Aquatic Mammals: A Guide to Marine and Freshwater Species

Aquatic mammals are a diverse group of vertebrate species that spend all or a significant portion of their lives in water. This guide covers the major lineages, including cetaceans (whales, dolphins, and porpoises), pinnipeds (seals, sea lions, and walruses), sirenians (manatees and dugongs), and several semi-aquatic species such as otters, hippos, and polar bears. The content is designed for students, researchers, life-science professionals, and informed general readers who need a structured overview of aquatic mammal diversity, adaptations, and conservation considerations.

Defining Aquatic Mammals

Aquatic mammals are mammals that have evolved to live in marine or freshwater environments. Unlike fish, they breathe air, are warm-blooded, give birth to live young, and nurse their offspring with milk. The transition from land to water has occurred independently in multiple mammalian lineages, resulting in a range of adaptations that vary by degree of aquatic dependence.

Fully aquatic mammals spend their entire lives in water and include cetaceans and sirenians. These species cannot survive on land and have evolved streamlined bodies, flippers, and tail flukes for propulsion. Semi-aquatic mammals divide their time between land and water and include pinnipeds, otters, hippos, and polar bears. These species retain the ability to move on land but are highly specialized for swimming and foraging in aquatic environments.

The distinction between aquatic and semi-aquatic mammals matters for understanding their biology, management, and conservation needs. Fully aquatic species face different physiological challenges than semi-aquatic species, particularly regarding thermoregulation, sleep, and locomotion.

At a Glance: Major Aquatic Mammal Groups

Cetaceans: Whales, Dolphins, and Porpoises

Cetaceans are the most fully adapted aquatic mammals. This group includes approximately 90 species distributed across all oceans and several major river systems. They are divided into two main subgroups: mysticetes (baleen whales) and odontocetes (toothed whales, dolphins, and porpoises).

Baleen Whales

Baleen whales include the largest animals on Earth, such as the blue whale, fin whale, and humpback whale. Instead of teeth, these species possess baleen plates made of keratin that filter small prey from the water. They typically feed on krill, small fish, and copepods. Baleen whales are generally migratory, moving between high-latitude feeding grounds and low-latitude breeding grounds.

Toothed Whales and Dolphins

Toothed whales include dolphins, porpoises, sperm whales, and beaked whales. These species have teeth and hunt individual prey such as fish, squid, and other marine mammals. Many toothed whales use echolocation to navigate and locate prey in dark or turbid waters. The family Delphinidae, which includes bottlenose dolphins and orcas, is the most species-rich and widely studied group of aquatic mammals.

River Dolphins

Several dolphin species live exclusively in freshwater river systems. These include the Amazon river dolphin, Ganges River dolphin, Indus River dolphin, and Yangtze finless porpoise. River dolphins face high extinction risk due to habitat degradation, pollution, and limited research attention. According to a review in Animal Health Research Reviews, cetaceans such as the Yangtze finless porpoise, Irrawaddy dolphin, Ganges River dolphin, Amazon River dolphin, and Indus River dolphin are at higher risk of extinction because of lack of knowledge and research, resulting in insufficient information regarding their conservation status, management, and policies (Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation).

Pinnipeds: Seals, Sea Lions, and Walruses

Pinnipeds are semi-aquatic marine mammals characterized by flippers and streamlined bodies. They include three families: Phocidae (true seals), Otariidae (fur seals and sea lions), and Odobenidae (walruses). Pinnipeds breed and rest on land or ice but forage exclusively in water.

True seals lack external ear flaps and move on land by undulating their bodies. Fur seals and sea lions have visible external ears and can rotate their hind flippers forward for more efficient terrestrial movement. Walruses are distinguished by their long tusks and are found in Arctic and sub-Arctic waters.

Pinnipeds exhibit diverse foraging strategies and diving capabilities. Some species, such as elephant seals, can dive to depths exceeding 1,500 meters and remain submerged for over an hour. Their blood cell morphology and physiology are adapted for prolonged hypoxia and high-pressure environments. A comparative review of blood cell morphology, ultrastructure, and cytochemistry in marine mammals notes that erythrocytes in marine mammals are often relatively large and display species-specific differences in shape and indices that may contribute to differences in oxygen transport physiology and blood rheology (Blood cell morphology, ultrastructure and cytochemistry in marine mammals: a narrative comparative review).

