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Students with difficulty in maintaining grade-level performance at the Model Secondary School for the Deaf (Washington, DC) are learning mathematics and science skills using "The Voyage of the Mimi," a 13-segment video series and associated educational materials that detail a scientific expedition which is studying humpback whales. Team teaching has allowed maximal use of the materials. (DB)

Suggested are activities about whales for children in schools not near the ocean. Activities designed to pique students' interest in whales and to investigate the size, breathing, buoyancy, and feeding strategies of whales are discussed. (CW)

Provides background information (in outline form) on the bottlenose dolphin. Includes facts on characteristic anatomical and physiological features and highlights behavioral and communication patterns of dolphins. Also includes an explanation of ecolocation. (ML)

Presents information on sea mammals, including definitions and characteristics of cetaceans, pinnipeds, and sirenians. Contains descriptions of the teaching activities "Whale Music,""Draw A Whale to Scale,""Adopt a Sea Mammal," and "Sea Mammal Sleuths." (TW)

Lists journal articles and publications dealing with marine mammals. Entries (from the Sawyer Marine Resources Collection) also include references to marine reptiles and fish. (ML)

Looks at Melville's narrative construction of "onion-like...layers of truth" that combine romance and textbook, presents critics' discussion and scholars' treatment of the cetological information present in the text, offers an explanation for the lack of recognition due to the nonfictional parts of "Moby Dick." (JK)

Introduces a new glossary of aquatic mammals representing recent taxonomic revisions. Describes its design, which consists of the glossary proper, listing the scientific name of each entry followed by its English and French equivalents, and of two indexes, listing other common names for the same entries referred back to the scientific term. (MES)

Presented is a discussion on why people should study whales. Background information, learning activities appropriate for different subject areas, and whale-related teaching materials are included. (DC)

Describes public whale-watching expeditions initiated to cover expenses of the Okeanos Ocean Research Foundation, a group investigating whales and their migratory patterns off the shores of Long Island, New York. Discusses history of whales in the region and recent cetacean conservation efforts. (NEC)

Describes a variety of teaching strategies to prepare a class for a whale watching field trip. Guidelines for recording a sighting, pictures and statistics for commonly and/or occasionally seen whales, and hints for avoiding sea sickness are included. (DH)

Describes two-week summer workshops on evolution, adaptation, and behavior of whales, conducted for children by Cold Spring Harbor Whaling Museum (New York), and culminating in creation of life-size sand sculptures of whales. Provides selected list of periodicals, teaching materials, identification guides, records, and societies devoted to whales and cetacean preservation. (NEC)

Marine heat waves (MHWs), extended periods of unusually high ocean temperatures that significantly impact marine ecosystems, are prevalent in the Southern California Bight (SCB), increased thermal stratification has intensified these events over recent decades, affecting California sea lions by disrupting prey availability, leading to malnutrition and higher mortality rates. Rising atmospheric CO2 levels have exacerbated this issue, contributing to the warming of surface waters. Climate models predict that MHWs will continue to increase in frequency, severity, and duration, posing further risks to marine life. Despite the presence of a significant sea lion colony off the coast of San Diego, little research has been conducted on MHWs in the SCB impact on the local sea lion population. This research examines various aspects of MHWs at San Diego, including defining MHWs, historical occurrences, current trends, and their implications for California sea lions, while exploring potential policy and mitigation strategies to protect Southern California's marine ecosystems. Daily sea Surface Temperature (SST) measurements from La Jolla Scripps Pier (1916-2023) are used to quantify local MHWs relative to a shifting baseline (i.e., one that adjusts for the long-term warming trend), and to a fixed baseline (i.e., the warming trend alone increases MHW occurrences). We investigate critical questions about MHW evolution and duration, considering the continuous warming of the oceans. We consider what the two definitions of MHWs imply for upwelling and nutrient supply to the ocean surface, and the implications for California sea lion prey availability. We identify future research priorities, particularly improved measures of sea lion population counts, and the need for better indicators of MHW impacts beyond SST.

