HICEAS Hilite: Close encounters of the rare kind, the Longman’s beaked whale aka Indopacetus

By Suzanne Yin and Andrea Bendlin
HICEAS Lead Cetacean Observers

Disclaimer: Biologists, like other groups of people, have a lingo that we use in our daily work.  Just like “a slice to go” means a piece of pizza to take away to eat, and a “pick-6” is an interception and touchdown in football, biologists use terms meant to make our communication as clear and efficient as possible.  All animals have a scientific name in Latin and a common name, whether it is Homo sapiens (human), Phoebastria nigripes (Black-footed Albatross), or Gorilla gorilla (no explanation necessary).  Common names can sometimes be confusing.  For instance, the short-beaked common dolphin (Delphinus delphis) and the long-beaked common dolphin (Delphinus capensis) are indeed common in some locations.  But Delphinus are not so common in other parts of the world (they’re not even found in Hawaiian waters), where another species of dolphin may be the ‘common’ dolphin.  In Hawaii, the most commonly seen dolphin is the spinner dolphin (Stenella longirostris).  Additionally, we are an international community of scientists, and a common name in English may not directly translate in another language.  Thus, we often use scientific names, even in our casual everyday conversation, so that we can speak about animals using a shared language.

Indopacetus?!  That was my question to the other Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) observers after I raced up to the flying bridge of the NOAA Ship Reuben Lasker.  The visual team had called on the VHF radio, informing the acoustics team and everyone who had a radio that they had a sighting.  I wasn’t on watch, but I climbed the 31 stairs from my room up to the flying bridge to find out more.  They described what they had seen through the 25-powered binoculars that we call “big eyes”—quite a few animals, all together, puffy blows, light in color, big size even though they were still distant.  And so I said it again, “Indopacetus?!”  A fellow observer nodded his head and said, “I think so.”  And I smiled.  You could feel a frisson of excitement from everyone on the flying bridge.  Most of the scientific party on the Lasker had not seen this species before.  This was going to be good!

The setting sun highlights the puffy blows characteristic of Indopacetus. Photo credit: NOAA Fisheries/Amanda Bradford

Indopacetus pacificus, or the Longman’s beaked whale, is one of the most rarely seen species of beaked whale.  In fact, we have seasoned colleagues who have sailed in tropical waters for years and have never seen them.  If you ask a cetacean observer working in Hawaii what species is at the top of their “to see” list, for most, it’s Indopacetus.  For those of us who have seen them, you can feel the sense of awe (and envy?!) when someone asks, “You’ve seen Indopacetus?”

Until about 20 years ago, we only really knew about these toothed whales from two skulls, one from Somalia and one from Australia.  They were a mystery species, which is surprising because they aren’t small in size or particularly cryptic once you find them (which of course isn’t easy)!  For years, scientists had reported sightings of a tropical bottlenose whale (a toothed whale with a bulbous melon, which is sort of like having a big forehead).  But, it wasn’t until 2003 when scientist Merel Dalebout and colleagues, using genetic samples from stranded animals, determined that the tropical bottlenose whale and Indopacetus were the same animal.

The face of an Indopactus, a rare and exciting sight! Photo credit: NOAA Fisheries/Paula Olson

Indopacetus can be found in large groups, from a handful to upwards of 100 individuals.  They are large in size (up to 20 feet) and have a visible blow.  They can be tan to light brown in color and have a very distinct rostrum (beak).  They can often be found associating with short-finned pilot whales (Globicephala macrorhynchus) and several species of smaller dolphin.  In one of our recent HICEAS sightings, they were mixed with a large group of short-finned pilot whales.  From stranding and sighting data, we do know that they seem to have a vast distribution, inhabiting tropical waters in the Pacific and Indian Oceans.  Yet, we know next to nothing about their diet, diving capabilities, or reproductive behavior.  Are they more active during the day or night?   Or are they a crepuscular species that is more active at twilight?

