excellent agreement in open-shell systems. Computational efficiency is also assessed, revealing a significant speedup in ORCA 6.0 compared to ORCA 5.0, with optimizations improving computation times. This study provides valuable insights into the performance and efficiency of STEOM in various chemical environments, highlighting its strengths and limitations. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
4. Accurate and efficient open-source implementation of domain-based local pair natural orbital (DLPNO) coupled-cluster theory using a t1-transformed Hamiltonian.
- Author
-
Jiang, Andy, Glick, Zachary L., Poole, David, Turney, Justin M., Sherrill, C. David, and Schaefer III, Henry F.
- Subjects
- *
COUPLED-cluster theory , *NATURAL orbitals , *WATER clusters , *ORBITAL interaction , *KILLER whale - Abstract
We present an efficient, open-source formulation for coupled-cluster theory through perturbative triples with domain-based local pair natural orbitals [DLPNO-CCSD(T)]. Similar to the implementation of the DLPNO-CCSD(T) method found in the ORCA package, the most expensive integral generation and contraction steps associated with the CCSD(T) method are linear-scaling. In this work, we show that the t1-transformed Hamiltonian allows for a less complex algorithm when evaluating the local CCSD(T) energy without compromising efficiency or accuracy. Our algorithm yields sub-kJ mol−1 deviations for relative energies when compared with canonical CCSD(T), with typical errors being on the order of 0.1 kcal mol−1, using our TightPNO parameters. We extensively tested and optimized our algorithm and parameters for non-covalent interactions, which have been the most difficult interaction to model for orbital (PNO)-based methods historically. To highlight the capabilities of our code, we tested it on large water clusters, as well as insulin (787 atoms). [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
5. Broadening access to small-molecule parameterization with the force field toolkit.
- Author
-
Zeng, Yunlin, Pavlova, Anna, Nelson, Philip M., Glick, Zachary L., Yang, Lan, Pang, Yui Tik, Spivak, Mariano, Licari, Giuseppe, Tajkhorshid, Emad, Sherrill, C. David, and Gumbart, James C.
- Subjects
- *
MOLECULAR dynamics , *SMALL molecules , *PARAMETERIZATION , *PROTEIN-protein interactions , *KILLER whale , *PARSING (Computer grammar) - Abstract
Access to accurate force-field parameters for small molecules is crucial for computational studies of their interactions with proteins. Although a number of general force fields for small molecules exist, e.g., CGenFF, GAFF, and OPLS, they do not cover all common chemical groups and their combinations. The Force Field Toolkit (ffTK) provides a comprehensive graphical interface that streamlines the development of classical parameters for small molecules directly from quantum mechanical (QM) calculations, allowing for force-field generation for almost any chemical group and validation of the fit relative to the target data. ffTK relies on supported external software for the QM calculations, but it can generate the necessary QM input files and parse and analyze the QM output. In previous ffTK versions, support for Gaussian and ORCA QM packages was implemented. Here, we add support for Psi4, an open-source QM package free for all users, thereby broadening user access to ffTK. We also compare the parameter sets obtained with the new ffTK version using Gaussian, ORCA, and Psi4 for three molecules: pyrrolidine, n-propylammonium cation, and chlorobenzene. Despite minor differences between the resulting parameter sets for each compound, most prominently in the dihedral and improper terms, we show that conformational distributions sampled in molecular dynamics simulations using these parameter sets are quite comparable. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
6. Utilizing Deep Incomplete Classifiers to Implement Semantic Clustering for Killer Whale Photo Identification Data
- Author
-
Barnhill, Alexander, Towers, Jared R., Nöth, Elmar, Maier, Andreas, Bergler, Christian, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Antonacopoulos, Apostolos, editor, Chaudhuri, Subhasis, editor, Chellappa, Rama, editor, Liu, Cheng-Lin, editor, Bhattacharya, Saumik, editor, and Pal, Umapada, editor more...
- Published
- 2025
- Full Text
- View/download PDF
7. Worldwide variation in shape and size of orca (Orcinus orca) saddle patches.
- Author
-
Mäkeläinen, Pirjo H., Visser, Ingrid N., Cooper, Tracy E., and Cusson, Mathieu
- Subjects
FINS (Anatomy) ,SADDLERY ,OCEAN ,ISLANDS - Abstract
The global distribution of Orcinus orca (orcas/killer whales) encompasses populations which differ from each other. Saddle patch shapes and sizes were compared for nearly 4,000 individuals, in 48 geographically or ecologically divided groups/populations/ecotypes (GP/E), in four Ocean Basins. Some Antarctic GP/E had five shapes, contrary to previous studies, which found only one shape in these Southern GP/E. Pacific Resident ecotypes had the highest variation in saddle patch shapes. Globally, the most common shape was the 'Smooth' category. Saddle patch sizes were measured using a ratio of the width of the saddle patch compared to the width of the dorsal fin base and averaged within each GP/E. The narrowest saddle patches were observed in New Zealand waters. The widest saddle patches were observed at the Crozet Islands and the Falkland Islands (Islas Malvinas). Globally, we found that the shape and size of saddle patches helped to define various GP/E, reinforcing earlier predictions that this pigmentation may be indicative of population divisions. Our findings may help with describing poorly defined or undescribed ecotypes. Such results may therefore aid assessments by management authorities/policy makers and provide levels of guidance in the creation of conservation or recovery plans. [ABSTRACT FROM AUTHOR] more...
- Published
- 2025
- Full Text
- View/download PDF
8. Occurrence and Coastal Mortality of Cetaceans on the Arctic Coast of the Chukotka Peninsula in the Waters of Cape Vankarem, 2017–2021.
- Author
-
Zargebelniy, S. V.
- Subjects
- *
KILLER whale , *WHITE whale , *CETACEA , *WALRUS , *TERRITORIAL waters , *HUMPBACK whale , *WHALES - Abstract
Six species of cetaceans have been found to occur in the Chukchi Sea adjacent to the Pacific walrus rookery at Cape Vankarem: the gray whale, the bowhead whale, the humpback whale, the killer whale, the beluga whale, and the fin whale. The humpback whale is noted to have become abundant in the Chukchi Sea in the summer in recent years. The coastal mortality of cetaceans in a 100-km section in the western part of the distribution range of both gray and bowhead whales has been established to average 1.66 and 0.3 whales per year, respectively. Mostly young animals of 1–2 years of age appear to die, the main cause of death of which is predation by killer whales. The most common whales in that area in the summer–autumn period are humpback whales, which at the same time form significant concentrations in the coastal waters during the accumulation of the main food items. Both bowhead and gray whales are much less frequent, found rather irregularly, while despite the relative scarcity of encounters, these species account for the lion's share of all dead cetaceans. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
9. Killer whales (Orcinus orca) hunt, kill and consume the largest fish on Earth, the whale shark (Rhincodon typus).
- Author
-
Pancaldi, Francesca, Ayres, Kathryn A., Gallagher, Austin J., Moskito, James, Williamson, Kelsey C., and Higuera Rivas, Jesús Erick
- Subjects
PREDATORY aquatic animals ,TOP predators ,PREDATION ,FOOD chains ,FINS (Anatomy) ,KILLER whale - Abstract
Killer whales (Orcinus orca) are the apex predator in global oceans, and as such they are afforded access to prey species at all trophic levels and sizes. Due to their enhanced cognitive abilities, they are frequent predators of other ocean giants, including large sharks. Observations of these predator-prey interactions are rare globally; however, records appear to be increasing in recent years, possibly due to increased access to surveillance. Here we present reports of killer whales hunting and preying on the world's largest fish species, the whale shark (Rhincodon typus), by collating and analyzing photo and video footage collected from four unique predation events spanning six years (2018 – 2024) in the southern Gulf of California. Across all events, orcas displayed a seemingly approach to collaboratively hunting and killing whale sharks, characterized by focusing on attacking the pelvic area (claspers and pelvic fins) which exsanguinates the prey and allows access to the lipid-rich liver. Photo identification of the killer whales revealed that an individual adult male "Moctezuma" was engaged in three of the four events, and the females involved in event four had previously been sighted with him. We suggest the potential existence of a specialized pod of elasmobranch-hunting killer whales occurring in the Gulf of California. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
