Who are you? Who, Who? Who, Who? Studying a cryptic marine mammal species by eDNA

By Lauren Jacobsen
HICEAS Visiting Scientist

Lauren is a Lab Associate with the Bioacoustics Research Program at Cornell University and practices veterinary medicine in western New York. She participated on a leg of HICEAS 2017 as a visiting scientist.

In the words of The Who, I am reminded of a catchy tune: “Who are you? Who, who, who, who?” As we search for the identity of a mysterious beaked whale, I just can’t help but find this to be the most fitting theme song for my expedition to the central Pacific Ocean. In mid-October, I had the exciting opportunity to participate in the Hawaiian Islands Cetacean Assessment and Ecosystem Survey (HICEAS) aboard the NOAA Ship Reuben Lasker. This was a special opportunity, not only because it was my first pelagic research cruise, but I also had the opportunity to participate in a project using environmental DNA (eDNA) to study a cryptic marine mammal species.

Will eDNA finally help us to identify a mysterious beaked whale that remains hidden from our view? Photo credit: NOAA Fisheries/Lauren Jacobsen

The HICEAS expedition is a huge collaborative effort to study dolphins, whales, seabirds, and the ecosystem of the Pacific Ocean around the main and Northwestern Hawaiian Islands. The entire HICEAS effort will span a total of 187 days aboard two NOAA Ships, the Oscar Elton Sette and the Reuben Lasker. Both ships made multiple trips, or ‘legs,’ to cover the entire study area; my 25-day involvement in HICEAS was on Leg 3 of 4 on the Lasker. My primary duty was to participate in a project to study the mysterious ‘Cross Seamount beaked whale.’ At Cross Seamount, which is located approximately 150 nautical miles south of O’ahu, unique beaked whale vocalizations have been consistently recorded, but they have yet to be associated with a known species. Compared to the more than 75 different whale, dolphin, and porpoise species that make click-type (or echolocation) noises, the clicks recorded from the animals at Cross Seamount have distinctive beaked whale characteristics. That is, they have a frequency sweep within the click and are very long in duration relative to the clicks produced by most dolphin species. The whale’s true identity has yet to be determined, but it has been affectionately referred to as the ‘Cross Seamount beaked whale’ because that is where it was initially recorded in 2005.  These clicks have also been recorded at other sites across the tropical waters of the central and western Pacific. The distribution of those recordings suggests that this is a beaked whale species in the genus Mesoplodon, although this project aims to resolve this mystery once and for all.

The location of Cross Seamount in the HICEAS study area, which is the entirety of the U.S. Exclusive Economic Zone around Hawaii (blue line). The red shading is a focus area around the main Hawaiian Islands, and the area shaded in green is the Papahānaumokuākea Marine National Monument, with darker shading showing where the Monument was expanded in 2016.

Since beaked whales are generally difficult to see (even in low sea states), and these unidentified vocalizations occur almost exclusively at night, previous efforts to pair acoustic detections with visual observations have had little success.  The HICEAS 2017 team wanted to explore other options for identifying this species, and collection of eDNA offers an opportunity to obtain genetic confirmation of the whale generating these calls. In an attempt to identify the cryptic Cross Seamount beaked whale to species, the team collected seawater samples at several depths in places where the acoustics team was hearing Cross Seamount beaked whale signals, and at several locations over Cross Seamount itself, in hopes of capturing a speck of tissue (like sloughed skin) the elusive whale left behind in the water. Seawater was collected at the surface and at a range of depths (0–1,000 meters deep) with a conductivity-temperature-depth (CTD) unit, which has sensors for making oceanographic measurements and bottles for collecting water samples throughout the water column. The CTD was also outfitted with an acoustic recorder to evaluate whether Cross Seamount beaked whales were heard during the time of the seawater collection.

Acousticians Shannon Coates (Lead for the Lasker) and Jenny Trickey show off the CTD equipped with an acoustic recorder and the seawater collection system for the Cross Seamount beaked whale eDNA study. Photo credit: NOAA Fisheries/Suzanne Yin

The HICEAS team conducted these enhanced CTDs on all three legs of the Lasker, collecting over 170 liters of seawater. The seawater samples were frozen following collection, awaiting my arrival on Leg 3. Once I was aboard, I defrosted and then filtered each of the samples through a polycarbonate filter, which is a special type of filter paper, to concentrate the DNA in the sample. Once the seawater was reduced on the filter paper, the paper was folded and spiraled into an ice cream cone-like shape and then placed into a microtube. A preservative called Longmire’s solution was added for storage and later transport back to the lab. After docking, the samples will be sent to Dr. Scott Baker and his team at the Cetacean Conservation and Genomics Lab of Oregon State University, who will investigate the genetic material in these samples. Check out the DNA Surveillance website to learn more about this process. These methods have been successful for identifying other marine and terrestrial species, so stay tuned to see what we will find! “Oh I really wanna know. Oh tell me who are you,” beaked whale?  “you, you, you, ah you?”

Lauren next to the laboratory setup of the filtering equipment and holding a filtered seawater sample secured in a microtube. Photo credit: NOAA Fisheries/Anne Simonis

“Whooo”…will we see next on HICEAS?  “Who, who, who, who?”