This Indopacetus surfaces quickly and moves through the water even faster, giving us few chances to uncover their secrets. Photo credit: NOAA Fisheries/Adam Ü

So far during HICEAS, both the Lasker and the NOAA Ship Oscar Elton Sette have each had a few sightings and acoustic detections of Indopacetus in various parts of the study area, with some of the sightings and detections over a thousand nautical miles away from each other.  During the last HICEAS in 2010, there were only three Indopacetus sightings, but one of them involved a large group of approximately 100 animals in the northwestern reaches of the study areaWe were all hoping we might have a sighting like that again this year, and sure enough, we sighted from the Sette a similar-sized group of animals just 150 nautical miles from where they were seen in 2010.  Was it the same group?  Unfortunately, we were unable to collect genetic samples in 2010 or 2017, so we may never know.  Have we found an Indopacetus hot spot?  Perhaps.  Only further research will tell.  We can only hope the remainder of HICEAS will bring more sightings.  There is one thing we do know for sure–for those of us lucky enough to have an Indopacetus sighting as part of our HICEAS 2017 experience, it is something we will always remember!

This map of the Hawaiian Islands shows all of the HICEAS survey effort (white lines) through September 5, 2017, with Indopacetus sightings shown as orange squares. The area shaded in green is the Papahānaumokuākea Marine National Monument, with slightly lighter shading showing where the Monument was expanded in 2016.

What else will the remainder of HICEAS bring?  Find out on the HICEAS website!

All photos taken under research permit.

A day in the life of the East Island Exiles

How we stayed sane on the smallest island field camp in the Northwestern Hawaiian Islands

by Marylou Staman

Imagine this: You wake up on a cot, under a canvas tent, and blink your eyes, wondering where you are. As you remove your ear plugs, the dull sound of birds nesting under your tent becomes a cacophony of screams, honks, and wails, and the afternoon sunlight streaming through gaps in the tent walls burns your eyes. It’s hot, you’re exhausted, and yet you smile, because you finally remember that you’re on East Island, and in the middle of the greatest adventure of your life.

Monk seals and turtles often basked together on East Island (Photo: NOAA Fisheries/Jan Willem Staman).

East Island, our home for the majority of our summer up at French Frigate Shoals in the remote Northwestern Hawaiian Islands, is only about 2000 feet long and 400 feet wide. Because of its size and our initial impressions from satellite images, we originally dubbed our future home a “sand bar,” devoid of life. But upon closer inspection we found the island to be rich with birds, Hawaiian monk seals, vegetation, and of course, sea turtles. Even the beautiful turquoise water surrounding the island, our front yard, provided us with daily sightings of schooling trevally, foraging eagle rays, and huge tiger sharks, patrolling the shallow lagoon waters for disoriented albatross fledglings that landed on the water while learning how to fly. With the gorgeous scenery and wildlife keeping us company every day, it was easy to fall in love with our tiny island home.

Marylou, Jan Willem, and Alex (L-R) pose on their camp “front porch” on East Island (Photo: NOAA Fisheries).

But what brought us to East Island? My husband, Jan Willem Staman, and I, along with our colleague Alex Reininger, made up the three-person Sea Turtle Research Team in the Northwestern Hawaiian Islands with the NOAA Fisheries Marine Turtle Biology and Assessment Program. It was our job this summer to set up a camp on East Island and study the hundreds of sea turtles that come to this small island to reproduce. While it is not known why approximately 96% of Hawaiian green sea turtle nesting takes place at French Frigate Shoals, we are learning more and more about this phenomenon with each passing field season. This season, we identified 871 individual male and female turtles with a small white number we gently painted onto their shells. On East Island alone we counted 413 females that came up to nest this season, more than last year’s 87 but less than the banner year of nearly 900 in 2014 (because turtles nest every few years, every population has natural seasonal highs and lows depending on which turtles decide to make the migration and nest). Along with numbering each turtle, we also gave each one small flipper tags and took their measurements to track their growth. Since researchers have been tagging in Hawaii for several decades already, it was exciting to find turtles that had tags from 10, 20, and even over 30 years ago!

Sea turtle researcher Jan Willem Staman counts the eggs of a nesting female turtle (Photo: NOAA Fisheries/Marylou Staman).

