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The Eurasian Otter Lutra lutra is an elusive, solitary animal that has one of the widest distributions of all palearctic mammals. Once widely distributed in Asia, the Eurasian Otter population is now vulnerable to urbanization, pollution, poaching, and dam construction. Eurasian Otter distribution in the Indian Himalayan rivers is little explored, and information from this high-altitude riverine ecosystem is sparse. This publication reports a rare photographic record of the Eurasian Otter which confirms its presence in the high-altitude temperate forest of the Upper Bhagirathi Basin, western Himalayan region. The otter was recorded during investigations of terrestrial and aquatic fauna in the Bhagirathi Basin (7,586 km2, 500–5,000 m) of Uttarakhand State, India from October 2015 to May 2019. Among aquatic fauna, Brown Trout were found to be abundant in high altitude river stretches, with a catch per unit effort of 1.02 kg h–1. Additionally, 26 families of freshwater macroinvertebrates underscored a rich diet available for the Brown Trout, which in turn is a potential food source for the otters. The riverine ecosystem is undergoing dramatic changes because of the increasing demand for hydropower plants in the Bhagirathi Basin. Although mitigation measures are currently in place for fish, the presence of otters further necessitates the need for targeted management for high-altitude Himalayan rivers. There is an imperative need for intensive otter surveys using methods such as camera traps in riparian habitats along the Bhagirathi River and its tributaries.

Monitoring the demographics and genetics of reintroduced populations is critical to evaluating reintroduction success, but species ecology and the landscapes that they inhabit often present challenges for accurate assessments. If suitable habitats are restricted to hierarchical dendritic networks, such as river systems, animal movements are typically constrained and may violate assumptions of methods commonly used to estimate demographic parameters. Using genetic detection data collected via fecal sampling at latrines, we demonstrate applicability of the spatial capture–recapture (SCR) network distance function for estimating the size and density of a recently reintroduced North American river otter (Lontra canadensis) population in the Upper Rio Grande River dendritic network in the southwestern United States, and we also evaluated the genetic outcomes of using a small founder group (n = 33 otters) for reintroduction. Estimated population density was 0.23–0.28 otter/km, or 1 otter/3.57–4.35 km, with weak evidence of density increasing with northerly latitude (β = 0.33). Estimated population size was 83–104 total otters in 359 km of riverine dendritic network, which corresponded to average annual exponential population growth of 1.12–1.15/year since reintroduction. Growth was ≥40% lower than most reintroduced river otter populations and strong evidence of a founder effect existed 8–10 years post‐reintroduction, including 13–21% genetic diversity loss, 84%–87% genetic effective population size decline, and rapid divergence from the source population (F ST accumulation = 0.06/generation). Consequently, genetic restoration via translocation of additional otters from other populations may be necessary to mitigate deleterious genetic effects in this small, isolated population. Combined with non‐invasive genetic sampling, the SCR network distance approach is likely widely applicable to demogenetic assessments of both reintroduced and established populations of multiple mustelid species that inhabit aquatic dendritic networks, many of which are regionally or globally imperiled and may warrant reintroduction or augmentation efforts., Monitoring the demographics and genetics of reintroduced populations is critical to evaluating reintroduction success, but species ecology and the landscapes that they inhabit often present challenges for accurate assessments. Using genetic detection data collected via fecal sampling at latrines, we demonstrate applicability of the spatial capture–recapture (SCR) network distance function for estimating the size and density of a recently reintroduced North American river otter (Lontra canadensis) population in the Upper Rio Grande River dendritic network in the southwestern United States, and we also evaluated the genetic outcomes of using a small founder group for reintroduction. Combined with noninvasive genetic sampling, the SCR network distance approach is likely widely applicable to demogenetic assessments of both reintroduced and established populations of multiple mustelid species that inhabit aquatic dendritic networks, many of which are regionally or globally imperiled and may warrant reintroduction or augmentation efforts.

Two complementary approaches were used to assess year-round variation in the diet of sea otters Enhydra lutris around Prince of Wales Island (POW) in southern Southeast Alaska, a region characterized by mixed-bottom habitat. We observed sea otters foraging to determine diet composition during the spring and summer. Then, we obtained sea otter vibrissae, which record temporal foraging patterns as they grow, from subsistence hunters to identify year-round changes in sea otter diets via stable isotope analysis of carbon (δ13C) and nitrogen (δ15N). We compared the stable isotopes from sea otter vibrissae and sea otter prey items that were collected during spring, summer, and winter. Overall, year-round sea otter diet estimates from stable isotope signatures and visual observations from spring and summer were dominated by clams in terms of biomass, with butter clams Saxidomus gigantea the most common clam species seen during visual observations. Our results indicate that these sea otters, when considered together at a regional level around POW, do not exhibit shifts in the main prey source by season or location. However, sea otter diets identified by stable isotopes had a strong individual-level variation. Behavioral variation among individual sea otters may be a primary driving factor in diet composition. This study provides quantitative diet composition data for modeling predictions of invertebrate population estimates that may aid in the future management of shellfisheries and subsistence hunting and the development of co-management strategies for this protected species.

