marine mammals | University of Hawaiʻi System News /news News from the University of Hawaii Mon, 30 Mar 2026 20:32:32 +0000 en-US hourly 1 /news/wp-content/uploads/2019/04/cropped-UHNews512-1-32x32.jpg marine mammals | University of Hawaiʻi System News /news 32 32 28449828 New tech detects deadly whale, dolphin diseases /news/2026/03/30/new-tech-detects-disease/ Mon, 30 Mar 2026 19:00:48 +0000 /news/?p=230831 UH researchers have developed a portable, rapid test to detect deadly diseases in whales and dolphins directly on the beach.

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people standing by testing machine
Researchers from Taiwan and the UH Stranding and Whale Lab tested the new portable detector on Sand Island, Oʻahu.

A breakthrough in marine mammal health surveillance can now detect deadly diseases in whales and dolphins in oceans, beaches and remote locations, thanks to new research from the University of 鶹ý at Mānoa.

working in lab
The portable unit delivers results in about an hour, leading to faster decision-making during mass stranding events.

The UH Health and Stranding Lab at the (CTAHR) worked together with international researchers to validate a portable, field-deployable molecular diagnostic tool for Cetacean Morbillivirus (CeMV). The study was published in .

Rapid detection in the field

CeMV has caused mass deaths of thousands of marine animals globally. Traditionally, detecting such pathogens required sending samples to specialized laboratories, often resulting in delays of weeks to months.

“This is the first application of a field-deployable system for rapid testing for whales and dolphins,” said Kristi West, director of the UH Health and Stranding Lab. “It breaks down barriers to detection because it can be used remotely, even without a traditional lab nearby.”

The portable unit delivers results in about an hour, aiding decision-making during mass stranding events. It is designed for hot, humid environments, making it essential for detecting outbreaks early and potentially preventing larger epidemics. The system uses high-speed testing to provide rapid, on-site results. It proved effective across multiple divergent strains from 鶹ý, Europe and Brazil, even in archived tissues up to 28 years old.

“We want to train others so we can increase what we know about disease in many other areas of the world,” West said.

Global collaboration and training

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To ensure this technology reaches those who need it most, UH researchers hosted a workshop in Honolulu with Professor Wei-Cheng Yang from National Taiwan University’s Veterinary School to train stranding responders and scientists from across the Pacific.

Participants included staff from the Taiwanese Cetacean Society, and representatives from the 鶹ý Department of Land and Natural Resource’s Division of Aquatic Resources, NOAA Fisheries, the U.S. Geological Survey’s National Wildlife Health Center, biologists from Guam and Saipan and CTAHR graduate students.

During the workshop, researchers ran tests on known positive and negative samples for diseases impacting dolphins and Nene, the endemic Hawaiian goose. The Taiwanese team also shared their insights from a mass stranding of 11 pygmy killer whales they had responded to just days before arriving in 鶹ý, which resulted in the successful release of seven whales.

The project is supported by U.S. Pacific Fleet Environmental Readiness Division and a joint zoonotic disease grant with the state of Ჹɲʻ’s Department of Land and Natural Resources and involves collaborators from Taiwan, the Philippines, Spain, and Brazil.

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Disease and trauma found in majority of whale, dolphin strandings /news/2025/12/21/whale-dolphin-strandings/ Sun, 21 Dec 2025 18:00:00 +0000 /news/?p=227244 UH researchers analyzed 272 stranding investigations of 20 cetacean (whale and dolphin) species between 2006 and 2024.

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dolphins jumping
(Photo credit: Robin W Baird, Cascadia Research)

From land–borne pathogens to high–speed vessel strikes, Pacific whales and dolphins are caught in a “perfect storm” where human-caused trauma and infectious diseases were found in more than 65% of investigated strandings.

by University of 鶹ý at Mānoa researchers provides insights into the threats whales and dolphins face in the Pacific Islands.

whale swimming
(Photo credit: Jordan K Lerma, Cascadia Research)

Based on 272 stranding investigations of 20 cetacean species between 2006 and 2024, the study provides foundational data to better manage and conserve 鶹ý’s whales and dolphins.

“Dolphins and whales are sentinels of ocean health—we need to understand why these animals die to help others live,” said Kristi West, director of the UH Health and Stranding Lab at the .