10. Recent surveys of the sea otter (Enhydra lutris) population on Kuril Islands.
- Author
-
Popov, Igor and Iurmanov, Anton
- Subjects
- *
SEA otter , *KILLER whale , *OCEAN waves , *TERRITORIAL waters , *ENDANGERED species - Abstract
Context: Sea otters, an endangered species, require regular assessments of their distribution and abundance. These animals inhabit the coastal waters of the North Pacific, traversing from Japan through the Kurils, southern Kamchatka, Commander and Aleutian Islands, and the coasts of North America, to California. Although populations in America and the Commander Islands have been consistently monitored over recent decades, the same cannot be said for the Kuril Islands. Aim: This study aims to estimate the state of sea otter populations on the Kuril Islands. Methods: The study area encompassed a section of the Kuril archipelago, including Iturup, Urup, Broughton, Chirpoy, and Simushir Islands, surveyed from 2019 to 2023. Sea otters were counted along sections of the coastline, and published sources on other Kuril Islands were analysed. Key results: There are several hundred sea otters within surveyed area, whereas in 1960–1980 ~2000 were reported. The total number of sea otters on the archipelago hardly exceeds 3000. The initial or normal number is not known, but the information on hunting indicates that it was much bigger. Up to the end of 19th century, at least 'one thousand individuals' had been harvested annually over several decades; this means that the total number was at least several tens of thousands. Conclusions: Sea otter populations on the Kuril Islands are in decline, with poaching in the recent past identified as significant contributing factor in a part of the archipelago. Implications: Urgent conservation measures are imperative to address the decline of sea otter populations. What is happening with sea otters in remote unpopulated areas? This question arose during recent expeditions to the Kuril Islands. Sections of shore have been surveyed, revealing a decline in sea otter populations. It is likely that this decline is due to illegal hunting, similar to occurrences in the remote past. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
11. Killer Whale Predation on a Giant Manta Ray (Mobula birostris), a Sicklefin Devil Ray (Mobula tarapacana) and a Tiger Shark (Galeocerdo cuvier) in the Southwest Indian Ocean.
- Author
-
Terrapon, Maeva, Venables, Stephanie K., Lokker, Anthony, Bertrand, Nils, Hooker, Sascha K., and Marshall, Andrea D.
- Subjects
- *
MOBULIDAE , *RAYS (Fishes) , *SHARKS , *INFORMATION resources , *OCEAN - Abstract
Knowledge of killer whale (Orcinus orca) feeding ecology in tropical waters is scarce. In the southwest Indian Ocean, opportunistic sightings provide a valuable source of information to better understand their behaviour, diet and distribution. Here, we compile existing records of killer whale predation on elasmobranchs in the southwest Indian Ocean, including sightings of three undescribed prey species regionally: a giant manta ray (Mobula birostris), a sicklefin devil ray (Mobula tarapacana) and a tiger shark (Galeocerdo cuvier). Documenting such observations is important to increase knowledge on killer whale ecology in the tropics and the cascading impact they might have on prey populations. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
12. Killer whales in the Gulf of Mexico and North Atlantic off the Southeastern United States.
- Author
-
Barry, Kevin P., Mullin, Keith D., Maze-Foley, Katherine, Wilcox Talbot, Lynsey A., Rosel, Patricia E., Soldevilla, Melissa S., Dias, Laura Aichinger, Ramírez-León, M. Rafael, and Litz, Jenny A.
- Subjects
SPERM whale ,SOCIAL structure ,SPRING ,CETACEA ,WHALES ,KILLER whale - Abstract
Killer whales occur in the Gulf of Mexico (GoMex) and the North Atlantic, including off the southeastern United States (SEUS). Data from cetacean surveys during 1990 – 2021 and other sources were combined to assess killer whale biology, including spatial and temporal distribution, social structure, genetics, morphology, acoustics, and predatory behavior. GoMex records occurred predominantly in oceanic waters (>200 m) during spring and summer. SEUS records occurred primarily in winter and spring off the North Carolina region along the shelf-edge and deeper waters, and off the east coast of Florida. Photo-identification analysis of GoMex killer whales resulted in 49 individuals sighted up to seven times with sighting histories up to 26 years, and social analysis provided evidence of long-term relationships up to 16 years. The GoMex genetic samples revealed two mtDNA haplotypes, one of which does not match any outside the GoMex. Most GoMex whales had wide non-faint saddle patches and many had cookiecutter shark scars while no scars were noted on SEUS whales. Three groups recorded in the GoMex made few calls, but a group harassing sperm whales produced many. Cetaceans and tuna are known prey in the GoMex and SEUS, respectively. Directed studies of killer whales in the GoMex areas would be difficult to implement as this species is very rare. It is therefore important to pursue ongoing efforts to collect behavioral, acoustic and any biological samples that will contribute to improve our understanding of the biology and ecology of killer whales in tropical and subtropical regions. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
13. The Racialization of Killer Whales: An Application of Gene-Culture Coevolutionary Theory.
- Author
-
Golding, David
- Subjects
- *
KILLER whale , *NATURAL selection , *CULTURE conflict , *INDIGENOUS peoples , *CETACEA - Abstract
An expanding body of research aims to identify culture in cetaceans, often positing killer whales as an exemplar species. To this end, gene-culture coevolutionary theory provides a conceptual language with which whales are discussed in raciological terms. It renders killer whale ecotypes as discrete cultures that are intrinsically xenophobic and evolutionarily divergent. Such research on whale culture intends to substantiate theories of divergent natural selection between human cultures as well. This effort furthers the essentialism, simultaneously biological and cultural, that has long impelled colonial technoscientific projects of racial typologization. The exchange between the raciologies of humans and killer whales is facilitated by the infrahumanizing frameworks of gene-culture coevolutionary theory that locate whale populations alongside indigenous peoples on a spectrum of cultural simplicity and complexity. At this convergence of the animal and the human, gene-culture coevolutionary theory posits indigenous peoples and killer whales as evidence for social Darwinist theories that dehistoricize and naturalize intercultural conflict and ethnicization. The extension of raciology beyond the human species signals an urgent need to decolonize the biological sciences. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
14. New records of odontocete and mysticete predation by orcas in the Humboldt current system, South Pacific Ocean.
- Author
-
García-Cegarra, Ana M., Oña, Javier, Arancibia, Camilo, Aguilar, Luis, and Toro, Frederick
- Subjects
PREDATORY aquatic animals ,SEA lions ,PERU Current ,MARINE mammals ,KILLER whale ,DOLPHINS ,BOTTLENOSE dolphin - Abstract
Orcas (Orcinus orca) are the top marine predators of the ocean, targeting multiple taxa including teleost fishes, elasmobranchs, seabirds, sea turtles, pinnipeds, odontocetes and other large cetaceans. According to their foraging strategies, genetics, acoustics, and morphology, orcas differentiate into ecotypes. Despite their cosmopolitan distribution, orcas are poorly studied in areas such as the Humboldt Current System of the Southeast Pacific coast. Since 2018 in northern Chile, presumed Type A orcas have been observed foraging on South American sea lions (Otaria byronia), benefiting from the presence of fishing vessels facilitating their hunt. These orcas were observed also pursuing large mixed groups of dusky (Lagenorhynchus obscurus) and long-beaked common dolphins (Delphinus capensis); however, predation on dusky dolphins was not documented. Here, we provide 28 additional sightings of orcas in two upwelling hotspots along northern Chile (15 around the Chañaral, Choros, and Damas Islandsin the Humboldt Penguin National Reserve from 2010-2023 and 13 in the Mejillones Peninsula from 2022-2023) and the first records of orcas effective hunting on dusky dolphins in this area. We present three new observations of orca tooth rake marks on fin whales (Balaenoptera physalus) dorsal fins in northern Chile. Furthermore, we observed the same orcas on two occasions foraging on dusky dolphins and sharing dolphin meat among group members. Overall, these observations suggest that orcas in northern Chile forage on marine mammals, especially on dusky dolphins, and the number of such predation events seems to be increasing near the coast. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
15. The Gallery.
- Subjects
JAPANESE macaque ,URBAN gardens ,RED fox ,KILLER whale ,WILDLIFE photographers - Abstract
The article discusses the Wildlife Photographer of the Year competition, which is organized by the Natural History Museum in London. The competition aims to find exceptional photographs that showcase the beauty and diversity of our planet and our relationship with nature. To commemorate the 60th anniversary of the competition, a new book has been published featuring a collection of the best images from the past six decades. The article also highlights some of the award-winning photographs, including images of animals in their natural habitats and captivating moments captured by photographers from around the world. [Extracted from the article] more...
- Published
- 2024
16. Less ice, more predators: passive acoustic monitoring shows variation in killer whale (Orcinus orca) presence in the U.S. Arctic with declining sea ice.
- Author
-
Kimber, Brynn M., Braen, Eric K., Wright, Dana L., Harlacher, Jenna M., Crance, Jessica L., and Berchok, Catherine L.