Sirenians: Manatees and Dugongs

Sirenians are fully aquatic herbivorous mammals that inhabit warm coastal waters, rivers, and estuaries. The group includes three species of manatees and one species of dugong. Sirenians have paddle-like forelimbs, a horizontally flattened tail, and no hind limbs. They feed on seagrasses and aquatic vegetation.

Manatees are found in the Americas and West Africa, while dugongs are distributed across the Indo-Pacific region. Sirenians are slow-moving and spend much of their time resting and feeding in shallow waters. Their low metabolic rate and herbivorous diet distinguish them from other aquatic mammal groups.

Semi-Aquatic Mammals

Several mammalian species are semi-aquatic, meaning they depend on aquatic habitats for foraging but retain significant terrestrial activity. These species provide insight into the evolutionary transition from land to water.

Otters

Otters belong to the family Mustelidae and are found on every continent except Australia and Antarctica. River otters inhabit freshwater systems, while sea otters are marine specialists along the North Pacific coast. Otters have dense fur, webbed feet, and streamlined bodies that enable efficient swimming. Sea otters use tools, such as rocks, to crack open shellfish and have the densest fur of any mammal.

Hippopotamuses

Hippopotamuses are large semi-aquatic mammals native to Africa. They spend daylight hours in rivers and lakes to keep their skin moist and avoid overheating, then graze on land at night. Despite their bulky appearance, hippos are capable swimmers and can hold their breath for several minutes underwater.

Polar Bears

Polar bears are classified as marine mammals because they depend on sea ice for hunting seals. They are powerful swimmers and can cover long distances in open water. Polar bears are the largest land carnivores and are adapted to the Arctic environment with thick blubber and dense fur.

Semiaquatic Adaptations and Energetics

The biomechanics and energetics of semi-aquatic mammals differ markedly from fully aquatic species. A review in Physiological and Biochemical Zoology explains that semiaquatic mammals swim by paddling, which is inefficient compared to the use of oscillating hydrofoils by aquatic mammals. Semiaquatic mammals swim at the water surface and experience greater resistive force augmented by wave drag compared to submerged aquatic mammals. A dense, nonwettable fur insulates semiaquatic mammals, whereas aquatic mammals use a layer of blubber. The fur, while providing insulation and positive buoyancy, incurs a high energy demand for maintenance and limits diving depth. Blubber contours the body to reduce drag, serves as an energy reserve, and suffers no loss in buoyancy with depth (Biomechanics and energetics in aquatic and semiaquatic mammals: platypus to whale).

Adaptations for Aquatic Life

Aquatic mammals have evolved a suite of morphological, physiological, and behavioral adaptations that enable them to thrive in water. These adaptations vary by lineage and degree of aquatic dependence.

Locomotion

Fully aquatic mammals use oscillating hydrofoils for propulsion. Cetaceans move their tail flukes vertically, while sirenians move their tails vertically as well. Pinnipeds use their foreflippers for steering and their hind flippers for propulsion. Semi-aquatic mammals such as otters use undulatory body movements combined with paddling limbs.

Thermoregulation

Water conducts heat approximately 90 times more effectively than air, creating a significant thermoregulatory challenge for aquatic mammals. Fully aquatic species rely on blubber, a thick layer of insulating fat that also serves as an energy reserve. Semi-aquatic species such as otters and fur seals use dense fur to trap air and retain heat. The review on biomechanics and energetics notes that aquatic mammals live in thermally challenging environments where conductive heat loss is approximately 90 times greater than in air, requiring them to be moving most of the time (Biomechanics and energetics in aquatic and semiaquatic mammals: platypus to whale).

Diving Physiology

Aquatic mammals have evolved remarkable diving capabilities. They can store oxygen in muscle tissue via myoglobin, tolerate high levels of carbon dioxide, and redirect blood flow to vital organs during dives. Their blood cells exhibit adaptations for oxygen transport. The comparative review of blood cell morphology notes that erythrocytes in marine mammals are often relatively large and display species-specific differences that may contribute to differences in oxygen transport physiology (Blood cell morphology, ultrastructure and cytochemistry in marine mammals: a narrative comparative review).

Sensory Biology

Aquatic mammals have adapted their sensory systems for underwater perception. Cetaceans and some pinnipeds use echolocation to navigate and hunt in dark or turbid waters. Their auditory systems are highly specialized for underwater hearing. The sensory biology of aquatic mammals is a distinct field of study that examines how these species perceive their environment through vision, hearing, touch, and chemoreception (Sensory biology of aquatic mammals).