Lauren’s trip was funded by the Office of Naval Research and made possible by the collaborative efforts of the Pacific Islands and Southwest Fisheries Science Centers, Cornell University, and Oregon State University.

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HICEAS Hilite: Dolphins from the Outer Limits

By Paula Olson and Shannon Coates
HICEAS Lead Observer and HICEAS Lead Acoustician

One of the joys of participating in offshore surveys like the Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) of 2017 is the opportunity to see rare species. Recently there were whoops and cheers on the flying bridge of the NOAA Ship Reuben Lasker when we encountered Fraser’s dolphins! This species of dolphin, scientific name: Lagenodelphis hosei, is infrequently seen (and thus considered ‘rare’) because of its preferred deep-ocean habitat. You have to be far offshore to be in the right place to see them. And that’s where we were when we saw them on October 21.

Fraser’s dolphins seen from the NOAA Ship Reuben Lasker on October 21. Photo credit: NOAA Fisheries/Mark Cotter

Fraser’s dolphins are a bit mysterious because so little is known about them. They were a relatively late entry into the taxonomy of marine mammals. What turned out to be the skull of a Fraser’s dolphin was not studied until 1956, when it was examined by Francis Fraser and declared a new species to science. The dolphin was named in his honor. Live Fraser’s dolphins were not identified until the 1970s, when they were seen during tuna purse seine fishing in the eastern tropical Pacific. Because of their offshore distribution, they are difficult to study and information is limited for answering basic questions, including how long they live, how often they give birth, how fast they grow, and what they eat.

Generally, Fraser’s dolphins have a pantropical distribution in the Pacific, Indian, and Atlantic Oceans between the latitudes of 30° North and 30° South. Occasionally, Fraser’s dolphins can be seen nearshore where deep water is adjacent to the coast; they have been seen adjacent to the Kona coast of Hawaiʻi Island and reported nearshore in the Philippines. Fraser’s dolphins were also seen during the HICEAS of 2002 (2 sightings) and 2010 (4 sightings). October 21 was the third time that Fraser’s dolphins have been seen during HICEAS 2017. The other two groups were seen on September 29.  Each time the dolphins were in deep water far from shore, just as we would have expected. One of the groups in September was mixed together with false killer and melon-headed whales.

This map of the Hawaiian Islands shows all of the HICEAS survey effort (white lines) through November 9, 2017, with Fraser’s dolphin sightings shown as pink circles. The area shaded in green is the Papahānaumokuākea Marine National Monument, with the lighter shading showing where the Monument was expanded in 2016.

What one word describes Fraser’s dolphins? Fast!!! They’re usually seen in large groups – hundreds of individuals – and moving so quickly that they stir up frothy white water. Often they assemble in a chorus line formation, porpoising away amid lots of splashes.

Fraser’s dolphins and melon-headed whales in a mixed group on September 29. The melon-headed whale is to the far right of the group. Photo credit: NOAA Fisheries/Shannon Coates

Fraser’s dolphins are relatively easy to identify from other dolphins. They’re a stocky dolphin, with a robust body and a small beak. Their dorsal fin and flippers are noticeably smaller relative to their body size. The most distinctive characteristic is the dark gray band that extends laterally from their face to their tail stock. This band, along with a dark stripe that runs from the jaw to the flipper, creates something of a facemask – a distinctive and unique pigmentation pattern among oceanic dolphin species. In Hawaiian waters, only the adult males exhibit heavy dark bands; the patterning is much more subtle on the adult females and younger animals.

An adult male Fraser’s dolphin (left) exhibiting the diagnostic dark lateral band and jaw to flipper stripe and a subadult dolphin (right) with a muted color pattern. Note the melon-headed whale in the background. Photo credit: NOAA Fisheries/Jim Gilpatrick

Another unique characteristic of Fraser’s dolphins may lie in their vocalizations. Fraser’s dolphin vocals have been recorded during previous surveys in the Gulf of Mexico, Caribbean, and Hawaiʻi, but it was not until 2007 that their whistles were formally described and documented. Since then, there continues to be limited acoustic data available to identify their calls because the encounter rate for these animals is so low. During HICEAS 2017, we collected acoustic recordings on the three separate sightings of Fraser’s dolphins. The first two encounters were mixed species recordings, so it wasn’t until October 21 that we collected a single-species recording. The animals were producing many whistles and only a few echolocation clicks. We hope to use these whistles and clicks to help us identify the vocalizations of Fraser’s dolphins in the acoustic data from HICEAS 2017 and other surveys.

A spectrogram (or visual representation of sound) showing whistles recorded from Fraser’s dolphins.

We’ll be looking for more of these enigmatic dolphins during the final weeks of HICEAS 2017!  Keep checking the HICEAS website for updates!

All photos taken under research permit.

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HICEAS halfway: Two ships keep up the momentum surveying for whales and dolphins around Hawaiʻi

By Marie Hill and Eric Archer
HICEAS Cruise Leaders

Following up on the last progress report of the Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) of 2017, we have completed another leg of survey effort aboard the two NOAA Ships, the Oscar Elton Sette and the Rueben Lasker.  After 6-days in port in Honolulu, scientists aboard the two ships resumed surveying for cetaceans (whales and dolphins) on September 11.  The two ships tackled different parts of the study area, but both returned to Honolulu on October 10.  Given that HICEAS 2017 began on July 6 and ends on December 9, this part of the effort marked the halfway point for HICEAS!  We were excited to mark this milestone and would like to tell you more about our trip on the Sette (Cruise Leader: Marie) and the Lasker (Cruise Leader: Eric).

