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Let’s talk smell.

Hawaiian monk seals have two vertical slits for nostrils that are adapted to close when they dive, begging the question how much do Hawaiian monk seals rely on a sense of smell when flipping over rocks on the ocean floor in search of, say, flat fish like flounder? Or when they stick their nose in a puka in rock, hopeful to snag a lobster or eel for a good meal? For that matter, what about when Hawaiian monk seals are hauled out on the beach, and their nostrils are open?

Turns out there are probably more questions at this point in time than there are published scientific papers on Hawaiian monk seals and their sniffing prowess.

Let’s tackle the use of smell on land (air) by taking a look at other seal species. 

Take Antarctic fur seals. According to The Wire, when this species gives birth, mothers nurse their young for some four months. During that time, mothers leave their pups on the beach and head to the sea to search for food. They may be gone for up to 10 days. When they return, researchers suggest mothers rely on smell to sniff out their own pup from the many others on the beach. 

Researchers believe the same is true of Harbor seals.

More closely related to Hawaiian monk seals, the Mediterranean monk seal is also thought to use smell in mother-pup bonding. According to the Eastern Adriatic Monk Seal Project, “…sense of smell plays an important role in the life of a Mediterranean monk seal as scent and sniffing is used intensively in the first weeks of a newborn pup’s life in order to communicate and find its mother in the dark caves where they live.”

Compared to Antarctic fur seals, Hawaiian monk seals nurse their young for a fraction of time—four to six weeks instead of four months. While nursing, Hawaiian monk seals don’t leave their pups alone on the beach to forage. And Hawaiian monk seals birth their pups on beaches, not in caves like Mediterranean monk seals. Interestingly, especially at islands and atolls in Papahānaumokuākea Marine National Monument, it’s not uncommon for pup-switches to occur among Hawaiian monk seals. That is, moms and pups get mixed up. It happened on Kauai in 2018 when there were three moms and pups on the same beach.

Researchers propose there are more uses of smell among Antarctic fur seals. They may rely on “signature scents” to mate with unrelated seals, according to the same article in The Wire. Because fur seals tend to colonize, they may use smell as a way to form stable social groups.

But what about when foraging? How might smell be involved? Steller sea lions possess a large number of olfactory receptor genes, possibly because they are more terrestrial, that might help them hunt for food. 

This unique research paper posits that “aquatic carnivores” forage “noseblind,” that is without airborne chemical cues and, thus, have reduced olfactory anatomy, especially among deep-divers, relative to closely related land-based carnivores. That is, if sense of smell isn’t a critical component to their way of life, the anatomy that supports it diminishes over time in an adaptive response. Why build it if it’s not needed?

Over millennia, Hawaiian monk seals have adapted to their tropical ecosystem in unique ways. They don’t “colonize” in the same ways as some seals. They don’t birth their pups in caves. They spend the vast majority of their lives at sea. They can dive as deep as 1,800 feet; however, average foraging dives of several hundred feet. So, just how great—or not—is Hawaiian monk seals’ sense of smell? Good question.

This will be updated as more information come to light.

Monthly Totals: The Kauai team logged 229 seal sightings this month. This included 29 individually identified seals.

  • October: 229
  • September: 251
  • August: 213
  • July: 286
  • June: 218
  • May: 209
  • April: 155
  • March: 137
  • February: 119
  • January: 125
  • December: 119
  • November: 133
  • October: 152

Updates:

·       Flipper-tagged KP3 (3rd pup of the year) as RP28 and vaccinated for morbillivirus.

·       Morbillivirus Vaccination: RP28 received her initial vaccine this month.

·       Molting: 4 seals molted this month

Research/Support of PIFSC:

·       Sub-sampled scat, molt, and tissue plug samples accordingly.

·       Logged all seal sightings for PIFSC database. Organized photos and reported sightings, molt tallies, survival factors to send to PIFSC.

News from Ke Kai Ola:

Unfortunately, the adult male monk seal known as RW22 died after more than five weeks in care at the Monk Seal Hospital in Kona, Hawaii Island. RW22 was flown from Oahu to Hawaii Island for treatment of a parasitic disease known as toxoplasmosis. RW22 was also suffering from malnutrition, the effects of ingested fishing gear.

Toxoplasmosis is the number one disease threat to Hawaiian monk seals.