On the River Ticino in northern Italy, a small number of captive Eurasian otters Lutra lutra, belonging to the European breeding programme for self-sustaining captive populations, were reintroduced in 1997, after the species had been declared locally extinct in the 1980s. We surveyed for otter signs in 2008, 2010, 2016–2017 and 2018, confirming the presence of what is probably a small population. To assess the abundance and viability of the population, we genotyped fresh spraints collected during the last two surveys, using 11 microsatellite markers, and modelled the population trend using Vortex. A minimum of six individuals were identified from 25 faecal samples. The analysis of mitochondrial DNA determined that the reintroduced otters share a transversion that is characteristic of the Asiatic subspecies Lutra lutra barang, confirming the contribution of the Asiatic subspecies to the genetic pool of the captive-bred founder population. Population size was consistent with the release of three pairs of otters and all models implied that the number of founders was too small to ensure the long-term survival of the population. Stochastic factors are therefore likely to threaten the success of this reintroduction.

Previous research in southeast Alaska on the effects of sea otters Enhydra lutris in seagrass Zostera marina communities identified many but not all of the trophic relationships that were predicted by a sea otter-mediated trophic cascade. To further resolve these trophic connections, we compared biomass, carbon (δ13C) and nitrogen (δ15N) stable isotope (SI), and fatty acid (FA) data from 16 taxa at 3 sites with high and 3 sites with low sea otter density (8.2 and 0.1 sea otters km-2, respectively). We found lower crab and clam biomass in the high sea otter region but did not detect a difference in biomass of other seagrass community taxa or the overall community isotopic niche space between sea otter regions. Only staghorn sculpin differed in δ13C between regions, and Fucus, sugar kelp, butter clams, dock shrimp, and shiner perch differed in δ15N. FA analysis indicated multivariate dissimilarity in 11 of the 15 conspecifics between sea otter regions. FA analysis found essential FAs, which consumers must obtain from their diet, including 20:5ω3 (EPA) and 22:6ω3 (DHA), were common in discriminating conspecifics between sea otter regions, suggesting differences in consumer diets. Further FA analysis indicated that many consumers rely on diverse diets, regardless of sea otter region, potentially buffering these consumers from sea otter-mediated changes to diet availability. While sea otters are major consumers in this system, further studies are needed to understand the mechanisms responsible for the differences in biomarkers between regions with and without sea otters.

Fishing with otters is an ancient fishing technique in Bangladesh, exists only in the south-western part of the country with smooth-coated Otter (Lutrogale perspicillata). The present study was carried out to portray this unique fishing technique and to investigate otter fishers` livelihood status in Narail District. Fishing with otters is carried out at night in the Chitra and the Nabaganga rivers, involving at least four people, a boat, a net, 2-3 adult tamed otters and 1-2 immature trainee otters. The socio-economic conditions and livelihood status of the otter fishers` were found as not-satisfactory level whereas about 75% of total 36 fishermen were termed as very poor and they don`t have their own boat and nets for fishing. All of the surveyed fishers belong to the Hindu religion and less access to education, pure drinking water, and a healthy sanitation system. Due to scanty income, and resultant low-living standard, 14 otter fishers were found changed their ancient profession. Therefore, direct interventions are essential to support improved and sustainable socio-economic condition of the otter fishing community. Res. Agric., Livest. Fish.8(2): 249-257, August 2021

Heirloom barley (Hordeum vulgare L.) varieties remain interesting to maltsters and brewers for their perceived unique flavor contributions to beer, despite not meeting contemporary agronomic and malting expectations. This study utilized crosses of the heirloom Maris Otter® and two contemporary genotypes to determine if “updated heirlooms” could be produced that would show improved agronomics and contemporary malt quality, while contributing uniquely to malt and beer sensory and chemical profiles. Using a recently established pipeline of malting; brewing; hot steep and beer sensory; and metabolomics to evaluate barley genotype contributions to malt and beer flavor, four experimental lines were compared to a control. The experimental lines were also assessed for their genomic contribution from their respective parents to further elucidate regions of the Maris Otter genome that may contribute to unique beer flavors. Results show improved agronomic outcomes relative to the heirloom parent and were comparable to the control. Malting quality met current recommendations. However, sensory properties attributable to the unique heirloom parent were not found. Further, chemical profiling did not explain the observed nuanced sensory differences, nor did it reveal unique metabolites not described by the sensory panels. Supplemental data for this article is available online at at http://doi:10.1080/03610470.2021.1952509.

