A winter sighting of killer whales (Orcinus orca ) in Antarctic sea ice

 A group of killer whales was sighted in open leads well inside Antarctic sea ice during August 1995. This was the first winter sighting of killer whales in Antarctic waters since 1955, and contradicts the view that all killer whales migrate north prior to the winter. A small calf was observed, providing the first evidence of a cetacean species breeding in Antarctic waters. Several potential prey species were also present. The sighting highlights the importance of lead and polynya systems to marine mammals, which probably use them to disperse within the winter sea-ice zone. Received: 23 April 1996 / Accepted: 25 August 1996     

Social structure of killer whales (Orcinus orca) in a variable low-latitude environment,the Galápagos Archipelago

Killer whales (Orcinus orca) have strong social matrilineal bonds and form groups and long-lasting associations, but little is known about their population or social structure in an equatorial setting such as the waters around the Galápagos Islands. Using 91 encounters and identification photographs from 1991 to 2017, we identified 64 killer whales of which 18 individuals were locals with high resighting rates. Group size was small, ranging from 1 to 15 animals, with 69% of the groups containing four or fewer animals. Using social network analysis (SOCPROG 2.7) whales grouped into three distinct units and one loose association with frequent exchange between different groups. One male–male unit showed a strong association (association strength = 0.55). Overall, associations lasted over at least 3 years. Our data give first evidence of a loose social organization of Galápagos killer whales, similar to fission-fusion societies.     

Harassment and killing of porpoises (“phocoenacide”) by fish-eating Southern Resident killer whales (Orcinus orca)

Endangered Southern Resident killer whales (Orcinus orca) are fish-eaters that preferentially prey on adult Chinook salmon (Oncorhynchus tshawytscha). Despite being salmon specialists, individuals from all three killer whale pods (J, K, L) have been observed harassing and killing porpoises (family Phocoenidae) without consuming them. Retrospectively, we identified and analyzed 78 episodes of Southern Resident killer whales harassing porpoises between 1962 and 2020, of which 28 resulted in the porpoise's death (“phocoenacide”). Fifty-six episodes involved harbor porpoise (Phocoena phocoena), 13 involved Dall's porpoise (Phocoenoides dalli), and the porpoise species was unreported for nine episodes. Southern Resident killer whales often targeted young porpoises that were similar in size to adult Chinook salmon. Both sexes participated in porpoise harassment. Juveniles engaged in the behavior the most; however, their rates of engagement were not found to differ significantly from most other age classes. The behavior was passed through generations and social groupings, as it was first observed in L pod and spread to the other two pods. Killer whales are highly complex animals known to exhibit social learning and cultural transmission of learned behaviors, but the reason(s) for this behavior is unknown. Hypotheses include the social and developmental benefits of play, hunting practice, or displaced epimeletic behavior.     

Killer Whale (Orcinus orca) Deaths in Prince William Sound,Alaska, 1985–1990

During 1985–1990, two groups of killer whales in Prince William Sound, Alaska, experienced unusually high rates of mortality, while seven others did not. Those affected were AB pod, part of the southern Alaska population of resident (fish-eating) killer whales, and the AT1 transient (marine mammal–eating) group, a very small, reproductively isolated population that last reproduced in 1984. In 1985–1986, several AB pod members were shot by fishermen defending their catch from depredation, which explains some of the deaths. Understanding the other deaths is complicated by the Exxon Valdez oil spill (March 1989) and uncertainties about the causes and times of the deaths. For AB pod, possible factors involved in the post-spill mortalities are delayed effects of bullet wounds, continued shooting, oil exposure, and consequences of being orphaned. For the AT1 group, possible factors are oil exposure, small population size, old age, and high-contaminant burdens. An analysis of possible effects of inhalation of volatile organic compounds, contact with the oil slick, and ingestion of oil with water or prey did not reveal route(s) of exposure that could explain the mortalities. The cause(s) of the killer whale deaths recorded following the oil spill remain uncertain.     

