Research News

New Function for Bubbles Observed in Hawaiian Humpback Breeding Grounds

November 28, 2022 by Whale Trust Maui

Read Full Paper: Female Humpback Whale Positions Genital-Mammary Area to Intercept Bubbles Emitted by Males on the Hawaiian Breeding Grounds

Aquatic Mammals 2022, 48(6), 617-620, DOI 10.1578/AM.48.6.2022.617

Humpback whales are well known for their use of bubbles. One of their most widely documented uses occurs in a feeding context where either an individual or group of humpbacks utilize a variety of bubble-based tactics to net, trap, and herd their prey.

Flip Nicklin/Minden Pictures. NMFS Permit #19225.

We report a different use of bubbles by humpbacks in the Hawaiian breeding grounds on multiple occasions between 2000 and 2003 in the Au’au Channel off West Maui, Hawaii. Our research team at Whale Trust filmed a 14-minute interaction between multiple males and one female in which the males circled the female and produced bubbles directed toward the female’s swollen genital region. The female appeared to tolerate and possibly aid in the reception of these bubbles. We have observed similar scenarios on multiple other occasions as well.

These observations are intriguing and reveal a new dimension to male-female interactions on the breeding grounds. There are two primary contexts within which to consider this behavior:

(1) To maximize mating opportunities – Mating/Estrus Female

In the scenario that the female was present to mate and in estrus (a recurring state of sexual receptivity and fertility in many female mammals) this could explain her receptiveness of the males and the males’ attention toward the female.
In this case, we could speculate that this interaction may serve a sexual purpose such as helping stimulate the female prior to intercourse or assisting in the release of chemical cues that could signal to the male her reproductive status and readiness to mate.

(2) To ensure successful birth and calf development – Late Pregnant Female

In the scenario that the female present was a late pregnant female and about to give birth, this could explain her extended girth, swollen genitals, and even the presence of multiple males around a birthing female.
In this case, we could speculate that the bubbles could stimulate the release of hormones, such as oxytocin, known to be vital in the birthing process.
The pressing question is, if this is the correct case, why are males involved and not females? What is in it for the males?

While interpretation of the use of bubbles in our recording and their exact meaning remains speculative, it does show the complex and wide array of bubble use in humpback whales. Future research aimed at understanding the hormonal state of male and female humpbacks within different social groups and situations on breeding grounds should provide the insight needed to determine the correct context for the behavior patterns described here.

HUMPACS SURVEY RESULTS PUBLISHED

July 1, 2019 by Whale Trust Maui

Autonomous (Robotic) Wave Glider Mission from Hawaii to Mexico Detects Humpback Whale Calls in Tropical Mid-Ocean and Questions Definition of Winter Breeding Assemblies

Current NMFS humpback whale management policies assume Mexico and Hawaii winter assemblies are distinct with separate status and management warranted

BIG ISLAND, HAWAII – Jupiter Research Foundation and Whale Trust are pleased to announce the publication of the results of the first leg of their autonomous Wave Glider HUMPACS (Humpback Pacific Survey) acoustic survey in The Journal of the Acoustical Society of America – Express Letters. During a 100-day nearly 7,000 km (3,800 nm) round trip survey on a line between Hawaii and Mexico, during winter breeding season of 2018, humpback whale calls were heard in mid-ocean basin, halfway between the known near-shore assemblies.

“They’re not ‘supposed’ to be there,” says Dr. Jim Darling, Whale Trust biologist and project partner. Humpbacks are known to assemble in specific near-shore, relatively shallow, breeding grounds in Mexico and Hawaii. “But then no one has looked in these more remote, offshore areas either.”

Mission control was from Puako, Hawaii where Beth Goodwin, Jupiter Research Foundation VP and HUMPACS Project Manager, and her team were in daily communication with the Wave Glider: monitoring status, downloading surface and underwater photographs, downloading short samples of recordings via satellite, and making course alterations if needed.