The Sette – Leg 3 of 3

Aboard the Sette, we started by releasing three Drifting Acoustic Spar Buoy Recorders (aka DASBRs) off of Oʻahu and Kauaʻi and then followed the planned trackline to the northwest into the Papahānaumokuākea Marine National Monument.  We surveyed 1,565 nautical miles of daytime trackline and went to the extreme west end of the exclusive economic zone (EEZ) after crossing over the International Dateline (180° longitude).

Scientists aboard the Sette celebrate as we cross over the International Dateline during Leg 3, with the first-timers wearing party hats. From left to right: Dawn Breese, Ann Allen, Jennifer Keating, Christopher Hoeffer, Andrea Bendlin, Marie Hill, Erik Norris, Carrie Sinclair, Paula Olson, Rory Driskell, Adam Ü, Greg Sanders, and Allan Ligon. Photo credit: NOAA Fisheries/Josh Fredrick

We sighted 73 cetacean groups and identified 51 of those groups to 15 species.  We saw beaked whales most often, with 25 encounters.  Because beaked whales are very elusive, and we get only brief glimpses during most encounters, we were only able to identify 9 groups to species, which included Longman’s, Blainville’s, and Cuvier’s beaked whales.  We encountered 12 other cetacean species including bottlenose dolphin, pantropical spotted dolphin, rough-toothed dolphin, spinner dolphin, striped dolphin, Risso’s dolphin, false killer whale, short-finned pilot whale, pygmy sperm whale, sperm whale, Bryde’s whale, and humpback whale.  We also saw a monk seal within the Monument, swimming offshore of Pearl and Hermes Reef.  As usual, we heard more cetacean groups than we saw, acoustically detecting 88 cetacean groups during Sette Leg 3.

Daytime survey effort (white lines) and cetacean sightings (see legend) within the Hawaiian EEZ (blue line) during HICEAS 2017 Leg 3 aboard the Oscar Elton Sette. The red shading is a focus area around the main Hawaiian Islands, and the area shaded in green is the Papahānaumokuākea Marine National Monument, with darker shading showing where the Monument was expanded in 2016.

We saw a total of 40 seabird species during Leg 3 on the Sette.  Five of the species were new for the HICEAS effort, including Mottled Petrel, Stejneger’s Petrel, Tristram’s Storm Petrel, Short-tailed Shearwater, and Pink-footed Shearwater.  At Pearl and Hermes Reef, we encountered a flock of mostly Short-tailed Shearwaters that were rafting (resting in groups) and occasionally feeding.  This was a bit of a surprise because we thought they generally made a straight shot across the middle/low latitudes when migrating from Alaska to Australia.  The fact that these birds go right through Hawaiian waters and feed and rest near the remote islands along their way reinforces the importance of the Papahānaumokuākea Marine National Monument to this species.

We took approximately 9,500 photos of cetaceans and collected 48 biopsy samples (small tissue plugs used for genetic and other analyses) from 5 species (bottlenose dolphin, rough-toothed dolphin, false killer whale, short-finned pilot whale, and humpback whale).  We also deployed satellite tags on four false killer whales.

Satellite tags are incredibly useful instruments that help us study the movements of cetaceans.  We can track individuals for weeks to months and can determine areas that are important to the animals.  In addition to the four false killer whales that we tagged during Leg 3, we deployed satellite tags on three short-finned pilot whales during Leg 2 on the Sette.  The short-finned pilot whales (triangles in the map below) were tagged off of Mauʻi and Molokaʻi and stayed north of the main Hawaiian Islands for the duration of the period their tags transmitted.  Two of the whales ventured out to the edge of the EEZ (200 nmi offshore).  Three of the four false killer whales (squares in the map below) were tagged off of Kauaʻi and Niʻihau on September 12th and 13th.  The tracks of those tagged whales overlapped for the life of the tags, indicating that they continued to travel together. One tag (purple squares) stopped transmitting on September 16th, while the second tag (green tag) transmitted until October 4th.  The third tag (yellow squares) was still transmitting on November 20th, and that false killer whale roamed far and wide.  From Kauaʻi, the whale went to the northwest into the Monument beyond French Frigate Shoals and then traveled to the northeast as far as the EEZ boundary.  It moved back and forth between the main Hawaiian Islands and the Northwestern Hawaiian Islands before heading south to the southern EEZ boundary.  The fourth false killer whale (red squares) was tagged off the west side of Oʻahu on October 8th.  The tag was still transmitting on November 20th and during that 6-week period, the whale primarily stayed off the coast of Oʻahu.

Tracks from satellite tags deployed on short-finned pilot whales (triangles) and false killer whales (squares) during HICEAS Legs 2 and 3, respectively, on the Sette. The different colors represent different tagged individuals. The white shaded area is the Papahānaumokuākea Marine National Monument, the brown shaded area is the focus area around the main Hawaiian Islands, and the outer gray line is the 200-nmi EEZ boundary.