- Abstract
Arctic sea ice has provided a historical barrier for killer whale (Orcinus orca) entry, but that barrier is now depleting as the sea ice melts due to global climate change. This study used passive acoustic monitoring to describe changes in broad-scale killer whale presence in the U.S. Arctic associated with declining sea ice. Passive acoustic data were analyzed for killer whale calls from eight monitoring sites throughout the Alaska Chukchi, northern Bering, and western Beaufort seas from 2011 to 2019 and correlated with sea ice coverage. Killer whale acoustic presence was significantly correlated with sea ice coverage in the U.S. Arctic at two sites directly north and south of the Bering Strait (p = 0.04, t7 = − 5.34; p = 0.03, t7 = − 4.42), and increased as sea ice decreased in the North Slope region along the Northern Alaska coast (p < 0.01, t7 = 4.49). We also observed shifts in the spring arrival of killer whale calling over the time period of the study, which correlated with the timing of sea ice retreat. Killer whales shifted their time of arrival an average of 50 days earlier in the North Slope region and 32 days earlier in the Bering Strait region over the study period with 16.2 days (± 6.6 SD) lag between sea ice retreat and the first killer whale detection. These results point to an increased presence of an apex predator in the U.S. Arctic, which has the potential to impact the trophic dynamics of this region. [ABSTRACT FROM AUTHOR] more...
- Published
- 2025
- Full Text
- View/download PDF
17. Causal associations of MICB, CTSA, and MMP9 proteins with oral cancer: Mendelian randomization study.
- Author
-
Dong, Bowen, Hua, Jianlei, Ma, Shengxuan, Wang, Li, Xiao, Haotian, Qiao, Xianghe, Zhao, Rui, and Liu, Yiming
- Subjects
- *
SINGLE nucleotide polymorphisms , *MATRIX metalloproteinases , *ORAL cancer , *KILLER whale , *IMMUNOREGULATION - Abstract
Oral cancer (ORCA) is the most prevalent histological subtype of oral malignancies in which immune modulation is relevant. The goal of this work was to employ Mendelian randomization (MR) to investigate the causal connection between the immune-related proteins MICB, CTSA, MMP9, and ORCA. The Open GWAS database of the Integrative Epidemiology Unit (IEU) was accessed to collect GWAS data for ORCA (ieu-b-4961), MICB (prot-a-1898), CTSA (prot-a-717) and MMP9 (prot-a-1921). From 372,373 samples, the ORCA dataset comprises 7,723,107 single nucleotide polymorphisms (SNPs). MICB, CTSA, and MMP9 all have 10,534,735 SNPs and 3,301 sample sizes. Then, the primary SVMR implementation approaches were weighted mode, simple mode, inverse variance weighted (IVW), weighted median, and MR-Egger. IVW was the most effective technique. A sensitivity study was also carried out to assess the correctness of SVMR data, with special focus devoted to heterogeneity, horizontal pleiotropy, and Leave-One-Out (LOO). MVMR was eventually implemented as well. A Mendelian randomization analysis of the three exposure factors in the dataset (ieu-b-94, ebi-a-GCST012237) was also performed to validate the study results. According to the SVMR results, there was a noteworthy causal interaction between ORCA and MICB (P = 0.0014), MMP9 (P = 0.0343), and CTSA (P = 0.0003). Furthermore, odds ratios (ORs) values revealed that MMP9 (OR = 1.0005) was an ORCA risk factor, whereas MICB (OR = 0.9994) and CTSA (OR = 0.9993) were security factors. The robustness of the SVMR findings was confirmed by the p-values of the heterogeneity and horizontal pleiotropy, both of which were greater than 0.05. The MVMR result did not affect any of the safety or hazard features of these three exposure factors. However, the P value for MMP9 was greater than 0.05, implying that MICB and CTSA may have a greater influence on ORCA than MMP9. The validation outcomes in both datasets harmonized with the findings from previous research, thereby solidifying the reliability of results. Our investigation provided a crucial resource for further research on the subject by demonstrating a causal relationship between ORCA and MICB, CTSA, and MMP9. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
18. Effects of pre‐treatment, historical age, and sample characteristics on the stable isotope analyses of killer whale (Orcinus orca) bone.
- Author
-
Bowen, Kelly R. and Kurle, Carolyn M.
- Subjects
- *
STABLE isotope analysis , *KILLER whale , *MASS spectrometers , *DEMINERALIZATION , *CETACEA - Abstract
Rationale: Stable isotope analysis of bone provides insight into animal foraging and allows for ecological reconstructions over time, however pre‐treatment is required to isolate collagen. Pre‐treatments typically consist of demineralization to remove inorganic components and/or lipid extraction to remove fats, but these protocols can differentially affect stable carbon (δ13C) and nitrogen (δ15N) isotope values depending on the chemicals, tissues, and/or species involved. Species‐specific methodologies create a standard for comparability across studies and enhance understanding of collagen isolation from modern cetacean bone. Methods: Elemental analyzers coupled to isotope ratio mass spectrometers were used to measure the δ13C and δ15N values of powdered killer whale (Orcinus orca) bone that was intact (control) or subjected to one of three experimental conditions: demineralized, lipid‐extracted, and both demineralized and lipid‐extracted. Additionally, C:N ratios were evaluated as a proxy for collagen purity. Lastly, correlations were examined between control C:N ratios vs. historical age and control C:N ratios vs. sample characteristics. Results: No significant differences in the δ15N values were observed for any of the experimental protocols. However, the δ13C values were significantly increased by all three experimental protocols: demineralization, lipid extraction, and both treatments combined. The most influential protocol was both demineralization and lipid extraction. Measures of the C:N ratios were also significantly lowered by demineralization and both treatments combined, indicating the material was closer to pure collagen after the treatments. Collagen purity as indicated via C:N ratio was not correlated with historical age nor sample characteristics. Conclusions: If only the δ15N values from killer whale bone are of interest for analysis, no pre‐treatment seems necessary. If the δ13C values are of interest, samples should be both demineralized and lipid‐extracted. As historical age and specimen characteristics are not correlated with sample contamination, all samples can be treated equally. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
19. Prevalence of Chinook salmon is higher for southern than for northern resident killer whales in summer hot-spot feeding areas.
- Author
-
Saygili, Burak and Trites, Andrew W.
- Subjects
- *
KILLER whale , *CHINOOK salmon , *FISH declines , *PREY availability , *FOOD shortages - Abstract
Differences in the availability of prey may explain the low numbers of southern resident killer whales and the increase in northern resident killer whales in British Columbia and Washington State. However, in-situ data on the availability of their preferred prey (Chinook salmon, Oncorhynchus tshawytscha) in the core feeding areas used by these two populations of fish-eating killer whales have been lacking to test this hypothesis. We used multi-frequency echosounders (38, 70, 120, and 200 kHz) to estimate densities of adult Chinook (age-4+, > 81 cm) within 16 hot-spot feeding areas used by resident killer whales during summer 2020 in the Salish Sea and North Island Waters. We found Chinook were generally concentrated within 50 m from the bottom in the deep waters, and tended to be absent near the surface in the shallow waters (< 50 m). In general, the densities of Chinook we encountered were highest as the fish entered the Salish Sea (from Swiftsure Bank in the south) and Johnstone Strait (from Queen Charlotte Strait to the north)—and declined as fish migrated eastward along the shoreline of Vancouver Island. Median densities of Chinook for all sampled areas combined were 0.4 ind.·1000 m−2 in northern resident foraging areas, and 0.9 ind.·1000 m−2 in southern resident killer whale areas (p < 0.05, Mann–Whitney U test). Thus, Chinook salmon were twice as prevalent within the hot-spot feeding areas of southern versus northern resident killer whales. This implies that southern resident killer whales have greater access to Chinook salmon compared to northern residents during summer—and that any food shortage southern residents may be encountering is occurring at other times of year, or elsewhere in their range. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
20. Males miss and females forgo: Auditory masking from vessel noise impairs foraging efficiency and success in killer whales.
- Author
-
Tennessen, Jennifer B., Holt, Marla M., Wright, Brianna M., Hanson, M. Bradley, Emmons, Candice K., Giles, Deborah A., Hogan, Jeffrey T., Thornton, Sheila J., and Deecke, Volker B.
