Articles tagged with Marine Mammals
The interim update to the State of the World's Migratory Species report warns that 49% of migratory species populations are declining, with 24% facing extinction, due to habitat loss and overexploitation. The report highlights the need for coordinated international action to address these threats and protect migratory species.
Research finds that humpback whales face a higher risk of getting entangled in fishing equipment during years with lower availability of cool-water habitat. The Habitat Compression Index can predict ocean conditions up to a year in advance, suggesting its potential as an early warning system for fishery management decisions.
A solitary bottlenose dolphin in the Venetian Lagoon is monitored by researchers who assess its remarkable adaptation to urban surroundings. The team highlights the need for human behavior management to ensure the dolphin's welfare, rather than focusing on wildlife protection measures.
Researchers have identified three previously unknown genotypes of Helicobacter bacteria in pygmy sperm whales stranded along the southeastern US coast. The discovery raises new questions about microbial pathogens on ocean health and their impact on vulnerable species.
Research shows Australian sea lion pups can learn foraging behaviour from their mothers, a discovery that could aid conservation efforts. The pups adapt to their mother's foraging style, changing their feeding patterns and habitats.
A recent study found that seals near glacier fronts have fuller stomachs, indicating intense feeding activity. This discovery has implications for Arctic marine ecosystems as glaciers retreat and habitats disappear.
A SFU study found that warmer temperatures in the Arctic can cause malnutrition in seals, intensifying risks to Inuit food security and northern ecosystems. The research analyzed samples from 38 Arctic ringed seals and found high levels of persistent contaminants such as PCBs and mercury.
Scientists captured rare view of beaked whales by listening to their natural sounds, revealing deep-diving behavior. The study provides the first detailed description of Gervais' beaked whale dives anywhere in the world.
Researchers use advanced technology to pinpoint locations of elusive beaked whales diving to the seafloor off the Louisiana coast. The study reveals new insights into their behavior and detection range, shedding light on these mysterious creatures.
Despite sea ice losses, Svalbard polar bears' body conditions have improved due to increased fat reserves and access to land-based prey. The study found that the number of ice-free days in the Barents Sea region increased, but the mean body condition index of adult polar bears rose following 2000.
A global study reveals signs of complete extinction in the Canary Islands, where a previously undetected mass mortality event was identified in mid-2022. The affected species is no longer capable of reproducing, potentially leading to local extinction with severe ecological consequences.
Researchers studied diet changes among three whale species, fin, humpback, and minke whales, over 28 years. The study found that whales are adapting their feeding habits in response to limited resource availability and increased competition.
New research reveals that Indigenous communities in southern Brazil hunted large whales 5,000 years ago, long before previously thought. The study provides strong evidence of active hunting and sheds light on the economies, technologies, and lifeways of postglacial societies along the Atlantic coast of South America.
A Harvard-designed bio-logger captures high-fidelity audio of sperm whale codas, which are later analyzed by machine learning models to uncover structured communication. Recent results show that sperm whales have their own alphabet and use vowels and diphthongs in their language.
Researchers found that killer whales and Pacific white-sided dolphins cooperate while hunting salmon in British Columbia waters. The orcas use dolphin echolocation to locate Chinook salmon, which the dolphins then scavenge for food scraps after the orcas eat their share.
A new species of ancient sea cow has been discovered in Qatar, revealing that sea cows have shaped the Arabian Gulf's seagrass ecosystems for over 20 million years. The fossil site, Al Maszhabiya, yielded more than 170 different locations containing sea cow fossils.
Researchers observed a female Antarctic leopard seal exhibiting postmortem attentive behavior, or PAB, where she cared for her deceased pup for over 20 days. This unique phenomenon is rare in marine mammals and sheds light on the complex behaviors of these apex predators.
A new study by UH Mānoa-Led research revealed 25 distinct underwater vocalizations in Hawaiian monk seals, including a previously undocumented foraging call and a novel 'combinational' communication strategy. The findings provide a baseline for understanding the acoustic world of this endangered species.
Research reveals West Coast transient killer whales are two distinct subpopulations, differing in diet, hunting grounds and social behavior. The inner coast transients are expert navigators of nearshore inlets, while the outer coast whales thrive in deep canyons and rugged underwater terrain.
Researchers at the University of British Columbia have identified eight per- and polyfluoroalkyl substances (PFAS) in B.C. sea otters, with concentrations three times higher on average in otters near major cities and shipping routes. This proximity effect highlights the need for government regulation to prevent PFAS spread.