Estimation of a Killer Whale (Orcinus orca) Population’s Diet Using Sequencing Analysis of DNA from Feces

Estimating diet composition is important for understanding interactions between predators and prey and thus illuminating ecosystem function. The diet of many species, however, is difficult to observe directly. Genetic analysis of fecal material collected in the field is therefore a useful tool for gaining insight into wild animal diets. In this study, we used high-throughput DNA sequencing to quantitatively estimate the diet composition of an endangered population of wild killer whales (Orcinus orca) in their summer range in the Salish Sea. We combined 175 fecal samples collected between May and September from five years between 2006 and 2011 into 13 sample groups. Two known DNA composition control groups were also created. Each group was sequenced at a ~330bp segment of the 16s gene in the mitochondrial genome using an Illumina MiSeq sequencing system. After several quality controls steps, 4,987,107 individual sequences were aligned to a custom sequence database containing 19 potential fish prey species and the most likely species of each fecal-derived sequence was determined. Based on these alignments, salmonids made up >98.6% of the total sequences and thus of the inferred diet. Of the six salmonid species, Chinook salmon made up 79.5% of the sequences, followed by coho salmon (15%). Over all years, a clear pattern emerged with Chinook salmon dominating the estimated diet early in the summer, and coho salmon contributing an average of >40% of the diet in late summer. Sockeye salmon appeared to be occasionally important, at >18% in some sample groups. Non-salmonids were rarely observed. Our results are consistent with earlier results based on surface prey remains, and confirm the importance of Chinook salmon in this population’s summer diet.     

Echolocation in Blainville’s beaked whales (Mesoplodon densirostris)

Here we use sound and movement recording tags to study how deep-diving Blainville’s beaked whales (Mesoplodon densirostris) use echolocation to forage in their natural mesopelagic habitat. These whales ensonify thousands of organisms per dive but select only about 25 prey for capture. They negotiate their cluttered environment by radiating sound in a narrow 20° field of view which they sample with 1.5–3 clicks per metre travelled requiring only some 60 clicks to locate, select and approach each prey. Sampling rates do not appear to be defined by the range to individual targets, but rather by the movement of the predator. Whales sample faster when they encounter patches of prey allowing them to search new water volumes while turning rapidly to stay within a patch. This implies that the Griffin search–approach–capture model of biosonar foraging must be expanded to account for sampling behaviours adapted to the overall prey distribution. Beaked whales can classify prey at more than 15 m range adopting stereotyped motor patterns when approaching some prey. This long detection range relative to swimming speed facilitates a deliberate mode of sensory-motor operation in which prey and capture tactics can be selected to optimize energy returns during long breath-hold dives.     

C. S. Sargent’s crataegus (Rosaceae) types from western Pennsylvania

A large amount of unmounted material ofCrataegus (Rosaceae) at Carnegie Museum (CM) was studied and found to include types of species described by C. S. Sargent from western Pennsylvania. These are of interest because Sargent'sCrataegus types were previously thought to be only at the Arnold Arboretum (A). Sargent's method of choosing types (designating a living “type tree” and citing several specimens collected from it) is discussed and clarified.Crataegus types at A were compared with the material at CM. An annotated list of the western Pennsylvania types in both herbaria is presented.     

Call Characteristic Network Reveal Geographical Patterns of Call Similarity:Applying Network Analysis to Frog’s Call Research

Individual’s phenotypic traits are the results of adaptation to ecological conditions.Therefore,different selection pressures caused by heterogeneous environments may result in phenotypic difference,especially for individuals in different geographical populations.Here,we illustrated for the first time to use social network analysis(SNA)for examining whether geographical proximity predicts the similarity patterns in call characteristics among populations of an anuran species.We recorded calls from 150 male dorsal-striped opposite-fingered treefrogs(Chiromantis doriae)at 11 populations in Hainan Province and one population in Guangdong Province in China's Mainland,and we measured eight acoustic variables for each male.Mantel test didn’t show a correlation between geographical proximity and the similarity in call characteristics among populations.In addition,we failed to find correlations between a population’s eigenvector centrality and the distance to its nearest neighbor,nor between the coefficient of variation of similarity in call characteristics of a population and the average distance to all other populations.Nevertheless,three acoustic clusters were identified by the Girvan-Newman algorithm,and clustering was partially associated with geography.Furthermore,the most central populations were included in the same cluster,but the top betweenness populations were located within different clusters,suggesting that centrality populations are not necessary bridging between clusters.These results demonstrate the potential usefulness of the SNA toolbox and indicate that SNA helps to uncover the patterns that often overlooked in other analytical methods.By using SNA in frog’s call studies,researchers could further uncover the potential relationship in call characteristics between geographical populations,further reveal the effects of ecological factors on call characteristics,and probably enhance our understanding of the adaptive evolution of acoustic signals.     

