Category Archives: Research

Amusing Monday: Glowing fish are both beautiful and amazing

Science merges into art in new studies of biofluorescence, in which researchers identify colorful marine creatures that glow in the dark. Their ultimate goal is to figure out why.

Biofluorescence is essentially the “black light” effect, in which organisms absorb a narrow frequency range of blue light and transform it into other colors, such as green and red. In deep water, blue is the only frequency of light that makes it through.

Until recently, there was no technology to capture images of fluorescent fish in extremely low-light conditions. Artificial light ruins the effect, and older low-light cameras were too bulky to travel underwater. New cameras developed at Yale University changed the ability of research divers to capture colorful images of sea creatures and bring them back to the surface for further study. So far, more than 180 biofluorescent fish species have been identified.

David Gruber, John Sparks and others are trying to figure out if there is a reason that some fish produce a glow. They would also like to know which of the other creatures are able to see them in the darkness. Check out the article in the journal PLOS ONE published Jan. 8.

Gruber notes that camouflage fish — those able to blend in with their surroundings in regular white light — are often those that stand out brilliantly in fluorescent light. He speculates that fish of the same species are better able to see them, offering advantages in communication and mating. For the sake of these glowing fish, it would be nice to learn that their predators cannot spot them so easily.

The natural beauty of these fluorescent patterns is not overlooked by Gruber and his associates.

“I just find a real serenity and beauty being on the reef at night,” Gruber says in the first video on this page. “And now when we add on this kind of fluorescent layer, it’s like being on another planet.”

Last week, National Geographic published the latest installment in its Emerging Explorers series featuring Gruber and including a new video about his studies called “David Gruber: Seeing the Ocean in Neon.”

Unmanned aircraft provides unique views of killer whales

Unmanned aerial vehicles, commonly called drones, could play an increasing role in killer whale studies, according to Brad Hanson, a researcher with NOAA’s Northwest Fisheries Science Center who has been studying Puget Sound’s orcas for years.

Brad said a plan to use UAVs (he doesn’t like “drones”) has been on the drawing board for several years. Unmanned aircraft can fly over the whales far more cheaply than a full-size helicopter, which has been used in the past. The small aircraft also may be able to come in close for biological samples with less disturbance to the whales than when operating from a research boat.

“I’ve been looking at this for a long time,” Brad told me. “We have it in our (Endangered Species Act) permit to be able to use a UAS (unmanned aircraft system).

Remote-controlled aircraft have been used by researchers to study seals and penguins in the Arctic and to estimate their populations with less disturbance than approaching the animals on the ground. They’ve also been used to count birds in remote areas.

In August, NOAA and Vancouver Aquarium researchers teamed up to test the use of a remote-controlled hexacopter as they observed Northern Resident killer whales in British Columbia. Mounted with a high-resolution camera, the copter captured some amazing videos and still pictures, including those on this page. See also NOAA’s website.

One can learn a lot from a good aerial view of a killer whale, including general body condition, Brad told me. From a boat on the water, it is often difficult to tell if an orca is healthy, underweight or pregnant. From above, a whale’s girth is easier to assess.

Researchers involved the British Columbia study — including John Durban of NOAA’s Southwest Fisheries Science Center and Lance Barrett-Lennard of Vancouver Aquarium — identified several females who seemed to be pregnant.

They also spotted two whales that seemed emaciated. Those animals later went missing and are presumed dead, confirming that they were in poor health. What is not evident from photos, however, is the cause of the problem, Brad Hanson said. Were the whales suffering from disease, injury or another problem that caused them to lose weight, or was it simply a lack of food?

Aerial photos also can be used to measure the length of a whale and, over time, determine the growth rate at various periods in its life.

Brad said the ultimate goal is to develop health assessments for the Southern Residents, listed as “endangered” under the federal Endangered Species Act. A lot of technical details need to be worked out, he said, but the plan is to use unmanned aircraft to collect breath and fecal samples from the whales.

A breath sample is the next best thing to a blood sample, Brad told me, and fecal samples provide information about stress hormones, potential pathogens and other things.