Sleep Patterns

Aquatic mammals exhibit unique sleep patterns that differ from terrestrial mammals. A review in Neuroscience Bulletin explains that aquatic mammals have either radically reduced or completely eliminated rapid eye movement (REM) sleep. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals, and completely absent or negligible in aquatic mammals. Aquatic mammals are obligate swimmers that must surface at regular intervals for air. They have evolved unihemispheric sleep, during which one brain hemisphere remains awake while the other rests, allowing them to swim and rest simultaneously. A condition that immobilizes muscle activity and suspends thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals (Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?).

Research on dream mentation in mammals suggests that cetaceans are the least likely mammalian group to experience vivid dream mentation due to the morphophysiological independence of their cerebral hemispheres. If dream mentation only occurs during REM sleep, it is unlikely that monotremes, cetaceans, and otariid seals while at sea have the potential to experience dream mentation (Do all mammals dream?).

Vocalization and Communication

Marine mammals have evolved sound production mechanisms that manage vocalizing and breathing in an aquatic environment. A perspective article in BMC Biology notes that intervals in rhythmic cetacean vocalizations cover a remarkable temporal range, from less than a millisecond in porpoise burst pulses to 10 seconds in sperm whale slow clicks. Many cetaceans demonstrate temporally coordinated social behavior, while pinnipeds express high variability in vocal plasticity and social behavior (Marine mammals as models for charting the evolution of social vocal rhythm).

Health and Disease Considerations

Aquatic mammals are susceptible to a range of infectious diseases, environmental contaminants, and anthropogenic threats. Understanding these health challenges is important for conservation and management.

Brucellosis in Aquatic Mammals

Brucellosis is a bacterial infection that affects a wide range of aquatic mammals. A comprehensive meta-analysis published in Veterinaria Italiana documented the presence of Brucella infections in a large number of aquatic mammals, affecting wild animals living in oceans, seas, lakes, and rivers within both northern and southern hemispheres. The study identified at least 130 species of aquatic mammals as potential hosts for Brucella spp. Brucella ceti and Brucella pinnipedialis represent the main marine Brucella species, with documented enzootic potential. The prevalence of brucellosis in males (30.42%) was significantly higher than in females (18.59%). The family Delphinidae was the most studied among aquatic mammals, with a total prevalence of 39.66%. The meta-regression analysis showed a strong and significant association between the prevalence of Brucella spp. in mammals and water temperature, while no significant correlation was found with water salinity. There is no systematic veterinary inspection and no global or local requirements for the monitoring of brucellosis in aquatic mammals (A comprehensive meta-analysis of Brucella infections in aquatic mammals).

Hemotropic Mycoplasma

Hemotropic Mycoplasma species are uncultivable bacteria that infect mammals, including humans. A study published in Emerging Infectious Diseases detected a potentially novel hemoplasma species in blood samples from wild river dolphins in the Amazon River Basin, Brazil. Further investigation could determine pathogenicity and zoonotic potential of the detected hemoplasma (Hemotropic Mycoplasma spp. in Aquatic Mammals, Amazon Basin, Brazil).

Pneumonia and Pollution

Pneumonia is one of the leading causes of mass mortalities of cetaceans. Anthropogenic activities, including the discharge of effluents and runoffs containing pesticides, heavy metals, and other contaminants, can harm exposed fauna and flora. Pollutants can directly affect animal behavior, disrupt cellular systems, and impair the immune system. The review in Animal Health Research Reviews discusses stress-induced pneumonia and immunosuppression, pneumonia-caused mass mortalities of aquatic mammals, and vaccination in wildlife with a specific focus on aquatic mammals (Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation).

Microplastic Pollution

Microplastic pollution poses increasing health risks to aquatic mammals. A review in the Journal of King Saud University Science examines the adverse health effects of increasing microplastic pollution on aquatic mammals, including ingestion, tissue accumulation, and potential toxicological impacts (The adverse health effects of increasing microplastic pollution on aquatic mammals).

Chemical Defensome Erosion

Marine mammals have experienced convergent gene loss in their chemical defensome, the molecular systems that detect, detoxify, and eliminate foreign compounds. A study published in 2026 demonstrates large-scale gene loss in chemical defensome genes of cetaceans, as well as smaller scale gene loss in pinnipeds and sirenians. Gene loss occurred predominantly in phase I and phase II biotransformation enzymes, including CYPs, FMOs, SULTs, and GSTs. The transition to aquatic environments, often accompanied by changes in feeding habits, led to convergent loss of chemical defensome genes. These findings suggest that adaptation to marine life involves trade-offs in detoxification capacity that may have significant implications for species responses to increasing chemical pollution in present-day ocean environments (Convergent gene erosion in the chemical defensome of marine mammals).