Photo-identification and satellite tag data suggest the false killer whales we encountered on September 12th and 13th are part of the pelagic (offshore) population, whereas those encountered on October 8th are part of the main Hawaiian Islands insular population.  The biopsy samples we collected during those encounters will help us confirm the population identity of the tagged whales.

The Lasker – Leg 2 of 4

We focused on the southern portion of the study area, where we spent many days of our 2,197 nautical miles of daytime search effort with rough sea conditions and/or low cetacean sighting rates.  For a while, we developed a minor complex, wondering if we had accidentally signed up for the “HIEAS” survey!  Alas, time and persistence paid off, and we put the “C” back in HICEAS, ending up with 33 sightings of cetacean groups from at least 10 species and 109 acoustic detections of cetacean groups from at least 13 species.

Lookin’ good, Team Lasker! From left to right: Mark Cotter, Michael Force, Shannon Coates, Bernardo Alps, Andy Bankert, Eric Archer, Suzanne Yin, Brittany Hancock-Hanser, Arial Brewer, Taiki Sakai, Heather Colley, and Juan Carlos Salinas. Photo credit: NOAA Fisheries/Jennifer Cox

We had a couple of “new” species for HICEAS 2017.  Fraser’s dolphin, a relatively small and abundant oceanic dolphin, was seen (and heard) for the first time since the survey began.  Although we didn’t see it, the acoustics team detected the first minke whale “boing” of HICEAS 2017.  We collected 19 biopsy samples from four species (bottlenose and rough-toothed dolphins and false killer and sperm whales).  We also picked up four DASBRs full of data and relocated one that had drifted into shallow waters and gotten stuck!

Daytime survey effort (white lines) and cetacean sightings (see legend) made within the Hawaiian EEZ (blue line) during HICEAS 2017 Leg 2 aboard the Reuban Lasker. The red shading is a focus area around the main Hawaiian Islands, and the area shaded in green is the Papahānaumokuākea Marine National Monument, with darker shading showing where the Monument was expanded in 2016.

As for seabirds during Leg 2 of the Lasker, we recorded 3,622 individuals of at least 41 species during our strip transect effort, averaging about 125 birds per day.  Seabird diversity was high, averaging about 15 species per day, reaching a high of 22 species mid-way through the trip when we were about 150 to 170 nautical miles south and south-southwest of French Frigate Shoals.  The migration of some species was well underway during the last half of the trip, with several trans-hemispheric migrants adding to the high overall diversity.  We saw a number of rare or unusual species for Hawaiian waters–the most unexpected was a central Siberian subspecies of the Lesser Black-backed Gull that visited the ship when we were about 170 nautical miles south-southwest of South Point, Big Island. Other noteworthy sightings include Pink-footed and Flesh-footed Shearwaters, Wilson’s Storm-Petrel, Short-billed Dowitcher, and Tahiti and Herald Petrels.  We recorded 9,957 birds of at least 20 species in 56 feeding flocks, mostly over predatory fish such as tuna or mahi-mahi and often in association with flying fish.  Only one flock was seen associating with cetaceans–a widely dispersed flock of Wedge-tailed Shearwaters over a group of short-finned pilot whales.

The Sette is all done sailing for HICEAS 2017–we can’t thank the officers and crew enough for helping to make HICEAS a success!  The Lasker set sail again on October 16th for its third leg.  Stay tuned to the HICEAS website for more updates!

All photos taken under research permit.

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HICEAS seabird observers: Not just winging it

By Rachel Holton and Amanda Bradford
PIFSC Young Scientist Opportunity Intern and HICEAS Cruise Leader

While the Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) focuses on determining the size, structure, and habitat of cetacean (whale and dolphin) populations in Hawaiian waters, we have our eyes on more than just marine mammals. Specifically, we are also keeping track of seabirds in our study area. The occurrence, diversity, and abundance of seabirds are important indicators of ocean conditions, which we can use to better understand not only cetacean habitat but also ecosystem health.  How do we survey for seabirds, and what is life like for a seabird observer?  To find out, we sat down with HICEAS Seabird Observer, Dawn Breese, who kindly shared her expertise and experiences with us.

HICEAS Seabird Observer Dawn Breese is welcomed to Tern Island (French Frigate Shoals) by a line of Red-footed Boobies. Photo credit: NOAA Fisheries/Christopher Hoefer

How long have you been a bird observer?
I’ve been watching birds pretty much forever. My parents instilled a love of animals in me at a very early age. My first NOAA research cruise was as a volunteer seabird observer in 1986 on the NOAA Ship David Starr Jordan. We went from San Diego, CA, to Manzanillo, Mexico, and many of the seabirds were new to me.

Have you been on any research cruises like this before? How many? Do you enjoy them?
Yes! I love them! This is my third time participating in HICEAS (2002, 2010, and now 2017). I have also worked in the Antarctic, Alaska, the Eastern Tropical Pacific, and the California Current. I’ve probably done 30 or so seabird cruises.

Why are YOU interested in birds and why should WE (everyone else) be interested in them? How are they beneficial to the environment?
I have always been attracted to birds because of their beauty and grace. Some are outrageously colorful, and, they can fly! Their behavior is fascinating, and they are fun to watch. Being outside, be it on land or at sea, makes us feel good. Watching birds in our yard, a city park, a wilderness area, or on the water helps us gain knowledge by simply observing. Land birds are beneficial to the environment most notably by eating insects that destroy crops and invade trees. Seabird colonies provide fertilizer from their guano (poop) that enriches the marine environment all the way up the food chain.