From January 16 to April 25, 2018, the Wave Glider, named Europa (after one of Jupiter’s moons), performed a 6,965.5 km, 100-day (RT) continual acoustic survey from Hawaii towards Mexico circa 20° N. The survey resulted in 2,272 hours of recordings and included over 4,000 cetacean calls. Of these calls, 2,048 were identified as humpback whale calls.

The humpback calls were recorded up to 2,184 km (1179 nm) offshore spanning 30 days between January 20, when the Wave Glider left Hawaii, to February 23, 2018. On many days, multiple humpback call detections were recorded (up to 377 calls over 23 hours of a day). Actual numbers of whales cannot be determined, as one whale can make many calls.

“This was risky, we had no idea if humpbacks were even out there,” says Goodwin. “And then, even if they were, there were needle-in-haystack odds of intersecting them considering the size of the Wave Glider and the size of the ocean.”

Possible explanations, suggests Darling, include an undocumented migration route to Hawaii, a separate (from Hawaii and Mexico) offshore assembly of humpback whales, or travel between Mexico and Hawaii assemblies within the same season. At the very least, these results indicate an extension of winter distribution and habitat of humpbacks. It could also be that these offshore whales have not been included in current population estimates.

Since 2016, the model used by the U.S. National Marine Fisheries Service (NMFS) to manage humpback whale populations has treated the Mexico and Hawaii winter assemblies of humpback whales as distinct populations. As such, these populations have different status under the U.S. Endangered Species Act (ESA): Mexico humpback whales are considered threatened while Hawaii humpback whales have been delisted; that is, the Hawaii population has no protection under the ESA.

This assessment is further complicated by longstanding research showing shared song between the breeding assemblies and an interchange of photo-identified individual whales between these two winter breeding grounds.

Our findings question the independence of Mexico and Hawaii humpback whale populations and illustrate the huge potential for the use of autonomous vehicles in the study of whales across remote locations of the ocean.

“We feel certain our results will encourage more research, affect how humpback and other whales are monitored, and help with management,” says Goodwin.

The paper is online: https://doi.org/10.1121/1.5111970

BACKGROUND

Wave Glider

The Wave Glider (produced by Liquid Robotics, a Boeing Company) consists of a surfboard-sized surface platform (the float) tethered by an umbilical cable to a submerged glider (the sub) 8 m (26 ft.) below the surface. The float includes a command and control unit, three solar panels, an instrument package, surface and underwater cameras and communications systems. The sub is the propulsion unit, which transforms vertical wave movement into forward motion (https://www.liquid-robotics.com/wave-glider/how-it-works/). Time-lapse series of images from the two Europa cameras, surface and underwater, are accessible on the JRF blog:
http://jupiterfoundation.org/current/2018/5/22/f2l6bevguh177l21x42gi20pegicbv

About Jupiter Research Foundation

The Jupiter Research Foundation is a 501(c)(3) non-profit scientific research organization. Established in 2003, the Foundation is dedicated to conducting innovative scientific research and finding technological solutions to problems which are outside of mainstream science and technology. Our findings are shared with the public and academic community in hopes of better monitoring and understanding the natural world. Visit https://jupiterfoundation.org/ to learn more.

About Whale Trust

Whale Trust is a Maui-based 501(c)(3) non-profit organization whose mission is to promote, support and conduct scientific research on whales and the marine environment and broadly communicate the findings to the public. Whale Trust research programs focus on behavior, communication and social organization of whales. For more information, visit https://whaletrust.org/.

Researchers Observe Sailing Whale off West Maui Coast

February 9, 2019 by Whale Trust Maui

(Maui) Whale Trust’s research team captured this footage on February 7th near Olowalu, showing a mom with her head down and pectoral fins out while her young calf circles around. The encounter marks the third time this season that the team has identified the same female humpback whale displaying the rarely observed behavior known as “sailing.” The behavior, in which a whale lifts its tail clear of the water for long periods of time, is common in right whale populations but less common in humpbacks. When humpback whales, especially mothers, in Maui are observed sailing it is not uncommon to observe one individual repeating the behavior pattern within and between seasons. The purpose of sailing is unknown but one idea is that it may help to regulate body temperature.