Because sea turtles nest at night, we had to adjust our sleeping schedule to make sure that we would be awake when the turtles were most active. That meant that our work day actually started around 4pm in the afternoon. Just like in the main Hawaiian Islands, the sea turtles at French Frigate Shoals would haul out onto the beach during the day to bask, or rest in the sun. From 4-6pm we would walk around East Island and record all of the turtles we saw based on the white numbers we wrote on their shells. On our very first day on East Island, we walked around the island and counted 229 basking sea turtles! However, that number steadily declined throughout the summer as more and more females finished laying their eggs and returned to the main Hawaiian Islands. Those females, with our white numbers still on their shells, have now been seen back around the main islands and have become a part of a unique citizen scientist project recently announced by NOAA! (Learn more: By the Numbers, Green Sea Turtles in Hawaii.)

The sea turtle research team didn’t need headlamps to see the turtles crawling up to nest when the moon was up (Photo: NOAA Fisheries/Jan Willem Staman).

After completing our afternoon survey, we would spend a few hours transcribing the data and eating dinner before starting our night survey around 9pm. While in theory walking around a deserted island at night may sound spooky, there was actually so much going on that we didn’t have time to get creeped out. In addition to the dozens of nesting sea turtles crawling out each night, we also encountered sleeping monk seals and restless birds, all lit up by the most impressive display of stars I have ever seen. When the moon was up we didn’t even need headlamps, and when the moon was set, the darkness allowed the stars to light up the whole sky instead. We spent so much time on our night surveys looking for turtles on the ground, that I’d occasionally remind myself to look up, and the night sky always took my breath away.

Sea turtle #252 digs a nest in front of the East Island camp (Photo: NOAA Fisheries/Jan Willem Staman).

When the sun began to rise on the horizon, it meant it was time to do one last lap around the island and head back to the tents. After 8-9 hours of walking laps around our sandy island, the biggest and completely unanticipated challenge we faced each day was still to come: trying to sleep! Between the loud birds and the hot sun, sleeping more than 2-3 hours in a row became a notable achievement around camp and something I do not take for granted now that we’re back here in Honolulu.

The stars shone a little brighter over East Island, where the only other light came from red headlamps the researchers wore during surveys (Photo: NOAA Fisheries/Jan Willem Staman).

Jan Willem and I returned to Honolulu at the end of August and have been busy entering all of the data we compiled over the summer. In order to collect another month of nest data, Alex bravely stayed behind on East Island alone, with daily check-ins from the nearby monk seal camp on Tern Island. Sitting behind a desk in a cubicle is definitely not as adventure-like as carefully sneaking up behind nesting turtles to count their eggs, but we do value the data and enjoy the memories it elicits.

HICEAS Hilite: Diving into the secret lives of short-finned pilot whales

By Amy Van Cise
HICEAS Cetacean Observer

It didn’t take many days into the ongoing Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) to see short-finned pilot whales. They came, during our second sighting of the cruise, as they so often do–meandering slowly through, seemingly unbothered by the flurry of melon-headed whales that were darting around them. You would never guess they are called the “cheetahs of the sea.”

Once underwater, though, they sprint down to the darkness of the deep ocean, up to 800 meters, to hunt for squid and other deep-water prey. Short-finned pilot whales hunt and live their lives in stable social groups of 15-30 animals. When they hunt, half of the group will dive while the other half stays at the surface. The whales will make social calls while they’re separated, so they can find each other when they return to the surface.

Short-finned pilot whales spend most of their lives in pairs, or dyads, and in close companionship with a small group of other animals. Photo credit: NOAA Fisheries/Adam Ü

Behaviors like these have made scientists take a closer look at how important sociality is to short-finned pilot whales. Scientists have found that animals in Hawai‘i spend most of their lives in small groups of close relatives. Those small groups are very selective about what other groups they will associate with, and where they will spend their time. This selective behavior has led to three separate communities in the main Hawaiian Islands–a western community around O‘ahu and Kaua‘i, a central community extending from O‘ahu to Maui, and an eastern community around Hawai‘i Island.