“If you tied that in with imaging, we might be able to build individual health profiles and begin to understand when something is going wrong,” Hanson said.

Currently, breath samples are taken by driving a boat alongside the whales and holding out a pole with an apparatus on the end. Fecal samples are taken by following the whales and sifting feces from the water.

If a small helicopter flown from a boat some distance away can be used, the result would be less intrusive than a boat coming near the whales.

In the study in British Columbia, the general goal was to keep the UAV at least 100 feet above the whales. The study also included some closer movements to test the reaction of the whales. No obvious changes in behavior were noticed, Brad said.

One permit still is needed for Hanson to operate a UAV in Washington state. The Federal Aviation Administration must issue a certificate of authorization, or COA, which spells out limitations of the flight to avoid other aircraft operating in the area.

The Canadian experiment received similar permits from Fisheries and Oceans Canada and Transport Canada. The aircraft was an APH-22 marine hexacopter built for NOAA by Aerial Imaging Solutions.

Ironically, amateurs in the United States are allowed to operate unmanned aircraft in some areas without permits. But flying around wildlife could create unanticipated problems for the animals. And anyone operating around endangered whales could be in violation of other state and federal laws — such as the Endangered Species Act or Marine Mammal Protection Act — if they fly below 1,000 feet.

Orcas vary in physical condition. The female at top appears skinny and in poor health. The female in the middle appears healthy. The one at the bottom is pregnant, her body bulging at the ribcage. Photo courtesy of NOAA, Vancouver Aquarium
Orcas vary in physical condition. The female at top appears skinny and in poor health. The female in the middle appears healthy. The one at the bottom is pregnant, her body bulging at the ribcage.
Photo courtesy of NOAA, Vancouver Aquarium

Steelhead could be running into a trap at the Hood Canal Bridge

Fishermen fish for salmon north of the Hood Canal bridge, but researchers say the bridge may be an obstacle to the migration of young steelhead. Kitsap Sun photo by Larry Steagall
Fishermen fish for salmon north of the Hood Canal bridge last week, while researchers say the bridge could be an obstacle to the migration of young steelhead. // Kitsap Sun photo by Larry Steagall

I’ve often wondered if the Hood Canal bridge might be an obstruction for killer whales, which could simply choose to back away from the wall of floating pontoons, which are anchored to the seabed by a confusing array of crisscrossing cables. Old-timers have told me that orcas used to come into Hood Canal more frequently before the bridge was built.

What I never considered seriously, however, was that the bridge could be an obstacle for fish as well. In Sunday’s Kitsap Sun, I wrote about recent findings from a study tracking juvenile steelhead by means of implanted acoustic transmitters. The study was conducted by researchers at NOAA’s Northwest Fisheries Science Center.

GraphicTemp

The bottom line is that something is happening at the bridge, where many of the transmitters either disappeared or winded up staying in one place near the bridge, continuing to send out their signals for weeks. The leading hypothesis is that seals or other predators are eating the young steelhead, and some of the acoustic tags are being digested and excreted near the bridge.

Why the bridge serves as an obstacle to steelhead remains unclear. But other studies have suggested that steelhead swim near the surface. As they move out of the canal, the fish may encounter the bridge pontoons as a physical barrier, since the concrete structures go down 12 feet underwater. Also, currents around the pontoons could be a strange condition for the fish. If a young steelhead slows down in the process, a harbor seal or other predator could be waiting to take advantage of the situation.

We’ve all heard about sea lions capturing adult salmon by hanging out at fish ladders at Seattle’s Ballard Locks in Seattle or at Bonneville Dam on the Columbia River. Maybe the same thing is happening at the Hood Canal bridge with smaller prey as the target of the marine mammals.

I was also intrigued by an analysis conducted by Tarang Khangaonkar, a researcher at Pacific Northwest National Laboratory in Seattle. He told me that in all the models of circulation in Puget Sound and Hood Canal, the bridge tended to be ignored. Since the pontoons go down 12 feet, the bridge disrupts the relatively thin low-salinity surface layer moving out of Hood Canal.