A juvenile Gray-backed Tern flies gracefully over the open ocean. Photo credit: NOAA Fisheries/Christopher Hoefer

Has climate change affected seabirds in any way? How?
As the ocean warms, prey species and seabird distribution changes. A stark example of this was “The Blob” of warm water that affected the eastern North Pacific in the fall of 2014. By October 2014, the entire Northeast Pacific from Alaska all the way down to Mexico had temperatures that were 5-6 degrees Fahrenheit warmer than usual. Concurrent with the temperature increase, was an influx of Brown Boobies, a tropical seabird with a normal range in the eastern Pacific north to Mexico. In the fall of 2014, this species was found in California, Oregon, Washington, and British Columbia – one was even found all the way up in Sitka, Alaska! Locally, the effects of sea-level rise on hundreds of thousands of seabirds nesting in the low-lying atolls of the Papahānaumokuākea Marine National Monument could potentially be devastating. The habitat of birds that nest in burrows, such as Bonin Petrels and Wedge-tailed Shearwaters, could be flooded. Even the Laysan and Black-footed Albatrosses, which nest on the limited space available on the atolls, are vulnerable to shrinking habitat as sea levels rise.

A Wedge-tailed Shearwater chick in its burrow on Tern Island (French Frigate Shoals). Photo credit: NOAA Fisheries/Christopher Hoefer

How do you prepare for a research cruise of this size?
As mundane as it sounds, automatic bill pay and a mail hold are among the most important things I set up before going on a long cruise. I’m going to another project immediately after HICEAS, so I will be away from home from July to mid-November. We have email on the ship, so we can be in contact with family and friends while away for such a long time. In terms of packing, both projects are in warm areas so clothes and other essentials are the same for each area. The ship has laundry facilities so a week’s worth of clothes is about right. The most weight in my gear is definitely books. I like to have field guides of all types, as well as history books of the area. One huge area of preparation falls on HICEAS Co-Coordinator, Annette Henry, at the Southwest Fisheries Science Center. She takes care of sending all the computer equipment and supplies the seabird observers need.

What kind of equipment do you use on the ship?
The most important piece of equipment we use is a pair of binoculars. My personal binoculars are 10-power, the project provides handheld 20-power binoculars with an image stabilizer we call the “Little Eyes,” and mounted on hydraulic stands are four pair of 25-power “Big Eyes” that are used by the cetacean and seabird observers. We use the Big Eyes to count flocks that are far from the ship. All of our data are collected directly on a computer in real time. So, our next most important piece of equipment is our computer! Being in the elements means we have to be very conscious to protect it from sun, salt spray, and rain. We have a waterproof box the monitor, keyboard, and track pad live in, and they are connected to the main computer down in the ship’s lab. We have bird field guides handy for reference. And two must haves are sunscreen and plenty of water!

Dawn hard at work on the flying bridge of the NOAA Ship Oscar Elton Sette. Photo credit: NOAA Fisheries/Amanda Bradford

What are your responsibilities on the ship? What do you do on a daily basis on the ship?
In terms of responsibilities, I share my job with another seabird observer. We both make sure that we cover the seabird observation duties from sunrise to sunset, weather permitting. We alternate the early shift each day so no one has to always start at sunrise. My daily “commute” is up a few decks to the flying bridge, which is the deck above the bridge. The strip transect we cover daily is 300 meters from the bow to 90 degrees on either the port or starboard side, whichever has the best viewing conditions. Glare from the sun has the most impact on the side we watch. We are each “on effort” for two hours at a time, and then get a break to rest our eyes and refresh our energy! Meal times are fixed, so our shift change works out so we can each get meals.

Dawn uses the “Big Eye” binoculars to observe one last feeding flock before the sun sets. Photo credit: NOAA Fisheries/Amanda Bradford

When the cetacean observers have a sighting, we typically go “off effort” and help them locate animals and take photos and biopsy samples. Once the sighting is complete, we go back to our seabird transect duties. As the cetacean observers scan with their Big Eyes, they let us know when they see feeding flocks of seabirds. We then look through another pair of Big Eyes and count the individuals and species in each flock. Sometimes, the flock is associated with a cetacean sighting so we coordinate our time, GPS position, and flock birds to match the cetacean sighting exactly so that these data can be analyzed together. Some cetaceans and seabirds are regularly found together (for example, False Killer Whales and Wedge-tailed Shearwaters), and some are not associated at all. At the end of the day, we head down to the lab to edit and back-up the data. The sunsets at sea are the best, and if I am on the closing shift, I enjoy the sunset and watch for the green flash before heading down to do the nightly data edit.

Dawn and fellow HICEAS Seabird Observer Christopher Hoefer work on editing and backing up a day’s worth of data. Photo credit: NOAA Fisheries/Ernesto Vásquez

What did you see and learn during your time participating in HICEAS 2017?
From the NOAA Ship Oscar Elton Sette, we saw a total of 45 bird species, including 23 seabirds that breed either in the main or Northwestern Hawaiian Islands. Twenty-one were migrants that spend time feeding in Hawaiian waters, are transiting through, or, in the case of shorebirds, spending the winter. And last but not least, on our very first day, we saw one of our oddest sightings of all, 22 miles southwest of Ni`ihau, we saw a very lost Japanese Quail, a species introduced to Hawaii in the 1930s. We learned that seabirds are highly mobile creatures, and their at-sea distributions in Hawaii are not as well understood as we think. Questions will always remain about the mysterious realm of the ocean and its inhabitants!