Mites from the family Halarachnidae Oudemans 1906 are obligate endoparasites that colonize the respiratory tracts of free-living and captive marine mammals. Infestations can range from mild to severe and result in respiratory tract irritation or impairment. Nasopulmonary acariasis was determined to be a contributing cause of death among several southern sea otters Enhydra lutris nereis Merriam 1904 in a longitudinal study of otter mortality, and proximity to Pacific harbor seals Phoca vitulina richardii Gray 1864 was a significant risk factor for sea otter infestation. Beyond scattered opportunistic reports, each halarachnid mite species' affinity for particular hosts and the extent of mite transmission between host species is poorly understood. We investigated the identity and prevalence of nasopulmonary mites from Pacific harbor seals, California sea lions Zalophus californianus Lesson 1828, northern elephant seals Mirounga angustirostris Gill 1866, northern fur seals Callorhinus ursinus Linnaeus 1758, and Guadalupe fur seals Arctocephalus philippii townsendi Merriam 1897 to complement published nasopulmonary mite findings from sympatric southern sea otters during a comparable timeframe. Halarachnid mite infestation was common among California sea lions (74.1%), northern fur seals (73.3%), and northern elephant seals (46.6%), but was less common among harbor seals (18.7%) and Guadalupe fur seals (8.8%). Observed host-mite relationships suggest a distinct host specificity, with genus Orthohalarachne infesting otariids, and genus Halarachne infesting phocids and lutrinids along the California coast. Harbor seals and southern sea otters were the primary hosts of H. halichoeri, but one nothern elephant seal was infested with both H. miroungae and a single H. halichoeri. We also present the first high-resolution SEM images for H. miroungae and O. attenuata and possible evidence for a new host record for H. halichoeri., Graphical abstract Image 1, Highlights • Host-mite relationships suggest a distinct host specificity among halarachnid genera. • Halarachnid mite infestation is common among Pacific pinnipeds. • Harbor seals and southern sea otters were the primary hosts of H. halichoeri. • 16S sequences of mites from Halarachne and Orthohalarachne were generated. • Scanning electron micrographs of H. miroungae and O. attenuata were generated.

While it is well known that Eurasian otters principally feed on fishes and crustaceans, their detailed diet taxonomies are not fully understood. This is partly due to their nocturnal behavior and the limited resolving power of traditional morphological identification from scat. A suitable, reliable molecular method for diet studies is therefore needed.I performed a series of Sanger‐sequencing reactions, utilizing nine primer sets for Eurasian otter diet research. These are mainly based on the barcoding concept to determine the taxonomic composition of spraints. The primer sets target different types of animals, amplifying each separately. This procedure was used to detect the prey contents of 64 spraint samples collected from Kinmen Island. Through high‐resolution gel electrophoresis and sequencing, it was evident that PCR products could be successfully amplified by the different primer sets and from spraint samples comprising multiple prey species.Extracted DNA from all spraint samples was PCR‐amplified with 9 primer sets. In total, 16 prey types were identified across all 64 samples. Fourteen were identified at the species level.The aim of this study was to develop and apply a novel diet research method to Eurasian otters. Eight of the primers are universal primers designed for COI segments of different animal groups, and one primer set was designed specifically for tilapia groups. This method can be applied to study the diets of not only Kinmen Eurasian otter populations, but also other Eurasian otter populations and other small carnivorous animals., A Eurasian otter eating a tilapia in Tai Lake, Kinmen. The photograph was taken by Fu‐Sheng Huang in June 2020.

Mass mortality events (MMEs) can remove up to 90% of individuals in a population and are especially damaging to population viability of long-lived species with slow life histories. Our goal was to elucidate the cause(s) of a MME of 53 Blanding’s Turtles (Emydoidea blandingii (Holbrook, 1838)), a globally endangered species, in a protected area. We investigated disease, winter-kill, and depredation as potential causes of the mortality. The turtle carcasses lacked soft tissue to test for disease, so we examined tissue from co-occurring live Leopard Frogs (Lithobates pipiens (Schreber, 1782)) and found no evidence of ranavirus, indicating that the disease was not present at our study site. Water temperature and dissolved aquatic oxygen at known overwintering sites and sites which yielded carcasses did not differ, suggesting that winter-kill did not cause the MME. Carcass condition, comparisons with descriptions of turtle depredation events in the literature, and trail cameras paired with turtle decoys identified potential predators within the study site and suggested that mass depredation, enabled by low water levels and a concomitant reduction in aquatic habitat, was the most likely cause of mortality. Our study can inform conservation of the study population and the management of MMEs of long-lived species elsewhere.