- Subjects
- *
AUDITORY masking , *KILLER whale , *FORAGING behavior , *TERRITORIAL waters , *OCEAN acidification - Abstract
Understanding how the environment mediates an organism's ability to meet basic survival requirements is a fundamental goal of ecology. Vessel noise is a global threat to marine ecosystems and is increasing in intensity and spatiotemporal extent due to growth in shipping coupled with physical changes to ocean soundscapes from ocean warming and acidification. Odontocetes rely on biosonar to forage, yet determining the consequences of vessel noise on foraging has been limited by the challenges of observing underwater foraging outcomes and measuring noise levels received by individuals. To address these challenges, we leveraged a unique acoustic and movement dataset from 25 animal‐borne biologging tags temporarily attached to individuals from two populations of fish‐eating killer whales (Orcinus orca) in highly transited coastal waters to (1) test for the effects of vessel noise on foraging behaviors—searching (slow‐click echolocation), pursuit (buzzes), and capture and (2) investigate the mechanism of interference. For every 1 dB increase in maximum noise level, there was a 4% increase in the odds of searching for prey by both sexes, a 58% decrease in the odds of pursuit by females and a 12.5% decrease in the odds of prey capture by both sexes. Moreover, all but one deep (≥75 m) foraging attempt with noise ≥110 dB re 1 μPa (15–45 kHz band; n = 6 dives by n = 4 whales) resulted in failed prey capture. These responses are consistent with an auditory masking mechanism. Our findings demonstrate the effects of vessel noise across multiple phases of odontocete foraging, underscoring the importance of managing anthropogenic inputs into soundscapes to achieve conservation objectives for acoustically sensitive species. While the timescales for recovering depleted prey species may span decades, these findings suggest that complementary actions to reduce ocean noise in the short term offer a critical pathway for recovering odontocete foraging opportunities. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
21. Killer Whale (Orcinus orca) Harassment on Humpback Whales (Megaptera novaeangliae) in Offshore Brazilian Waters.
- Author
-
Athayde, Aline, Pereira Bragança, Sara, and Siciliano, Salvatore
- Subjects
- *
KILLER whale , *AQUATIC mammals , *DRILLING platforms , *MARINE mammals , *SEA lions , *WHALES , *HUMPBACK whale - Abstract
This article discusses an observation of killer whales harassing humpback whales in offshore Brazilian waters. The observation took place in August 2023 and involved killer whales chasing and surrounding the humpback whales, with instances of physical contact. The behavior suggests that the killer whales may be targeting the humpback whales as prey. While fatal attacks are rare, there have been reports of such attacks in different regions of the world. The article also mentions that killer whales generally target smaller or younger whales during attacks. The observations provide new insights into the interactions between killer whales and humpback whales in the region, but it is unclear if these interactions have increased or are being recorded more frequently due to improved technology. This collection of scientific articles explores various aspects of killer whale interactions with other marine species in different regions, providing valuable insights into their behavior and ecological implications. These findings contribute to our understanding of the complex relationships between marine species and can inform conservation efforts. [Extracted from the article] more...
- Published
- 2024
- Full Text
- View/download PDF
22. Dietary plasticity and broad North Atlantic origins inferred from bulk and amino acid‐specific δ15N and δ13C favour killer whale range expansions into Arctic waters.
- Author
-
Matthews, Cory J. D., Yarnes, Chris T., Lefort, Kyle J., Edkins, Tera L., Kiszka, Jeremy J., and Ferguson, Steven H.
- Subjects
- *
AMINO acid analysis , *STABLE isotope analysis , *MARINE mammals , *BALEEN whales , *GLUTAMIC acid , *KILLER whale , *THREONINE - Abstract
Killer whales (Orcinus orca) occur seasonally in the eastern Canadian Arctic (ECA), where their range expansion associated with declining sea ice have raised questions about the impacts of increasing killer whale predation pressure on Arctic‐endemic prey.We assessed diet and distribution of ECA killer whales using bulk and compound‐specific stable isotope analysis (CSIA) of amino acids (AA) of 54 skin biopsies collected from 2009 to 2020 around Baffin Island, Canada.Bulk ECA killer whale skin δ15N and δ13C values did not overlap with potential Arctic prey after adjustment for trophic discrimination, and instead reflected foraging history in the North Atlantic prior to their arrival in the ECA. Adjusted killer whale stable isotope (SI) values primarily overlapped with several species of North Atlantic baleen whales or tuna. Amino acid (AA)‐specific δ15N values indicated the ECA killer whales fed primarily on marine mammals, having similar glutamic acid δ15N–phenylalanine δ15N (δ15NGlx‐Phe) and threonine δ15N (δ15NThr) as mammal‐eating killer whales from the eastern North Pacific (ENP) that served as a comparative framework. However, one ECA whale grouped with the fish‐eating ENP ecotype based δ15NThr.Distinctive essential AA δ13C of ECA killer whale groups, along with bulk SI similarity to killer whales from different regions of the North Atlantic, indicates different populations converge in Arctic waters from a broad source area. Generalist diet and long‐distance dispersal capacity favour range expansions, and integration of these insights will be critical for assessing ecological impacts of increasing killer whale predation pressure on Arctic‐endemic species. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
23. Killer whales in the Gulf of Mexico and North Atlantic off the Southeastern United States
- Author
-
Kevin P. Barry, Keith D. Mullin, Katherine Maze-Foley, Lynsey A. Wilcox Talbot, Patricia E. Rosel, Melissa S. Soldevilla, Laura Aichinger Dias, M. Rafael Ramírez-León, and Jenny A. Litz
- Subjects
acoustics ,genetics ,Gulf of Mexico ,killer whale ,morphology ,North Atlantic Ocean ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Killer whales occur in the Gulf of Mexico (GoMex) and the North Atlantic, including off the southeastern United States (SEUS). Data from cetacean surveys during 1990 – 2021 and other sources were combined to assess killer whale biology, including spatial and temporal distribution, social structure, genetics, morphology, acoustics, and predatory behavior. GoMex records occurred predominantly in oceanic waters (>200 m) during spring and summer. SEUS records occurred primarily in winter and spring off the North Carolina region along the shelf-edge and deeper waters, and off the east coast of Florida. Photo-identification analysis of GoMex killer whales resulted in 49 individuals sighted up to seven times with sighting histories up to 26 years, and social analysis provided evidence of long-term relationships up to 16 years. The GoMex genetic samples revealed two mtDNA haplotypes, one of which does not match any outside the GoMex. Most GoMex whales had wide non-faint saddle patches and many had cookiecutter shark scars while no scars were noted on SEUS whales. Three groups recorded in the GoMex made few calls, but a group harassing sperm whales produced many. Cetaceans and tuna are known prey in the GoMex and SEUS, respectively. Directed studies of killer whales in the GoMex areas would be difficult to implement as this species is very rare. It is therefore important to pursue ongoing efforts to collect behavioral, acoustic and any biological samples that will contribute to improve our understanding of the biology and ecology of killer whales in tropical and subtropical regions. more...
- Published
- 2024
- Full Text
- View/download PDF
24. Close listening.
- Author
-
Gardiner, Bryan
- Subjects
- *
UNDERWATER noise , *WHALING , *SOUND recordings , *UNDERWATER acoustics , *KILLER whale , *EAR , *ELEPHANTS , *INNER ear , *BATS - Abstract
Three books explore the wonders of sound in different contexts. "The Great Animal Orchestra" by Bernie Krause introduces the concept of "biophony," the collective sounds made by nonhuman organisms in a specific biome. Caspar Henderson's "A Book of Noises" adds the category of "cosmophony," or the sounds of the cosmos, to Krause's framework. Amorina Kingdon's "Sing Like Fish" focuses on the importance of sound in underwater life and the need for humans to pay attention to the impact of their own noise. Larry Sherman and Dennis Plies' "Every Brain Needs Music" delves into the neuroscience of making and listening to music. These books highlight the significance of sound in understanding and appreciating the world around us. [Extracted from the article] more...
- Published
- 2024
25. EMBRACING ORCAS.
- Author
-
McGhie, Sophia and Jaimet, Kate
- Subjects
- *
BLUE whale , *KILLER whale , *PREDATORY aquatic animals , *MARINE mammals , *ABORIGINAL Canadians , *FASTING - Published
- 2024
26. My Own Way to Shine.
- Author
-
HARTKE, LYNNE
- Subjects
KILLER whale ,TEACHERS' assistants ,RESCUE dogs ,DOG rescue ,SNOWMAKING - Abstract
This article from Guideposts tells the story of Lynne, the wife of a pastor and mayor, who often feels overshadowed by her husband's outgoing personality. Lynne struggles with feelings of insecurity and a desire to be more extroverted and popular. However, after a series of events, including reading to a special needs classroom, Lynne realizes the importance of being true to herself and embracing her introverted nature. She learns to appreciate her own unique qualities and finds contentment in being herself. [Extracted from the article] more...