Haley Robb, a Whale Trust research intern, reports, “The cow held her fluke in the air for 7-10 minutes before floating up, backward, and then resting at the surface for approximately 5 minutes. She then repeated the sailing behavior. We stayed with the cow and calf for two hours and were unable to determine if the calf nursed when the cow was holding this position. During our time with the group, there were two occasions when the cow and calf breached. It was noted that for a least one of the occasions there were other whales within 300 yards of the cow and calf.”

Whale Trust’s research programs focus on exploring the natural communication, behavior patterns, and social organization of whales. Its founders are passionate scientists and explorers who believe that science—the quest for answers to the most intriguing questions about our natural world—lies at the heart of environmental education and conservation. Results from Whale Trust’s field research are the basis for a broad program of outreach and education that involve the public, educators, and a new generation of researchers. As part of Whale Trust’s outreach, the organization hosts Whale Tales, an annual 4-day educational event in West Maui featuring presentations by world-renowned scientists, conservationists, and photographers. The 13th Annual Whale Tales is scheduled for February 15-18, 2019. Learn more at whaletrust.org,

Video: Ralph Pace, Whale Trust. NMFS Permit #19225.

Photo: Ralph Pace/Minden Pictures, Whale Trust. NMFS Permit #19225.

Whale Trust 2017-2018 Research Season Recap

June 11, 2018 by Dayna Garland

The Whale Trust research team spent 87 days on the water this season:

Identifying 116 whales, with 12 confirmed matches to our catalog from previous years.
Collecting 8 tissue samples for hormone analysis to help understand the mating and birthing cycle on the breeding grounds.
Recording 20 different singers during three periods of the season – January, February, and March to study how the song changes over the season.
Capturing hundreds of photographs and hours of video footage for analysis of natural behavior. Highlights of the season included a nursing calf with its mother and a single female joined by two competitive males.

STORIES FROM THE FIELD

PC: Ralph Pace. Photo obtained under NMFS permit #19225.

So Great to See You Again!

Meagan Jones, PhD and Haley Robb

Our team was thrilled to have several matches this season including:

A match with a female documented in the Alaska humpbacks catalog and last seen in 2004.
A match to a humpback documented in the Gulf of Alaska in 2006.
A match to our Whale Trust catalog of a female whale last seen in 2003 when she was paired with a male. This year, she was spotted as part of a competitive group!

PC: Flip Nicklin/Minden Pictures. Photo obtained under NMFS permit #987.

Sing to Me

Jim Darling, PhD

During the winter a total of 20 different singers were recorded. The season was divided into three periods; early (January), mid (February) and late (March) with 6, 7, and 7 singers recorded in each period respectively. Our objective is to determine if there is more similarity of song within each period than between the periods. This study compares songs sung at different times in one location to determine if the song provides an acoustic identity to whales that are present at any one time.

Pregnant? Mating?

Jim Darling and Meagan Jones

We collected tissue samples from 8 female humpbacks this season. We are interested in determining if the adult females paired with males were pregnant (and about to give birth) or not pregnant and about to mate. Pregnancy can be determined by analysis of the hormone levels in the blubber portion of the sample. On the one hand we will be surprised if these females are pregnant – while on the other hand, if they are not pregnant where are the mothers-to-be?