In a press release issued by The Marine Mammal Center, Angela Amlin, Hawaiian Monk Seal Recovery Coordinator at NOAA Fisheries, said. “With no vaccine available for toxoplasmosis, preventative measures must be taken by the general public. This disease is spread into the environment exclusively via cat feces. To help protect endangered Hawaiian monk seals like RW22 from toxoplasmosis, simply dispose of cat litter in the trash, keep your cats safe indoors and tell your community about how they too can prevent this disease from harming more marine mammals.”

After canceling last summer’s field season in the Northwestern Hawaiian Islands of Papahānaumokuākea Marine National Monument, NOAA’s field crew returned this spring, staying through the summer, making every day and minute count.

They collected population data, identified individual seals, tagged weaners and yearlings, disentangled seals and turtles, surveyed basking and nesting turtles, surveyed Laysan ducks, staged marine debris for pickup, and assisted in numerous additional conservation and research activities on behalf of conservation partners.

The field crew left civilization behind for tents, canned food, and starry starry nights, and you can read about their efforts and their experiences here in a very thorough report of their tremendous effort. 

https://www.fisheries.noaa.gov/feature-story/challenges-satisfaction-and-lots-monk-seal-pups-during-2021-field-season

Long-time volunteers with the Kauai Hawaiian Monk Seal Conservation Hui will remember working with David Schofield. David served as the point person with NOAA for marine mammal strandings. In his early days, he was also more heavily involved in monk seal response. Now, after 16 years, David has announced his retirement from NOAA, and he’s planning to move to the East Coast and start a Christian outrigger canoe ministry through New Hope Church.

Last week, Hawaii News Now interviewed David about his work at NOAA and his plans for the future. Click on this link to watch the video interview; it provides a good history of NOAA’s work in this field, as well as, a history of David’s hair styles!

David Schofield

With the ongoing recovery of Green sea turtles in Hawaii, some common questions come up:

  1. Is it now legal to harvest turtles for human consumption; and
  2. Is it now legal to harvest turtle eggs?

The answer to both questions is: No. 

Hawaiian green sea turtles—honu—are still protected federally under the Endangered Species Act, and, as well, by state laws. 

Yes, their numbers have improved, but they still face threats, primary among them is sea level rise, due to climate change, and the subsequent loss of nesting habitat, especially on low-lying nesting beaches in the Northwestern Hawaiian Islands in Papahānaumokuākea Marine National Monument. 

What’s more there are dangers associated with the consumption and handling of honu. 

One concern is fibropapillomatosis. Or “FP,” a tumor-causing disease that affects some sea turtles, forming cauliflower-like tumors on the body, often around the eyes and mouth but also internally around organs. FP is closely associated with a herpesvirus. Some sea turtles develop non-threatening tumors; others develop tumors that interfere with vital functions. While some viruses can move from animals to humans and there are similar diseases in humans, there are currently no known cases of sea turtle FP transmitting to humans, according to NOAA.

But consumption of sea turtles—specifically meat, adipose tissue, organs, blood, eggs—can pose a health risk to humans.

According to a scientific study published in EcoHealth reports, “…there may be hazards associated with this consumption due to the presence of bacteria, parasites, biotoxins, and environmental contaminants. Reported health effects of consuming sea turtles infected with zoonotic pathogens include diarrhea, vomiting, and extreme dehydration, which occasionally have resulted in hospitalization and death.” (Update: This study has more to do with the consumption of Hawksbill turtles than Green sea turtles.)

Little can be done to treat Chelonitoxism, considered a type of food poisoning, with only supportive care offered. Symptoms can present within hours to a week following ingestion and recovery can take weeks. Children are particularly susceptible. 

In terms of the effect of turtle tumors on people who might eat them, there hasn’t been too much direct research on that since people haven’t been eating them. 

Remember the recommended viewing distance of sea turtles is a minimum of 10 feet—on land and in water. Because honu are still protected in Hawaii, it’s illegal to harm, harass, or even touch a sea turtle.

Red. That’s almost always the color of tags on Hawaiian monk seals that get flipper-tagged in the main Hawaiian Islands. Red contrasts nicely with the shades of gray that are monk seals.

