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Monk Seal Monday #13: RA20

In June 2009, an extra large R5AY gave birth to a chunky female pup on a shallow stretch of sand along a rocky shoreline on Kauai’s north shore. It was mid-day and almost high tide. As tide ebbed and flowed, the placenta, still attached to the pup, kept getting pulled from between the rocks and offshore. Luckily, the assembly of rocks prevented the hours-old pup from getting dragged into open water. Once the tide turned, the little pup was able to stay on dry sand, and eventually her umbilicus released and her placenta fell off. Some weeks later, once the pup weaned, she was tagged RA20–and hardly ever seen again. Because of her healthy size, she was nicknamed “Momona,” which translates from Hawaiian to something like, “very large.”

One year to the day of her birth, a sighting of RA20 was reported to the Kauai HMS Hui hotline. In 2011, she was reported on the east side and south shore on several occasions. Then, she all but disappeared from Kauai. Over the years, periodic sightings placed her on Maui and Hawaii Island.

In 2017, word traveled down the Hawaiian Island chain that RA20 had given birth on Hawaii Island. Unfortunately, three days later, the pup was found dead and floating in a tide pool. A necropsy was performed and a histopathology report supported drowning as the ultimate cause of death. However, other tests showed some abnormalities that may have led to a weakness in the pup and predisposed it to death from drowning and/or trauma. Even with milk found in the stomach, there was evidence of poor nutrition (declining blubber cells, fatty liver) as well as a possible infection in the liver (necrotic cells) and belly button, all consistent in a poorly thriving pup.

But that brings us to 2018.

On February 8, RA20 gave birth to her second pup, boosting the Hawaii Island monk seal population to five resident seals. Reports are that mom and pup are doing well. DOCARE and state park officials have been super supportive and helping that island’s monk seal response coordinator, a member of Ke Kai Ola/The Marine Mammal Center.

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And, so, kicks off the 2018 pupping season. We’ve got more news on that front to come. Meanwhile, enjoy this unusual video submitted by one of our many loyal volunteers. It shows visible stomach movement of Kauai’s resident RK13. Could she be pregnant?

Monachus Monday #12

In 1891, during the height of what’s now known as the golden age of scientific exploration, the first specimen of a Hawaiian monk seal was collected for science. But it wasn’t until 1905, when Dr. H. Schauinsland recovered a skull from Laysan Island in what’s now the marine protected area known as Papahanaumokuakea Marine National Monument that the species’ taxonomy was determined. Given the scientific name–Monachus schauinslandi, the Hawaiian monk seal joined the Monachus tropicalis (Carribbean monk seal) and Monachus monachus (Mediterranean monk seal) in the genus Monachus.

As you may have read a few years back, the Caribbean monk seal was declared extinct. Over in the Mediterranean, their monk seal is staving off extinction with a population of individuals numbering six to seven hundred, about half that of the Hawaiian monk seal.

The cool thing about science is that as technology improves, we can effectively go back in time and re-evaluate things–like that 1905 taxonomic classification of Monachus.

Recently, DNA and skull morphology (shape, size, and structure) was compared across all three monk seal species–using museum study skins in the case of the Caribbean monk seal. The result of this study  determined that both the Hawaiian monk seal and the extinct Caribbean monk seal were quite distinct from the Mediterranean monk seal.

Too, the speciation was estimated to occur with the formation of the Panamanian Isthmus. In fact, the molecular, morphological, and temporal differences between the Caribbean and Hawaiian monk seals compared to the Mediterranean monk seal were so great that a new genus was established–Neomonachus for “New world.”

In a way, this new classification for Hawaiian monk seals as Neomonachus schauinslandi makes Hawaiian monk seals even more rare, because they are the sole surviving species in the Neomonachus genus.

On the subject of genetics, you may have heard Hawaiian monk seals referred to as “living fossils.” An exhaustive genetics study running from 1994 through 2007 revealed the Hawaiian monk seal has lower genetic diversity than any other mammal tested to date, including the cheetah, the northern elephant seal and the North Atlantic right whale. That means there is no genetic difference between Hawaiian monk seals born at Kure Atoll in the northernmost range of the population and those born at Hawaii Island in the southernmost end of the range.

Scientists don’t really known why, but there are theories. It could be a genetic bottleneck occurred due to sealing during the 19th century. It could be possible that the Hawaiian monk seal has never existed in large numbers, and thus has always had low genetic diversity. It could also be that the species was exploited prior to historical record-keeping.

Knowing this helps when it comes to recovery and management practices. It’s one reason for the recent effort to vaccinate Hawaiian monk seals against morbillivirus–to prevent an outbreak of disease.

As science continues to evolve, we can expect the Hawaiian Monk Seal Genetics Research Initiative to continue using molecular science to help in the recovery of the endangered Hawaiian monk seal.

Field Report: January 2018

Sightings:

The Kauai team logged 336 seal sightings this month. This included 34 individually identified seals.

Jan:336
Dec: 270
Nov: 239
Oct: 225
Sep: 354

New Issues:

  • R376, adult female, hooked with small j-hook in lip. Hook came out without intervention several days later.
  • One new juvenile male, untagged and unknown, sighted on West Side.