A White (Fairy) Tern in flight over French Frigate Shoals. Photo credit: NOAA Fisheries/Christopher Hoefer

A Red-footed Booby perched on the jackstaff of the Sette – endless entertainment! Photo credit: NOAA Fisheries/Christopher Hoefer

What were some highlights or favorite moments of the survey?
Seeing one of the most amazing bird migrations on the planet, the flight of tens of thousands of Short-tailed Shearwaters headed to their breeding grounds in Australia! The spectacle of the sky being darkened with clouds of birds harkened back to the days when nature writers described wetlands with clouds of waterfowl blotting out the sun! At one point, we averaged 1.5 birds per second going through our 300 meter survey strip!

Our entertainment on the flying bridge is watching Red-footed Boobies. They perch on the jackstaff (a very tall pole on the bow of the ship) or glide just above our bow and watch with their incredible eyes for flying fish kicked up by the ship. It is a treat to watch them chase and sometimes catch these fish. They’ll also perch on the jackstaff and jockey for position to roost. It’s not unusual to have four or five of them perched at a time. They spend hours and sometimes days with us! We enjoy it, but the ship’s crew thinks otherwise as they are the ones that have to scrub the decks of guano.

Also, flying squid! For years I’ve read about flying squid being one of the principal food items for seabirds in Hawaiian waters, yet I had never seen one. This cruise changed that completely! We are used to seeing flying fish flush away from the ship, but one day they looked really different. There were “wings” in the front and the back! Looking closer, we could see the back “wings” were spread tentacles! Sheets of squid were being flushed up and chased by Red-footed Boobies! At last, the elusive flying squid! It was truly an honor to participate in HICEAS 2017. Wonderful people with exceptional skills. Thanks all around to the scientists, the birds, the marine mammals and the crew of the great Oscar Elton Sette!

A single flying fish (left third of image) in the midst of a spectacular sight – flying squid! Photo credit: NOAA Fisheries/Christopher Hoefer

Is there anything you’d like us to know about birds that we haven’t asked you about? Any fun facts?
White (Fairy) Terns have long been present in small numbers in Honolulu. If you see a pure white bird in Waikīkī, Kapiolani Park, or downtown, look carefully. There’s a good chance it’s not a pigeon, but is in fact a native Hawaiian seabird! This year, a pair was found nesting on the Honolulu Museum of Art building, and a long-scheduled painting project was halted until the young were fledged! You can see seabirds from shore at many places in the main islands. On O`ahu, Makapu`u Point, Lānai Lookout, and Ka`ena Point are good places to look. On the Big Island, if you have a spotting scope, Kēōkea Park in North Kohala is a good place to watch for rarer seabirds. It’s always a good idea to investigate your local Audubon Society. Hawai`i Audubon Society has field trips (sometimes to places closed to the general public), service projects, and talks by local bird experts.

Thank you so much for your time and insight, Dawn. We appreciate the countless hours you and your fellow HICEAS Seabird Observers (Christopher Hoefer on the Sette, Michael Force and Andy Bankert on the Reuben Lasker) have spent in observation!

What’s happening next on HICEAS: find out!

All photos taken under research permit.

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Adrift at Sea

By Ann Allen and Jennifer Keating
HICEAS Acoustician and HICEAS Lead Acoustician

What is a DASBR?

Schematic of the DASBR equipment setup.

In a previous Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) blog post (Eavesdropping on the ocean), we briefly described Drifting Acoustic Spar Buoy Recorders (DASBRs). These recorders allow us to acoustically survey the main Hawaiian Islands on a finer scale than we can with the ship’s towed array system. DASBRs are free-floating acoustic recorders that we deploy from the ship at various locations chosen based on the ocean currents. DASBRs consist of floats, line, two hydrophones, and a Soundtrap (OceanInstrumentsNZ) data logger with anchors that reach down to a depth of 150 meters (almost 500 feet). DASBRs also provide a quieter recording platform than the ship’s towed array system. When towing hydrophones behind a ship, noise from the ship itself and water flow mask sounds from some cetaceans (whales and dolphins). Because DASBRs are free floating, they do not have the same noise issue as the towed array. This means we can listen to baleen whales, in addition to the toothed whales we can detect on the towed array system. We deploy each DASBR for approximately one month at a time, but they have to be retrieved to access the data.

The HICEAS 2017 acoustic team releases a DASBR from the NOAA Ship Oscar Elton Sette. Photo credit: NOAA Fisheries/Amanda Bradford

How do you find something you left behind in the ocean?

With satellite transmitters! Each float attached to the acoustic recorders contains a small Iridium transmitter. At a pre-programmed time (usually every two hours), the transmitter looks at the satellites to determine its GPS position. It then transmits this information to the Iridium satellite network, which then sends us an email with the location. We then combine each of these locations into a track for each DASBR. This system allows us to pick up the DASBRs when they are full of data, as well as know where they were throughout their journey. The DASBR tracks can also give us a pretty good idea of what the ocean currents around Hawaiʻi look like! This whole process is not always as simple as it sounds, and electronics can be a bit finicky when you toss them into salt water. A few DASBRs stopped transmitting and went missing, and a few have managed to strand themselves in shallow water and required rescue. Overall, most DASBRs successfully completed their mission and will provide us with valuable acoustic data!