Evaluation of genetic diversity and population structure of Macqueen’s Bustard Chlamydotis macqueenii in Iran

Capsule: There is low genetic diversity in the Macqueen’s Bustard Chlamydotis macqueenii in Iran.

Aims: To investigate the genetic diversity and population structure of Macqueen’s Bustard in Iran, using two mitochondrial DNA loci.

Methods: Molecular diversity of the mitochondrial cytochrome oxidase c subunit I (COI) gene and part of the mitochondrial control region D-loop (in total 1183 base pairs) were analysed from 26 individual Macqueen’s Bustards from three regions of Iran.

Results: There was little variation in nucleotides and haplotypes in the populations for genes of both CR and COI. The population had free breeding and gene flow between the three study regions in Iran: Petregan, Ferdows and Yazd.

Conclusion: The use of molecular and genetic studies is essential to strengthen the protection of genetic diversity of the Macqueen’s Bustard.     

Genomic population structure of freshwater‐resident and anadromous ide (Leuciscus idus) in north‐western Europe

Climate change experts largely agree that future climate change and associated rises in oceanic water levels over the upcoming decades, will affect marine salinity levels. The subsequent effects on fish communities in estuarine ecosystems however, are less clear. One species that is likely to become increasingly affected by changes in salinity is the ide (Leuciscus idus). The ide is a stenohaline freshwater fish that primarily inhabits rivers, with frequent anadromous behavior when sea salinity does not exceed 15%. Unlike most other anadromous Baltic Sea fish species, the ide has yet to be subjected to large‐scale stocking programs, and thus provides an excellent opportunity for studying the natural population structure across the current salinity gradient in the Danish Belts. To explore this, we used Genotyping‐by‐Sequencing to determine genomic population structure of both freshwater resident and anadromous ide populations in the western Baltic Sea region, and relate the results to the current salinity gradient and the demographic history of ide in the region. The sample sites separate into four clusters, with all anadromous populations in one cluster and the freshwater resident populations in the remaining three. Results demonstrate high level of differentiation between sites hosting freshwater resident populations, but little differentiation among anadromous populations. Thus ide exhibit the genomic population structure of both a typical freshwater species, and a typical anadromous species. In addition to providing a first insight into the population structure of north‐western European ide, our data also (1) provide indications of a single illegal introduction by man; (2) suggest limited genetic effects of heavy pollution in the past; and (3) indicate possible historical anadromous behavior in a now isolated freshwater population.     

Seasonal variation in genetic population structure of sábalo (Prochilodus lineatus) in the Lower Uruguay River

Prochilodus lineatus is a highly migratory fish species that sustains the most important commercial fishery of Paraná-Paraguay basin. Migratory patterns are poorly known and only few population genetic studies are available for this species in the Upper Paraná. To assess genetic population structure, we genotyped a sample of 93 individuals from the Lower Uruguay River close to Gualeguaychú city (Entre Ríos, Argentina) at three different times, July 2008 (Winter), September 2008 (Spring) and May 2009 (Fall). All individuals were genotyped for 12 microsatellite loci previously found to be informative to assess populations of P. lineatus. Our results show seasonal variation of the genetic sub-structuring at this locality that may be related to the presence of different migratory stocks throughout the year. The Fall sample includes an additional genetic cluster of individuals not detected in Winter and Spring, suggesting that this species should be considered a mixed stock fishery.     

Genetic diversity and population structure of North America’s rarest heron, the reddish egret (Egretta rufescens)