On rare occasions, however, a Hawaiian monk seal has galumphed up the beaches of Kauai sporting black tags with white lettering. The vast majority of monk seals that arrive on Kauai from Niihau are untagged. But a few are tagged, including NG00, N1AA, and NL04.

A couple weeks ago, a report was made of a monk seal sporting gray-colored tags numbered G89. 

Credit: State of Hawaii DLNR/Lesley Macpherson.

A quick search of the monk seal database revealed that the flipper tag of G89 was associated with a weaner, identified in the scientific database as KG54, a female. She was first flipper-tagged as a weaner in 2015 on Hōlanikū, also known as Kure Atoll. Hōlanikū is notable for its location as the most northern and western of all Hawaiian Islands, some 1,300 miles away in Papahānaumokuākea Marine National Monument.

But there’s an even more interesting story about KG54. It’s this: She was last sighted at Kure Atoll on August 14, 2021 and first sighted on Oahu on September 22, 2021. Here’s the math: She swam an average of 34.5 miles per day in 5 weeks or less.

KG54 is not the only monk seal who has journeyed from Papahānaumokuākea Marine National Monument to the main Hawaiian Islands. More of those stories can be found here

This is yet another example of the importance of reporting any and all seals to the Kauai Hawaiian Monk Seal Conservation Hui by calling and/or texting 808-651-7668. The next island KG54 visits might just be Kauai.

Monthly Update: The Kauai team logged 251 seal sightings this month. This included 30 individually identified seals.

  • September: 251
  • August: 213
  • July: 286
  • June: 218
  • May: 209
  • April: 155
  • March: 137
  • February: 119
  • January: 125
  • December: 119
  • November: 133
  • October: 152
  • September: 152

New:

  • Discovered another new yearling male seal near Kapaa. The seal is likely from Niihau and we hope to flipper tag him soon.
  • Off-leash dogs and irresponsible pet owners continue to disturb seals. Two large dogs were witnessed by the public harassing a large seal at Makua (also known as “Tunnels”). The seal was lunging and vocalizing at the dogs as the dogs continued to circle and bark at it. No physical contact was made. The owner was out snorkeling and did little to intervene once out of the water. DOCARE and the Humane Society were contacted. The Humane Society field officer said they will focus patrols in that area. Additional reports of off-leash dogs were received this month. 

Updates:

  • Adult female RK28 pupped on the north shore on August 10, 2021. The mother and pup (KP3) remained in the area until the pup weaned on October 2, 2021. The nursing period was 53 days. Flipper tagging and vaccination is scheduled for October.
  • The female pup RP20 born at Polihale and translocated to the north shore after weaning has remained in the release area; and has been sighted socializing with other juvenile seals regularly. 
  • Due to COVID-19 stay-at-home measures, our new methods of monitoring continue, which include:
    • Weekly surveys of key areas conducted by staff;
    • DAR staff conducting weekly island wide Creel Surveys;
    • PMRF staff continuing to send in routine reports and photos; and
    • Requesting that people who call the hotline to report seals assist us by sending several photos and setting-up SRA signs or sticks. 

Morbillivirus Vaccination: RP32 received her initial vaccine this month.

Molting: Four seals molted this month.

Volunteers:

  • The volunteer response program was restarted in a modified form in June after being on hold since March, 2020. Currently, volunteers are dispatched for hauled out monk seal reports to post signs, assess and ID the seal, collect routine data, and then depart the area. Outreach/education should be as minimal as possible to reduce COVID exposure risk. For busy locations, a spot check schedule will be established. This technique has proven effective and will continue until further notice.
  • The training of new volunteers has been on hold due to COVID Delta variant surging. Program information and follow-up emails sent to new recruits.

Research/Support of PIFSC:

  • Subsampled KP3 tissue plug for NOAA PIFSC.
  • Sub-sampled scat, molt, and tissue plug samples accordingly.
  • Logged all seal sightings for PIFSC database. Organized photos and reported sightings, molt tallies, survival factors to send to PIFSC.

Over the years, the Kauai Hawaiian Monk Seal Conservation Hui has collected hundreds and thousands of photographs from volunteers of numerous and oodles of individual seals, especially moms and pups. Now, thanks to those photographs, the team has been able to positively identify the untagged female who gave birth earlier this summer to a pup (RP20) at Polihale.

Turns out, she was a known seal, after all. All it took was a good clean look at some tell-tale scars. The good look came after she molted post-weaning.