La présente étude cherche à déterminer le rôle et la signification culturelle des otariidés et des mustélidés dans l’évolution historique et culturelle du détroit de Magellan, à la pointe sud de l’Amérique du Sud. La situation géographique de ce couloir interocéanique a permis dès le début du xvie siècle le passage des navigateurs européens qui nourrissaient des ambitions géopolitiques et commerciales, mais elle a également rendu possible l’échange, la transmission et la transformation de savoirs en matière de navigation. Notre recherche se concentre sur la chasse aux pinnipèdes et aux loutres selon une une large échelle chronologique prenant en compte des vestiges archéozoologiques découverts sur des sites d’occupation datant d’environ 7 500 ans cal BP, jusqu’à une époque récente (700 ans BP sans cal.). Ont également été prises en compte des données historiques sur l’activité des chasseurs occidentaux à la fin du xviiie siècle et au début du xixe siècle dans les eaux du détroit de Magellan, au moment où la surexploitation des otaries a pour conséquence une baisse de leur démographie et un impact sur les écosystèmes marins. L’étude archéozoologique montre que, en dépit du fait que ce type de chasse représente une importante ressource économique dès les premières occupations d’Indiens canoeros ou nomades marins, il existe des périodes culturelles au cours desquelles elle a joué un rôle moins prépondérant que celui de la chasse aux oiseaux marins ou de la pêche (ca. 3200 à 2300 BP). On peut donc en déduire que son importance pour la subsistance de ces groupes humains n’est pas constante, peut-être en raison de facteurs que nous ne connaissons pas aujourd’hui liés à des changements environnementaux ou culturels.Enfin, nous avons pu observer l’évolution du rôle joué par les pinnipèdes et les loutres dans le contexte socioculturel indigène, qui de ressources vitales, pour se nourrir, se loger et s’abriter, ces animaux sont devenus, au fil des xviiie et xixe siècles, une marchandise destinée aux échanges et au commerce interethniques. Cette évolution aura des répercussions majeures pour ces sociétés. This study seeks to determine the role and cultural significance of otariids and mustelids in the historical and cultural evolution of the Strait of Magellan, at the southern tip of South America. The geographical location of this inter-oceanic corridor not only allowed the passage of European navigators with geopolitical and commercial ambitions from the beginning of the 16th century, but also made possible the exchange, transmission and transformation of knowledge about the sea.Our research focuses on the hunting of pinnipeds and otters with a broad temporal approach, taking into account archaeozoological evidence from occupation sites dating from around 7,500 years ago to recent times. Historical data on the activity of foreign seal-skinners in the late 18th and early 19th centuries in the waters of the Strait of Magellan were also taken into account, at a time when the overexploitation of sea lions was having an impact on the demography of pinnipeds and, consequently, on marine ecosystems. The archaeological study shows that, despite the fact that this type of hunting was an important economic resource from the earliest occupations of canoeing or marine nomadic Indians, there are cultural periods in which it played a less prominent role than seabird hunting or fishing (ca. 3200 to 2300 BP). This suggests that its importance for the subsistence of these human groups is not constant, perhaps due to factors that we do not know today related to environmental changes and/or cultural phenomena.Finally, we have been able to observe the evolution of the role played by pinnipeds and otters in the indigenous socio-cultural context, which from being a vital resource, necessary for food, shelter and habitation, became, over the course of the 18th and 19th centuries, a commodity destined for inter-ethnic trade and commerce. This development will have major repercussions for these societies.

Niche partitioning occurs among coexisting populations to reduce the effects of competitive exclusion among species of similar niche. The aim of the present study is to verify the trophic niche partitioning and feeding behavior between two mustelids, the Giant otter and the Neotropical otter, through the dry and rainy season hydrologic of the Lower Xingu River. Our results suggest that the diets of both mustelids are composed primarily of fish of the family Anostomidae (Headstanders). Despite extensive niche overlap, our results indicate partitioning is facilitated by differences in niche breadth, with potential implications for conservation of both species in the case of declines in prey abundance and diversity. Both species inhabit an area recently impacted by completion of the Belo Monte Hydropower Plant, resulting in large changes to the hydrologic regime. Thus, our results provide important information for conservation efforts regarding the feeding behavior and co-occurrence of both species, as well as providing a baseline for monitoring future health of these mustelid populations. The present study is the first to test the hypothesis of niche partitioning between these two mustelids outside a protected area in the Amazon.

Understanding the diving behavior of semiaquatic mammals, particularly in relation to estimated aerobic dive limits and diet, is important to understand their adaptability and potential vulnerability to changes in prey type and distribution. The diving behavior of African clawless otters, Aonyx capensis, and spotted-necked otters, Hydrictis maculicollis, is poorly known, and no estimates of their dive performance in relation to targeted prey and calculated dive limits have been reported previously for freshwater environments. We investigated the diving behavior of both these otter species in freshwater environments within South Africa through video recordings of direct observations and subsequent video analyses where dive and recovery durations and dive function were recorded. African clawless otters were found to perform longer dives (mean ± SD = 26.9 ± 12.2 s), compared to spotted-necked otters (8.5 ± 7.6 s). African clawless otters showed substantial variation in dive durations, with the shortest dives sometimes lasting < 5 s, and the longest recorded dive being 70 s. The majority of spotted-necked otter dives lasted < 10 s, with the shortest recorded dive lasting 0.66 s and the longest recorded dive lasting 50.9 s. Spotted-necked otters performed different dive types that were evidently dependent on prey targeted, with dives targeting crabs (16.10 ± 1.91 s) being longer than dives targeting rainbow trout, Oncorhynchus mykiss (5.58 ± 0.17 s). The theoretical dive durations of African clawless otters were exceeded during play dives, while spotted-necked otters sometimes exceeded their theoretical dive durations when performing successful foraging dives. The results of this study suggest that spotted-necked otters can vary behavior in relation to prey and exceed theoretical dive duration during successful foraging dives to maximize the net rate of energy gain. Furthermore, when considering known individual-level dietary specialization and plasticity in these species, it may be predicted that dive behaviors are likely to vary substantially among individuals, and in relation to prey availability and localized habitat conditions.

