Category Archives: Ocean Watch

Green turtles’ numbers are growing at Midway

Published January 13, 2018 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2018 Susan Scott

Green turtles have become abundant on Midway Atoll, choosing to bask in particular on Midway’s Sand Island. An immature green turtle on Midway prepares to eat a Portuguese man-of-war. Courtesy Hope Ronco.

I missed going to Midway this year, but because two friends had flown there early, and they’re back now, I get to enjoy tales of the atoll.

Midway is famous for hosting the largest albatross colony in the world (1 million to 2 million individuals), but it’s also become a place to admire sea turtles. My friends are still marveling over the sight of a green turtle gobbling up a raft of Portuguese men-of-war.

During my first visits to Midway in the 1980s, I didn’t see any turtles. But decades of protection have helped Hawaii’s greens thrive, and as their numbers increase, the turtles are branching out. For reasons known only to the turtles, some routinely swim to Midway’s Sand Island to bask on one particular beach.

On Oahu’s North Shore, seeing nine or 10 turtles dozing on the beach is a good day. Midway’s turtles, though, have made basking practically a team sport.

During my albatross work two years ago, I counted 38 adult turtles sunbathing on that beach, some so close together that their flippers draped over their neighbors’ broad backs. Now this beach sometimes hosts more than 50 individuals.

A few turtles lay eggs at Midway, but the atoll is not yet a significant nesting spot for Hawaii’s greens. Because most turtles return to their hatching place to mate and lay eggs, and green turtles don’t reach sexual maturity until they’re 20-plus years old, it takes decades to establish new breeding colonies.

Limited nesting beaches is one reason Hawaii’s green turtles are still listed as a threatened species. More than 90 percent lay their eggs at French Frigate Shoals, about 500 miles northwest of Oahu and 700 miles southeast of Midway.

Two weeks ago in Midway’s harbor, my friends saw an immature turtle, about the size of a dinner tray, eating trapped Portuguese men-of-war. This was a wind-created pupu platter for the turtle, which took the blue floats, one at a time, into its mouth.

Seeing the creatures’ tentacles dragging over the corners of the turtle’s mouth was cringe-worthy for the human onlookers, but the nasty men-of-war’s stinging cells didn’t seem to hurt the turtles’ skin or tongue.

As my friends and I strolled through Haleiwa Beach Park last week, we came across a friendly and informative turtle and seal guardian, Niko Lopez, from a nonprofit called Hawaii Marine Animal Response, or HMAR.

We learned that volunteers with this citizen science group work with federal and state agencies to patrol, teach, protect and rescue Hawaii’s turtles, seals, whales and dolphins on Oahu and Molokai. HMAR volunteers in 2016 were out 3,700 times, engaging about 56,000 members of the public.

Report turtle or seal injuries or abuse to HMAR at 888-256-9840. For more information or to volunteer with the group, see h-mar.org.

Portuguese men-of-war are remarkable animals in their own right, but they do pack a punch to human skin. Nice to know that our honu are helping keep the rascals in check.

Distinct isle anemones stow their okole at aquarium

Published January 6, 2018 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2018 Susan Scott

On exhibit at the Waikiki Aquarium is a Mann’s anemone, a variety found only in Hawaii. ©2018 Susan Scott

I had no new year’s resolutions this year until I received an email last week from a Honolulu Zoo volunteer who saw a kolea in full spring breeding colors. This was the second person who alerted me to this unseasonably attired plover wintering at the zoo, and off I went with my camera.

Afterward, having experienced a Christmas miracle — a side-street parking space — I walked across the street to the Waikiki Aquarium.

I enjoyed both facilities so much that I promised myself I would visit these wildlife havens more often in the coming year. To cement this spur-of-the moment resolution, I bought 2018 memberships.

Our zoo has fallen on hard times these past few years, but the good news is that the animals are still there and upgrades are in progress. During my search for the dressed-up plover, I spoke to several employees and volunteers, and without exception they were friendly, helpful and upbeat about the zoo’s future.

In light of all the time I spend snorkeling and reading about marine life, you might think that the aquarium wouldn’t hold any surprises for me. But wait, what’s this? On exhibit is an anemone, called Mann’s anemone, found only in Hawaii that I didn’t know existed.

An anemone looks like a single, cylindrical coral body without the hard skeleton around it. Its bottom is a disc that either attaches to something solid or anchors itself in sand or mud. Stinging tentacles surround a central mouth.