So, here’s the big reveal: Polihale Mom is R400.

For several years, R400 birthed late in the summer along Na Pali coast; however, last year she was sighted on Oahu (for the first time) in July, and she did not look pregnant. Evidently, she took a year off before returning to Kauai to give birth to RP20.

Here are some scars that led to the identification of Polihale Mom as R400:

  • Semi-circle lower left back;
  • Cookie-cutter shark semi-circle anterior left front nipple;
  • Neck scar that varies in appearacne
  • Unusual line scar 3rd digit left fore flipper;
  • Lighter scars include teeth rake marks lower back, two canine tooth punctures, and parallel lines mid-back, visible in 2021, likely will fade. 

Here are just a few photos (credit M. Olry & J. Thomton) of R400 (and her scars) over the years.

There’s a new girl on island. Nope, not a pup. A juvenile. She made her first appearance in early September, and because she was reported in the same place as another similarly-sized juvenile seal, a male, had been recently seen, it was thought she was he. He had first been identified in July.

Neither are flipper-tagged and, for now, the male is known as Temp606 and the female as Temp607. So, not only are they similar in size and age and frequently sighted in the same area, they have similar identification numbers!

But there are differences (if sex is not readily identifiable), mainly in scars and natural bleach marks, so a close look (preferably through binoculars), can result in correct identifications.

Here are some notable identifiers for Temp606:

  • Two parallel line scars below his right fore flipper;
  • a V scar on his upper chest; and
  • Three white nails (a natural bleach identifiers) on his right fore flipper.

Temp607 is a very wary seal and spooks easily into the water. She also has her own unique set of scars:

  • Two pits scars on her back–one lower and one mid; and
  • Puncture-type wounds on the top of her head.

Photo credit: M. Olry and V. Poelzl.

When a monk seal hauls out on the beach with wounds on its back, the most common explanation is male-on-female aggression. That’s why earlier this month when a seal rolled onto the beach with a nasty wound on its back, the individual was suspected to be female. Too, the animal was tagged; however, the only visible characters on the very worn tag were “31.” That led to the conclusion the animal was female RF30 (with flipper tags F30 and F31).

However, on a closer look at the animal’s scars and tag in photographs, it was determined the monk seal was not F31. In fact, she wasn’t even a she. The wounded animal was, in fact, adult male RN30–with flipper tag N31. Subsequent photographs confirmed it.

While male-on-male aggression is rare, especially in the main Hawaiian Islands, it’s not novel. The behavior has been witnessed in the Northwestern Hawaiian Islands and is suspected to be related to skewed male-to-female sex ratios. The aggressors tend to be subordinate males ganging up on females. (Like we reported here.) But they can also gang up on adult dominant males.

According to this paper, high concentrations of subordinate males in an area of few females can lead to aggregate aggression. Also, “…much of the evidence gathered to date suggests that aggressive incidents may be more likely to result from a ‘numerical’ failure, where a male that is capable of exerting dominance over 1 or 2 competing males is overwhelmed by a larger number of competitors and is unable to prevent their access to a female.”

The paper shares one particular event: “At the onset of an aggressive onshore attack observed in 1985, an attending male defended a female from a succession of 4 male challengers that remained nearby. Eventually, one of the ‘defeated’ males made a second attempt, and as he fought the attending male, another male rushed in. The defending male rushed back towards the female, followed by all remaining males, and was quickly overwhelmed (Johanos & Austin 1988).”

Earlier this summer, a group of males was video’ed mobbing a female off Lehua, suggesting there may be many subordinate males present off Lehua and Niihau. It’s not known whether N30 is a dominant or subordinate male, but it’s clear he was attacked. Perhaps N30 got mixed up in something similar to the anecdote shared above. Earlier this year, he was observed competing with RN44 for RB00 when she was with PK1. He’s also been sighted at PMRF, a popular spot for seals heading to and/or returning from Niihau. In fact, he was sighted (with no wounds) at PMRF on July 30th. He was next sighted on Kauai’s north shore and reported to the Kauai Hawaiian Monk Seal Conservation Hui on September 4th–bearing the mobbing wounds.

These mobbing wounds can look pretty dramatic. But monk seals have an amazing ability to heal and already, N30’s wounds are healing.

Photo credit: Olry and Megonnell