Disease is prevalent

Over 18 years, scientists examined more than three-quarters of the stranded whales and dolphins to understand why they died. Most cases (62%) were linked to diseases, and about half of those animals were in poor body condition due to long-term illness.

Infectious agents proved to be a significant threat, affecting 11 different species, including striped dolphins and Longman’s beaked whales. Two of the most concerning pathogens were morbillivirus and brucella, which can cause serious brain and lung problems in marine mammals.

Toxoplasmosis—a parasite that infects warm-blooded animals and spreads through cat feces across the environment—was responsible for the deaths of two spinner dolphins and one bottlenose dolphin.

Trauma linked to humans

The study revealed that 29% of all strandings were linked to anthropogenic (human-caused) trauma. Vessel strikes were a significant risk, resulting in fatal vertebral and skull fractures for seven individuals, including two pygmy sperm whales, two humpback whale calves, a goose-beaked whale, a spinner dolphin and a striped dolphin.

Interactions with marine debris and fisheries were confirmed as fatal in multiple cases, including:

  • A sperm whale died from plastic and fishery debris blocking its stomach.
  • A bottlenose dolphin died after a fishhook tore into it.

Public reporting urged

In the Pacific Islands, most dolphins and whales die at sea, and recovery rates are very low. Each stranding examination provides stakeholders with valuable information about what is happening to these animals and their ecosystem. Public reporting is critical to understanding threats to marine mammal health.

Sightings of dead or distressed marine mammals can be reported to the statewide NOAA Marine Wildlife Hotline at (888) 256-9840, toll-free.

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鶹ýcalculates survival needs of deep-diving Hawaiian pilot whales /news/2025/11/13/hawaiian-pilot-whales/ Thu, 13 Nov 2025 23:57:26 +0000 /news/?p=225330 A new study found an average adult whale must eat 142 squid daily to survive, scaling up to 416 million squid annually for the entire population.

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An aerial view of 鶹ý short-finned pilot whales at the surface. (Photo credit: HIMB Marine Mammal Research Program)

For the first time, scientists have calculated a detailed “energetic budget” for 鶹ý‘s short-finned pilot whales, revealing what it takes to power their extreme, 800-meter (2,600-feet) dives for food.

A new study led by the University of 鶹ý at Mānoa’s (HIMB) found an average adult whale must eat 142 squid daily to survive, scaling up to 416 million squid annually for the entire population of short-finned pilot whales. This data, published in the , provides a new benchmark for protecting the historically understudied marine mammals.

whales
(Photo credit: HIMB Marine Mammal Research Program)

“Pilot whales are one of the only oceanic dolphins that regularly dive to extreme depths—up to 1,000 meters—to find prey,” said William Gough, (MMRP) postdoctoral researcher and lead author of the study. “This deep-diving, high-risk foraging strategy requires a delicate balance between the energy they spend and the energy they acquire. Our study is the first step in quantifying that balance for this specific population.”

Understanding precisely how much energy the animals require is essential for understanding how to effectively manage against threats and ensure their survival.

“This detailed scientific data gives 鶹ý management agencies a critical tool to monitor how changes in the ocean—from warming waters to ship noise—might push the pilot whales past their survival limit,” said Lars Bejder, MMRP director and co-author of the study.

The deep waters surrounding the Hawaiian Islands are home to a genetically distinct population of short-finned pilot whales. These highly social, toothed whales are not migratory; they remain with their tight-knit, multi-generational families in one region for life. The population forages year-round where they pursue their preferred prey: squid.

Requirements can inform effective management

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A pod of 鶹ý short-finned pilot whales below the surface. (Photo credit: HIMB Marine Mammal Research Program)

“Deep-diving species like pilot whales are especially vulnerable to human-induced disturbances, such as noises from ships or changes in ocean temperature, which can disrupt foraging or increase their energetic costs,” said Gough. “If they use more energy than they can find, they face an energy crisis that weakens their health, hurts their ability to fight off disease, and ultimately limits their ability to reproduce and recover the population.”

Despite this inherent vulnerability, the Hawaiian pilot whale population benefits from a stable and abundant squid food source, which may better equip them to cope with environmental disturbances than populations elsewhere.