Extremes in organismal size have broad interest in ecology and evolution because organismal size dictates many traits of an organisms biology. There is particular fascination with identifying upper size extremes in the largest vertebrates, given the challenges and difficulties of measuring extant and extinct candidates for the largest animal of all time, such as whales, terrestrial non-avian dinosaurs, and extinct marine reptiles. The discovery of Perucetus colossus, a giant basilosaurid whale from the Eocene of Peru, challenged many assumptions about organismal extremes based on reconstructions of its body weight that exceeded reported values for blue whales (Balaenoptera musculus). Here we present an examination of a series of factors and methodological approaches to assess reconstructing body weight in Perucetus, including: data sources from large extant cetaceans; fitting published body mass estimates to body outlines; testing the assumption of isometry between skeletal and body masses, even with extrapolation; examining the role of pachyostosis in body mass reconstructions; addressing method-dependent error rates; and comparing Perucetus with known physiological and ecological limits for living whales, and Eocene oceanic productivity. We conclude that Perucetus did not exceed the body mass of todays blue whales. Depending on assumptions and methods, we estimate that Perucetus weighed 60-70 tons assuming a length 17 m. We calculated larger estimates potentially as much as 98-114 tons at 20 m in length, which is far less than the direct records of blue whale weights, or the 270 ton estimates that we calculated for body weights of the largest blue whales measured by length.

The marine environment presents challenges for wound healing in cetaceans, despite their remarkable recovery abilities with minimal infections or complications. However, the molecular mechanism underlying this efficient wound healing remains underexplored. To better understand the molecular mechanisms behind wound healing in cetaceans, we investigated the evolutionary patterns of 37 wound healing‐related genes in representative mammals. We found wound healing‐related genes experience adaptive evolution in cetaceans: (1) Three extrinsic coagulation pathway‐related genes—tissue factor (F3), coagulation factor VII (F7), and coagulation factor X (F10)—are subject to positive selection in cetaceans, which might promote efficient hemostasis after injury; positive selection in transforming growth factor‐beta 2 (TGF‐β2), transforming growth factor‐beta 3 (TGF‐β3), and platelet‐derived growth factor D (PDGFD), which play immunological roles in wound healing, may help cetaceans enhance inflammatory response and tissue debridement. (2) Coagulation factor XII (F12) is the initiation factor in the intrinsic coagulation pathway. It had a premature stop codon mutation and was subjected to selective stress relaxation in cetaceans, suggesting that the early termination of F12 may help cetaceans avoid the risk of vascular blockage during diving. (3) Fibrinogen alpha chain (FGA) and FIII, which were detected to contain the specific amino acid substitutions in marine mammals, indicating similar evolutionary mechanisms might exist among marine mammals to maintain strong wound‐healing ability. Thus, our research provides further impetus to study the evolution of the wound healing system in cetaceans and other marine mammals, extending knowledge of preventing coagulation disorder and atherosclerosis in humans. [ABSTRACT FROM AUTHOR]

Icebreaker vessels in the Canadian Arctic are used to monitor and maintain open shipping lanes during summer and fall. Icebreaker operating routes often overlap with important habitats of endemic Arctic marine mammals, leading to potential interactions and disturbance. In this study, we examined the frequency, proximity, and duration of encounter events between narwhals (Monodon monoceros) and icebreaker vessels in Tasiujaq (Eclipse Sound), Nunavut, an important summering area for this species. We combined tracking data from 25 narwhals equipped with satellite telemetry devices in Tasiujaq between 2016 and 2018 with automatic identification system (AIS) data for the same period from 7 icebreaker vessels. We defined an encounter event between a narwhal and an icebreaker as the total consecutive occurrences of an individual within 50 km of a vessel within 1 hour. For all years combined, 17 out of 25 narwhals had at least 1 encounter with an icebreaker and all 7 icebreakers were involved in at least 1 encounter. The closest distance (closest point of approach) recorded was <1 km and the longest cumulative duration of encounter events for 1 narwhal with 1 icebreaker was 121.6 hours (n = 27 encounter events over 17 days). Proximity and continuous exposure of narwhals to high levels of noise are a key concern when considering short‐ and long‐term effects on behavior and fitness of this species. [ABSTRACT FROM AUTHOR]

The relative importance of various sensory modalities can shift in response to evolutionary transitions, resulting in changes to underlying gene families encoding their reception systems. The rapid birth‐and‐death process underlying the evolution of the large olfactory receptor (OR) gene family has accelerated genomic‐level change for the sense of smell in particular. The transition from the land to sea in marine mammals is an attractive model for understanding the influence of habitat shifts on sensory systems, with the retained OR repertoire of baleen whales contrasting with its loss in toothed whales. In this study, we examine to what extent the transition from a terrestrial to a marine environment has influenced the evolution of baleen whale OR repertoires. We developed Gene Mining Pipeline (GMPipe) (https://github.com/AprilJauhal/GMPipe), which can accurately identify large numbers of candidate OR genes. GMPipe identified 707 OR sequences from eight baleen whale species. These repertoires exhibited distinct family count distributions compared to terrestrial mammals, including signs of relative expansion in families OR10, OR11 and OR13. While many receptors have been lost or show signs of random drift in baleen whales, others exhibit signs of evolving under purifying or positive selection. Over 85% of OR genes could be sorted into orthologous groups of sequences containing at least four homologous sequences. Many of these groups, particularly from family OR10, presented signs of relative expansion and purifying selective pressure. Overall, our results suggest that the relatively small size of baleen whale OR repertoires result from specialisation to novel olfactory landscapes, as opposed to random drift. [ABSTRACT FROM AUTHOR]