- Published
- 2024
27. Boating Around Whales: Southern Resident Killer Whales Regulations for 2024.
- Author
-
DAVIS, TOM
- Subjects
KILLER whale ,SEA lions ,SALMON fishing ,YOUNG adults ,AUTUMN - Abstract
This article focuses on the regulations surrounding boating around Southern Resident Killer Whales (SRKWs) in 2024. It acknowledges the decline in the SRKW population and the ongoing efforts to aid their recovery. The article acknowledges the confusion surrounding the regulations and emphasizes the importance of understanding them to avoid legal violations. It highlights the significance of distinguishing between resident and transient killer whales, suggesting visual observation as the most straightforward method to identify SRKWs. The text provides information on fishing regulations and protective measures for killer whales (SRKWs) in British Columbia, including restrictions on recreational and commercial salmon fishing in specific areas and time periods. It also mentions speed reduction zones and vessel distance avoidance regulations to safeguard the whales. The article discusses both mandatory and voluntary regulations, as well as the necessity for consultation with affected groups and coastal communities. It recommends that boaters and anglers familiarize themselves with Canadian and US rules regarding SRKWs. [Extracted from the article] more...
- Published
- 2024
28. COASTAL PASSES: Mastering the passes of the Southern Gulf Islands.
- Author
-
Vipond, Anne and Kelly, William
- Subjects
PATROL boats ,TIDAL currents ,RIP currents ,STRAITS ,KILLER whale - Abstract
This article from Pacific Yachting provides valuable information for boaters navigating the passes in the Southern Gulf Islands. It emphasizes the importance of understanding tides and currents, using proper charts and tide tables, and being aware of ferry traffic. The article specifically mentions Boundary Pass, Active Pass, and East Point as areas with strong currents and potential hazards. It also mentions historical and geographical details, such as the use of Boat Passage by rumrunners during prohibition and the construction of the lighthouse at Georgia Point. The authors of the article have written a book called "Best Anchorages of the Passage" for further information on the subject. [Extracted from the article] more...
- Published
- 2024
29. Navigating ‘Orca Alley’.
- Author
-
Stickland, Katy
- Subjects
KILLER whale ,ECHOLOCATION (Physiology) ,TOOTHED whales ,IDENTIFICATION photographs - Abstract
Sailors navigating the Atlantic Iberian coast are facing a new challenge with the presence of orcas, also known as killer whales. These encounters have resulted in damage to numerous vessels and the sinking of several boats. A sub-group of about 15 orcas has learned and passed on the behavior of bumping into boats and touching their rudders. These interactions are more common between June and September, and sailors are advised to stay in shallower waters and close to the shore to minimize the risk. The Cruising Association is working with marine scientists to collect and share data on the orcas' movements, and resources are available to help sailors avoid these encounters. The Spanish and Portuguese governments are also providing advice and information to sailors, and a new acoustic deterrent device is being tested as a potential solution. The article includes a personal account of a family's encounter with orcas, where their boat was repeatedly rammed, causing damage and disabling the boat. The family eventually reached a port for repairs. The author does not take a position on whether the orcas' behavior was playful or aggressive. [Extracted from the article] more...
- Published
- 2024
30. Using passive acoustics to identify a quiet winter foraging refuge for an endangered beluga whale population in Alaska.
- Author
-
Castellote, Manuel, Gill, Verena A., Garner, Christopher D., Gilstad, Andrea J., Hou, Benjamin X., Brewer, Arial M., and Knoth, Jessica M.
- Subjects
KILLER whale ,HARBOR porpoise ,AUDITORY masking ,ANTHROPOGENIC effects on nature ,NATURAL gas in submerged lands ,WHITE whale ,HUMPBACK whale - Abstract
Cook Inlet beluga (CIB), Delphinapterus leucas, have not recovered from subsistence overharvest despite conservation efforts initiated in 2000. Reasons for this lack of recovery are still unclear with anthropogenic noise identified as a high threat in this population's recovery plan. Baseline information on CIB habitat use and soundscape characterization is crucial in evaluating impacts from anthropogenic activities. Using passive acoustic monitoring, we documented the seasonality and foraging occurrence of CIB, together with killer whale (Orcinus orca), harbor porpoise (Phocoena phocoena) and humpback whale (Megaptera novaeangliae), for one year in Chinitna and Tuxedni bays and rivers, two historically important but recently overlooked areas of their critical habitat in western lower Cook Inlet, Alaska. This area's ecological interest converges with planned mining, marine renewable energy, offshore oil and gas production, and commercial shipping. Results revealed higher presence of harbor porpoise, killer whale, and humpback whale in Chinitna compared to Tuxedni but much lower CIB presence. CIB were not detected in Chinitna Bay but were in the river on 21 days September-February and one day in June. However, CIB were never detected feeding in Chinitna River. CIB acoustic crypsis and preferential use of very shallow habitat in Chinitna revealed a perceived predation risk from killer whales. In contrast, CIB were recorded foraging in both Tuxedni Bay and River and were detected September-April on 127 days making it an important winter foraging ground. Low levels of anthropogenic noise disturbance were quantified in both bays making them some of the most undisturbed sections of their critical habitat, but at the same time highly sensitive to further noise disturbance. Commercial shipping was the main noise source likely causing acoustic disturbance to CIB due to communication masking despite current low levels of temporal overlap with beluga presence. We recommend that applicable regulators consider restricting high sound producing anthropogenic activities in and adjacent to Tuxedni Bay from September 1st to May 15th when CIB are actively using this area. Managing future anthropogenic activities to minimize habitat degradation and acoustic disturbance in this winter foraging refuge will be a key component to support the recovery of this endangered population. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
31. Trip Pattern Impact of Electric Vehicles in Optimized Power Production using Orca Algorithm.
- Author
-
Afandi, Arif Nur, Zulkifli, Shamsul Aizam, Korba, Petr, Segundo Sevilla, Felix Rafael, Handayani, Anik Nur, Aripriharta, Wibawa, Aji Presetya, and Afandi, Farrel Candra Winata
- Subjects
- *
KILLER whale , *ALGORITHMS , *LEISURE , *BUSES , *SHOPPING - Abstract
Power systems are run by combining different energy producers while the demand serves as the system's energy user and covers all of the non-flexible and flexible loads, including electric vehicles (EVs). This study investigated the trip pattern impact of EVs, utilizing the Orca Algorithm (OA), in optimizing power production, applied to the IEEE-62 bus system as a model. Considering one-way and two-way trips over several categories of typical roads, the mobility of 14,504 EVs, divided into four driving patterns (Mobility 1-4), was estimated. Approximately 2,933 EVs traveled for working/business/study purposes, 3,862 EVs traveled for service/shopping purposes, approximately 5,376 EVs traveled for leisure purposes, while 2,334 EVs traveled for other reasons. The system had a total demand of 18,234.9 MVA, including 3,352.8 MW for electric vehicles and 14,151.5 MW for non-flexible loads. The EVs traveled a total of 119,018 km in Mobility 1, 141,799 km in Mobility 2, 184,614 km in Mobility 3, and 82,637 km in Mobility 4. The power produced was also used to charge the EVs during trips. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
32. Geographic Distribution of North Atlantic Humpback Whales (Megaptera novaeangliae) with Fluke Scars Caused by Killer Whales (Orcinus orca).
- Author
-
Koilpillai, Hana A., Basran, Charla J., Berrow, Simon, Broms, Fredrik, Chosson, Valerie, Gowans, Shannon, Jones, Lindsey S., Kempen, Reg, López-Suárez, Pedro, Magnúsdóttir, Edda, Massett, Nick, Prince, Kris, Rasmussen, Marianne H., Robbins, Jooke, Sears, Richard, Simard, Peter, Simon, Malene, Whooley, Pádraig, and Wenzel, Frederick W. more...
- Subjects
- *
HUMPBACK whale , *SCARS , *MATING grounds , *KILLER whale , *ANIMAL migration , *SAMPLE size (Statistics) - Abstract
Although killer whale (Orcinus orca) predation on humpback whales (Megaptera novaeangliae) is rarely witnessed, resultant scars on humpback flukes provide evidence of non-lethal interactions. Humpback whale photo-identification catalogs from the North Atlantic were used to evaluate humpback flukes (n = 10,957) for the presence and severity of killer whale scarification (e.g., rake marks, teeth indentations, missing tissue). Flukes were coded as none, light, moderate, or severe based on the extent of scarring. Even with increased sample sizes, especially for Norway and Iceland, the distribution of high-latitude humpbacks with killer whale scarring was consistent with prior studies: Atlantic Canada (21.7%), West Greenland (15.5%), Gulf of Maine (13.5%), Iceland (combined with East Greenland, 9.3%), and Norway (7.9%). For the first time, scarring rates are presented based on data from Ireland, Scotland, and England (11.0%) as well. Scarring frequencies generally differed between the eastern and western North Atlantic despite the co-occurrence of all migrating humpbacks in low-latitude breeding grounds, suggesting the occurrence of killer whale interactions in the distinct feeding grounds or along northward migration routes. While it was not possible to determine exactly where these interactions took place, the likelihood of a killer whale encounter and subsequent scar acquisition was greatest for humpbacks that feed in Atlantic Canada. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
33. Observations of Attacks on Sei and Fin Whales by Killer Whales in Magellanic Sub-Antarctic Waters, Chile.
- Author
-
Schüttler, Elke, Gañan, Melisa, Barroso, Omar, Contador, Tamara, Illanes, Diego, Muñoz-Araya, Gabriel, Palma, María-José, Pérez-Álvarez, María-José, Sepúlveda, Maritza, and Rendoll-Cárcamo, Javier
- Subjects
- *
WHALES , *KILLER whale , *ANIMAL diversity , *SPERM whale , *BLUE whale , *BALEEN whales , *HUMPBACK whale - Abstract
This article discusses observations of killer whale attacks on sei and fin whales in the Magellanic Sub-Antarctic Waters of Chile. The attacks occurred between March 2020 and April 2021 and resulted in the death of the whales. The researchers were able to identify one female killer whale involved in three of the attacks, which is relatively rare. The study emphasizes the need for further research on the trophic ecology and dietary plasticity of killer whales in the area. Additionally, a collection of articles and studies on killer whale behavior, diet, and interactions with other marine species is provided. [Extracted from the article] more...