The team placed advanced Customized Animal Tracking Solutions (CATS) tags on eight short-finned pilot whales off the coast of Lānaʻi between 2021 and 2024. The tags recorded movement, depth and sound, and used 2K cameras with LED headlights to observe the whales in their lightless, 800-meter-deep hunting habitat. The researchers developed a new method to estimate minute changes in energy usage by combining data from tags with body measurements from aerial drone footage.

“Getting to be on the water and close to these animals is an absolute joy,” said Gough. “But the fact that we can see into their world, even at 800 meters and under extreme pressures [80 times that at the surface], and observe them capturing their food in complete darkness, feels unbelievable to me. It’s truly a privilege to document the lives of these elusive, deep-diving whales.”

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Hawaiian monk seals are far more ‘talkative’ than previously known /news/2025/11/12/hawaiian-monk-seals-talkative/ Wed, 12 Nov 2025 18:16:45 +0000 /news/?p=225214 The study analyzed thousands of hours of passive acoustic data and identified 25 distinct underwater vocalizations.

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two seals
Two adult Hawaiian monk seals interacting under water. (Photo credit: Krista Jaspers)

A new study by researchers from the University of 鶹ý at Mānoa’s (HIMB) has revealed that endangered Hawaiian monk seals have a hidden vocal repertoire, using a complex range of sounds to call underwater.

Previously, scientists believed monk seals had a simple repertoire, identifying only six different calls based on seals in human care. In this study, the scientists analyzed thousands of hours of passive acoustic data from the wild, they discovered 25 distinct vocalizations.

monk seal sleeping
A Hawaiian monk seal takes a snooze. (Photo credit: Fabien Vivier)

The study, published in , also found that these low–frequency calls are produced by the seals throughout the day. These vocal types were heard consistently across the Hawaiian archipelago, with calling rates highest at sites where more seals were present. This new understanding of the monk seals (Neomonachus schauinslandi) vocal repertoire opens up a new window into their acoustic behavior.

“We discovered that Hawaiian monk seals—one of the world’s most endangered marine mammals—are far more vocal underwater than previously known,” said Kirby Parnell, lead author of the study and a PhD candidate with (MMRP). “By analyzing over 4,500 hours of recordings from across the Hawaiian Archipelago, we identified more than 23,000 vocalizations representing at least 25 distinct call types.”

Monk seal vocalizations

seal swimming
An adult Hawaiian monk seal swimming. (Photo credit: Fabien Vivier)

The study, which deployed passive acoustic recorders at five key monk seal habitats from Molokaʻi to the Northwestern Hawaiian Islands, uncovered:

Expanded vocal repertoire: Researchers identified 20 previously undocumented calls.

Novel communication strategy: The research provides evidence that monk seals can combine different vocalizations together, creating “combinational calls”—a communication strategy never before reported in any pinniped (seals, sea lions and walruses) species.

A foraging call: The team discovered one novel elemental call type “the whine” produced during foraging, representing only the second known example of a seal species using vocalizations while pursuing prey.

“We were surprised by the sheer diversity and complexity of monk seal vocalizations,” said Parnell. “The discovery of combinational calls, where seals link multiple call types together, suggests a previously unknown level of complexity in pinniped acoustic communication. Finding a new call type—the Whine—associated with foraging behavior was also unexpected and suggests that monk seals may use sound not only for mating or socializing, but possibly for foraging purposes as well.”

Seal conservation in 鶹ý

These results lay the foundation for using passive acoustics to monitor monk seal populations to protect their acoustic habitats as human activity persists in Hawaiian waters. Future research will decisively link these documented vocalizations to specific Hawaiian monk seal behaviors, such as foraging, swimming, social interactions and reproduction. Next steps involve developing automated detection systems to monitor the seals’ acoustic activity more efficiently and non–invasively.

“This research provides the first comprehensive description of free–ranging Hawaiian monk seal underwater sound production, an important step toward understanding how they use sound for critical life–history events,” said Lars Bejder, director of MMRP, professor at HIMB and co–author of the study. “Because their vocalizations overlap with the same low–frequency range as many human–generated sounds (e.g. vessel noise), this work lays the foundations to evaluate how ocean noise may affect communication, reproduction, and behavior in this endangered species.”

About the team

The team included undergraduate and graduate students, and recent UH alumni, and coauthors from France and the .