Simple Summary: Marine mammals in the Mediterranean are among the most exposed globally to mercury, persistent organic pollutants (legacy or emerging), and micro- and nanoplastics. Moreover, the semi-enclosed basin is highly sensitive to climate change, with enhanced water warming, possible changes in primary productivity and food webs, and a predictable increasing remobilization of soil- and sediment-bound persistent pollutants. In this context, this review discusses the physico-chemical and bio-ecological processes driving the exceptional bioaccumulation of mercury in Mediterranean cetaceans and possible future trends. Marine mammals detoxify and store Hg in the liver and other organs as insoluble crystals, but this process can deplete the biological pool of an essential element such as selenium and expose adult cetaceans to infectious and autoimmune diseases. Although difficult to assess, an even more serious threat to Mediterranean cetaceans may be the concomitant and remarkable accumulation of synthetic organic pollutants. The NW Mediterranean has been declared a cetacean sanctuary, yet the whales and dolphins living there tend to have the highest concentrations of most persistent pollutants. Therefore, we emphasize the adoption of all available measures to mitigate anthropogenic pressures and studies to evaluate the biological effects of chronic and concurrent exposure to persistent environmental pollutants. Despite decreasing anthropogenic mercury (Hg) emissions in Europe and the banning and restriction of many persistent organic pollutants (POPs) under the Stockholm Convention, Mediterranean marine mammals still have one of the highest body burdens of persistent pollutants in the world. Moreover, the Mediterranean basin is one of the most sensitive to climate change, with likely changes in the biogeochemical cycle and bioavailability of Hg, primary productivity, and the length and composition of pelagic food webs. The availability of food resources for marine mammals is also affected by widespread overfishing and the increasing number of alien species colonizing the basin. After reporting the most recent findings on the biogeochemical cycle of Hg in the Mediterranean Sea and the physico-chemical and bio-ecological factors determining its exceptional bioaccumulation in odontocetes, this review discusses possible future changes in the bioavailability of the metal. Recent ocean–atmosphere–land models predict that in mid-latitude seas, water warming (which in the Mediterranean is 20% faster than the global average) is likely to decrease the solubility of Hg and favor the escape of the metal to the atmosphere. However, the basin has been affected for thousands of years by natural and anthropogenic inputs of metals and climate change with sea level rise (3.6 ± 0.3 mm year−1 in the last two decades), and the frequency of extreme weather events will likely remobilize a large amount of legacy Hg from soils, riverine, and coastal sediments. Moreover, possible changes in pelagic food webs and food availability could determine dietary shifts and lower growth rates in Mediterranean cetaceans, increasing their Hg body burden. Although, in adulthood, many marine mammals have evolved the ability to detoxify monomethylmercury (MMHg) and store the metal in the liver and other organs as insoluble HgSe crystals, in Mediterranean populations more exposed to the metal, this process can deplete the biological pool of Se, increasing their susceptibility to infectious diseases and autoimmune disorders. Mediterranean mammals are also among the most exposed in the world to legacy POPs, micro- and nanoplastics, and contaminants of emerging interest. Concomitant exposure to these synthetic chemicals may pose a much more serious threat than the Se depletion. Unfortunately, as shown by the literature data summarized in this review, the most exposed populations are those living in the NW basin, the main feeding and reproductive area for most Mediterranean cetaceans, declared a sanctuary for their protection since 2002. Thus, while emphasizing the adoption of all available approaches to mitigate anthropogenic pressure with fishing and maritime traffic, it is recommended to direct future research efforts towards the assessment of possible biological effects, at the individual and population levels, of chronic and simultaneous exposure to Hg, legacy POPs, contaminants of emerging interest, and microplastics. [ABSTRACT FROM AUTHOR]