- Published
- 2024
- Full Text
- View/download PDF
34. The effect of formation swimming on tailbeat and breathing frequencies in killer whales.
- Author
-
Spina, Federica, Weiss, Michael N., Croft, Darren P., Luschi, Paolo, Massolo, Alessandro, and Domenici, Paolo
- Subjects
WHALE behavior ,TOOTHED whales ,SOCIAL hierarchies ,CETACEA ,WHALES - Abstract
In many aquatic taxa, formation traveling can reduce the energetic expenditure of locomotion by exploiting the vorticity trails shed by neighbors or through drafting. Cetaceans, especially odontocetes, often swim in groups; nevertheless, the possibility that whales gain energetic benefits from swimming in formation remains poorly studied, apart from mother-calf pairs. Between June and September in 2019 and 2021, we recorded aerial videos of Southern Resident killer whales (Orcinus orca) in the Salish Sea (USA) travelling in groups. We estimated whale tailbeat and breathing frequencies as proxies of the relative energetic costs of swimming, and tested the effect of swimming speed, relative positioning (e.g., leaders, whales in the middle of groups, or followers), sex and estimated size on these observed proxies. Our results reveal a complex relationship between physical characteristics, relative positioning, and energetic proxies. Intervals between respiration lasted longer in large-sized trailing individuals, but the overall breathing frequency was similar for all whales regardless of their position. The tailbeat frequency was mainly associated to whale sex, size, and swimming speed; in addition, tailbeat frequency showed a decreasing trend as the number of individuals in the formation increased. We found moderate evidence that position-based energetic effects may be present in the formation swimming of killer whales, and it is likely that additional factors such as social ties and hierarchies, play a key role in determining individual positioning in travelling groups. Significance: Swimming in formation has been extensively studied in fish and other aquatic animals and has been documented to provide energetic advantages. Our understanding of the potential energetic benefits of wild cetacean formation swimming has been constrained by the difficulties of studying the movement of whale groups from traditional observation platforms. In recent years, non-invasive observations of cetaceans using unoccupied aerial systems have significantly improved the observation of these species in the wild, providing an exciting opportunity to better understand their behaviors and habits. Our results show a tendency for formation swimming to affect two energetic proxies (tailbeat frequency and the duration of underwater intervals between surfacing events). The results of this study set the stage for further research to identify the multiple determinants affecting killer whale formation swimming which go beyond purely energetic advantages, e.g. social relationships. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
35. Independent Task Scheduling in Cloud Computing Environment using Modified Orca Optimizer.
- Author
-
Masadeh, Raja, sharieh, Ahmad, Abu-Jazoh, Mai, Alshqurat, Kholoud, Masadeh, Esra, and Alsharman, Nesreen
- Subjects
OPTIMIZATION algorithms ,VIRTUAL machine systems ,METAHEURISTIC algorithms ,PRODUCTION scheduling ,KILLER whale - Abstract
Cloud computing (CC) has become a hot study area as a result of the rapid development and movement of many services to the cloud environment. In order to minimize makespan, the task scheduling mechanism must allocate tasks to appropriate and obtainable virtual machines (VMs). In this research, a modified Orca optimization algorithm (MOOA) and a task scheduling method for CC based on MOOA are presented. The simulation results showed that MOOA scheduler outperformed other state-of-the-art schedulers in terms of makespan. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
36. Humpback whales inflate throat pleats to rub against the seafloor for skin maintenance.
- Author
-
Stevenson, Andrew and Werth, Alexander J.
- Subjects
HUMPBACK whale ,BARNACLES ,BALEEN whales ,WHITE whale ,KILLER whale ,HUMPBACK whale behavior ,SPERM whale - Abstract
Humpback whales in Bermuda have been observed engaging in a unique behavior of expanding their oral pouches and rubbing them against the seafloor. This behavior is believed to be a method of skin maintenance in areas where barnacles and whale lice congregate. The whales were observed swimming together, often in pairs, and descending into sand holes to rub their expanded pouches against the bottom. This behavior is different from feeding and may serve as a way for the whales to exfoliate and clean hard-to-reach areas of their bodies. Further research is needed to fully understand this behavior. [Extracted from the article] more...
- Published
- 2024
- Full Text
- View/download PDF
37. Orca (Orcinus orca) and shark predator-prey interactions within Cabo Pulmo National Park in the Gulf of California, Mexico.
- Author
-
Ayres, Kathryn A., Gallagher, Austin J., and Erick Higuera-Rivas, Jesu´ s
- Subjects
KILLER whale ,PREDATION ,SHARKS ,CHONDRICHTHYES ,MARINE mammals ,NATIONAL parks & reserves ,WHITE shark - Abstract
Orcas (Orcinus orca) have a worldwide distribution and as apex predators feed on a wide variety of prey, including marine mammals, seabirds, sea turtles, cephalopods, teleost fish and elasmobranchs. Historically, there have been few observations of orca predation on large elasmobranch species nor are they commonly identified in the stomach contents of deceased orcas. In recent years there has been an increase in observational records of orca predation, such as on white sharks (Carcharodon carcharias) in South Africa, which could indicate that elasmobranchs serve a greater importance in their diet than previously considered. These events are often documented by members of the public due to the development and affordability of innovative cameras, including the use of the drones (unoccupied aerial vehicles). Here we describe new predator-prey interactions between orcas and large shark species in Cabo Pulmo National Park (CPNP), a small no-take marine protected area located in the Gulf of California. In this paper, we were able to successfully identify individuals from the described orca pods in the region; specifically, the same individuals hunting sharks over a period of nearly two years. We discuss the potential implications of these new ecological interactions, given the importance of tourism to sustain the management of CPNP, as cascading impacts have been documented elsewhere in light of orca predations on sharks. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
38. Cetacean Stranding Response Program and Spatial–Temporal Analysis in Taiwan, 1994–2018.
- Author
-
Chou, Lien-Siang, Yao, Chiou-Ju, Wang, Ming-Chih, Chi, Wei-Lien, Ho, Yun, and Yang, Wei-Cheng
- Subjects
- *
CETACEA , *DOLPHINS , *KILLER whale , *BOTTLENOSE dolphin , *DATABASES , *PORPOISES - Abstract
Simple Summary: This study reviews the development of the cetacean stranding response program in Taiwan from 1994 to 2018, and examines 1320 stranding events involving 1698 animals across at least 27 species. The stranding rates have increased significantly over the years, with a notable rise in annual events from 16 to over 90. Seasonal variation demonstrates higher stranding rates during the northeastern monsoon season. The study highlights the spatial distribution of strandings, with the highest frequency in northern Taiwan and mass strandings predominantly in the southwest. Additionally, live strandings accounted for 29.5% of events and 38.9% of animals. The rescue and rehabilitation of some individuals have been conducted, and 15 individuals have been released since 2000. The findings underscore the diversity and stranding patterns of cetaceans around Taiwanese waters, and provide valuable information for developing conservation strategies in the western Pacific. A national cetacean stranding response program in Taiwan has evolved significantly in the past three decades. Initially co-ordinated by National Taiwan University from 1994, the program transitioned to the Taiwan Cetacean Society in 1999, and local governments took on a more prominent role after 2009. A comprehensive stranding database (1994–2018) has been maintained, which documented 1320 stranding events involving 1698 animals from at least 27 species. The most commonly stranded species include finless porpoises, bottlenose dolphins, Kogia spp., and Risso's dolphins. The stranding rates varied annually and seasonally, with increases noted from an average of 16 events per year for the first 3 years to 44–58 events per year between 1997 and 2015, and a sharp rise to over 90 events per year for the period of the last three years. Seasonal variations were also significant, with higher stranding rates during the northeastern monsoon (NEM, October to next April) than that during southwestern monsoon (SWM, May to September). From the aspect of distribution, more frequent and even strandings occurred along the coast of northern Taiwan, while mass strandings were concentrated in the southwestern counties during NEM. Among all strandings, 390 events (29.5%) and 660 animals (38.9%) were live ones. Under great effort in rescuing and rehabilitating 52 cases, 15 cetacean individuals have been released since 2000. Additionally, there have been 56 mass strandings involving at least 11 species since 1994, predominated by pygmy killer whales, particularly during the NEM season along the southwest coast. This study not only contributes to our understanding of the stranding patterns and diversity of the cetaceans in Taiwan, but also provides valuable insights for future conservation strategies on cetaceans in the western Pacific. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