“Manually annotating over 23,000 calls by hand is no small feat, and I have a team of interns to thank for helping with the analysis!” said Parnell. “This research would also not have been possible without the support of the Hawaiian Monk Seal Research Program, who deployed and retrieved the acoustic recorders in the .”

The work was supported by NOAA Fisheries via the Cooperative Ecosystem Studies Unit (CESU) award NA19NMF4720181.

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Humpback calves require 38 times more energy after birth /news/2025/10/02/humpback-calves/ Fri, 03 Oct 2025 00:08:24 +0000 /news/?p=222992 Research revealed that calves require 6–8 times the daily growth energy of an adult whale.

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mother and calf whales
A mother humpback whale with her calf on their Hawaiian breeding grounds. (Photo credit: Martin van Aswegen under NMFS Permit No: 21476)

The energy required for newborn humpback calves to grow after birth is 38 times greater than what they needed inside the womb according to research from University of 鶹ý at Mānoa (HIMB) in collaboration with Alaska Whale Foundation and other key partners. These findings were published in .

“This study addresses a key piece of the energetic puzzle in estimating the cost of being a humpback whale in the North Pacific: the cost of growth,” said Martin Van Aswegen, lead author of the study and postdoctoral researcher at HIMB’s (MMRP). “While previous research has shown that these whales must grow very large in a short period of time, the actual energetic expense of that accelerated growth remained unknown.”

Geared to grow

deploying a drone
The Alaska Whale Foundation field team on their inflatable research vessel, with pilot Martin van Aswegen landing the research drone. (Photo credit: Alexa Elliot)

Research revealed that calves require 6–8 times the daily growth energy of an adult whale, and they achieve 30% of their total lifetime growth in less than their first year of life. In fact, more than 60% of a calf’s crucial energy needs for growth occur within the first 150 days of birth.

Humpback mothers must support lactation while fasting in 鶹ý breeding grounds and then traversing back to their feeding grounds in Alaska. This exposes the mother-calf pair to significant vulnerability when ocean conditions threaten the mother’s energy stores.

The study found that a mother’s ability to produce a large, healthy calf—one more resilient to starvation and environmental stress—hinges directly on her own energy reserves. Smaller females, with lower energy reserves, face trade-offs that constrain how often they can reproduce and how much they can invest in their offspring.

“By quantifying the energetic demands of growing big and strong, we provide crucial insight into how external pressures, including climate change and human disturbance, may affect the survival and resilience of these ocean giants,” said van Aswegen.

Warning signs

whales in alaska
Humpback whales surfacing on their Southeast Alaskan feeding grounds with the drone overhead measuring their body size. (Photo credit: Fabien Vivier under NMFS permit 19703)

The study also revealed a worrying trend: mature humpback whales today are noticeably shorter than historical records, indicating a decline in body size of approximately 1–2 feet since the mid-1900s. Recent signs of humpback population stress in the region include a 76.5% drop in mother-calf sightings and an estimated 80% drop in crude birth rates in 鶹ý between 2013–2018. These declines coincided with the longest-lasting global marine heatwave, suggesting that low food availability prevented mothers from getting enough energy for the demands of nursing and calf growth. The results affected calves and juveniles, whose higher energy requirements make them highly vulnerable.

“If humpback whales are to survive threats like extreme marine heatwaves and other stressors that result from human activity, we need to understand precisely how reproductive females accumulate and allocate energy to support the exponential costs of gestation and lactation,” said Lars Bejder, director of MMRP, professor at HIMB, and senior author of the study. “This knowledge is the foundation for making the urgent conservation changes required for the population’s future.”

Drones, data

The team used drones to take high-resolution aerial photos of more than 1,500 humpback whales in 鶹ý and Southeast Alaska. They combined drone measurements with historical records and biological samples to acquire a full picture of humpback energetic needs throughout their lifespan.

“This non-invasive approach gives us a rare look at whale biology as they live, instead of relying only on historical whaling data from the 1900s,” said van Aswegen. “Our humpback whale health database, comprising over 12,000 measurements of 8,500 individual whales in the North Pacific, is being used across several projects within the Marine Mammal Research Program and abroad.”