While we know a lot about the eastern and western communities–which families live there, who they associate with, when they dive and hunt–we know very little about the central community. So we were very excited to run into a group of short-finned pilot whales off Maui on August 1, 2017, at the end of HICEAS leg 1 aboard the NOAA Ship Oscar Elton Sette. Using photos we collected during that sighting, we’ll be able to determine if the group we encountered is from the central community, and then use this sighting to increase what we know about that community.

Little is known about the community of short-finned pilot whales that lives around Maui, but by comparing the dorsal fins from animals we encountered on August 1, 2017, to a photo ID catalog of animals around the Hawaiian Islands, we can learn more about where these animals spend their time and with whom they choose to associate. Photo credit: NOAA Fisheries/Amy Van Cise

Short-finned pilot whales are found throughout the tropical and temperate oceans of the world, and for centuries, scientists have thought that all short-finned pilot whales were a single species. But in the last couple of decades, a new picture is beginning to develop: scientists have described two different body types, and then shown that animals with different bodies also have different distributions, vocalizations, and DNA codes. They have called these two types “Shiho” (Shee – hoe) and “Naisa” (Nye – sa) type short-finned pilot whales, and think that they might be separate subspecies or even species. The Naisa type lives in the western Pacific, including the Hawaiian Islands, and is easily distinguishable by its square melon (or head).

The square heads above are a dead giveaway for Naisa type short-finned pilot whales, but you don’t have to worry about telling them apart from other types in Hawai‘i, because we only see the Naisa type. Photo credit: NOAA Fisheries/Amy Van Cise

All short-finned pilot whales that live in Hawai‘i are the Naisa type, but not all are the same. Short-finned pilot whales in the main Hawaiian Islands are genetically distinct from those in the Northwestern Hawaiian Islands or in the open ocean surrounding the islands. And while, with an overall abundance of nearly 20,000 individuals, short-finned pilot whales seem like they are everywhere in the main Hawaiian Islands, they are very difficult to find once you leave sight of land. Once we ventured northwest into the expanded portion of the Papahānaumokuākea Marine National Monument (or Monument), we spent weeks without seeing our predictable neighborhood short-finned pilot whales.

On August 20, 2017, during HICEAS leg 2 on the Sette, we finally caught sight of a group of short-finned pilot whales in the far northwest reaches of the Monument, and it was nothing like what we had seen in the main Hawaiian Islands–these guys were fast. They practically sliced through the water, coming up for only a few breaths before diving again. We launched a small boat from the ship to get better photos and biopsy samples from this group, since we knew it might be one of the few times we ever see them in this remote area. But between their speed, the 6-foot waves, and the impending sunset, we were only able to get a few photos before the whales swam away into the night.

This map of the Hawaiian Islands shows all of the HICEAS survey effort (white lines) through August 22, 2017, with pilot whale sightings shown as blue dots. Most sightings of pilot whales have been close to the main Hawaiian Islands; so far we’ve only found one group of pilot whales far from land. The area shaded in green is the Papahānaumokuākea Marine National Monument, with the expanded portion of the Monument shown with slightly lighter shading.

One of the greatest challenges of studying marine mammals is having the patience and perseverance to collect data. Each sighting of a species or population gives us just a little more information about their behavior, abundance, or ecology, but some species can take days, weeks, or even months to find. We still have so much to learn about short-finned pilot whales in Hawai‘i–so we will keep looking!

For updates about short-finned pilot whales and all the other species we are seeing, keep following us on the HICEAS website!

All photos taken under research permit.

Weaned! The lives and questionable choices of Laysan’s youngest seals

By Hope Ronco, Helena Dodge, and Kristen Tovar

The field team at Laysan Island this summer consisted of Hope Ronco, Helena Dodge, and Kristen Tovar. The self-titled Lovely Ladies of Laysan conducted surveys and collected monk seal population assessment data, but some of the highlights of their season were watching weaned pups learn and grow.