We describe the population of the Еndangered sea otter Enhydra lutris on Urup Island, one of the main wildlife refuges in the southern Kuril Islands of Russia. We reviewed historical and local reports of the sea otter, identified its habitat around the island, and surveyed the coastal waters of the island in 2019. Sea otters were numerous on Urup Island in the past but were hunted excessively and almost exterminated by the 1950s. Since then, sea otter populations have increased, and as the island is almost uninhabited we expected otters to be numerous. This was not the case, and we estimated the total population to be 363 ± SE 126 individuals. Our observation of two skinned carcasses on the shore suggests the low numbers are a result of poaching for the illegal fur trade. The case of Urup Island demonstrates that sea otters require active conservation, as even on a remote island they remain threatened. Establishment of protected areas would be an effective conservation measure for this species, although the suppression of demand for sea otter fur is of the greatest importance.

The eastern shovelnose ray (Aptychotrema rostrata) is a medium-sized coastal batoid endemic to the eastern coast of Australia. It is the most common elasmobranch incidentally caught in the Queensland east coast otter trawl fishery, Australia’s largest penaeid-trawl fishery. Despite this, age and growth studies on this species are lacking. The present study estimated the growth parameters and age-at-maturity for A. rostrata on the basis of sampling conducted in southern Queensland, Australia. This study showed that A. rostrata exhibits slow growth and late maturity, which are common life-history strategies among elasmobranchs. Length-at-age data were analysed within a Bayesian framework and the von Bertalanffy growth function (VBGF) best described these data. The growth parameters were estimated as L0 = 193 mm TL, k = 0.08 year–1 and L∞ = 924 mm TL. Age-at-maturity was found to be 13.3 years and 10.0 years for females and males respectively. The under-sampling of larger, older individuals was overcome by using informative priors, reducing bias in the growth and maturity estimates. As such, the results can be used to derive estimates of natural mortality for this species.

Perceived as an indicator of the balance in wildlife and clean nature, the Eurasian otter (Lutra lutra L.) is near-threatened due to the fact that its fur is valuable, the increase in environmental pollution, the decrease in wetlands, the rivers in their habitats are turned into channels. There are 86 rainbow trout (Oncorhynchus mykiss) farms legally licensed by the Provincial Ministry of Agriculture and Forestry Mugla - Turkey. Since otter meets 70% of its nutrient need from fish, it is seen as a predatory species by aquaculture producers. For this reason, it is necessary to work on establishing otter habitats and breeding farms jointly with rainbow trout farmers in order to eliminate the negative effects of both rainbow trout farms and Eurasian otters. In this way, Eurasian otters that are near-threatened, will be saved and also a different contribution will be made to our economy.

Svenn, a wild otter, has become an Instagram celebrity with over 140,000 followers around the world. Svenn has his own YouTube channel and Facebook page. Moreover, in December 2020, NRK, an influential Norwegian TV channel, released a series entitled “Oteren Svenn” (Svenn, the Otter), consisting of ten episodes. In addition to all of this, Svenn has his own picturebook for children, which is entitled Svenn the Otter and the Magic Rock (Villseth & Sletten, 2020). This article presents the picturebook and analyzes three of its significant spreads. The aim is to uncover aspects of the sociocultural context in which Svenn – along with other characters – is portrayed by images and verbal language in the book, and to provide a short discussion of how the book may be used in English Language Teaching (ELT). Our analysis builds on tools from multimodal text analysis (Kress & van Leeuwen, 2005; van Leeuwen, 2005) and Narrative Intelligence (Mateas & Senger, 2003). The analysis focuses on the significance of the picturebook to represent participants in actions, the relationship between the book’s participants and the reader, and the value of presenting images and verbal text together. Our analysis also touches on some implications for ELT, on the potential that visual literacy can have in language teaching.

Bear identity exists as an understudied subgroup among gay, bisexual and other men who have sex with men (gbMSM). Given associations between Body Mass Index (BMI) and Bear identity, we examined prevalence estimates and effect modification between Bear identity, BMI, and cardiovascular health. Data is from February 2012–February 2018 and comes from a longitudinal-cohort of gbMSM in Metro Vancouver, recruited using respondent-driven sampling (RDS). We conducted univariable and multivariable logistic regression using RDS weighting. A total of 161 (21.3%) gbMSM self-identified as a Bear/Cub/Otter (BCO) and 48 (7.2%) gbMSM who identified as a BCO had a measured BMI ≥ 30. Multivariable results found non-BCO identity and a BMI ≥ 30 (aOR = 11.27; 95% CI = 2.88, 44.07) was associated with greater odds of history of cardiovascular health condition and/or associated risk factors compared to gbMSM who did not identify as a BCO and had a BMI < 30. The majority of gbMSM with BMI ≥ 30 identified as a BCO. However, BCO identity was not the most significant effect modifier for BMI on a history of a cardiovascular health condition and/or associated risk factors. Interventions should target all gbMSM with increased risk for cardiovascular disease and clinicians should be mindful of culturally sensitive prevention and care for gbMSM who identify as a BCO.