The aquarium had several Mann’s anemones, no small feat. The creatures live in intertidal zones exposed to waves and are hard to keep in captivity. The gorgeous pinkish-purple anemones are about 4 inches wide and 2 inches tall. The sign near the animals made me laugh out loud. It says that the Hawaiian name for these animals, is okole, meaning rear end.

The aquarium also has superb sea horse exhibits. As I admired the charming little ponies, a friendly visitor told me that the Japanese name for sea horses translates to “dropped dragons,” another name that made me smile.

I did not find the tuxedoed plover at the zoo during my first spin through, so after the aquarium visit I took advantage of my new zoo membership and popped in for another look around.

That’s one advantage of joining up. Visits can be brief. And if you go at midday you might even find free parking.

During my second spin through the zoo, I found flocks of delighted children and pooped parents, but again, no tuxedoed kolea.

That’s OK. I’ll be back to look again. And during my shoreline swims I’ll keep my eyes peeled for Mann’s anemones.

I know already that it’s going to be a good year.

Isles host 20 species of native spider crab

Published December 30, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

 

Hawaii is home to at least 20 species of small spider crabs. Pictured is one such Hawaii spider crab. Courtesy Morris Moribe

Year-end highlights or summaries aren’t my favorite reading material because the articles mostly contain facts about things I already know. Therefore, for this last Ocean Watch of the year, I’ll share some emails sent to me in 2017 that I loved, and answered, but didn’t have room to publish.

In March, reader Greg wrote, “My coworker found an odd crab … and we were wondering if this is an illegal alien that came to Hawaii during the Navy war games. … It’s a small guy … approximately one inch wide.”

Greg put the crab on ice in his freezer in “solidarity confinement.”

No need to worry about an invasion, though. Greg’s photos showed a spider crab native to Hawaii’s waters.

Hawaii hosts at least 20 species of spider crabs, all oddly triangular shaped. The one Greg’s friend found is common near Hawaii’s shorelines where brown seaweeds wash ashore.

But bring a magnifying glass to examine them. The crabs are only a half-inch to 1 inch wide, as well as being remarkably camouflaged.

Also called collector or decorator crabs, spider crabs have hooked hairs on their bodies that snag bits of seaweed, sponges, corals or other tiny animals drifting past. So besides being small, spider crabs can look like anything but a crab.

Claire, a loyal reader in the Seattle area, brought new facts about another marine animal to my attention last spring in a New York Times link (goo.gl/27XbPN) about fang blennies. (Claire is my 94-year-old mother-in-law who keeps me on my toes via her iPhone.)

Fang, or sabertooth, blennies are little Davids to the ocean’s Goliaths. When a predator fish takes a fang blenny in its mouth, the 2- to 4-inch-long blenny uses its two lower front fangs to bite the captor’s mouth. In response to the pain, the predator spits out the rascal unharmed.

Researchers recently learned that some fang blennies go a step further, injecting an opioid-containing venom during a bite. The venom doesn’t get the predator high, but rather drops its blood pressure by 40 percent.

We humans would feel faint and dizzy with such a drastic BP decrease. Although no one knows how it makes the fish feel, it can’t be good. With its head aquiver, the predator spews out the blenny.

Hawaii hosts several fang blennies but none that pack poison.

Ah, once again, I am out of space and have barely scratched the surface of my 2017 emails.

Readers, please know that I appreciate your personal stories, thoughtful questions, links to news items and words of encouragement. When I’m traveling or sailing I can’t always reply, but I read and enjoy all your messages.

Thank you for swimming with me into 2018. Another year, another 52 fish.

Isolated Midway still has creature comforts

Published December 23, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A pair of Laysan albatrosses sing and dance. The birds bond for a lifetime. ©2017 Susan Scott

 

When I mentioned that Craig and I were going to work at Midway counting albatrosses over the holidays, the questions people asked made me realize that few people know anything about the place.

Reasonably so. Midway may be in the Hawaiian Island chain, but it’s 1,200 miles from Oahu. And even though the atoll holds the Battle of Midway National Memorial, is part of the Papa­hanaumokuakea Marine National Monument and has long been Midway Atoll National Wildlife Refuge, the atoll is not included in the state of Hawaii or even the U.S. You need a passport to go there.

Midway, however, is owned by the U.S., its official designation being a “U.S. minor outlying island.” But don’t dust off your passport. Due to funding cuts to the managing agency, the U.S. Fish and Wildlife Service, the atoll is closed to the public.