39. Comparison of infrared thermography of the blowhole mucosa with rectal temperatures in killer whales (Orcinus orca).
- Author
-
Russell, Jennifer P., St. Germain, Micah, Osborn, Steve D., Schmitt, Todd L., Herrick, Kelsey E. S., and Robeck, Todd
- Subjects
THERMOGRAPHY ,INFRARED imaging ,WATER temperature ,ATMOSPHERIC temperature ,MUCOUS membranes ,KILLER whale - Abstract
Killer whales are an important sentinel species and developing non-invasive methods of health assessments might provide insight for understanding how wildlife health is influenced by ecosystem change. Rectal temperature (RT) is a proxy for core body temperature in managed-care cetaceans, however, this measurement is impractical for free-ranging cetaceans and infrared imaging has been suggested as an alternative. The aim of the current study was to prospectively compare infrared thermography of the blowhole to rectal temperatures in killer whales, as well as establish a healthy range for rectal temperature using retrospective data. Infrared video was recorded from the blowhole of thirteen healthy killer whales in managed care, immediately followed by rectal temperature measurement. Repeated measures Bland-Altman analysis revealed blowhole temperature (BHT) had a bias of -1.28°C from RT. Considerable proportional bias was observed with agreement between measurements improving as mean temperature increased. RT positively associated with air temperature, and inversely associated with body mass. BHT was not significantly affected by sex or body mass but was significantly affected by water temperature and air temperature. Retrospective analysis from eighteen killer whales (n = 3591 observations) was performed to generate expected RT ranges, partitioning out for sex and body mass. Given the proportional bias observed with Bland Altman analysis, BHT cannot currently be recommended as a measurement for absolute core body temperature, however infrared thermography of the blowhole remains a promising tool for health assessment of free-ranging killer whale populations, as it may serve as a non-contact screening tool to detect pyrexic animals within a group. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
40. Climate change introduces threatened killer whale populations and conservation challenges to the Arctic.
- Author
-
Garroway, Colin J., de Greef, Evelien, Lefort, Kyle J., Thorstensen, Matt J., Foote, Andrew D., Matthews, Cory J. D., Higdon, Jeff W., Kucheravy, Caila E., Petersen, Stephen D., Rosing‐Asvid, Aqqalu, Ugarte, Fernando, Dietz, Rune, and Ferguson, Steven H. more...
- Subjects
- *
WILDLIFE conservation , *KILLER whale , *TUNDRAS , *CLIMATE change , *TOP predators , *GREY literature - Abstract
The Arctic is the fastest‐warming region on the planet, and the lengthening ice‐free season is opening Arctic waters to sub‐Arctic species such as the killer whale (Orcinus orca). As apex predators, killer whales can cause significant ecosystem‐scale changes. Setting conservation priorities for killer whales and their Arctic prey species requires knowledge of their evolutionary history and demographic trajectory. Using whole‐genome resequencing of 24 killer whales sampled in the northwest Atlantic, we first explored the population structure and demographic history of Arctic killer whales. To better understand the broader geographic relationship of these Arctic killer whales to other populations, we compared them to a globally sampled dataset. Finally, we assessed threats to Arctic killer whales due to anthropogenic harvest by reviewing the peer‐reviewed and gray literature. We found that there are two highly genetically distinct, non‐interbreeding populations of killer whales using the eastern Canadian Arctic. These populations appear to be as genetically different from each other as are ecotypes described elsewhere in the killer whale range; however, our data cannot speak to ecological differences between these populations. One population is newly identified as globally genetically distinct, and the second is genetically similar to individuals sampled from Greenland. The effective sizes of both populations recently declined, and both appear vulnerable to inbreeding and reduced adaptive potential. Our survey of human‐caused mortalities suggests that harvest poses an ongoing threat to both populations. The dynamic Arctic environment complicates conservation and management efforts, with killer whales adding top‐down pressure on Arctic food webs crucial to northern communities' social and economic well‐being. While killer whales represent a conservation priority, they also complicate decisions surrounding wildlife conservation and resource management in the Arctic amid the effects of climate change. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
41. Killer whale respiration rates.
- Author
-
McRae, Tess M., Volpov, Beth L., Sidrow, Evan, Fortune, Sarah M. E., Auger-Méthé, Marie, Heckman, Nancy, and Trites, Andrew W.
- Subjects
- *
OXYGEN consumption , *RESPIRATION , *KILLER whale , *HIDDEN Markov models , *TOP predators , *CALORIC content of foods , *CETACEA - Abstract
Measuring breathing rates is a means by which oxygen intake and metabolic rates can be estimated to determine food requirements and energy expenditure of killer whales (Orcinus orca) and other cetaceans. This relatively simple measure also allows the energetic consequences of environmental stressors to cetaceans to be understood but requires knowing respiration rates while they are engaged in different behaviours such as resting, travelling and foraging. We calculated respiration rates for different behavioural states of southern and northern resident killer whales using video from UAV drones and concurrent biologging data from animal-borne tags. Behavioural states of dive tracks were predicted using hierarchical hidden Markov models (HHMM) parameterized with time-depth data and with labeled tracks of drone-identified behavioural states (from drone footage that overlapped with the time-depth data). Dive tracks were sequences of dives and surface intervals lasting ≥ 10 minutes cumulative duration. We calculated respiration rates and estimated oxygen consumption rates for the predicted behavioural states of the tracks. We found that juvenile killer whales breathed at a higher rate when travelling (1.6 breaths min-1) compared to resting (1.2) and foraging (1.5)—and that adult males breathed at a higher rate when travelling (1.8) compared to both foraging (1.7) and resting (1.3). The juveniles in our study were estimated to consume 2.5–18.3 L O2 min-1 compared with 14.3–59.8 L O2 min-1 for adult males across all behaviours based on estimates of mass-specific tidal volume and oxygen extraction. Our findings confirm that killer whales take single breaths between dives and indicate that energy expenditure derived from respirations requires using sex, age, and behavioural-specific respiration rates. These findings can be applied to bioenergetics models on a behavioural-specific basis, and contribute towards obtaining better predictions of dive behaviours, energy expenditure and the food requirements of apex predators. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
42. Assessment of Phthalate Esters and Physiological Biomarkers in Bottlenose Dolphins (Tursiops truncatus) and Killer Whales (Orcinus orca).
- Author
-
Lemos, Leila S., Di Perna, Amanda C., Steinman, Karen J., Robeck, Todd R., and Quinete, Natalia S.
- Subjects
- *
KILLER whale , *BOTTLENOSE dolphin , *POLLUTANTS , *PHTHALATE esters , *PHYSIOLOGY , *TOP predators - Abstract
Simple Summary: Delphinids are top predators and display long lifespans, making them susceptible to accumulating harmful environmental contaminants within their tissues, which may lead to potential adverse effects on their physiology and overall health. This study aimed to investigate exposure to phthalates in aquarium-based bottlenose dolphins and killer whales and explore potential correlations with individual physiological responses while accounting for sex, age, and reproductive stage. We found that all individuals were exposed to phthalates, including newborn dolphins. Phthalates were also correlated with aldosterone concentrations in killer whales, suggesting that this class of contaminants may exert disruptive effects on the endocrine system and metabolism of dolphins. This study could help us better understand the physiological mechanisms and effects of phthalate exposure in delphinids, which could lead to stricter contaminant discharge regulations, improving both human and aquatic/marine health. There is growing concern about the potential adverse health effects of phthalates (PAEs) on human health and the environment due to their extensive use as plasticizers and additives in commercial and consumer products. In this study, we assessed PAE concentrations in serum samples from aquarium-based delphinids (Tursiops truncatus, n = 36; Orcinus orca, n = 42) from California, Florida, and Texas, USA. To better understand the physiological effects of phthalates on delphinids, we also explored potential correlations between phthalates and the biomarkers aldosterone, cortisol, corticosterone, hydrogen peroxide, and malondialdehyde while accounting for sex, age, and reproductive stage. All PAEs were detected in at least one of the individuals. ΣPAE ranges were 5.995–2743 ng·mL−1 in bottlenose dolphins and 5.372–88,675 ng·mL−1 in killer whales. Both species displayed higher mean concentrations of DEP and DEHP. PAEs were detected in newborn delphinids, indicating transference via placenta and/or lactation. Linear mixed model results indicated significant correlations between aldosterone, month, location, status, and ΣPAEs in killer whales, suggesting that aldosterone concentrations are likely affected by the cumulative effects of these variables. This study expands on the knowledge of delphinid physiological responses to PAEs and may influence management and conservation decisions on contamination discharge regulations near these species. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
43. Behavioural heterogeneity across killer whale social units in their response to feeding opportunities from fisheries.