The data can be used in conjunction with fine-scale behavior and movement data (from biologging tags), reproductive and stress hormone data (from tissue and breath samples), and tissue data derived from post-mortem events.

Partnerships

This work was made possible through MMRP, HIMB, Alaska Whale Foundation, Pacific Whale Foundation, University of Alaska Southeast, Glacier Bay National Park and Preserve, University of Alaska Fairbanks, Oregon State University, The Dolphin Institute (UH Hilo), UH Health and Stranding Lab, and HappyWhale. 鶹ý fieldwork was funded through UH Mānoa, the US Department of Defense’s Defense University Research Instrumentation Program, the Office of Naval Research, ‘Our Oceans,’ Netflix, Wildspace Productions and Freeborne Media, the Omidyar Ohana Foundation, the National Marine Sanctuary Foundation, and PacWhale Eco-Adventures, as well as members and donors of Pacific Whale Foundation. Southeast Alaska research was funded through awards from the National Geographic Society, the Lindblad Expeditions-National Geographic Funds, and the North Pacific Research Board.

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Study finds humpback whales only ones capable of bubble-net feeding /news/2025/08/19/humpback-whale-study/ Tue, 19 Aug 2025 18:27:59 +0000 /news/?p=220361 The UH research shows humpbacks use their unique pectoral flippers to achieve this maneuver.

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humback bubble net
A solitary bubble-net feeding humpback whale targeting a patch of Pacific herring in Alaska. (Photo credit: Martin van Aswegen)

In a surprising discovery, a reveals that among seven species of baleen whales, only the humpback is capable of the high-performance turns required for its signature bubble-net feeding strategy. The research, led by recent graduate Cameron Nemeth, shows humpbacks use their unique pectoral flippers to achieve this maneuver, shedding new light on the biomechanics of this iconic feeding strategy.

Nemeth just earned his bachelor of science degree in marine biology, and conducted this research as part of a larger project at UH Mānoa 鶹ý Institute of Marine Biology (HIMB) . The study focuses on solitary bubble-net feeding, a complex foraging strategy where whales release bubbles in a ring to corral prey. By combining data from drones and non-invasive suction-cup tags, Nemeth and his team were able to accurately quantify the turning performance required for this maneuver.

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Will Gough deploying a Customized Animal Tracking Solutions (CATS) tag on a humpback whale in Alaska. (Photo credit: Alaska Whale Foundation)

“The fact that humpback whales’ pectoral flippers enhance their maneuverability wasn’t the most surprising part of our study, as there have been previous studies on the morphology of these flippers,” said Nemeth. “However, it was shocking to discover that amongst thousands of turns from a variety of behavioral states, no other species of whale examined were achieving the turning performance required to create a bubble-net.”

Highly efficient pectoral flippers

The research indicates that the humpback whale’s large pectoral flippers can generate nearly half of the force needed to turn, making them highly efficient at this feeding strategy. Other whale species, even if physically capable of similar turns, would need to expend significantly more energy, likely making the strategy energetically impractical. Humpbacks’ special body shape allows them to successfully hunt smaller or scattered groups of prey.

“This is a great example of a collaborative research project that took advantage of datasets from 28 different research organizations across six countries,” said Lars Bejder, research professor at HIMB, principle investigator of MMRP, and co-author of the study. “These sorts of initiatives are able to address questions that otherwise would be very difficult to answer.”

This research is significant for 鶹ý, as humpback whales fast while in the islands, relying on the energy reserves they build up on Alaskan feeding grounds. Understanding the efficiency of their foraging techniques is crucial for assessing their overall health and energetic needs, which ultimately impacts their stay in Hawaiian waters.

Ongoing research, new Hawaiian language precedent

whale in alaska
Martin van Aswegen pilots a drone above a humpback whale in Alaska, capturing morphological data as it flukes and resumes foraging. (Photo credit: Alaska Whale Foundation)

Nemeth led this large-scale project during his final semester as an undergraduate student at UH Mānoa. He will be continuing his research with the MMRP, transitioning to a PhD program in fall 2026 to lead the lab’s ongoing humpback whale project in Maui.

In a move to increase the availability of scientific literature in the Hawaiian language, Nemeth also worked with the journal to include a Hawaiian-language abstract for the paper. He translated the abstract himself and worked with a Hawaiian language professor to edit the text, setting a precedent for future publications from the lab.