Tarang calculates that the bridge could reduce the circulation by 10 percent or more, which has serious implications, not just for steelhead at the bridge but for the ecological health of all of Hood Canal.

“We have to examine what the bridge is doing,” Tarang told me. “It slows the entire system down. Water quality is maintained in Puget Sound by the flushing effect, which flushes the system out and maintains a balance. Our preliminary finding is that it could slow down by about 10 percent. That effect is cumulative.”

The bridge, he said, could effectively create a more stagnant body of water, where oxygen can become depleted. More study is needed, he said.

Most of the folks I interviewed for this story agreed that the first priority for further research was to see what is happening to the steelhead — and possibly chinook and chum salmon — at the bridge. Studies could focus on the fish, predators and currents at the bridge.

The project is gaining support, but it could require a special legislative appropriation of about $2 million.

Amusing Monday: Amazing drones bring us new stories to tell

Unmanned aircraft, commonly known as drones, are taking over the world. At least it seems that way. If you don’t believe me, search for “drone” on YouTube. You’ll find amateur aviation specialists — and a variety of professionals — demonstrating what drones can do. Some of the things are pretty amusing.

I’ll mention some water-related drone stories below, but the first video on this page shows a hawk attacking a drone owned and operated by Christopher Schmidt, a 30-year-old software developer. I think Chris did a nice job of protecting the bird by throttling down the props on his Phantom FC40 quadcopter. The final result is a great up-close view of an angry bird, well deserving of a place in “Amusing Monday.”

Chris was using the drone to get images of changing leaves in Magazine Beach Park in Cambridge, Mass., last Wednesday, when he saw a bird circling a good distance away. The circling continued as the bird moved closer to the drone.

“Overall,” he told me in an email, “I was surprised by how quickly he moved from 400 feet away to on top of the quad. When he was very nearby, my initial thought was, ‘Okay, stay still, so he can avoid it’ — which obviously didn’t work out for me.”

Christopher Schmidt with his Phantom drone. Photo courtesy of Christopher Schmidt.
Christopher Schmidt with his Phantom drone.
Photo courtesy of Christopher Schmidt.

He said he saw no evidence beforehand that the bird was upset or likely to attack. Over the six months he owned the drone, nothing like that had happened, except for a few crows squawking at the aircraft. After he posted the video, he learned from bird experts that immature red tail hawks have not yet learned to hunt efficiently, so they may attack anything that moves.

As the hawk attacked, Chris cut power to the props, which caused the quad to drop. The bird hit the chopper and it flipped. Chris was unable to recover the flight, still worried about the bird, though he powered back up at the end.

“If I had done nothing,” he wrote, “I expect the quadcopter would have done the flip (which it did) and immediately recover — possibly losing about
10 feet of altitude. My fear in that case was that the hawk would still
see it as a threat and come back a second time. Well, really, it was
about a half second, so I was not really thinking that much through it.

“I still would do the same thing if I had to do it all over, even if it might have put the quadcopter at less risk.”

The hawk appeared to be fine after the attack. Photo courtesy of Christopher Schmidt
The hawk appeared to be fine after the attack.
Photo courtesy of Christopher Schmidt

As it turns out, the quad sustained almost no damage from falling out of the sky and hitting the ground, except for a slightly bent landing gear. And the hawk was no worse for wear.

Lots of media have been using the footage that Chris took. Based on a suggestion from a coworker, he is donating any money raised from YouTube ads to the American Audubon Society. Thanks to Gene Bullock of Kitsap Audobon for alerting me to this video.

OK, so what are some other odd things that drones can do? How about helping out with an ALS ice bucket challenge? In the second video, Austin Hill of Spark Aerial uses a massive DJI S1000 Octocopter to lift a bucket of ice water and pour it rather slowly on his head.

I’ve shown you videos of the Flyboard®, an apparatus developed in France by Franky Zapata. See Amusing Monday, Oct. 15, 2012. Martin Schumacher goes one better by using a DJI Phantom and GoPro Hero 3 to shoot an up-close demonstration video around Saint-Tropez in Southeast France.

