Data from: Subarctic singers: Humpback whale (Megaptera novaeangliae) song structure and progression from an Icelandic feeding ground during winter

Humpback whale songs associated with breeding behaviors are increasingly reported outside of traditional low latitude breeding grounds. Songs from a subarctic feeding ground during the winter were quantitatively characterized to investigate the structure and temporal changes of the songs at such an atypical location. Recordings were collected from 26. January to 12. March, 2011, using bottom mounted recorders. Humpback songs were detected on 91% of the recording days with peak singing activities during 9.–26. February. The majority of the recordings included multiple chorusing singers. The songs were characterized by a) common static themes which transitioned consistently to predictable themes, b) shifting themes which occurred less predictably and c) rare themes. A set median sequence was found for four different periods (sets) of recordings (approximately 1 week each). The set medians were highly similar and formed a single cluster indicating that the sequences of themes sung in this area belonged to a single cluster of songs despite of the variation caused by the shifting themes. These subarctic winter songs could, thus, represent a characteristic song type for this area which is comparable to extensively studied songs from traditional low latitude breeding grounds. An increase in the number of themes per sequence was observed throughout the recording period including minor changes in the application of themes in the songs; indicating a gradual song progression. The results confirm that continual singing of sophisticated songs occur during the breeding season in the subarctic. In addition to being a well-established summer feeding ground the study area appears to be an important overwintering site for humpback whales delaying or canceling their migration where males engage in active sexual displays, i.e. singing. Importantly, such singing activity on a shared feeding ground likely aids the cultural transmission of songs in the North Atlantic

Call type repertoire of killer whales (Orcinus orca) in Iceland and its variation across regions

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 1985–2016. 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

Call type repertoire of killer whales (<i>Orcinus orca</i>) in Iceland and its variation across regions

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

Elevated symptoms of depression and anxiety among family members and friends of critically ill COVID-19 patients – an observational study of five cohorts across four countries

Background: Little is known regarding the mental health impact of having a significant person (family member and/or close friend) with COVID-19 of different severity.Methods: The study included five prospective cohorts from four countries (Iceland, Norway, Sweden, and the UK) with self-reported data on COVID-19 and symptoms of depression and anxiety during March 2020–March 2022. We calculated prevalence ratios (PR) of depression and anxiety in relation to having a significant person with COVID-19 and performed a longitudinal analysis in the Swedish cohort to describe temporal patterns.Findings: 162,237 and 168,783 individuals were included in the analysis of depression and anxiety, respectively, of whom 24,718 and 27,003 reported a significant person with COVID-19. Overall, the PR was 1.07 (95% CI: 1.05–1.10) for depression and 1.08 (95% CI: 1.03–1.13) for anxiety in relation to having a significant person with COVID-19. The respective PRs for depression and anxiety were 1.15 (95% CI: 1.08–1.23) and 1.24 (95% CI: 1.14–1.34) if the patient was hospitalized, 1.42 (95% CI: 1.27–1.57) and 1.45 (95% CI: 1.31–1.60) if the patient was ICU-admitted, and 1.34 (95% CI: 1.22–1.46) and 1.36 (95% CI: 1.22–1.51) if the patient died. Individuals with a significant person with hospitalized, ICU-admitted, or fatal COVID-19 showed elevated prevalence of depression and anxiety during the entire year after the COVID-19 diagnosis.Interpretation: Family members and close friends of critically ill COVID-19 patients show persistently elevated prevalence of depressive and anxiety symptoms

Population identity of North Atlantic humpback whales:An ocean-wide analysis of genetic population structure

North Atlantic (NA) humpback whales (Megaptera novaeangliae) undertake seasonal migrations between high latitude feeding areas (ranging from the US coast to the Barents Sea) and low latitude winter breeding grounds in the Caribbean and the eastern NA (e.g., the Cabo Verde Archipelago). We assessed the genetic structure in the NA analyzing genetic data from ~3,000 humpback whales sampled in 14 different locations across the NA as well as off Gabon, a South Atlantic breeding ground. Each individual was sexed, genotyped at 19 microsatellite loci and the mitochondrial control region (mtCR) was sequenced. Bayesian cluster analyses and fixation indices detected two breeding populations within the NA and an additional population off Gabon. A high degree of genetic divergence was detected among the mtCR sequences between the western and eastern NA high latitude summer feeding areas indicative of long-term maternal site-fidelity to these two regions. Kinship-based analyses revealed the high latitude feeding areas in the NA as the summer destination for individuals wintering in the Cabo Verde Archipelago. There were clear signs of gene flow and introgression into the eastern NA breeding population from the Caribbean breeding population; evident by immigrants from the Caribbean breeding population and admixed individuals. The individuals on the eastern NA breeding grounds with a 100% eastern NA ancestry, all shared the same, unique mtCR haplotype; i.e., all belonging to the same single matrilineal lineage. This maternal lineage is endemic to the eastern NA, highlighting the rarity, and thus endangered, of the eastern NA breeding population. Furthermore, the study uncovered evidence of migration from the Southern to the Northern Hemisphere. Overall, our results provide a comprehensive overview of the population structure of NA humpback whales throughout the ocean basin

Population identity of North Atlantic humpback whales:An ocean-wide analysis of genetic population structure

North Atlantic (NA) humpback whales (Megaptera novaeangliae) undertake seasonal migrations between high latitude feeding areas (ranging from the US coast to the Barents Sea) and low latitude winter breeding grounds in the Caribbean and the eastern NA (e.g., the Cabo Verde Archipelago). We assessed the genetic structure in the NA analyzing genetic data from ~3,000 humpback whales sampled in 14 different locations across the NA as well as off Gabon, a South Atlantic breeding ground. Each individual was sexed, genotyped at 19 microsatellite loci and the mitochondrial control region (mtCR) was sequenced. Bayesian cluster analyses and fixation indices detected two breeding populations within the NA and an additional population off Gabon. A high degree of genetic divergence was detected among the mtCR sequences between the western and eastern NA high latitude summer feeding areas indicative of long-term maternal site-fidelity to these two regions. Kinship-based analyses revealed the high latitude feeding areas in the NA as the summer destination for individuals wintering in the Cabo Verde Archipelago. There were clear signs of gene flow and introgression into the eastern NA breeding population from the Caribbean breeding population; evident by immigrants from the Caribbean breeding population and admixed individuals. The individuals on the eastern NA breeding grounds with a 100% eastern NA ancestry, all shared the same, unique mtCR haplotype; i.e., all belonging to the same single matrilineal lineage. This maternal lineage is endemic to the eastern NA, highlighting the rarity, and thus endangered, of the eastern NA breeding population. Furthermore, the study uncovered evidence of migration from the Southern to the Northern Hemisphere. Overall, our results provide a comprehensive overview of the population structure of NA humpback whales throughout the ocean basin