A Moment in Time

Flip Nicklin, Jason Sturgis, and Ralph Pace

A highlight of the season was a rarely observed interaction between a cow and calf. Both animals were very relaxed and the mother kept bringing the calf near the boat. While in the water documenting their behavior, we noticed the calf opening its mouth – not something that you see all the time. The calf then moved from the back of the mother up to her head and started opening and closing its mouth right beside her head. Then the mother completely stopped and the calf went to the nipple of the cow and began to nurse. You could see the calf tucked in under its mother and white milk seeping out from the sides of its mouth. It was magnificent to witness this first hand. Not only was it incredible to see nursing from a very comfortable cow and calf, it was remarkable to see the calf opening its mouth right in front of its mother. There are many possible interpretations of this behavior and we are left with more questions than answers.

Emerging Scientists

After completing her Bachelor of Science in marine biology last year, Haley Robb joined the Whale Trust Research Team as an intern throughout the 2017-18 research season. It has been incredible to work with Haley and watch as she pursued her passion. She helped capture ID photos and documentation through extensive field notes. Haley shares, “From as long as I can remember I have been fascinated with marine life. As middle school student, I was able to attend Whale Quest (Whale Tales), a wonderful event put on by Whale Trust serving to bridge the gap between research and local communities. Whale Trust has been an extremely influential part of my decision to become a marine biologist. Through their educational programs, many opportunities were created for me.” Haley has spent the off-season working on data analysis and ID matching and plans to join the team again during 2018-19 season!

Solitary Female

Flip Nicklin, Jason Sturgis, and Ralph Pace

We were out on the water in February and came across a single whale about 2 miles off Olawalu. We could see that the animal wasn’t too deep so we decided to slip over the side and get some footage and shoot some stills. After diving under the animal, we could see that it was a female. It is a rarity to see a female all by herself. We spent the better part of an hour with her when she was joined by a male with white pecs. There were some interesting social sounds being vocalized but it was impossible to tell who they were coming from. The white pec male had not been with her long when another male came in and displaced the white pec escort. Things then escalated into a mini-active group but the female was quite content to stay put and let the action revolve around her. It was wonderful to see that whole sequence from the beginning — not something that we get to witness very often.

PC: Flip Nicklin/Minden Pictures. Photo obtained under NMFS permit #19225.

Citizen Science Meets Research Photography

Meagan Jones, PhD and Cathy Maxwell, PhD (Whale Trust Board Member)

Happywhale tracks individual whales throughout our world’s oceans and believes that whale watching guides, naturalists, and passengers are vital to our understanding of whales. Scientists can only be in one place at one time; by harnessing the power of millions of whale watching enthusiasts, we can expand our scientific knowledge exponentially. Whale Trust is supporting the educational outreach of (Link) Happywhale by contributing to the online catalog. We love seeing matches come through and Whale Trust has now contributed more than half of the whale IDs in the catalog! Learn more and submit your photos next season at Happywhale.org!

Ed Lyman / HIHWNMS / NOAA Fisheries Permit #782-1719 (Original image has been altered to include Wave Glider)

Listen!

Jim Darling, PhD and Beth Goodwin (Jupiter Foundation)

Whale Trust is pleased to be a partner on Jupiter Foundation’s HUMPACS project. An unmanned wave glider recently returned from an unprecedented 3-month mission to listen for humpback whales in the deep ocean basin between Hawaii and Mexico. The mission provided more than 2000 hours of recordings for analysis. Stay tuned for results and in the meantime, learn more about the wave glider on the HUMPACS page.

At a Whale’s Pace

December 29, 2016 by Whale Trust Maui

With whales spending 90% of their time underwater, one of the biggest challenges for a whale behaviorist is to actually see them! Thanks to your generous support, we are now on the cusp of new discoveries into the underwater social lives of whales on the breeding grounds.

The warm, clear waters of Hawai’i make this one of the best places in the world to study whale behavior. It is one of the few places we can actually observe whales underwater, on the surface and from the air. Many research breakthroughs have come from of this unique natural observatory. However, since whales move faster than a person can swim, our understanding of their behavior is often based on pieced together, fleeting glimpses. Key questions remain – some as fundamental as when and where mating occurs.