Conservation Priorities and Threats

Aquatic mammals face numerous threats, including habitat loss, climate change, pollution, and human disturbance. Conservation planning requires integrating species status information with evolutionary history to identify priority areas and species.

Phylogenetic Conservation Priorities

A global spatial analysis of phylogenetic conservation priorities for aquatic mammals combined information on species status from the IUCN Red List with information on evolutionary history from phylogenetic trees. The study calculated two measures of conservation priorities for 127 aquatic mammals and identified 22 conservation priority areas distributed primarily along coastal waters in both northern and southern hemispheres. While thousands of marine protected areas have been established in recent years, only 11.5% of conservation priority areas overlap with existing marine protected areas. All phylogenetic conservation priority areas identified in this study have also been proposed to be important by other independent studies using different prioritization criteria (Global Spatial Analyses of Phylogenetic Conservation Priorities for Aquatic Mammals).

Diversification Rates

Research on diversification rates in marine mammals challenges the conventional view that marine ecosystems inherently constrain species diversification. A study published in 2026 found that marine mammals do not exhibit lower diversification rates than non-marine mammals, and may even exhibit higher rates depending on the phylogenetic framework. Taxonomy, particularly family, is the dominant predictor of diversification rate variation among mammals instead of the ecological realm. Diversification rate appears negatively correlated with body mass in marine mammals and with range size in non-marine mammals (Do Marine Mammals Diversify More Slowly Than Non-Marine Mammals?).

Offshore Wind Farms

Anthropogenic structures in the marine environment alter the availability and distribution of food for marine animals. A study of predation events at offshore wind farms in Scotland found that six Atlantic cod were predated by a marine mammal close to or in the vicinity of turbine foundations. The detection of tags at multiple turbines within a relatively short period after consumption suggests the targeted use of turbine foundations as foraging sites where prey fish are known to aggregate. The bias in predation of cod over haddock, and evidence for the cod being of higher energetic quality, provides rare evidence for prey selection by a marine mammal predator (Evidence of predation events by marine mammals at offshore wind farms).

Traditional Folk Medicine

Aquatic mammals have been used in traditional folk medicine across various cultures. A global analysis examines the use of aquatic mammals in traditional folk medicine, documenting the species involved and the cultural practices associated with their use (Aquatic Mammals Used in Traditional Folk Medicine: A Global Analysis).

Records and Measurements in Aquatic Mammal Research

Research on aquatic mammals relies on systematic data collection and standardized measurement protocols. Key measurements include body morphometrics, blood parameters, behavioral observations, and acoustic recordings.

Body Morphometrics

Standard body measurements for aquatic mammals include total length, girth, flipper length, and body mass. These measurements are used to assess growth, body condition, and nutritional status. For cetaceans, measurements are typically taken from stranded or captured animals. For pinnipeds, measurements may be taken during tagging or health assessment programs.

Blood Parameters

Hematological analysis provides valuable information about the health and physiological status of aquatic mammals. The comparative review of blood cell morphology notes that leukocyte morphology and cytochemical characteristics vary considerably among species, potentially reflecting phylogenetic background, ecological influences, and other biological or methodological factors. Cytochemical staining patterns are not consistent across species, highlighting the need for species-specific reference data and caution in extrapolating from terrestrial mammals (Blood cell morphology, ultrastructure and cytochemistry in marine mammals: a narrative comparative review).

Lactation Costs

Estimating lactation costs is important for understanding the energetic demands of reproduction in marine mammals. A study published in PLOS ONE used published estimates of mass-specific milk intake rates and milk energy density from marine mammals and taxonomically related terrestrial mammals to examine how these variables changed as a function of the percentage of time into the lactation interval. Daily mass-specific milk intake rates declined between the start and end of lactation for all taxonomic groups, but the rate of decline was much steeper for ursids, artiodactyls, and mustelids than for otariids or phocids. Cetaceans have higher mass-specific milk intake rates early in lactation compared to most other species, which then rapidly decline during the first 10-25% of the lactation interval. Such differences may be an adaptation to a fully aquatic lifestyle (Predicting daily lactation costs of marine mammals for use in bioenergetic models).