A new study reveals that different prey within a single species can provide vastly different levels of nutrition for marine predators. This variation can lead to predators consuming more prey than necessary, highlighting the importance of understanding prey quality in maintaining ecosystem balance.
Researchers tested a popular evolutionary theory by comparing maternal length and fetal sex in over 100,000 whales. They found that the fetal sex ratio skews female for longer body size, suggesting that female calves benefit more from heritable fitness than males do. The findings contradict the Trivers-Willard hypothesis.
Scientists observed Hector's dolphins' subsurface behaviors, which may increase their risk of bycatch. The study sheds light on the conservation efforts for this critically endangered species.
Beaked whales are recorded in the Foz do Amazonas Basin using passive acoustic monitoring, demonstrating their first documentation in Brazilian waters. The study contributes to understanding cetacean biodiversity and showcases the effectiveness of acoustic monitoring for categorizing elusive sea creatures.
A new study finds that sargassum seaweed can significantly slow down sea turtle hatchlings in Florida, increasing their risk of predation and heat exposure. Researchers found that even small amounts of sargassum can impede hatchlings' progress, with leatherbacks taking 54% longer to crawl through light sargassum.
A global review highlights the need for better tools to understand juvenile fish habitats, which are facing increased pressure from various factors. The study recommends incorporating metrics like growth, survival, and contribution rates to assess habitat quality.
Researchers found river otter scat containing parasites that infect prey, indicating otters may play a crucial role in shaping their ecosystems. The study also discovered diverse diets and invasive species among the otters' meals.
Researchers have identified a previously undocumented class of PFAS in the blubber of killer whales, accumulating in fat-rich blubber. This discovery challenges the long-held assumption that PFAS primarily bind to proteins and accumulate in liver or blood.
Scientists have discovered a new species of ancient whale, Janjucetus dullardi, from a 26-million-year-old fossil found in Victoria's Surf Coast. The discovery reveals a fast, sharp-toothed predator with a compact body and big eyes.
The study analyzed the northbound migration of northern fur seals, revealing that they concentrate foraging activity along continental shelf-breaks and near anticyclonic eddies. The findings provide new insights into the seals' response to oceanographic conditions and highlight the importance of long-term monitoring in understanding th...
Researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute have developed a multi-sensor biologging tag on the whitespotted eagle ray, enabling long attachment times and detailed data collection. The study provides insights into the rays' behavior, habitat use, and social interactions.
A recent study found that the 2014-2016 Northeast Pacific marine heatwave caused unprecedented ecological disturbance, resulting in widespread kelp and seagrass declines and mass mortality events. The research highlights cascading impacts on species interactions, plankton communities, and offshore ocean productivity.
A team of whale experts discovered that southern resident killer whales regularly use lengths of bull kelp as tools to groom each other during social interactions. The whales fashion the tools by breaking off the ends of kelp stalks and then press them against a partner, rolling them between their bodies for long periods.
Killer whales have been observed detaching kelp stalks and using them to massage each other's backs, a behavior dubbed "allokelping". This social bonding behavior may promote skin health and strengthen relationships among the whales.
The Barents Sea system – gateway to the changing Arctic book documents six years of interdisciplinary research on the Barents Sea. Researchers used various platforms, including drones, satellites, and underwater robots, to collect data and make predictions about future changes.
Researchers have discovered that dolphin brains process echolocation as a form of tactile sensation, using neural pathways similar to those found in the cerebellum. This study provides insight into the unique auditory processing abilities of dolphins, which are distinct from other marine mammals.
A global research team tracked over 100 species of marine animals, revealing key migration patterns and hotspots critical for conservation. The study, MegaMove, uses satellite data to inform a new blueprint for ocean conservation, highlighting the need for targeted mitigation efforts.
Wild animals studying seals' extreme environments could provide answers to pressing problems in human reproductive health. Seals' unique physiology offers insights into managing gestational diabetes and improving IVF success rates.
An 11-year-old Asian small-clawed otter developed left-sided paralysis after a fall, but improved with treatment for a suspected fibrocartilaginous embolus. Follow-up MRI showed a diminished lesion one year later.
A study reveals widespread overlap between feeding grounds for seabirds, marine mammals, and regions with high wind potential. Researchers propose developing risk maps to predict conflicts and recommend expanding marine protected areas and strengthening spatial planning tools.
Researchers used a novel approach to estimate megalodon's body length and shape, finding it closer in shape to a lemon shark or large whale. The study suggests the prehistoric predator may have reached about 80 feet in length and weighed an estimated 94 tons.