Laysan Island has approximately 250 resident Hawaiian monk seals, which is the most of all the islands and atolls in the archipelago. When we arrived on island, one of our primary goals was to identify all moms and nursing pups. This summer at Laysan, there were 28 Hawaiian monk seals born. They are, without a doubt, the cutest members of the species. When they are born, they weigh between 30-40lbs and are covered in fuzzy black fur. As they nurse and grow, they eventually molt off the dark fur, leaving behind a silvery gray coat. After 5-7 weeks, they have enough fat stores to hopefully sustain them while they learn to survive. Their moms depart, leaving the newly weaned pups to explore and learn how to be a seal, and, like all young ones going out into the big world, occasionally make some unfortunate choices.

Anyone for a SAND-wich? When other objects aren’t around to play with, why not try a mouthful of sand?

Some of our favorite moments from this season were watching weaned pups play in the shallows and keiki pools around Laysan. Weaned pups are a bit like puppies at first- they chew on everything. Sand seemed to be a favorite toy at Laysan this season. Luckily, there is a plethora of sand available! Other toys include shells, rocks, algae, and even some marine debris like plastic bottles and tires.

This playing is also a part of how they learn to hunt, and the slowest prey around Laysan seems to be sea cucumbers. However, when threatened, sea cucumbers expel their insides, which looks like white spaghetti. As you can clearly see in the picture below, this weaned pup got a sticky surprise. Luckily the sea cucumber insides dry and fall off, leaving the weaned pups as good as new and hopefully with a foraging lesson learned.

The sticky guts of a sea cucumber all over this pups face is an indication of some “successful” foraging. We don’t think they actually eat the sea cucumbers, but it is good training looking for food on the ocean floor.

When they aren’t learning to forage, weaned pups spend quite a bit of their time sleeping. This ball of large line washed into the shallows at Laysan this summer, and a weaned pup decided it would be a comfy place for a nap. While this looks adorable, marine debris is a huge threat to Hawaiian monk seals, which as a species has one of the highest rate of entanglements out of all marine mammals. Luckily, this pup was simply sleeping and not entangled. To ensure no curious critters could get ensnared in the ball, we encouraged the pup off the line and then attempted to pull it up onto the beach. Even as we struggled to get the line out of the water, other seals continued to approach and check it out. We were able to beach the line, but it took a team of 11 scientists to eventually roll it out of the water and away from interested seals.

We all agree that it’s been extremely rewarding to be working towards recovering the population of endangered monk seals. We look forward to seeing these goofy weaned pups next year as experienced, spunky juveniles!

 

 

 

 

 

 

 

 

 

 

It Takes Two: The Conservation Adventures of the Loneliest Monk Seal Camp

Keelan B. and Brittany D. comprised our monk seal team at Lisianski Island.  This is the only camp that has only two field researchers making it critical that they get along and can work together.  They had a busy season filled with some strange occurrences and impressive conservation successes.  Here is their tale from a summer in isolation.

Have you ever wondered what it would be like to be one of the last two people left on Earth? What would you do? Or if you were stranded on a deserted island and you could only bring one thing, what would it be? Well, three months on Lisianski Island for a Hawaiian Monk Seal Research Program (HMSRP) Assessment and Recovery Camp allowed my colleague, Brittany, and I to experience just those scenarios. Welcome to Lisianski Island: population 2!

We were tasked with monitoring the island’s sub-population of over 150 Hawaiian monk seals. Our days were filled with some lows – swatting our way through clouds of native flies, wading through waist-high, choppy water and bushwhacking through spider infested vegetation, and some highs – curling our toes in Lisianski’s white soft sand, gazing at the blue-green expanse of Neva Shoals, and bidding aloha to the sun as it set in a crimson sky at the end of a hard day of work. Our island, while short on people, hosted a wide variety of sea birds, including albatross and frigate birds. Red-tailed tropic birds call the island home, and return annually to raise their chicks there; female green sea turtles migrate back to Lisi (short for Lisianski) to lay their eggs under the Milky Way. The heliotrope-ringed coast, leads to one spectacular feature known as “weaner cove”, where the weaned pups learn how to be seals after mom has left them to their own devices, and a long limestone ledge has given the island a reputation for unique beauty; as Brittany would say, “it’s a little magical.”