Common Failure Patterns in Aquatic Mammal Research and Management

Several recurring challenges limit the effectiveness of aquatic mammal research and conservation programs.

Insufficient Baseline Data

Many aquatic mammal species lack basic information on population size, distribution, and life history. The review on pneumonia in endangered aquatic mammals notes that species such as the Yangtze finless porpoise, Irrawaddy dolphin, Ganges River dolphin, Amazon River dolphin, and Indus River dolphin are at higher risk of extinction because of lack of knowledge and research, resulting in insufficient information regarding their conservation status, management, and policies (Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation).

Methodological Heterogeneity

Comparative studies of aquatic mammals are limited by uneven taxonomic coverage, small sample sizes, and methodological heterogeneity among studies. The blood cell morphology review identifies key knowledge gaps including the functional implications of cytochemical diversity, the molecular mechanisms underlying hematological variation, and the lack of data for many taxa, particularly mysticetes (Blood cell morphology, ultrastructure and cytochemistry in marine mammals: a narrative comparative review).

Limited Monitoring Programs

There is no systematic veterinary inspection and no global or local requirements for the monitoring of brucellosis in aquatic mammals. The meta-analysis on Brucella infections highlights the need for standardized diagnostic methods for the implementation of efficient screening and monitoring programs (A comprehensive meta-analysis of Brucella infections in aquatic mammals).

Habitat Loss and Degradation

Major threats to aquatic mammals include the loss and alteration of habitats due to human intervention, mainly deforestation and other land-use changes. The study of mammals in the Pantanal notes that local diversity and number of individuals of wild rodents and marsupials rely on the offering of ecological resources and behavioral specialization to microhabitat components. Mammals respond to seasonal shrinking-and-expansion of habitats due to flooding regimes (Terrestrial and aquatic mammals of the Pantanal).

Professional Escalation Criteria

Researchers, wildlife managers, and veterinarians working with aquatic mammals should escalate concerns to appropriate authorities under specific circumstances.

Disease Outbreaks

Reports of unusual mortality events, including mass strandings or die-offs, should be reported to relevant wildlife health authorities. The presence of Brucella infections in aquatic mammals, with documented enzootic potential, warrants monitoring and investigation (A comprehensive meta-analysis of Brucella infections in aquatic mammals).

Zoonotic Potential

Detection of pathogens with potential zoonotic transmission, such as hemotropic Mycoplasma species, should trigger further investigation to determine pathogenicity and zoonotic potential (Hemotropic Mycoplasma spp. in Aquatic Mammals, Amazon Basin, Brazil).

Conservation Emergencies

Species at high risk of extinction, particularly river dolphins and other poorly studied cetaceans, require urgent conservation intervention. The lack of knowledge and research on these species limits the development of effective management policies (Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation).

Environmental Contamination

Evidence of chemical pollution impacts on aquatic mammals, including the erosion of chemical defense capabilities, should be reported to environmental protection agencies. The findings on convergent gene erosion in marine mammals suggest that adaptation to marine life involves trade-offs in detoxification capacity that may have significant implications for species responses to increasing chemical pollution (Convergent gene erosion in the chemical defensome of marine mammals).

Frequently Asked Questions

What is the difference between aquatic and semi-aquatic mammals?

Aquatic mammals spend their entire lives in water and cannot survive on land. This group includes cetaceans (whales, dolphins, porpoises) and sirenians (manatees, dugongs). Semi-aquatic mammals divide their time between land and water and include pinnipeds (seals, sea lions, walruses), otters, hippos, and polar bears. Semi-aquatic species retain the ability to move on land but are highly specialized for swimming and foraging in aquatic environments.

Are dolphins mammals?

Yes, dolphins are mammals. They belong to the order Cetacea and share all defining mammalian characteristics, including being warm-blooded, breathing air through lungs, giving birth to live young, and nursing their offspring with milk. Dolphins are classified as toothed whales (odontocetes) and are closely related to porpoises and other whales.

What are the main groups of marine mammals?

The main groups of marine mammals are cetaceans (whales, dolphins, porpoises), pinnipeds (seals, sea lions, walruses), sirenians (manatees, dugongs), and marine-dwelling carnivores such as sea otters and polar bears. Some classifications also include the marine otter and the Galapagos fur seal as marine mammals.

How do aquatic mammals sleep without drowning?