Funding for this study was provided by UH Mānoa, the Omidyar Ohana Foundation, and the Lindblad Expedition–National Geographic Fund. Equipment was provided through a Defense University Research Instrumentation award from the U.S. Department of Defense.

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New humpback whale film reveals epic journey, urgent science /news/2025/06/08/humpback-whale-film-mmrp/ Sun, 08 Jun 2025 18:15:22 +0000 /news/?p=217252 A powerful new film captures the incredible journey of humpback whales and the UH scientists working to protect them.

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Breathtaking footage of humpback whales is part of a new 12-minute video released in partnership between the (MMRP) at the University of 鶹ý at Mānoa and , in celebration of World Ocean Day (June 8). “In the Wake of Whales” follows UH scientists as they study and monitor the annual migration of humpback whales from Alaska to 鶹ý.

whales in the ocean

The video offers fascinating insights into one of nature’s most remarkable journeys—when thousands of whales travel nearly 3,000 miles to 鶹ý each year to give birth. Among the many facts shared: pregnant females do not eat during the journey, relying entirely on their fat reserves; and a single pregnancy costs a mother about 22 million calories, including 97 pounds of fetal growth per day in the final months.

“Understanding the biology and behavior of humpback whales is essential, especially now as changing ocean conditions threatens their habitats and migratory patterns,” said MMRP Director Lars Bejder. “This video helps explain how their endurance and sacrifices are truly extraordinary.”

Whale tails, whale tales

closeup of whales

The video features researchers documenting whale behaviors, collecting data and photographing the flukes of individual whales. These unique tail markings act as IDs and are uploaded to Happy Whale, a global database available to scientists and the public. With more than 10,000 whales cataloged—representing about 80% of the estimated 12,000 whales that migrate to 鶹ýMMRP’s collection is the largest in the world.

“Dolphin Quest is honored to support this research and help share it with the public,” said Dolphin Quest Co-Founder Rae Stone. “This project combines the best of science, education and conservation—and makes it accessible for everyone.”

whale underwater

MMRP operates from the on Moku o Loʻe in Աʻdz Bay and has been focused on humpback whale research for the past five years, in strategic collaboration with the . This work has helped illuminate how changing ocean conditions and increased marine heatwaves may be affecting whale health, reproduction and migration.

Dolphin Quest, founded in 1988, has locations on Oʻahu, 鶹ý and Bermuda. Its mission is “to protect marine animals and their environments through experiential learning and scientific discovery.” .

tracking whales on a screen

The video aims to inspire and educate viewers of all ages on the importance of protecting humpback whales. At the end of the film, a QR code invites viewers to support ongoing research and conservation efforts. .

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two people launching a drone into the air

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Humpback whale mother-calf health assessed using drone tech /news/2024/12/17/humpback-whale-mother-calf/ Tue, 17 Dec 2024 18:00:33 +0000 /news/?p=207786 Research revealed significant energy demands on lactating mothers and environmental stressors on calf survival and reproduction.

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mother and calf humpback whales
A mother-calf pair in the calm, shallow waters of Maui. (Photo credit: Martin van Aswegen, MMRP; NMFS permit 21476).

University of 鶹ý at Mānoa biologists used drone imagery to understand how nursing humpback whale mothers and their calves fare as they cross the Pacific Ocean. Recent declines in North Pacific humpback whale reproduction and survival of calves highlight the need to understand how mother-calf pairs expend energy across their migratory cycle. The study was .

The team used drone cameras to measure calf growth and maternal body condition days after calf birth in 鶹ý, and then compared these measurements to the body conditions of humpback females in Alaska feeding grounds, measuring pregnant and lactating (producing milk for nursing) females as well as humpback females whose reproductive status was unknown.

mother and calf humpback whales
Comparison images of the same mother-calf pair measured off Maui. (Photo credit: Martin van Aswegen, MMRP; NMFS permit 21476).

“A total of 2,410 measurements were taken from 1,659 individuals, with 405 repeat measurements from 137 lactating females used to track changes in maternal body volume over migration,” said Martin van Aswegen, (MMRP) PhD candidate and lead author of the study.