Updates on previously reported issues:

  • R7AA, juvenile female, was observed with a moderate injury to right cheek, possibly a hook pull-out or moray eel bite. Antibiotics were given. Close monitoring continued, wound currently healing.
  • NG00, sub-adult male, was observed with a circle hook in lower right lip. Sighted on Niihau in January. Photos match pictures sent in by fisherman along Kaumakani in September of a hooked seal. Seal in good condition. Hook not life threatening. Will attempt to de-hook next time hauled out on sand.
  • Poipu Keiki Pool: 3 seals displaced from Keiki Pool.
  • Morbillivirus vaccinations: All vaccines on Kauai have expired. No further vaccinations will occur for the time being.
  • Bleach markings: 1 seal bleach marked this month.
  • Molting activity: no seals molted this month.

Last fall, the Hawaiian Monk Seal Research Program placed dive recording tags on two monk seals that make their home in Kauai waters. We briefly wrote about it here. During one recording period, the two seals (R1KT and R7AA) both made numerous dives deeper than 150 meters (492 feet). One bottomed out at 170 meters (557 feet) and the other at close to 200 meters (656 feet).

These are mammals diving to 500 feet on a single breath of air. But that’s not unusual for monk seals. In fact, the deepest known dive for a monk seal occurred in 2003 when scientists in a Pisces submersible descended to a depth of 543 meters (1,781 feet). They were studying deep sea corals, submarine canyons, and seamounts when a Hawaiian monk seal swam into their field of view. The on-board microphone captured their reaction. It went like this:

“Whoa.”

“What’s that?”

“That’s a monk seal.”

“Oh my god.”

“No way.”

“Look it. Right in front of us.”

“No way.”

“Oh my god.”

So, how do they do it? How do monk seals dive to depths of 1,781 feet?

There are numerous physiological responses involved; collectively the process that allows monk seals to dive deep is known as “mammalian diving reflex.” It involves the respiratory and cardiovascular systems. Typically, before a dive, seals exhale completely. This allows their lungs to completely collapse and avoid gas transfer at depth that could cause nitrogen narcosis. Then, holding their breath, the heartbeat slows from about 125 beats per minute to as low as 10 beats per minute. This is known as bradycardia. A slowing heart rate reduces oxygen consumption. Too, blood is diverted from the limbs and all organs except the heart and brain. This is known as blood shift. It’s accomplished through a process known as peripheral vasoconstriction. Too, diving mammals have high blood volume. That is, elevated hemoglobin and myoglobin levels, which provides greater oxygen storage. The whole idea is to conserve oxygen consumption, so the seal can dive deeper and longer.

Simply, they can hold their breath, slow their heart rate, and direct blood to just the heart and brain. This also helps explain their torpedo-like shape and abbreviated pectoral fins.

Here’s a video of that astonishing 1,781-foot-diving monk seal.

To the casual beachgoer in Hawaii, one Hawaiian monk seal can look just like the next. What appears to be a male monk seal could be a female, and a “mother and baby” pair may actually be juvenile and a newly-weaned pup tumbling in the shore break. Such mistakes are common in the calls to our hotline.

Screen Shot 2018-01-29 at 4.47.31 PMBut when someone calls our hotline to report a seal on Kaua‘i that “has something around its neck,” the seal almost always turns out to be a familiar female known as RK30. If there’s one seal that represents the challenges a monk seal faces in her lifetime, it’s RK30. She is the “poster seal” of monk seal threats.

RK30 first made her presence known in a dramatic way, and she hasn’t stopped, hauling out on virtually every beach around Kaua‘i in the more than 18 years since we first spotted her, even pushing through throngs of people in the water and onshore to find a place to rest at busy sites along the South Shore and East Side.

It all started in 2005 when she was first identified by the Pacific Islands Fisheries Science Center, and it was that “thing around her neck” that got everyone’s attention. It was suspected to be entanglement with a piece of thick line. This was in the early days of these kinds of responses in the Main Hawaiian Islands, and a team gathered and boated to a remote beach along Nā Pali Coast. But RK30 wanted nothing to do with their help. She was already a strong, powerful adult, and she quickly evaded our team.

Luckily, our vet at the time, Dr. Bob Braun, was able to get a good look at RK30 and positively confirm that she had been entangled, but—here’s the good news—that she’d already freed herself of the entanglement. It took a while for her to shake loose of the rope, as evidenced by the remaining, dramatic scar. It suggests the line had been around RK30’s neck for some time—long enough to leave a permanent indentation around her neck that, upon first glance, still looks like she’s entangled today. Luckily, RK30 slipped her noose before a deadly infection could set in and kill her.

Looking back, this was our first sign that RK30 is the extreme survivor she’s turned out to be, because the entanglement scar isn’t her only indication of a brush with death. In addition, she has boat propeller scars on her belly and a large scar on her left side from a possible encounter with a large shark. On top of all that, she has a constellation of 13 cookie-cutter shark bite scars on her body.