The global distribution of the reddish egret is characterized by disjunct colonies occurring from the Pacific side of Northwest Mexico to the Caribbean. We examined distantly isolated colonies of reddish egret to determine global population genetic structure. We used seven polymorphic microsatellites to accomplish five goals: (1) to assess range wide population differentiation among reddish egret (Egretta rufescens) populations, (2) identify extent of gene flow, (3) determine any historical occurrence of bottlenecks, (4) assess genetic differentiation between color morphs, (5) clarify subspecies status of E. r. dickeyi, a completely dark morph population located in and around the Baja California peninsula, Mexico. Genetic differentiation was dramatic (global Fst = 0.161) throughout the reddish egrets range extending from Baja California, Mexico to Great Inagua, Bahamas. Differentiation occurred among three distinct regions (Fst = 0.238) but not among colonies/islands within regions suggesting regional philopatry. Genetic diversity (alleles per locus, and heterozygosity) in Baja California Sur, Mexico and Great Inagua, Bahamas populations is lower than in the Texas/Mexico population due to minimal dispersal between regions and smaller population sizes. Dark and white color morphs when present within the same region showed no differentiation. Patterns of recent population bottlenecks are not evident in each of the three regional populations. With evidence of limited gene flow in addition to low genetic diversity and prospects of habitat loss we recommend that reddish egrets be managed as three distinct or evolutionary significant units.     

Genetic analysis of interspecific hybridisation in the world’s only Forbes’ parakeet (Cyanoramphus forbesi) natural population

Genetic introgression from Chatham Island Red-crowned parakeet (Cyanoramphus novaezelandiae chathamensis) is a long-standing problem in the conservation of the rare Forbes’ parakeet (C. forbesi) on Mangere Island, New Zealand. Microsatellite genotypes, mitochondrial DNA sequences, and morphological markers have been applied to study the situation. An extensive history of hybridisation was detected in the single remaining Forbes’ parakeet population, where no less than 81% of all birds screened are considered hybrids. Genetic markers showed that a large proportion of birds identified as Forbes’ parakeets by crown plumage are cryptic hybrids. Only a small proportion of birds with Forbes’ parakeet morphotype were found to be genetically distinct from Chatham Island Red-crowned parakeets using microsatellite and mitochondrial DNA assignment tests, but these still represent an Evolutionarily Significant Unit (ESU) for conservation.     

Causes of mortality in a Geoffroy’s cat population—a long-term survey using diverse recording methods

We present quantitative data on the impact of different causes of mortality in a Geoffroy’s cat (Leopardus geoffroyi) population inhabiting a protected area and adjacent cattle ranches in central Argentina. Between December 2000 and January 2009, we used three methods to collect data on causes of mortality in both the park and the ranches: (1) information obtained from 35 radio-collared Geoffroy’s cats monitored from 1 to 19 months; (2) a systematic survey of the areas to find non-collared dead animals; and (3) interviews of qualified informants. Deaths of radio-collared individuals in the park were due to predation by puma (Puma concolor) or starvation, whereas deaths in the ranches were attributed to starvation and predation by domestic dogs. The death of eight emigrant cats was attributed mainly to poaching. Cause of death of 39 non-collared Geoffroy’s cats was determined; deaths in the ranches were mainly due to predation by domestic dogs and poaching, whereas deaths in the park were attributed to predation by puma, poaching, and vehicle collision. Grouping all sources of information, human-related mortality accounted for most (62%) of Geoffroy’s cat deaths recorded during this study, with poaching and predation by dogs being the main causes of mortality. This study in Geoffroy’s cats is the first long-term survey of causes of mortality for a population of a small felid species in South America.     

Prevalence and predictors of dysmenorrhea among a population of adolescent’s schoolgirls (Morocco)

Dysmenorrhea is the most common gynaecological problem among young females. In Arabic countries, few studies on gynaecological problems of adolescent’s girls were published. Objective: the aim of the study was to determine the prevalence of dysmenorrhea and associated factors among adolescents in public schools at Marrakesh. Methods: we conducted a cross-sectional study; our data was collected via a questionnaire and the statistical analysis was done using SPSS version 21. Our random sample counted 364 post-menarcheal girls aged between 12 and 20 years who participated voluntarily in our study. Results: the mean age at menarche was 12.89 ± 1.34 years; the prevalence of dysmenorrhea was 78% and 58.1% of them suffering from severe dysmenorrhea that increased clearly with the chronological age. Dysmenorrhea was cause for missing school among 13% of girls and the most common symptoms associated with it were backache, fatigue, irritability and anxiety. The gynecological age was found to be the only predictive factor of dysmenorrhea among schoolgirls. Conclusion: reproductive health education should be improved enough by including them in the school curriculum to prepare girls for menstruation and inform them about problems related to this phenomenon, especially dysmenorrhea.