- Author
-
Auguin, Erwan, Guinet, Christophe, Mourier, Johann, Clua, Eric, Gasco, Nicolas, and Tixier, Paul
- Subjects
- *
SOCIETAL reaction , *PREDATORY aquatic animals , *BYCATCHES , *LIFE history theory , *FISHERIES , *KILLER whale , *MARINE fishes - Abstract
Intra‐population heterogeneity in the behavioural response of predators to changes in prey availability caused by human activities can have major evolutionary implications. Among these activities, fisheries, while extracting resources, also provide new feeding opportunities for marine top predators. However, heterogeneity in the extent to which individuals have responded to these opportunities within populations is poorly understood. Here, we used 18 years of photo‐identification data paired with statistical models to assess variation in the way killer whale social units within a subantarctic population (Crozet Islands) interact with fisheries to feed on fish caught on fishing gear (i.e., depredation behaviour). Our results indicate large heterogeneity in both the spatial and temporal extents of depredation across social units. While some frequently depredated on fishery catches over large areas, others sporadically did so and in small areas consistently over the years. These findings suggest that killer whale social units are exposed to varying levels of impacts of depredation, both negative (potential retaliation from fishers) and positive (food provisioning), on their life history traits, and may explain the contrasted demographic patterns observed within the declining population at Crozet but also potentially within the many other killer whale populations documented depredating on fisheries catches worldwide. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
- Full Text
- View/download PDF
44. 71th ORCA Congress.
- Subjects
- *
KILLER whale - Published
- 2024
- Full Text
- View/download PDF
45. Double Vision.
- Author
-
Dickson, Jamie
- Subjects
DIPLOPIA ,HANDICRAFT equipment ,KILLER whale ,GUITAR playing ,PRICES - Abstract
The article in "Guitarist" compares Gibson reissues of the iconic '59 'Burst Les Paul with boutique versions by Nik Huber. The author and former editor visited World Guitars to test various models, noting the differences in sound and craftsmanship. While the high-end Gibson reissues are faithful to the originals, the boutique Huber guitars offer a more contemporary and refined take on the classic sound. The article emphasizes the distinct character of each brand's guitars and suggests that personal preference plays a significant role in choosing between them. [Extracted from the article] more...
- Published
- 2025
46. Spatial and seasonal foraging patterns drive diet differences among north Pacific resident killer whale populations
- Author
-
Amy M. Van Cise, M. Bradley Hanson, Candice Emmons, Dan Olsen, Craig O. Matkin, Abigail H. Wells, and Kim M. Parsons
- Subjects
diet ,foraging ,killer whale ,metabarcoding ,faecal ,top marine predator ,Science - Abstract
Highly social top marine predators, including many cetaceans, exhibit culturally learned ecological behaviours such as diet preference and foraging strategy that can affect their resilience to competition or anthropogenic impacts. When these species are also endangered, conservation efforts require management strategies based on a comprehensive understanding of the variability in these behaviours. In the northeast Pacific Ocean, three partially sympatric populations of resident killer whales occupy coastal ecosystems from California to Alaska. One population (southern resident killer whales) is endangered, while another (southern Alaska resident killer whales) has exhibited positive abundance trends for the last several decades. Using 185 faecal samples collected from both populations between 2011 and 2021, we compare variability in diet preference to provide insight into differences in foraging patterns that may be linked with the relative success and decline of these populations. We find broad similarities in the diet of the two populations, with differences arising from spatiotemporal and social variability in resource use patterns, especially in the timing of shifts between target prey species. The results described here highlight the importance of comprehensive longitudinal monitoring of foraging ecology to inform management strategies for endangered, highly social top marine predators. more...
- Published
- 2024
- Full Text
- View/download PDF
47. Sense of an ending.
- Author
-
Monsó, Susana
- Subjects
- *
ANIMAL mortality , *KILLER whale , *ANIMAL weaning , *DEAD , *CALVES - Abstract
The article discusses the growing evidence of animals grieving the loss of loved ones, citing examples like the orca Tahlequah and young gorilla Segasira. It highlights the importance of not imposing human biases on nonhuman mourning behaviors, using the example of dogs potentially eating their deceased owners as a form of grief. The author calls for a shift away from anthropocentric perspectives in studying animal grief and urges researchers to explore diverse ways in which animals may understand and cope with mortality. [Extracted from the article] more...
- Published
- 2024
- Full Text
- View/download PDF
48. Pilot study: decoding the skin microbiome of bowhead (Balaena mysticetus) and killer whales (Orcinus orca) in Nunavut, Canada
- Author
-
Carlos A. Dominguez-Sanchez, Steven H. Ferguson, Tera Edkins, Brent G. Young, and Joshua Kringorn
- Subjects
microbiome ,bowhead whale ,killer whale ,strandings ,health ,Environmental sciences ,GE1-350 ,Environmental engineering ,TA170-171 - Abstract
Given the increasing challenges that Arctic cetaceans face, it is critical to investigate novel methods for assessing their health. Skin microbiomes have emerged as a promising method of detecting health issues that can help guide conservation efforts for free-ranging cetaceans. This study characterized the skin microbiome of 17 bowhead (BW) and 2 killer whales (KW). Fifty-six amplicon sequence variants were identified exclusively from cetacean samples, 20 belonged to BW, 13 to KW, and 23 to BW and KW. We identified bacteria from the genera Tenacibaculum and Psychrobacter, which have been previously described as bacteria that play a role in the health of cetaceans. In addition, in the healthy bowhead whale (H-BW) samples, we identified Clostridium sensu stricto 1 and 7, Carnobacterium spp., and Yersinia spp. which are of concern because these bacteria are opportunistic pathogens. Stranded BW had a less diverse microbiome than H-BW and had pathogens, including Aeromonas species and Streptococcus agalactia. Opportunistic pathogens of the genera Moritella (previously Vibrio spp.), Shewanella, Psychrilyobacter, and Legionella were discovered in KW. Due to their predator–prey relationships, the findings of this pilot study support the importance of keeping a close eye on the bowhead and killer whale populations in the Arctic. more...
- Published
- 2024
- Full Text
- View/download PDF
49. THE MAD SCIENTIST AND THE KILLER WHALES.
- Author
-
WEBER, TOMAS
- Subjects
- *
KILLER whale , *INFLATABLE boats , *CAPTIVE wild animals , *LOCATION data , *DIETARY patterns , *BEREAVEMENT - Abstract
Since 2020, there have been reports of orcas attacking boats off the coast of Spain and Portugal. These attacks have caused damage to boats, but no human fatalities. The orcas responsible are part of a group that researchers know little about. Some sailors have used firecrackers or loud music to deter the orcas, while others are concerned about violence towards the animals. Renaud de Stephanis, an orca expert, is studying the attacks and believes the behavior is play, not revenge. Other experts agree that revenge is unlikely and that orcas have complex emotions and social structures. Further research is needed to understand this behavior. [Extracted from the article] more...
- Published
- 2024
50. THE DISCOVERY ISLANDS.
- Author
-
Vipond, Anne and Kelly, William
- Subjects
ISLANDS ,TIDAL currents ,KILLER whale - Abstract
This article provides a firsthand account of the author's exploration of the Discovery Islands in British Columbia, Canada. The author discusses the challenges of navigating tidal rapids and highlights the tranquility and lack of boat traffic in the Octopus Islands and Waiatt Bay. They emphasize the use of guidebooks and current tables for planning their journey. The text also provides information on anchorages in British Columbia, including Kanish Bay, Small Inlet, and Gowlland Harbour, detailing their locations, anchoring options, and recreational activities. The presence of commercial traffic, cruise ships, killer whales, and fog is also mentioned. Overall, the anchorages are described as peaceful and scenic, making them potential destinations for boating or outdoor activities. [Extracted from the article] more...
- Published
- 2024
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.