Researchers propose that timing hypothesis explains the mystery of missing blue whale calves, where births occur in fall and winter, and calves are weaned before returning to feeding areas. This explanation offers alternative insight into high pregnancy rates vs. low sightings of mother-calf pairs.
Baleen whale species that flee from killer whales produce calls at deep frequencies undetectable to their predators, while others sing higher-frequency songs that are easily heard. This 'flight' vs 'fight' difference influences all aspects of baleen whale behavior, from migration patterns and communication to mating and feeding habits.
The study highlights the potential of novel techniques to collect and analyse plankton data more efficiently, filling knowledge gaps and generating complete pictures of plankton dynamics. However, integrating old and new methods is crucial to ensure accurate assessments of marine biodiversity.
A team of researchers from Florida Atlantic University, San Diego Natural History Museum, and SeaWorld San Diego collaborate to digitize a rare vaquita skeleton, providing a valuable resource for conservation efforts. The scans resulted in three terabytes of data and will be used to create replicas for public display and education.
A new study examines legislation and conservation efforts in the Mediterranean region to protect over 80 shark and ray species. The research reveals substantial differences in countries' efforts, with European Union countries leading implementation of measures.
Researchers used drone imagery to measure calf growth and maternal body condition in Hawaiʻi and Alaska, finding larger females produced larger calves. Humpback whales lose significant weight during lactation, with mothers losing nearly 214 pounds per day.
A new study led by the University of Washington found that only about 7% of areas at highest risk for whale-ship collisions have any measures in place. The team identified high-risk regions, including coastal areas along the Mediterranean, Americas, southern Africa, and parts of Asia, where whales and ships are most likely to meet.
Researchers suggest that manatees may have only become a permanent fixture in Florida after Europeans colonization began, contradicting the common assumption of their long history in the state. The study suggests that warming waters and human activities may have encouraged the manatees to stay and breed.
A study has found that H5N1 highly pathogenic avian influenza spread efficiently among marine mammals, leading to a devastating decline in elephant seal colonies. The virus adapted to marine mammal species, showing the need for increased surveillance and research cooperation in the region.
Researchers discovered that bottlenose dolphins use the open mouth facial expression to signal playfulness and that they mirror each other's expressions 33% of the time. This finding suggests that visual communication plays a crucial role in shaping complex social interactions in marine mammals.
Researchers analyzed DNA in fecal samples to determine the diet of Alaska and southern resident killer whales. They found that both populations prefer salmon, but differ in when they switch to hunting other fish species. The study provides key insights into the delicate balance between regional abundance of different fish species.
A study by Cornell University researchers found that the public only discovers 58% of decoy dolphin carcasses, suggesting a higher number may be dying but not reported. The results point to habitats where staff should focus their efforts and highlight the importance of accurate estimates for understanding cause-specific deaths.
A Bronze Age purple dye workshop has been found on the Greek island of Aegina, featuring tools, ceramics, and snail shells that reveal the production process. The site provides insights into Mycenaean culture and trade during the Late Bronze Age.
A study found that tool use among sea otters allows access to larger prey, reducing tooth damage. Female otters, which are more likely to use tools, can consume prey up to 35% harder than males.
A new study has confirmed that killer whales take only one breath between dives, providing insights into their unique physiological habits. The researchers used drone footage and biological data from tags to gather information on the animals' habits, revealing that residents spend most of their time making shallow dives.
A study analyzing canned salmon from 1979 to 2021 found stable anisakid worm levels in coho and sockeye salmon, while pink and chum salmon showed a rise. This suggests that the marine food web has adapted to changing conditions, with rising parasite levels indicating potential ecosystem shifts.
Researchers at the University of British Columbia have discovered a new population of killer whales in the Northeastern Pacific, with distinct physical characteristics and a diet that includes marine mammals and sea turtles. The orcas were identified through shark-bitten scars and observations by fishermen and birding enthusiasts.
A new study reveals that marine heat waves disrupt the ocean food web in the northeast Pacific Ocean, shifting energy and impacting predators and prey. Gelatinous zooplankton thrive during heat waves, drawing energy out of the ecosystem and potentially affecting fish and marine mammals.
The Belt Sea population of harbour porpoises is declining at a rate of 2.7% annually due to by-catch, deoxygenation, pollution, and lack of fish. Limiting net usage or using acoustic alarms on nets could be an immediate solution to mitigate the issue.