Aquatic mammals have evolved unihemispheric sleep, during which one brain hemisphere remains awake while the other rests. This allows them to continue swimming and surface for air while sleeping. Research indicates that aquatic mammals have either radically reduced or completely eliminated REM sleep, which is characterized by muscle atonia and suspended thermoregulation, conditions that are not suitable for obligate swimmers (Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?).

What adaptations allow aquatic mammals to stay warm in cold water?

Aquatic mammals use two primary strategies for thermoregulation in water. Fully aquatic species such as cetaceans and sirenians rely on blubber, a thick layer of insulating fat that also serves as an energy reserve. Semi-aquatic species such as otters and fur seals use dense, nonwettable fur that traps air and provides insulation. Water conducts heat approximately 90 times more effectively than air, creating a significant thermoregulatory challenge (Biomechanics and energetics in aquatic and semiaquatic mammals: platypus to whale).

Which aquatic mammals live in freshwater?

Several aquatic mammal species live exclusively in freshwater environments. These include river dolphins such as the Amazon river dolphin, Ganges River dolphin, and Indus River dolphin, as well as the Yangtze finless porpoise. Manatees can inhabit both marine and freshwater habitats, and river otters are found in freshwater systems across multiple continents.

What diseases affect aquatic mammals?

Aquatic mammals are susceptible to various infectious diseases, including brucellosis caused by Brucella ceti and Brucella pinnipedialis, hemotropic Mycoplasma infections, and pneumonia. A meta-analysis documented Brucella infections in at least 130 species of aquatic mammals, with the family Delphinidae being the most studied (A comprehensive meta-analysis of Brucella infections in aquatic mammals). Pneumonia is one of the leading causes of mass mortalities of cetaceans (Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation).

Why are river dolphins at high risk of extinction?

River dolphins face high extinction risk due to habitat degradation, pollution, and limited research attention. According to a review in Animal Health Research Reviews, cetaceans such as the Yangtze finless porpoise, Irrawaddy dolphin, Ganges River dolphin, Amazon River dolphin, and Indus River dolphin are at higher risk of extinction because of lack of knowledge and research, resulting in insufficient information regarding their conservation status, management, and policies (Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation).

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References and Further Reading

• NCBI Literature Resources. National Center for Biotechnology Information.
• PubMed. National Library of Medicine.
• A comprehensive meta-analysis of Brucella infections in aquatic mammals.. Veterinaria italiana, 2022.
• Sensory biology of aquatic mammals.. Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology, 2013.
• Sleep in Aquatic Mammals.. Handbook of behavioral neuroscience, 2019.
• Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?. Neuroscience bulletin, 2012.
• Pneumonia in endangered aquatic mammals and the need for developing low-coverage vaccination for their management and conservation.. Animal health research reviews, 2020.
• Do all mammals dream?. The Journal of comparative neurology, 2020.
• Biomechanics and energetics in aquatic and semiaquatic mammals: platypus to whale.. Physiological and biochemical zoology : PBZ, 2000.
• Hemotropic Mycoplasma spp. in Aquatic Mammals, Amazon Basin, Brazil.. Emerging infectious diseases, 2022.
• Predicting daily lactation costs of marine mammals for use in bioenergetic models.. 2026.
• Marine mammals as models for charting the evolution of social vocal rhythm.. 2026.
• Convergent gene erosion in the chemical defensome of marine mammals. 2026.
• Do Marine Mammals Diversify More Slowly Than Non-Marine Mammals?. 2026.
• Blood cell morphology, ultrastructure and cytochemistry in marine mammals: a narrative comparative review.. 2026.
• Evidence of predation events by marine mammals at offshore wind farms. 2026.
• Global Spatial Analyses of Phylogenetic Conservation Priorities for Aquatic Mammals. 2016.
• An Annotated Checklist of Monogeneans (Platyhelminthes, Monogenea) from Aquatic Vertebrates in Peru: A Review of Diversity, Hosts and Geographical Distribution. Animals, 2024.
• Aquatic Mammals Used in Traditional Folk Medicine: A Global Analysis. 2013.
• Terrestrial and aquatic mammals of the Pantanal.. Brazilian journal of biology = Revista brasleira de biologia, 2011.
• Annotated List of Wetlands of International Importance Kenya. 2019.
• The adverse health effects of increasing microplastic pollution on aquatic mammals. Journal of King Saud University Science, 2022.
• Evolutionary analysis of genes associated with the sense of balance in semi-aquatic mammals. BMC Ecology and Evolution, 2025.

This article is educational and does not replace institutional policy, professional advice, or applicable safety and regulatory requirements.