Simple Summary: In this work, we documented the presence of two neurotrophins NGF (Nerve Growth Factor) and BDNF (Brain-Derived Neurotrophic Factor) in the pancreas of two species of marine mammals, Tursiops truncatus (common bottlenose dolphin) and Otaria flavescens (South American sea lion). Pancreas samples were provided by the Mediterranean Marine Mammal Tissue Bank of the Department of Comparative Biomedicine and Food Science of the University of Padua (Italy). These two growth factors are well-known mediators for maintaining the survival of neurons but also exert a metabotrophic effect. The localization in the pancreas of bottlenose dolphins and sea lions of these neurotrophins could help to better understand how these marine animals handle metabolic challenges in their adaptation to ocean life. In this study, we have investigated the immunolocalization of NGF (Nerve Growth Factor) and BDNF (Brain-Derived Neurotrophic Factor) in the pancreas of two species of marine mammals: Tursiops truncatus (common bottlenose dolphin), belonging to the order of the Artiodactyla, and Otaria flavescens (South American sea lion), belonging to the order of the Carnivora. Our results demonstrated a significant presence of NGF and BDNF in the pancreas of both species with a wide distribution pattern observed in the exocrine and endocrine components. We identified some differences that can be attributed to the different feeding habits of the two species, which possess a different morphological organization of the digestive system. Altogether, these preliminary observations open new perspectives on the function of neurotrophins and the adaptive mechanisms of marine mammals in the aquatic environment, suggesting potential parallels between the physiology of marine and terrestrial mammals. [ABSTRACT FROM AUTHOR]

Marine monitoring efforts are increasingly supported by opportunistic shipboard surveys. However, opportunistic survey methods often require adaptation to suit the vessel and the operations being conducted onboard. Whilst best-practice techniques for surveying marine wildlife on vessels of opportunity are yet to be established, testing and development of alternative methods can provide means for capturing ecological information in otherwise under-surveyed areas. Explicitly, survey methods can be improved while baseline ecological data for new regions are gathered simultaneously. Herein, we tested different survey approaches on a vessel of opportunity in a remote offshore area where little is known about the community composition of top-order marine vertebrate predators: western and south-western Tasmania, Australia. We found that continuous surveys provide greater species counts than structured "snapshot" surveys over the course of a voyage, but that structured surveys can be more practical when managing factors such as observer fatigue. Moreover, we provide a baseline dataset on the marine vertebrate community encountered in western and south-western Tasmania. This information will be critically important for industry and conservation management objectives, and is key to our understanding of the offshore ecosystem around Tasmania. [ABSTRACT FROM AUTHOR]

In this paper, we present the first machine learning package developed specifically for fish calls identification within a specific range (0-500Hz) that encompasses four Caribbean grouper species: red hind (E. guttatus), Nassau (E. striatus), yellowfin (M. venenosa), and black (M. bonaci). Because of their ubiquity in the soundscape of the grouper's habitat, squirrelfish (Holocentrus spp.) sounds along with vessel noise are also detected. In addition themodel is also able to separate grouper species call types. This package called FADAR, the Fish Acoustic Detection Algorithm Research is a standalone user-friendly application developed in Matlab™. The concept of FADAR is the product of the evaluation of various deep learning architectures that have been presented in a series of published articles. FADAR is composed of a main algorithmthat can detect all species calls including their call types. The architecture of this model is based on an ensemble approach where a bank of five CNNs with randomly assigned hyperparameters are used to form an ensemble of classifiers. The outputs of all five CNNs are combined by a fusion process for decisionmaking. At the species level, the output of the multimodel is thus used to classify the calls in terms of their types. This is done by species specific deep learningmodels that have been thoroughly evaluated in the literature on the species concerned here, including transfer learning for red hind and yellowfin groupers and custom designed CNN for Nassau grouper, which has a greater number of known call types than the other species. FADARwasmanually trained on a diversity of data that span various regions of the Caribbean Sea and also two recorder brands, hydrophone sensitivities, calibrations and sampling rates, including a mobile platform. This strategy has conferred FADAR substantive robustness to a diversity of noise level and sources that can be found in the grouper calls frequency band such as vessels and marine mammals. Performance metrics based on sensitivity (recall) and specificity showed the same performance level for both balanced and unbalanced datasets and at locations not used in the training set. [ABSTRACT FROM AUTHOR]

In a recent paper titled Expert range maps of global mammal distributions harmonised to three taxonomic authorities , Marsh et al. (2022) introduced a series of new geographic range maps for all extant species of mammals and made these maps available on the Map of Life (MoL) website (www.mol.org). The title of the paper and inclusion of over 140 prominent mammalogists and biogeographers as coauthors strongly suggested that these new range maps were carefully vetted. However, when examining the maps of Marsh et al. (2022) on the MoL web platform, we found a variety of serious problems, including, but not limited to: range exaggerations (inclusion of substantial geographic areas not represented by specimen records or verified observations); range maps that are geographically shifted so that species are shown as occurring in areas in which they do not, and not occurring in areas in which they do (and in some cases, these new maps do not even encompass the type locality of a species); range maps that simply omit peripheral populations of conservation concern; and range maps for fully marine mammals (i.e. those that do not spend any time on land) that include large swaths of both insular and continental landmasses. Overall, we evaluated the new "expert" mammal range maps on the MoL platform for 78 species (retrieved between 31 March 2022 and 1 April 2023) and show that there are serious, systemic problems with these maps, and that these problems are both geographically and taxonomically widespread. As such, we caution researchers to carefully review and evaluate the range maps of Marsh et al. (2022) on the MoL before using them for any research purpose—including conservation, biogeographical, and macroecological analyses of mammals. [ABSTRACT FROM AUTHOR]