Screen Shot 2018-01-29 at 4.47.19 PMRK30’s skill at evading death has helped her species in significant ways—primarily, by adding to the species. To our knowledge, RK30 has birthed at least nine pups. Unfortunately, not all her offspring have survived the way she has. One was lost as a very young pup when a late-season swell washed it out to sea. Another died as a juvenile after ingesting a fishing hook. Her oldest known living offspring is RW06, a female, regularly seen along Kaua‘i’s South Shore and nearing reproductive age.

RK30 was pregnant with another pup (RH38) in 2016 when she was harassed by a man while she was resting out at the ocean’s edge. The man—with a long list of other run-ins with the law—was eventually sentenced to four years in prison by Hawai‘i’s Environmental Court. This was the first conviction under the state’s felony endangered species harassment statue, legislation that was initiated by a few stalwart monk seal supporters and introduced by then-Senator, Gary Hooser in 2010 after a spate of intentional killings of monk seals. A few days after RK30’s encounter with the intoxicated man, she gave birth to a healthy RH38 at one of her regular pupping sites along Nā Pali Coast. And she gave birth to another pup in 2017.

During the more than 13 years we’ve tracked RK30 around Kaua‘i, she’s exhibited some unique behaviors. As tolerant as she generally appears to be around humans, she is no pushover. She’ll bark and lunge at those humans who agitate her. She’s also been witnessed logging just offshore in shallow, calm waters. Too, we’ve received frequent reports of her associating with Green sea turtles—pushing them around, flipping the in the air, gnawing at them. But no reports of her killing or eating one.

We have no doubt that monk seals will continue to surprise us in the future. We just hope it’s not RK30. She’s made enough headlines, although we’d be happy to see her pass on her genes to a half-dozen more or so pups in the remainder of her years.

Monk Seal Monday #9

Come celebrate “The Ocean Around Us.” Lots of fun activities planned. February 2 – 4 will feature “Fins and Feathers” speakers with presentations about Hawaiian monk seals, marine mammals, and seabirds. Volunteers needed. If you’re interested in helping out, please email kauaiseals@gmail.com.

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Field Report: 2017 In Review

Here are a few 2017 year-end monk seal management stats for Kauai:

  • Grand sightings total:
    • 3,621 or 9.9/day monk seal sightings on Kauai in 2017
    • 3,236 or 8.9/day in 2016
    • 3,321 or 9.1/day in 2015
    • 2,516 or 6.9/day in 2014
  • Kauai population: 60 unique individual seals sighted in 2017 (56 in 2016, 53 in 2015, 47 in 2014)
  • Births: 4 total born on Kauai and likely 4 more Kauai females pupped on Niihau
    • 2 pups born on North Shore
    • 2 pups born on Na Pali coast
    • 2 pregnant Kauai females pupped on Niihau observed during Niihau survey (R1KY and RK14). Suspect 2 additional pupped on Niihau based on body condition and timing (RK28 and R313).
  • Mortalities: two observed seal mortality
    • Adult female R4DP found dead at Glass Beach.
    • Male pup RJ22 – carcass found at Hanamaulu Beach.
  • Niihau Seals: sighted 12 new seals in 2017 (6 in 2016, 14 in 2015) likely from Niihau
    • The Kauai team flipper tagged 5 of these.
  • Displacements: 14 total displacements occurred
    • 5 displacements from unsafe or unsuitable locations.
    • 9 displacements from Poipu Keiki Pool.
  • Vaccination for morbillivirus efforts:
    • 17 seals were fully vaccinated on Kauai. 9 were partially vaccinated.
  • Bleach marking effort:
    • 19 bleach marks were applied

Stranding Responses in 2017:

  • 13 monk seal stranding responses:
    • R4DP – found dead at Glass Beach. Transported to Oahu for necropsy.
    • RK13 – monofilament fishing line wrapped around body and removed with longline cutter.
    • RH92 – conditioned to feeding on fish scraps in Lihi canal. Translocated to PMRF while fish scrap dumping issue addressed. Seal returned to Lihi canal area, but no longer forages in the canal.
    • RG22 – hooked and anchored to bottom at Mahaulepu. Tourist cut line free, Kauai team removed circle hook from cheek following day.
    • RG22 – hooked again. Captured and held overnight by the Kauai team until Oahu team arrived to sedate and remove tightly embedded circle hook.
    • RN02 – monofilament observed wrapped around teeth. Disturbed for visual and photo assessment. No hook observed, no further response required.
    • Unknown juvenile approached boat headed to Na Pali, observed with heavy monofilament coming from mouth. Seal never resighted.
    • RK90 – circle hooked removed from cheek.
    • R340 – two large trolling j-hooks embedded in back with heavy line trailing. In three different non-capture responses line cut away and one hook removed. Final embedded hook left to come out naturally, which occurred within two weeks.
    • RH38 – captured and transported to Ke Kai Ola for rehab. Seal was de-wormed, fattened, and released back on Kauai.
    • RJ22 – found dead at Hanamaulu. Transported to Oahu for necropsy.
    • R7AA – moderate injury to right cheek observed. Antibiotics given, seal recovered.
    • NG00 – circle hook in right cheek. Closely assessed. Capture and de-hooking not yet possible.