“Weaner Cove”

Our daily life was far from mundane, always busy and filled with fixing things, maintaining camp and balancing our daily needs with research objectives. Our four tents were graced with albatross and masked booby chick tenants living under the shade of our tent overhang. We watched these tent mates grow and fledge, heading out into the big blue on new wings like so many birds before them. Though our kitchen facilities were less than 5-star, we made due with soufflés and grilled cheeses with red peppers on camp-made bread, or after more exhausting days: soup, mac n’ cheese, or nachos. Our toilet facilities consisted of a long drop, dug deep into the fine Lisi sand, supported by a triangle of plywood boards topped with a toilet seat, exposed to both the starry night sky and the pouring rain. Our sanity and connection to the outside world rested firmly in the grip of a solar system designed to harness the sun’s rays for our satellite devices, computers, and iPads. The island offers no source of fresh water, so we must to bring our own in dozens of 5-gallon water jugs.  Water is precious, resulting in primarily saltwater ocean baths after surveying the entire island.

In addition to our annual mission to identify our seals, disentangle them of marine debris, clean our beaches, tag the year’s new pups, and explore our island home away from home, this season marks the beginning of a large-scale effort to vaccinate monk seals in the Northwestern Hawaiian Islands against morbillivirus. Morbillivirus, a group of viruses which includes canine distemper and measles in humans, has the potential to devastate the already critically endangered species. After many years of discussion, research, and hard work, this summer marked the first ever species-wide vaccination effort to be made on any free ranging marine mammal species. Equipped with a propane-powered refrigerator, two spring-loaded pole syringes, some granola bars and 220 vaccines, we set out to change the fate of a species.

The learning curve was steep, but we rose to the challenge! Our goal? 100 fully vaccinated seals! This goal is especially lofty since each seal requires two doses of the vaccine to achieve immunity; the booster (second dose) must come in a narrow window some three weeks after the initial dose.  Remember these are wild seals, there is no telling if or when they’ll show up for their booster! We were also faced with a limited timeline to complete our boosters, as our vaccines expired partway through the summer season. A massive undertaking, we were ready to give it our all.

We spent many long hours and walked many long miles looking for and observing our seals, choosing the best candidates for our limited vaccines, favoring our adult females and the next generation. We had good days and days that tested us, and of course we had moments where we questioned if we’d reach our goal.  On our last day of vaccinations, we each walked around the island determined to make our goal. On our first sweep, we reached 99 seals fully vaccinated out of the 109 who had been given their initial shot. Not to be defeated, we walked the island one more time finally reaching our goal with the vaccination of the adult male seal, TY73! Though we were too tired to celebrate (or brush our teeth before bed), we went to sleep knowing that two-thirds of Lisi’s seals were safe in the event of a deadly morbillivirus outbreak.

Though vaccinations were the crowning glory of our season, and perhaps our young careers, that project was by no means the only significant work we conducted. We had two eel-in-nose events, following on the heels of last season’s first ever occurrence of this natural oddity. It is impossible to explain what goes through your head when you come across a weaned pup with an eel protruding from a nostril. Though we don’t know exactly how this happens (and we may never know), it goes to show that these unique seals will always keep us guessing!

Additionally, we had 4 entangled seals that needed assistance. We were surprised to see one of our favorite juvenile seals resting on the beach with a 5-foot long Styrofoam block attached to a length of plastic line wrapped tightly around his midsection. With a little quick thinking and planning we were able to loosen the line and leverage the Styrofoam block to pull it completely off. A few days later we found an eel cone (used in the offshore fishing of hag fish and frequently found washed ashore), fitted snugly around a weaned pup’s snout preventing her from opening her mouth. One quick pull and she was free to go about her weaned-pup antics. Our last two entanglements were of a more nefarious nature and consisted of debris wrapped around seals’ necks. The first, a sub-adult male with a piece of rope around his neck, was cut free using a seat belt cutter and some quick fingers. Our last entanglement, a weaned female with a plastic ring around her neck, was freed when we were able to break the ring and pull it free.