A map showing the tracks of the DASBRs we deployed during HICEAS 2017. The tracks shown in gray stopped transmitting prematurely, so we could not retrieve them. The white line shows the Hawaiian EEZ boundary (the HICEAS study area), and the gray shading is a focus area around the main Hawaiian Islands.

What can we learn from the DASBRs?

 Combining the location information with the acoustic recordings, we can learn quite a lot about cetaceans around the Hawaiian Islands. DASBRs allow us to detect species that tend to shy away from ships or that would be quiet when other sounds in their environment are noisy. The most basic information we are gathering is the WHERE and WHEN a species was present around the islands. In addition, variations in calling behavior throughout the day can give us insights into the feeding patterns of detected species. By combining the information from the two hydrophones, we can learn about the dive depths of certain species, such as beaked whales. The ultimate goal is to use the data from the DASBRs to estimate the size of some populations, starting with beaked whales. This step is important to help us better understand and protect cetacean populations in Hawaiian waters.

Once we deploy a DASBR, the only part visible is the buoy with the Iridium transmitter inside, and the orange float used as a marker and aid to recovery. Photo credit: NOAA Fisheries/Greg Sanders

Drift on over to our website for more HICEAS 2017 updates!

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The HICEAS adventures continue: Two ships join forces to search for whales and dolphins in Hawaiian waters

By Amanda Bradford and Jeff Moore
HICEAS Cruise Leaders

When we last checked in on the progress of the Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS), the first leg of HICEAS 2017 aboard the NOAA Ship Oscar Elton Sette had been completed.  A lot has happened since then!  To begin with, the Sette finished its second leg while the NOAA Ship Reuben Lasker joined the survey and accomplished its first HICEAS leg.  The Lasker traveled to the Hawaiian Islands study area from its home port in San Diego, CA, a journey that took almost 9 days and spanned approximately 2,000 nautical miles.  Here, we fill you in on our respective trips as HICEAS Cruise Leaders, Amanda on the Sette and Jeff on the Lasker.

Sette’s Second Sail

After a brief in-port following the first leg, the Sette set sail again on August 8 for a 29-day journey that ended on September 5.  Sette Leg 2 focused on the northern portion of the study area, from above the main Hawaiian Islands in the east to the far northwestern reaches above Midway and past the International Dateline.  We were pretty lucky with weather during this leg, with a majority of our 2,315 nautical miles of daytime visual effort occurring in Beaufort sea state conditions of 4 or less, which is atypical thanks to our persistent trade winds.  With the improved sea conditions, we were better able to visually detect groups of cetaceans (whales and dolphins), which is reflected in a relatively high number of cetacean sightings – 70 groups in total.  Nevertheless, we had several days with great weather when we did not see or hear any cetaceans.  On these days, we were far from land and in-between the seamounts that dot the region.  We were reminded that parts of our study area are often referred to as a “tropical desert” because the nutrient-poor waters make it difficult to support high densities of cetaceans.

Lucky 13! That is, the 13 scientists who worked tirelessly to collect data on cetaceans and seabirds during Sette’s Leg 2 of HICEAS 2017. From left to right: Rory Driskell, Ali Bayless, Erik Norris, Adam Ü, Christopher Hoefer, Amanda Bradford, Joe Fader, Allan Ligon, Amy Van Cise, Jennifer Keating, Dawn Breese, Andrea Bendlin, and Paula Olson. Photo credit: NOAA Fisheries/Hung “Doc” Tran

The 70 sightings made by the cetacean observers included at least 13 species, ranging from the small spinner dolphin to the large Bryde’s whale.  The most frequently sighted species was the striped dolphin, seen a whopping 14 times, followed by the short-finned pilot whale, which was seen 10 times.  Most other species were seen only 1-2 times.  Our most exciting sightings were of beaked whales, which are elusive and difficult to detect.  First, we had 2 sightings of Longman’s beaked whales, including a group with almost 100 animals, a rare and poorly-known species.  Then, we had a small group of Blainville’s beaked whales approach the ship very closely multiple times during an extended period at the surface, seemingly as curious about us as we were about them.  We took almost 10,000 photos during these cetacean sightings, from both the ship and seven launches of the small boat.  We collected 33 biopsy samples (small tissue plugs used for genetic and other analyses) from four species (spotted, rough-toothed, and bottlenose dolphins and short-finned pilot whales) and deployed satellite tags on three short-finned pilot whales to study the movements of these individuals.

Daytime survey effort (white lines) and cetacean sightings (see legend) made within the Hawaiian EEZ (blue line) during HICEAS 2017 Leg 2 aboard the Oscar Elton Sette. The red shading is a focus area around the main Hawaiian Islands, and the area shaded in green is the Papahānaumokuākea Marine National Monument, with slightly darker shading showing where the Monument was expanded in 2016.