To help answer these questions, this winter we will embark on a new project designed to bring together traditional research techniques (individual identification, sound recording and biopsy sampling) with new technologies (unmanned aerial vehicles and a mounted camera jib).

NEW TECHNOLOGY USHERS IN A NEW ERA OF WHALE RESEARCH

With the new accessibility of drones, unprecedented and high-quality aerial views of whale behaviors and interactions are now cost-effective and possible. Our new underwater camera jib, mounted under the boat, allows us to film whales moving at their natural speed. Together, these new tools promise to give us a new window into fast-moving social groups.

Instead of seeing whale behavior in brief moments, we can now capture longer sequences of whale behavior as well as interactions between individual whales. This is a tremendous leap forward—much like the first underwater photographs of whales in the 1970s and 80s, which significantly altered the world’s perception of these animals.

Our challenge is to compile as complete a picture as possible of the behavior patterns occurring in social groups on the breeding grounds. Capturing this in real time will provide a new key to understanding the nature of whales. It also will help set a new foundation of knowledge into humpback behavior for future management and conservation programs.

From the 2016 Whale Trust Maui Newsletter (November 2016). Click here to read more!

2017: A Critical Year for Humpbacks in Hawaii

October 5, 2016 by Dayna Garland

Next year (2017) may go down as one of the most critical years for humpback whale research in Hawaii in the last fifty years. For the first time since 1966 when whaling was deemed illegal in the North Pacific, humpbacks will no longer be considered an endangered species trying to come back from the brink of extinction. While there are many reasons to celebrate this recovery, on the heels of this landmark decision was one of the most abnormal winters on record for humpback whales across the Pacific Ocean.

The decision to delist humpbacks has left many researchers with mixed feelings on how to respond. On the one hand, there is no question that the number of humpbacks has increased substantially in most areas of the world since whaling stopped; and humpbacks will still be protected under the Marine Mammal Protection Act in the U.S. On the other hand, the decision does not reflect or indicate that we actually understand the biological, ecological, and social requirements for these populations to continue to recover and thrive in a changing world. Indeed, we are venturing into unchartered territory with no clear grasp on how the complex and changing landscape of their environment will impact populations going forward. All of which is vital to developing and implementing any kind of meaningful conservation and management program.

The winter of 2016, in terms of the sheer number of whales and the behavior of whales on breeding grounds across the North Pacific, was undeniably one of the strangest on record. There were noticeably fewer whales, changes in migration patterns (the breeding season started later and ended earlier), dramatic changes in behavior (less surface activity associated with mating strategies, longer downtimes), and fewer mothers and calves observed. In Hawaii, we speculated that far fewer females had shown up than usual. If indeed this is true, where were they? Did they not migrate as far south as usual? Did they stay on or around the feeding grounds? If so, how has will this affect reproduction going forward?

We have no idea what happened in 2016 or why. One aberrant season does not warrant a crisis. However, what it did emphasize was an almost shocking lack of knowledge about these animals, and the stark recognition of a large gap in current research efforts. Systematic monitoring on the abundance of whales on breeding grounds has become nearly obsolete over the past ten years. Without collecting this kind of consistent baseline data it is impossible to determine just how different from “normal” 2016 really was.

As such, Whale Trust is expanding our core research program to include a systematic monitoring component that will contribute to validating and investigating large-scale changes in abundance and behavior. Our commitment to research on social organization, behavior and communication has not changed – but if nothing else, 2016 told us we need to do more. The change in the endangered species designation of humpbacks makes this responsibility even more compelling.

So why is 2017 so important? It marks the first season of the official ‘recovery’ of the humpback population that ironically coincides with the biggest mystery on humpback status since whaling stopped. Consequently, monitoring breeding populations will be even more vital this coming season than in previous ones. Either the season will be similar to 2016 in which case some critical questions as to the health of the population will arise, or, it will be back to “normal” in which case we will be left wondering what happened – with lingering questions about how sensitive whales are to minor changes in water temperature and what this means in the context of global warming.