When the Navy occupied the place, they called it Midway Island, but Midway is a typical atoll. It consists of three islands totaling 2.4 square miles bathed by a lagoon encircled by a coral reef.

Most people who go there are volunteers for Fish and Wildlife, but getting us there is a monumental task. Given the distance and the poorly named Pacific Ocean, going by boat is not an option. The largest island there hosts an airport, managed and staffed by a few Federal Aviation Administration workers. But no commercial planes currently fly to Midway except in emergencies, which is one of the reasons the government keeps the airport facility open and functional.

We volunteers pay our own charter airfare, up to about $2,500 per seat now, as well as our own meals. Housing is in renovated (and charming) World War II-era buildings that provide electricity, Wi-Fi and private bathrooms.

Not being part of the U.S. means that the contracted manager of the atoll’s facilities, Chugach Alaska Corp., can hire foreign nationals. As a result, about 50 Thai workers maintain the facilities that make Midway life so comfy. A chef named Pong manages the buffet-style meals, half Thai and half American. We albatross counters walk 8 to 10 miles per day, but I still gain weight on Pong’s feasts.

Since 1988, Craig and I have been jumping at any chance to work in this glorious wildlife refuge containing millions of albatrosses, Bonin petrels, white terns, green turtles, monk seals and other animals. But not this year. Due to an airplane glitch, 12 of us volunteer counters aren’t going.

The good news is that the six counters who went on an earlier flight report that the million or so albatrosses there are fine and don’t care if we count them or not. (Biologists care, but that’s another story.) Also, Wisdom, Midway’s 67-year-old Laysan albatross, has laid another egg and is looking as fit and beautiful as ever.

Instead of going to Midway, Craig and I will visit the Kaena Point albies and spend the holidays with our ohana here on Oahu. With alternatives like that, it’s hard to be disappointed.

Merry Christmas, dear readers. You make writing this column a continued joy.

Laysan albatross joins birds visiting isles for the holidays

Published December 16, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

This time of year is perfect for reading about a fictional Laysan albatross’s tale in “A Perfect Day for an Albatross” or watching the documentary “Midway: The Edge of Tomorrow,” which covers the significance of the atoll during World War II with the wildlife that lives there now. ©2017 Susan Scott

Here on Oahu, the holidays are for the birds — shorebirds and seabirds, that is.

In November, we plover lovers added to our list of thanks the first-ever-seen white (called leucistic) kolea, spotted foraging at Heeia Pier.

Late fall is also when Hawaii’s wedge-tailed shearwater chicks leave their burrows and soar to sea. Some youngsters, disoriented by street and shoreside lights, crash-land. Sea Life Park and other caring individuals embody the giving season by helping downed wedgies with rest, nourishment and redirection.

In addition, Honolulu residents and visitors get to enjoy the city’s own version of a white Christmas in the current flurry of white tern egg-laying and chick-rearing.

Topping off our island’s feathery Christmas cheer are Hawaii’s magnificent Laysan albatrosses, returned to nest again at Kaena Point Natural Area Reserve.

Before putting on your hiking slippers to visit the albatrosses (parents are now sitting on eggs, and young birds are singing and dancing for mates), I highly recommend first hitting the couch to read a book and watch a movie.

The book is “A Perfect Day for an Albatross,” written and illustrated by Caren Loebel-Fried, an award-winning author and artist from Volcano, and published by The Cornell Lab of Ornithology.

Loebel-Fried’s work of art is a children’s book in the way Pixar films are for children. Kids love the pictures and story, but the art is so stunning, and Malie the albatross’s tale so well told, that it’s a treat for adults too. A bonus in the book for teachers and home- schoolers is an educational guide for grades 1-3.

The partnership between Loebel-Fried and Cornell is a fine example of the lab’s mission of conservation work through combining scientific research, art and citizen science.

Similarly, the recent documentary “Midway: The Edge of Tomorrow” artfully combines the military significance of the atoll during World War II with the wildlife that now rules there.

You can watch the movie free on Amazon Prime or rent it for $5 for 48 hours. We rented it at a friend’s house, and she emailed that she watched it two more times before it expired. It’s that good.

Speaking of Midway, I’ll be writing next month’s columns from there because I’m going again as a U.S. Fish and Wildlife volunteer to help count albatrosses. The work is strenuous and the cost high (volunteers pay their own airfare and food), but it’s so worth it. See goo.gl/VX4Ph6 for information about volunteering.

Here in the islands, the spirits of Christmas forage, fledge, fish and fly. There’s no place like Hawaii for the holidays.