The acoustics team was also busy, detecting 127 vocal groups of cetaceans.  They also kept our Drifting Autonomous Spar Buoy Recorder, aka DASBR, project going.  During Sette Leg 2, we released seven DASBRs to listen for vocalizing cetaceans in our absence and picked up three others from Leg 1 that were full of data!  We also deployed 43 sonobuoys that allow us to detect vocalizing baleen whales that may be in the area.  The seabird observers recorded thousands of bird sightings from at least 35 species, with the Herald/Henderson’s Petrel, Flesh-footed Shearwater, Sooty Shearwater, Parasitic Jaeger, and Pacific Golden Plover all new species for HICEAS 2017.  The Pacific Golden Plovers were returning to their wintering grounds in Hawai’i after spending a summer in Alaska.  Named Kōlea in Hawaiian, these shorebirds are known to return to the exact same location year after year, even the same yard!  Although seabirds tell us a lot about ocean productivity in our study area, we also conducted 35 CTD (Conductivity-Temperature-Depth) casts to learn more about the physical properties of the waters we surveyed.  Finally, while we rarely saw the species we were targeting for health assessment using an Unmanned Aircraft System (UAS aka drone) when the winds were light, we were able to make 6 hexacopter flights over short-finned pilot whales.

Lasker’s Leading Leg

The Lasker left San Diego on August 17 bound for the HICEAS study area.  To get there as quickly as possible, the cetacean observers worked in what we call ‘passing mode,’ when the ship does not leave the trackline to investigate sightings.  As the days passed, we could tell we were approaching the tropics as air and water temperatures got higher, sightings of tropical seabirds increased, and the trade winds made their presence known.  We arrived in the study area in the pre-dawn hours of August 26, conducting our effort from that day forward in ‘closing mode,’ when the ship “closes” on a sighting to have better looks and more time to obtain species identification, group size estimates, and other information.  Our effort focused on the area south and east of the main Hawaiian Islands, where we surveyed until September 5, ending our 20-day leg.  All told, we completed 1,844 nautical miles of daytime visual effort, with 696 nautical miles in Hawaiian waters.  We sighted 53 cetacean groups – 34 of them were in the HICEAS study area.

Fabulous 14! The ace scientific complement during Lasker’s Leg 1 of HICEAS 2017 (sending birthday greetings to two members of Team Sette). From left to right: Mark Cotter, Heather Colley, Andy Bankert, Jenny Trickey, Jim Gilpatrick, Shannon Coates, Jeff Moore, Suzanne Yin, Seth Sykora-Bodie, Megan Slack, Juan Carlos Salinas Vargas, Marie Hill, Bernardo Alps, and Michael Force. Photo credit: NOAA Fisheries/PJ Klavon

The 34 sightings of cetaceans in the study area were from 10 identified species – all species seen during Sette Leg 2, with the exception of the pygmy killer whale.  We collected two biopsy samples, one from a spotted dolphin and another from a rough-toothed dolphin.  Like the Sette, we saw Longman’s beaked whales (although three times!), which was a highlight for us also.  However, our other exciting cetacean detections occurred acoustically.  One night, at about 10 pm, a few of us were gathered in the acoustics lab.  The hydrophone array was still in the water recording, but no one was actively monitoring it, as is usually the case once the sun sets and the observers go off effort.  At just the right moment, faint calls appeared on the computer monitor, and we decided to put the headphones on to listen. Good thing, because killer whales were in the area and gave us quite a performance.  We were treated to a vocal repertoire that sounded somewhat Shamu-like and lasted for over an hour.  If only there had been light left outside to see the animals because it would have been a spectacular encounter.

Daytime survey effort (white lines) and cetacean sightings (see legend) made during HICEAS 2017 Leg 1 aboard the Reuben Lasker, including its transit to the Hawaiian EEZ (blue line). The red shading is a focus area around the main Hawaiian Islands, and the area shaded in green is the Papahānaumokuākea Marine National Monument.

The most memorable moment of Lasker Leg 1 took place when the acoustic team began detecting the Cross Seamount beaked whale an hour before dusk.  This beaked whale, first heard at Cross Seamount, is known only from acoustic recordings and sounds unlike any known beaked whale species with acoustic recordings.  With the long, upswept vocalization clicks, there was no doubt that we had found this mystery beaked whale.  We acoustically tracked the animal(s) for over an hour hoping to at long last visually identify the species making these clicks.  As the sun went down, we were losing hope.  Darkness set in, but right before it did, our amazing Lead Cetacean Observer, Suzanne Yin, caught a glimpse of a cetacean that might have been our unknown whale.  Unable to get a good look and confirm the species, we at least got one step closer to identifying the mysterious Cross Seamount beaked whale!  Overall for acoustics, there were 106 detections of cetacean groups during Lasker Leg 1, and we picked up 2 DASBRs.  Finally, the seabird observers encountered 4,916 birds (of at least 15 species) in 28 feeding flocks and recorded 1,830 birds (of at least 42 species) during their strip-transect survey effort.

The Sette Leg 2 and Lasker Leg 1 teams appreciated the help of their visiting scientists, Duke University graduate students Joe Fader (Sette) and Seth Sykora-Bodie (Lasker), who wrote a great blog post about their experiences.  The Sette and Lasker went back to sea for their respective third and second legs on September 11.  Keep checking the HICEAS website for more information on what happened next!

All photos taken under research permit.

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