Bài báo này là một nghiên cứu bán thực nghiệm nhằm mục đích đánh giá hiệu quả của việc sử dụng ứng dụng Otter làm công cụ thực hành để nâng cao khả năng phát âm nói riêng và kỹ năng nói tiếng Anh nói chung cho sinh viên; đánh giá những lợi ích của ứng dụng và đưa ra kết luận có nên sử dụng ứng dụng này để làm công cụ cho sinh viên tự thực hành ngoài lớp học hay không. Đối tượng nghiên cứu là 40 sinh viên của một lớp khẩu ngữ tại Trường Ngoại ngữ - Đại học Thái Nguyên. Để thu thập dữ liệu, nhà nghiên cứu đã sử dụng bảng hỏi, bài kiểm tra và phỏng vấn. Kết quả của nghiên cứu cho thấy, việc sử dụng ứng dụng này để thực hành các bài tập bổ trợ giúp sinh viên cải thiện khả năng phát âm một cách đáng kể. Nghiên cứu kết luận rằng việc triển khai các bài tập bổ trợ với ứng dụng Otter trong quá trình học tập có tác động tích cực đến kỹ năng nói của sinh viên, đặc biệt là về phát âm.

The presence and strength of trophic cascades can be a function of the local abiotic environment and relative abundance of key species. The reintroduction and expansion of sea otters Enhydra lutris, a known keystone species in kelp ecosystems, in southeast Alaska provides a rare natural experiment to test the generality of a apex‐predator – seagrass trophic cascades across a broad spatial scale. We conducted an in‐depth seagrass community survey at 21 sites spanning ~100 km with variable sea otter presence to test for patterns of alternating abundance and direct relationships between species indicative of trophic cascades. Our analysis revealed some of the trophic relationships predicted by the apex predator–seagrass trophic cascades theory, including a strong negative relationship between sea otters and crabs and many of the expected relationships between nitrate, seagrass, epiphytes and epifauna. Other expected relationships within a trophic cascade, however, were not supported – including no relationship between crabs and epifauna, a critical link in the trophic cascade. Given the lack of evidence for all hypothesized direct relationships, we conclude that a sea otter mediated trophic cascade may not be present in southeast Alaska and could be due to local scale factors including the spatial heterogeneity, low resource availability and non‐linear food chains in southeast Alaska seagrass communities. However, correlation analyses suggest further interactions among biological and environmental variables in southeast Alaska seagrass communities, including a positive correlation between sea otters and seagrass biomass. These results suggest that the effects of recovering apex‐predator populations may not be generalizable across regions and spatial scales, highlighting a need for local assessment on the ecology and management of these populations.

Information on the feeding habits of species is essential to develop appropriate conservation actions. This study aimed to assess spatial and temporal variation in the diet of the Eurasian otter, Lutra lutra in the Anzali Wetland, through fecal and stable isotope analysis. Seven main prey items were observed in the analysis of 300 fresh spraints. The highest feeding index was observed for fish, followed by snakes. Among the fish species consumed, the index of preponderance of Prussian carp (Carassius gibelio) was the highest followed by pike (Esox lucius) and white bream (Blicca bjoerkna). Results of Shannon diversity index suggest spatial variation of species diversity within and between feeding items (p < 0.05); snakes, frogs, and oriental river prawn (Macrobrachium nipponense) showed a seasonal variation. The otter’s trophic level (TL) (3.79) was higher than the TLs of other Anzali Wetland predators, such as pike. Bayesian mixing model showed source proportion contributions of fish 49.5%, reptiles 16.7%, insects 14.8%, crustacean 10.5%, amphibians 4.3%, birds 4.1%, and mollusks 0.1%. When considering only fish species in the Bayesian mixing model, Prussian carp was the main fish prey in the otters’ diet accounting for 47%. Based on the results of this study, the Eurasian otter plays an important role in the ecology of the Anzali Wetland ecosystem even though it preys on exotic species, such as the Prussian carp and the oriental river prawn.

In the catchment of the River Segura (SE Spain), ongoing Eurasian otter (Lutra lutra) recovery and concurrent spread of human settlements are resulting in increasing otter records into urban areas. We analysed otter diet along a natural-to-urban gradient, with the main aim of assessing to which extent man-driven variation in food availability affects its feeding habits and how this secretive mustelid can thrive in apparently unsuitable habitats. From 2016 to 2019, we collected 521 spraints, monitoring 37 sampling stations (mean length ± SD = 0.5 ± 0.3 km). In natural areas, the percent cover of undisturbed banks was the highest, with the lowest number of water abstraction systems, whilst water pollution was the highest in urban areas. Introduced red swamp crayfish (Procambarus clarkii) and fish formed the bulk of otter diet. The two most preyed fish, Luciobarbus sclateri and Pseudochondrostoma polylepis, were among the most abundant species in the river, confirming the generalist feeding behaviour of the otter. The contribution of non-native fish was on average low, while invasive crayfish exceeded the overall importance of fish in all habitats except urban areas. Overall, diet data did not allow attesting food as a limiting resource for otters in urban areas. In contrast, marking intensity varied consistently with the natural-to-urban gradient (from 0.31 to 0.65 spraints/100 m in urban- and natural areas, respectively), suggesting that human disturbance (i.e. habitat modification and water pollution) may play a major role in shaping otter distribution.