White terns enjoy growth with the help of humans

Published December 9, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

White terns have taken to urban life, gracing trees between Hickam Air Force Base and Niu Valley. ©2017 Susan Scott

If visions of fairy terns dance in your head this month, they’re not holiday hallucinations. For the second year in a row, Honolulu’s white terns (the official name for what we once called fairy terns or angel terns) are having a banner year.

Fall isn’t usually a busy nesting season for seabirds, but then, Honolulu’s white terns aren’t your usual seabirds. These parents build no nest whatsoever, laying their egg and raising their hatchling on a bare branch.

After the first pair of white terns decided to raise a chick at Koko Head in 1961, others followed until today our island’s south side hosts about 2,300 and counting.

White terns are native throughout the world’s tropic and subtropics, including our Northwestern chain, but Oahu holds the honor of being the only main Hawaiian Island to host a breeding colony of white terns. So far, the birds prefer urban life, gracing trees between Hickam Air Force Base and Niu Valley.

In 2016 and 2017 white terns have had two bursts of egg laying, one in March and another in October. This is a change from the past when, after spring breeding, the birds took time off from chick raising until the next spring.

This is a couple, probably mated for life. ©2017 Susan Scott

No one knows whether this year-round breeding is the new norm here, but it’s encouraging that the charming beauties are so busy. The small fish and squid that white terns eat are apparently plentiful off the city, our towering trees are safe from most predators and people from all walks of life are interested in helping the birds.

The heart and soul of white tern support is Hui Manu-o-Ku, a grass-roots association of tern fans. Among other things, the hui works with researchers, public and private wildlife agencies, and businesses to highlight the tern’s whereabouts.

No one wants to harm these adorable bird families, but in addition, because white terns are protected by federal and state laws, disturbing them can incur a fine. So when eggs and chicks are teetering on bare branches, tree trimmers, landscapers and holiday light stringers want to know.

To call attention to nesting terns, volunteers from Hui Manu-o-Ku and its partners are tying light blue plastic ribbons bearing the organization’s phone number and website around the trunks of trees hosting white tern families.

Volunteers have flagged 85 trees since October 2016 and are enlisting citizen scientists to monitor the terns’ progress.

This is crucial because when the chick fledges, the flag must be removed to keep the system current. People working with trees have been cooperative, helpful and grateful for the heads-up.

How lucky we are to live in a city where real angels decorate our holiday trees. Volunteer to help keep eggs and chicks safe at whiteterns.org or call 379-7555.

It’s the time for ‘wedgies’ to be leaving their burrows

Published December 2, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Grounds workers found a wedgie fledgling stuck in bushes last week, and they delivered it to columnist Susan Scott, who helped the bird launch to sea from Kailua Beach Park. ©2017 Craig Thomas

Years ago, when I fell in love with marine biology, birds didn’t cross my mind. But as I traveled throughout Hawaii and visited other oceanic islands, I discovered that seabirds are among the most amazing of marine animals. They manage to live entirely off the ocean while not actually getting in it or, usually, even on it.

Nor do seabirds live on land. They’re like ideal Airbnb guests, burrowing into our sandy soil (and in the case of white terns, perching in our towering trees) to lay eggs and raise chicks. Then they’re back at sea, going about their airy way.

That’s happening right now with wedge-tailed shearwaters on Oahu. Moms, dads and fledgling chicks are leaving their underground hideaways to ride the wind above the waves.

Wedge-tailed shearwaters, nicknamed wedgies by people who know them, are native to tropical and subtropical waters worldwide. The gray birds with cream-colored undersides are about 2 feet long with a wingspan of just over 3 feet.

Wedgie wings are well known among us sailors because we see the birds far offshore riding breezy air currents just inches above ridiculously boisterous waves. In shearing the water, these birds certainly earn their name.

Adult wedgies arrive on land in March to find, or reunite with, partners, singing mournful songs that sound like a human baby crying or a person groaning in pain. After mating, the couple dig a burrow or move into a vacant one, and the female lays a single white egg.

Parents take turns sitting on the egg for about seven weeks and then sit another week to keep the new hatchling warm. From then on, both male and female go to work each day to bring home the groceries, fish and squid. Adults leave the burrow at dawn, fish all day and arrive back at dusk to feed the waiting chick.

This time of year, wedgie parents are finished feeding, and their youngsters are now emerging from their cavelike homes on Oahu and its nearby islands. Some fledglings make it to the ocean on their first flights, but others get confused by lights and run into wires and poles. These feathered kids wind up on our doorsteps, sidewalks and roads.