Though life in the remote Pacific is not an easy life, it is certainly unique and perhaps a special kind of wonderful. We learned a lot this summer, both about ourselves and about the wildlife we are surrounded by and work to save.   We were honored to be a part of cutting edge conservation work, on the forefront of saving a unique and endangered species.

Lisianski Island, named for its discoverer Captain Lisianski, who shipwrecked on Neva Shoals once upon a time, described the island as “offering nothing to the adventurous spirit”. I think it is safe to say, we could not agree less!

The Root of Everything: Teamwork and the Science of Counting Seals

Darren and his three campmates, Megan, Alix, and Caroline, spent their summer months at Pearl and Hermes Reef counting and saving monk seals.  Darren shares a little bit about how we go about counting seals and estimating the population.  This data and population estimate serves as the foundation of EVERYTHING we are able to do to help save monk seals. But none if it could be done without dedicated people working together.

Our goal, above all else, is to recover the monk seal population. The first step to recovery is having a deep understanding of population size (the total number of seals), and trends (increasing or decreasing), so you know what is working, and just as importantly, what is not, in terms of conservation actions. Mark-recapture is a long-standing method of counting wildlife populations. In species with large populations the idea is usually to mark a portion of the population in some way (maybe tags, bleach marks, shaving a part of the fur) and release them back into the population to mix.  Some time later, more animals from that population are recaptured.  By using the percentage of the recaptured animals that were marked versus unmarked, scientists can estimate population sizes.  With monk seals we have the amazing opportunity to recapture nearly the entire population. This opens a treasure trove of information about the seal population. We not only get a good estimate of overall population size, but also insight into valuable and interesting information such as how well animals survive at different locations, how well different aged animals survive (like juveniles versus adults), number of pups born, inter-atoll movements, and so much more.

To achieve this, two things must happen: the animals must be ‘marked’, and then over the years the animal is ‘recaptured’ with each sighting (as opposed to physically handling them). A ‘mark’ is just a way of saying that the animal needs a persistent and unique marking that identifies them as an individual. In this case ‘recapture’ simply means to positively identify the individuals marked initially.  We do this in primarily two ways. The first method is to tag the animals when they wean with two flipper tags. The second way is to identify individual animals with photos of scars and marks that they have naturally collected throughout their life. Using scars is problematic in young animals that have not had time to collect the wounds that an adult usually acquires with the passage of time.  But some seals never get discernible marks and, over time, animals can lose their tags.  So sometimes scientists must tag, or retag adult animals, to ensure they are captured in our estimates.

The last two times I was at Pearl and Hermes the camp was operated by three people. In the last few years we have added a fourth person to the team in order to produce a safer and more productive camp. This change has also allowed us to address a growing problem for the Pearl and Hermes population of seals.  Our older animals were all losing their flipper tags and our ability to monitor the population was starting to degrade, but an expanded team could help fix that.  Handling adult animals is an activity that is only allowed with four or more qualified people.

Handling large animals has the tendency to bring people to their peak focus. If getting up close and personal with a 500 lb animal doesn’t make everything else in the world fall away, I don’t know what will. For me personally, a big highlight this season was getting to tag some of these animals with our team. We saved these tagging efforts until late in the season when our team was working seamlessly together and everyone had the experience necessary to do the work safely.  This year we had an exceptionally bright and talented group. A good mix of experience, brains, and some muscle to back it up. Tagging these seals has important scientific value as explained earlier, but there was a deeper meaning for the team, as it was a challenge that drew the team together, and how that camaraderie lasted after. I think it was a great reminder for our team that a small group pointed in the same direction is capable of so much more than an individual. It wasn’t simply that we were able to successfully tag these impressive animals, but that we had the focus, communication, and trust that it takes to execute a mission like that safely. There are few things in my life that I enjoy more than working on a team that operates as a unit; where a nod, a look, or a tap on the shoulder communicates more than a ten minute discussion would with other people. This season, after a lot of hard work, we got there. It trickled down into everything we did. As an individual we fail, but as a team we succeed. In my opinion that is a successful season, and I can only hope for more like it in the future.

Darren Roberts

Pearl and Hermes Reef

May 2017- August 2017