Animal stone-handling behavior (SH) has been recorded in detail only in primates, mainly across macaque species. The purpose(s) of SH are still unknown, yet various hypotheses have been suggested, including that it is a misdirected behavior when hungry and/or a play behavior that aids individuals' motor and stone tool-use development. SH has also been observed across both wild and captive otter species, but no overview report of the extent of this behavior across otter species has been published yet. To fill this gap in the literature, we contacted wild and captive otter researchers and keepers to enquire directly on SH in the species they work with. We accepted anecdotal reports in this first review of the behavior. Using the reports and anecdotes thus obtained, we compiled the first list of otter species that show SH. We found that most (10 out of 13) of currently known otter species practice SH. Therefore, similarly to macaques, SH is also common in otters and occurs in the majority of species. Future studies should focus on replicating these findings and further investigating the potential functions and selection pressures of SH in otters and other animal species.

Neotropical otters have been scarcely studied at the northern edge of their distribution in Mexico. The species has nocturnal-twilight habits, and their principal food is fish and crustaceans. The aim of this work was to know the foraging habits of Neotropical otters (Lontra longicaudis) in two monitoring sites one lentic and the other one lotic systems of the Río San Lorenzo, Sinaloa México. From February 2009 to January 2010, we surveyed the area during the four seasons by walking 15 km of the river edge of Río San Lorenzo, and 15 km at the El Comedero reservoir. We collected 318 scats, 155 in the reservoir and 163 in the river. Fish were the most abundant prey item in both places, with a frequency of occurrence of 98.1 % in the river and 100 % in the reservoir. The percentage of occurrence varied largely in the other prey items in both places. Seven taxonomic groups compose their foraging habits in the river (relative frequency in parentheses): fish (64.3 %), insects (9.2 %), mollusks (6.8 %), birds (6.0 %), mammals (5.6 %), crustaceans (5.2 %) and fruits (2.8 %). Five taxonomic groups in the reservoir compose it: fish (65.1 %), birds (22.7 %), mammals (9.2 %), fruits (2.5 %) and insects (0.4 %). The most important fish in the diet belonged to the genus Oreochromis, which includes an introduced species. We conclude that the Neotropical otter is an opportunistic carnivore that preys mainly on fish, probably due to their high availability, but they also forage in other taxa that are available at Río San Lorenzo basin.

American mink Neovison vison is a semi-aquatic mustelid that has been introduced throughout Europe. Several attempts to eradicate this invasive species have been carried out since its spread. In the Iberian Peninsula, an eradication program has started since 2001, as part of the national action plan for the conservation of European mink Mustela lutreola. Proper detection is crucial for management, both for monitoring variation in mink abundance and prevent the recolonization of cleared areas. Mink scats can be confounded with those of several same-sized mustelids, and with the spraints of Eurasian otter Lutra lutra, which also occur along watercourses. However, these difficulties can be overcome by non-invasive genetic methods. With the aim of providing a cost-effective and reliable technique for differentiating mink scats from those of the largest possible number of species with morphologically similar scats, we tested the effectiveness of an already available faecal mtDNA-based PCR–RFLP method for distinguishing mink- and otter faeces. We then applied the method for analysing scats collected and identified in the field by trained surveyors for monitoring the success of mink control operations. The PCR–RFLP method clearly differentiated mink scats from those of otters, as restriction enzymes produced well-defined different patterns. Eighty-five percent of 94 faecal samples could be assigned to a mustelid species. Only three out of seven putative mink samples were confirmed, suggesting that the accuracy of the visual identification of scats is questionable and genetic methods are needed for the reliable assessment of the success of eradication programs.

As a top predator, the Eurasian otter (Lutra lutra) is an indicator of healthy freshwater ecosystems and a flagship species for conservation. Once widespread in China, the species is now distributed mainly in the upper reaches of the great rivers of western China. However, a lack of knowledge on local otter populations continues to hinder their conservation in China. Here, we conducted a detailed study on habitat use of Eurasian otters in Yushu City and Tangjiahe National Nature Reserve in western China using transect surveys. At both study sites, otters preferred to defecate on large rocks close to or protruding from the river and about 50 cm above the waterline. In Yushu, no spraints were found along the 5 km river bank section in the downtown area, with otters preferring sprainting sites with natural banks, riparian zones, and lower human population density. However, this pattern was not obvious at Tangjiahe, where river transformation and human disturbance are minor. Otter river use intensity was negatively correlated with elevation and human population density in Yushu in both seasons. In Tangjiahe, otter river use intensity was positively correlated with prey mass and flow rate and negatively correlated with human population in spring, but positively correlated with human population and negatively correlated with flow rate in autumn. These results reflect the flexible habitat use strategies of otters at different sites, underlining the necessity to study otters living in different regions and habitat types. We provide suggestions for river modification and call for more site-specific studies to promote otter conservation in China.