But downed wedgies can often be saved. If you find a stunned fledgling, put it in a covered, ventilated shoe box (it grew up in a hole, so the bird is OK with this) and take it to Sea Life Park. For more rescue information, contact official wedgie helpers at Hawaii Wildlife Center or Oahu Seabird Group .

We took the downed wedgie we found in our yard to a nearby wedge-tailed shearwater nesting area. I took its picture in the box. ©2017 Craig Thomas

I thank the seabirds of the world for giving my love of marine biology wings. When it comes to skimming over the ocean’s surface, seabirds are welcome companions.

 

Susan Scott helping a stranded wedge tailed shearwater take flight. The bird is feeling the wind and seeing the ocean as it balanced on her arm. ©2017 Craig Thomas

Posing for a picture. ©2016 Craig Thomas


Minuscule ‘water bears’ are uncanny survivors

Published November 18, 2017
in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A drawing of a water bear, or tardigrade appeared in the scientific journal Acta Zoologica in 1981. Courtesy Acta Zoologica.

I’ve been a “Star Trek” fan from the first show in 1966 to this week when I shouted at the TV, “Hey, that’s a tardigrade!” The writers of the new series, “Star Trek Discovery,” won my heart by incorporating in the plot an adorable animal called a tardigrade, otherwise known as a water bear.

More than 1,000 species of water bears have been named, but researchers estimate there may be as many as 100,000. The reason so many of the little cuties remain to be discovered is that nearly all are microscopic. Water bears are typically 100 to 150 microns long, one micron being one one-thousandth of a millimeter. (One millimeter is the smallest we humans can see with the naked eye.) The giants of the tardigrades are 1.5 mm long.

Although they can’t swim, tardigrades are aquatic, living wherever tiny drops of fresh or salt water form. These minuscule teddy bears are found everywhere worldwide, from hot springs and glaciers to ocean floors, beaches and mountaintops, including those of Hawaii.

If a tardigrade’s film of water evaporates, the plump creature dries up and enters a state called cryptobiosis. The creature’s metabolism slows to nearly undetectable levels, increasing its normal life span of one year to 100 years or more.

In this state, water bears have survived temperatures as high as 300 degrees Fahrenheit and as low as minus 456 degrees. The animals have also lived through vacuums, intense radiation and zero oxygen. (Researchers love testing these potential space travelers.)

Two of my invertebrate zoology textbooks use the terms enchanting, endearing and cute in their introductions to water bears. The tiny teddies trudge around on four pairs of legs. The name “tardigrade” comes from Latin “tardus,” meaning slow, and “gradus,” meaning step.

A few tardigrades are carnivores, but most are plodding vegetarians, never in a hurry to run toward or away from anything.

The teeth and claws of some water bear species look fearsome. Most mouths are telescoping cones bearing needlelike spines called stylets that pierce plants’ cell walls. The contracting legs are tipped with either talons or suction cup toes, depending on the creature’s habitat.

We Trekkies must pay to watch “Star Trek Discovery” on CBS All Access. So worth it! I came home from Australia to find in an early episode a tardigrade named Ripper the size of a grizzly bear with claws and stylet teeth to match. The writers clearly boned up on water bear biology and, except for mass, got it right.

Although the story at first portrays Ripper as a flesh-shredding monster, the sweet-natured tardigrade turns out to be simply hungry and scared. The crew feeds Ripper and sets it free. Of course. It’s “Star Trek.”

Live long and prosper.

Rare white plover adopts boat harbor as winter home

Published November 25, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A rare white kolea has been spotted at Heeia Kea Small Boat Harbor. The bird is likely a leucistic animal, as it has nearly all white feathers but also normally colored eyes, legs and bills, as well as a few patches of color on its feathers. ©2017 Susan Scott

Forget a white Christmas. We bird lovers are dreaming of a white kolea.

Last week reader Bill Coke emailed, “Recently spotted a leucistic Pacific golden plover.” Bill saw the rare bird at Kaneohe Bay’s Heeia Kea Small Boat Harbor. When I forwarded Bill’s pictures to plover expert Wally Johnson at Montana State University, he replied, “Wow! First leucistic plover sighting, Bill. Congratulations!”