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]

The use of Pop‐up Satellite Archival Tags (PSATs) has provided considerable new information about the behaviour of migrating (silver) eels (Anguilla spp.) at sea, with 9 of 19 recognised species or subspecies tagged to date. However, such studies often reported premature tag detachment and relatively high rates of predation. Since 2000, several PSAT‐tagged New Zealand longfin eels, Anguilla dieffenbachii, were released to understand migratory behaviour and location of potential spawning grounds. Of 20 PSAT‐tagged eels released in 2019, all tags detached prematurely, but 7 (58%) were likely eaten or injured by predators 1–81 days after release. Two eels were probably eaten by sperm whales, whereas other tagged eels were likely eaten by lamniform and non‐lamniform sharks, and southern bluefin tuna. Because of the high rate of predation, we recommend that future releases should be from smaller catchments or offshore. [ABSTRACT FROM AUTHOR]

Terrestrially breeding marine predators have experienced shifts in species distribution, prey availability, breeding phenology, and population dynamics due to climate change worldwide. These central‐place foragers are restricted within proximity of their breeding colonies during the breeding season, making them highly susceptible to any changes in both marine and terrestrial environments. While ecologists have developed risk assessments to evaluate climate risk in various contexts, these often overlook critical breeding biology data. To address this knowledge gap, we developed a trait‐based risk assessment framework, focusing on the breeding season and applying it to marine predators breeding in parts of Australian territory and Antarctica. Our objectives were to quantify climate change risk, identify specific threats, and establish an adaptable assessment framework. The assessment considered 25 criteria related to three risk components: vulnerability, exposure, and hazard, while accounting for uncertainty. We employed a scoring system that integrated a systematic literature review and expert elicitation for the hazard criteria. Monte Carlo sensitivity analysis was conducted to identify key factors contributing to overall risk. We identified shy albatross (Thalassarche cauta), southern rockhopper penguins (Eudyptes chrysocome), Australian fur seals (Arctocephalus pusillus doriferus), and Australian sea lions (Neophoca cinerea) with high climate urgency. Species breeding in lower latitudes, as well as certain eared seal, albatross, and penguin species, were particularly at risk. Hazard and exposure explained the most variation in relative risk, outweighing vulnerability. Key climate hazards affecting most species include extreme weather events, changes in habitat suitability, and prey availability. We emphasise the need for further research, focusing on at‐risk species, and filling knowledge gaps (less‐studied hazards, and/or species) to provide a more accurate and robust climate change risk assessment. Our findings offer valuable insights for conservation efforts, given that monitoring and implementing climate adaptation strategies for land‐dependent marine predators is more feasible during their breeding season. [ABSTRACT FROM AUTHOR]

Observations and models indicate that climate warming is associated with the loss of dissolved oxygen from the ocean. Dissolved oxygen is a fundamental requirement for heterotrophic marine organisms (except marine mammals) and, since the basal metabolism of ectotherms increases with temperature, warming increases organisms' oxygen demands. Therefore, warming and deoxygenation pose a compound threat to marine ecosystems. In this study, we leverage an ecophysiological framework and a compilation of empirical trait data quantifying the temperature sensitivity and oxygen requirements of metabolic rates for a range of marine species ("ecotypes"). Using the Community Earth System Model Large Ensemble, we investigate how natural climate variability and anthropogenic forcing impact the ability of marine environments to support aerobic metabolisms on interannual to multi-decadal timescales. Warming and deoxygenation projected over the next several decades will yield a reduction in the volume of viable ocean habitats. We find that fluctuations in temperature and oxygen associated with natural variability are distinct from those associated with anthropogenic forcing in the upper ocean. Further, the joint temperature–oxygen anthropogenic signal emerges sooner than temperature and oxygen independently from natural variability. Our results demonstrate that anthropogenic perturbations underway in the ocean will strongly exceed those associated with the natural system; in many regions, organisms will be pushed closer to or beyond their physiological limits, leaving the ecosystem more vulnerable to extreme temperature–oxygen events. [ABSTRACT FROM AUTHOR]