Size matters

The research shows that larger females produced larger, faster-growing calves. Over a 6-month period, lactating females decreased in body volume by an average of about 17%, whereas the calves’ body volume increased by nearly 395% and their length increased by almost 60%. In 鶹ý, humpback whale mothers lose nearly 214 pounds of blubber per day. Over a 60-day period, this is equivalent to losing roughly 50 tons of krill. Mother humpbacks in 鶹ý lost 20% of their body volume over 60 days of lactation, and the energy they used lactating surpassed the total energetic cost of their year-long pregnancies.

In Southeast Alaskan feeding grounds, lactating humpback mothers were found to have the slowest rates of weight gain compared to non-lactating females, gaining about 32 pounds each day. Comparatively, pregnant and nonpregnant females gained weight at six and two times the rate of the lactating females, respectively.

“The surprising part of this study was our ability to find the same individual mothers and calves over great distances and time periods,” said van Aswegen. “To measure the same whales over 3,000 miles apart over a period of roughly 200 days is truly remarkable and provides such valuable data for the questions we were asking.”

Birth rates decline

Studies document a 76.5% decline in mother-calf encounter rates in 鶹ý between 2013 and 2018, with birth rates declining by 80% from 2015 to 2016. In Southeast Alaskan feeding grounds, research reveals total reproductive failure in 2018, with calf survival decreasing tenfold from 2014 to 2019. These observations coincided with the longest lasting global marine heatwave, which shifted food webs and reduced availability of prey throughout the North Pacific. It is believed that humpback whales were unable to acquire sufficient food, resulting in nutritional stress and declines in reproduction.

“This work forms the basis for future studies investigating the energetic demands on humpback whales,” said Lars Bejder, MMRP director and co-author of the study. “Our humpback whale health database, comprising 11,000 measurements of 8,500 individual whales in the North Pacific, is being used across several projects within the Marine Mammal Research Program and abroad. These studies will be used to better predict the resilience of large baleen whale species in the face of threats, including disturbance, entanglement, vessel collision, and climate change.”

“This study showcases how teamwork across disciplines and institutions helps us uncover the intricate relationships between maternal health, calf growth, and environmental stressors,” said Jens Currie, MMRP PhD candidate, chief scientist at Pacific Whale Foundation and co-author of the study.

This work was done in partnership with , and other partners.

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Pregnant humpback whales’ energy needs increase when fasting during migration /news/2024/12/11/pregnant-humpback-whale/ Wed, 11 Dec 2024 21:29:33 +0000 /news/?p=207111 UH researchers uncovered the energy challenges pregnant humpback whales face during migration, especially in their final trimester.

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Aerial image of a newborn humpback whale calf off Maui. (Photo credit: Lars Bejder)

Proper intake of food is essential for pregnant humpback whales to pull off the extreme physical feat of annual migration between 鶹ý and Alaska. Researchers at the (MMRP) at University of 鶹ý at Mānoa (HIMB) revealed the energetic cost and vulnerabilities of migratory humpback mothers-to-be in a study .

Humpbacks feed in polar waters and then must fast and migrate up to 5,000 km to the tropical waters where they breed and give birth. Humpback whale mothers spend about 10 months in pregnancy, averaging about 100 days a trimester. Using a variety of new and historical records of measurement on the whales they were able to determine their findings. They found that the size of mothers directly correlated to the size of the fetus—the larger the mother the larger the fetus and the larger the growth rate.

humpback whale mother and baby
Aerial image of a young humpback whale calf off Kona, 鶹ý. (Photo credit: Martin van Aswegen)

The team determined that the energy cost of the first two thirds of the pregnancy were negligible, comprising .01–1.08% of the energy used. The majority of the energy needs came in the final third of the pregnancy, when requirements ticked up to 98.2%.

Crucial 100 days of pregnancy

“It was surprising to see how the peak of energy requirements coincided with the onset of fasting in pregnant females, ultimately highlighting how crucial those final 100 days of pregnancy are for this migratory species,” said Martin van Aswegen, PhD candidate and lead author of the study. “Females that are late in the pregnancy are therefore particularly vulnerable to disruptions in energy balance, given periods of greatest energetic stress coincide with fasting and migration to sub-tropical breeding grounds. Our study highlights a particularly vulnerable period for pregnant humpback whales. This is important, because once these whales leave their high-latitude feeding grounds, they have a finite amount of energy available to invest in their offspring over a 3–5 month fasting period, with energy requirements being even higher after calf birth.”