Leucism is the term for a genetic disorder in domestic and wild animals in which the creature’s skin, fur or feathers are mostly white. Besides occurring in countless bird species, leucism is seen in nearly all invertebrates, amphibians, reptiles, fish, mammals and marsupials. I once saw a gorgeous leucistic kangaroo in the Irwin family’s Australia Zoo.

“Leu” means “white” in Latin, but leucistic animals are not albinos. A different genetic mutation causes albinism, resulting in no pigment whatsoever. Because blood vessels show through colorless irises, albinos’ eyes look red.

Birds with leucism have normally colored eyes, legs and bills, and most have patches of color on some feathers.

Leucistic animals don’t usually live long. White skin, fur or feathers are like a neon sign to predators that says “EAT HERE.”

Because kolea tend to stay in one foraging site all winter, I drove to Heeia Pier hoping to see this unusual bird for myself. And there stood Blanche (my name) on the curb at the entrance to the harbor parking lot just as Bill described.

In using female pronouns for the bird, I’m guessing. At this time of year, male and female Pacific golden plovers look alike. Come spring, these migratory shorebirds shed their drab winter coats and replace them with the brilliant breeding color feathers we kolea fans so admire.

As for Blanche, time will tell what her post-molt colors will be. The bird will likely stay white, not a good hue for a ground nester in Alaska’s summer tundra. But there’s hope. Blanche fledged in the Arctic, made it to Hawaii and has established a territory.

Several readers have emailed that they are missing their neighborhood kolea this fall, and wondered whether storms in Alaska or the Pacific killed some.

In response to my email query about this, Wally replied, “Given the long flight and life on the tundra, anything is possible. Some birds missing may be just normal mortality.” (Oahu has no official kolea census.)

If you visit Blanche, please don’t startle her into flying. Because she’s so visible, the bird needs her energy to avoid the large number (I counted 35) of feral cats that people feed at Heeia Pier and park.

We might not get white Christmases here on Oahu, but this year nature gave us a gift wrapped in white.

Bleaching isn’t always death knell for corals

Published November 11, 2017 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Many scientists believe that the Earth is headed for a sixth wave of mass extinctions, with humans rushing the rate. Corals will be among those affected, but one small sign of encouragement is that some corals are adapting to changing conditions. Susan Scott snorkels off Kelso Reef, Australia. Courtesy Craig Thomas

Since I returned from Australia last week, people have been asking what I think about coral reef bleaching. Do I believe humans are causing it, and, if so, can we fix it?

The questions refer to reports of corals turning white in areas of Australia’s Great Barrier Reef, and other reports about Hawaii’s reefs. Between 2014 and 2015, scientists found bleaching in 56 percent of corals off the Big Island, 44 percent off West Maui and 32 percent around Oahu.

So-called bleaching occurs when overly warm ocean water causes corals to ditch their algae. The corals’ clear bodies then expose the white calcium carbonate cups that support them.

Researchers theorize that this occurs because overheating causes the plants to make more oxygen, and too much of the gas creates free radicals, a single O instead of the usual O2. Lone oxygen atoms are toxic to animal cells.

The good news is that bleached coral isn’t necessarily dead coral. A coral can live for a while without its plants because its tentacles sting and eat passing animal plankton. When the water later cools, such as after El Nino years, live bleached corals catch algae drifting past in the water. When the plants multiply, they put the color back in corals’ cheeks.

Because bleached corals eventually need carbs, however, if the water stays warm, the corals can’t replenish their crops and die.

This isn’t the first time on Earth that corals have been in trouble. The first reefs formed 490 million years ago, and since then five mass extinctions caused by asteroids, climate change, volcanoes and sometimes more subtle changes killed all reef-building corals. The extinctions took 1 million to 2 million years each, and hundreds of millions of years for new species to evolve.

Most scientists believe we’re on the verge of a sixth extinction. The difference this time is that we humans are rushing the rate. What would normally take 140,000 years for a species to disappear now takes 100.

Homo sapiens is one of those species. In their bright white way, reef-building corals are our putting us on red alert. We are paving the road to our own extinction.

I doubt we humans will mend our ways in time. Our animal instincts to reproduce, fight, and segregate families and tribes from one another make uniting for a common cause tough.

But because species evolve to changing conditions, there’s hope. Some corals are adapting to higher water temperatures and doing just fine. Perhaps, as human and wildlife suffering escalates worldwide, our species will evolve to become less selfish.

In the meantime, there’s tremendous beauty left on the planet, and we should get out there and enjoy it. And who knows? By each of us volunteering to the charity of our choice, we may be accelerating our species’ evolution to altruism.