An eighteen-year-old female Eurasian otter became emaciated and died. Necropsy examination revealed nose and thoracic cutaneous masses, abdominal subcutaneous mass, and multiple nodules in the liver and lungs. Malignant melanoma was found in the nose cutaneous mass and to have metastasized to the liver, lungs, kidneys, adrenal glands, mammary glands and left mandibular lymph node. The neoplastic cells were labeled for vimentin, melanoma, and S100. The cutaneous mass in the thoracic area consisted of spindle shaped neoplastic epithelial cells and was diagnosed as trichoblastoma. Mammary gland adenoma was observed in the abdominal subcutaneous mass. This is the first report of primary three neoplasms of malignant melanoma, trichoblastoma and mammary gland adenoma in a Eurasian otter.

Numerous Miocene terrestrial mammal fossils have been discovered at the Grytsiv locality of Ukraine, but this is the first record of a fossil marine mammal at this site. Morphological analysis of the rostral portion of this middle-late Miocene (12.3–11.8 Ma) partial skull suggests that it belongs to the subfamily Phocinae. The small size and cranial morphology of this partial skull is compared with recent and fossil representatives of the extant subfamily Phocinae and the extinct subfamily Devinophocinae. Extinct and modern representatives of the extant subfamilies Cystophorinae and Monachinae were not incorporated in this study due to their extremely large size in comparison to this new find. This newly described skull belonged to a small-sized seal (likely similar in size to the modern sea otter based on the width of the rostrum) with an extremely short rostrum and several other diagnostic characters that differ from all other fossil and extant phocines. Due to the lack of preservation and fragility of fossil seal skulls, less than 20 have been described so far. This new skull is yet another example of an ancestral seal, supporting the suggestion that modern seals have become larger over their evolutionary history. Overall, any cranial information on fossil true seals is extremely important since it allows resolving contentious phylogenetic relationships between extinct and extant representatives of this group.

Post-import from the Republic of Indonesia to Japan in 2017, two juvenile, captive bred Asian small-clawed otters (Aonyx cinereus) exhibited gastrointestinal symptoms, including vomiting, diarrhea, and hematemesis, and died. One of them was examined postmortem. Microscopically, the small intestinal mucosa was necrotic with crypts lined by regenerating large epithelial cells. A gastric cardiac mucosal ulcerative lesion containing fungal yeasts and pseudohyphae morphologically indicated Candida spp. The lymph nodes exhibited marked lymphoid depletion. Canine parvovirus 2 (CPV-2) was isolated from an oral swab, and virus protein 2 (VP2) gene sequencing revealed new CPV-2a. To our knowledge, this is the first new CPV-2a infection report in Asian small-clawed otters. This infection should be considered in gastrointestinal symptom-related cases in this species.

The composition of estuarine fish fauna is dynamic and complex. Despite the variation in fish fauna in estuaries, it is possible to observe some species associated with microhabitats. The assemblage composition of these communities is apparently derived from habitat selection. The aim of this study was to assess the structure of the demersal fish fauna of the Paranaguá Bay and its relationship with biotic and abiotic factors. To this end, monthly collections were conducted using an otter trawl, from October 1999 to September 2000, at five sites in the shallow infralittoral. Biotic (organic matter, and invertebrates) and abiotic factors (salinity, temperature, pH, dissolved oxygen, seston, and nutrients) were recorded during sampling. A total of 6,623 individuals were captured, belonging to 2 species of Chondrichthyes and 53 species of Actinopterygii (26 families). Sciaenidae was the most representative in terms of richness, with 11 species, and Ariidae was the most representative in terms of abundance. The catfish Cathorops spixii was the most abundant species, representing 21 % of the entire catch. There were significant differences in the composition and abundance of the fish fauna among the studied areas, as evidenced by the Shannon-Wiener diversity index. Such differences seem to be related to the complexity of habitats, which occur due to different types of bottom cover found at each sampling site. The abiotic variables indicated little influence on the structure of the fish assembly. These results contribute to a better understanding of the fish fauna from the shallow infralittoral areas of the Paranaguá Bay, and provide data to decision makers for better implementation of management and conservation measures.

This paper studies the mongoose (ichneumon) as a predator widely represented in the fowling and fishing scenes, chasing birds in a papyrus thicket. From the predynastic period, several scholars attempted to attest the mongoose among other animals prevailed at this time, which had been called different names in ancient Egyptian language. It also deals with specific features of mongoose in order to differentiate it from other similar animals such as Otter and Weasel. The paper reviews many tomb scenes of the mongoose as a predator of young birds in their nests, with several scenes, causing the belief that the ancient Egyptian trying to tame it. Besides, it discusses the unrealistic appearance of the papyrus thicket in which the animals were preyed, as a fictional rather than a true reflection of wildlife. furthermore, the religious meaning interpreted these scenes. Especially, all related scenes were found in a funerary context and therefore one expects them to have a religious dimension, even though this was not explicitly stated.