A 75.6% decline in the number of humpback whale mothers with calves was seen and off 鶹ý between 2013 and 2018. In Southeast Alaska, shows calf production was approximately six times lower between 2015 and 2019 compared to pre-2015 years, with mid-summer calf mortality increasing tenfold from 2014 to 2019. Studies have reported significant and prolonged shifts in the distribution of the marine food web, resulting in poor feeding conditions for humpback whales.

“This research underpins future studies on humpback whale energy demands,” said Lars Bejder, co-author of the study and director of MMRP. “Our drone-collected whale health database, developed in partnership with the Alaska Whale Foundation, includes over 11,000 measurements from 8,500 individual North Pacific whales. Its extensive temporal and spatial scale offers invaluable insights into the effects of large-scale climatic events on this iconic sentinel species. Sustaining such long-term, wide-scale studies is crucial for understanding these impacts within the context of natural variability in whale health.”

“This research underscores the value of collaboration in tackling complex questions about the lives of humpback whales,” said Jens Currie, co-author and chief scientist at Pacific Whale Foundation. “Through large-scale collaborations, we’re able to gain critical insights into the challenges migratory whales face during pregnancy to better inform conservation strategies. Together, we can address large-scale ecological challenges that no single institution could achieve alone.”

The research was done in partnership with , and others, and highlights key factors that will help inform future conservation.

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Federal advisors gain insights to oceans with 鶹ýexperts /news/2024/09/19/himb-ocean-research-advisory-panel/ Thu, 19 Sep 2024 23:43:20 +0000 /news/?p=203888 Members of the Ocean Research Advisory Panel visited HIMB in September.

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Members of ORAP convened on Oʻahu to deepen their understanding of current ocean research. (Photo credit: ORAP)

Indigenous science, coastal resilience and marine mammals were a few of the key topics covered in a visit to the University of 鶹ý at Mānoa’s (HIMB) from members of the Ocean Research Advisory Panel (ORAP) on September 3. ORAP spent time with HIMB researchers and explored the Heʻeia National Estuarine Research Reserve (NERR) to better understand current research on the state of our oceans.

ORAP’s 18 members represent the fields of marine science, technology and policy, and hold the important task of making recommendations to the White House’s Ocean Policy Committee. The visit to 鶹ý was intended to not only inform what such a national strategy should look like, but to also acquire ideas about which areas of policy the group should focus on in the cohort’s second year.

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ORAP members from left: Maria Tzortziou, Claudia Benitez-Nelson, Ana Spalding and Danielle Dickson. (Photo credit: NOAA)

The team of advisors explored topics including Indigenous science and technology through a Native Hawaiian lens; the latest approaches to coral restoration and resilience; the changing state of 鶹ý fisheries; breakthroughs in shark conservation; whales and dolphins as sentinels of our changing ocean; and biocultural practices strategies for coastal resilience.

“It was an honor to host ORAP,” said Megan Donahue, interim director of HIMB. “We shared how HIMB research informs the challenges and opportunities for ocean conservation in biocultural restoration of our coastal communities, strategies for reef resilience and coastal protection, and understanding how a diversity of marine organisms are responding and adapting to our changing oceans.”

Restoration efforts, co-stewardship

The team visited Paepae o Heʻeia, where ORAP toured the restoration efforts of the 800-year-old Hawaiian fish pond and learned about the benefits of Indigenous aquaculture systems. The panel observed research underway at NERR, which is one of the nation’s leading models of co-stewardship, including collaborative research between a university and an Indigenous community.

“The Biden Administration has issued executive memos and federal guidance about including Indigenous Knowledge in research, policy, and decision making, but many in the policy sphere still don’t know what that can look like,” said HIMB Assistant Professor and ORAP member Kawika Winter, who is director of Heʻeia NERR. “By bringing the Ocean Research Advisory Panel here, they are able to witness, experience, and learn first-hand what it can look like to effectively weave Indigenous Knowledge and university research.”

ORAP focused the first of its two-year term on advising the Ocean Policy Committee regarding the development of a National Ocean Data Strategy that improves data management, grows partnerships, and advances access and usability.

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