It was only a matter of time before someone got the idea to use a drone for fishing — no matter how inefficient that might be. Check out this 7-minute video by NightFlyer (the action starts about 5 minutes in) or this shorter 1.5-minute video by RYOT. Both these guys now have fish stories to tell. But, after all that work, even they would admit that the fish they caught are rather amusing.

On a more serious note, there are many legal issues related to drones, which are not yet approved by the Federal Aviation Administration for commercial use, and there are many concerns related to privacy. People also are raising questions about whether drones should ever be used for hunting or fishing. Michael R. Shea tackles the subject for “Field and Stream” magazine.

If sportsmen are thinking about using drones, game wardens are not far behind, as they consider how drones might be used to catch poachers. “National Geographic” looks at the use of drones in high-seas fisheries enforcement.

Meanwhile, Gov. Jay Inslee of Washington vetoed a bill that would have limited the use of drones by law enforcement. He then set up a task force to look at the entire subject. A representative of Washington Department of Fish and Wildlife said in one task force meeting that there could be applications for enforcement and research by the agency. The Unmanned Aircraft Systems Task Force is expected to make recommendations before next year’s legislative session.

Killer whales expected to head south any day now

UPDATE, Oct. 4
Orca Network reported a brief appearance of J pod this week near San Juan Island: “On Wednesday, October 1, J pod plus L87 Onyx and a few K pod members shuffled in small groups spread out up and down the west side of San Juan Island for over eight hours, then returned around midnight and continued vocalizing near the Lime Kiln hydrophones for another few hours.”
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As chum salmon swim back to their home streams in Puget Sound this fall, three killer whale pods — the Southern Residents — can be expected to follow, making their way south along the eastern shoreline of the Kitsap Peninsula.

Whale viewing locations by Orca Network. Click on image to view Google map.
Whale viewing locations by Orca Network. Click on image to view Google map.

These forays into Central and South Puget Sound could begin any day now and continue until the chum runs decline in November or December. The Southern Residents, which typically hang out in the San Juan Islands in summer, have not been spotted for several days, so they are likely somewhere in the ocean at the moment, according to Howard Garrett of Orca Network.

This year, Orca Network has created a map of good viewing sites to help people look for whales from shore. As the orcas move south into Puget Sound, Orca Network’s Facebook page becomes abuzz with killer whale sightings. Observers can use the information to search for the whales from shore.

From my experience, it takes a bit of luck to find the orcas, because they are constantly moving. But the search can be fun if you consider it an adventure and don’t get too disappointed if you don’t find the whales right away.

Howie said expanding the network to include more land-based observers can help researchers track whale movements and occasionally go out to pick up samples of their fecal material or food left over from their foraging, helpful in expanding our knowledge about what they are eating.

Whale reports may be called in to Orca Network’s toll-free number: (866)-ORCANET, emailed to info@orcanetwork.org, or posted on Facebook, www.facebook.com/OrcaNetwork.

The new Viewpoints Map shows locations where killer whales have been sighted in the past, or else they lie along a known route of their travels.

I told Howie about a few good viewing locations in Kitsap County, based on my experiences, and he said he would welcome ideas from others as well.

“It’s a work in progress,” Howie said. “They just need to be locations that are public and accessible.” If you know of a good whale-watching spot, you can contact Howie or his wife Susan Berta by email, info@orcanetwork.org.

If offering a location for the map, please give a clear description of the site and state whether you have seen whales from that location or just believe it would work based on the view of the water.

Some people have expressed concern that real-time reports of whale movements may encourage boaters to go out and follow the orcas in Puget Sound, disturbing their feeding behavior at a critical time of year. But Howie says Orca Network has increased its reporting through the years and has not heard of many problems.

“It seems like a potential problem that never really happens,” he said.

Winter weather and rougher seas makes it difficult to find the whales from the water, Howie noted. As in summer, boaters are required by federal regulation to avoid interfering with their travels. See the “Be Whale Wise” website.

When reporting whale sightings to Orca Network, observers are asked to list the species, location, time, direction of travel and approximate number of animals. When reporting killer whales, the number of adult males with towering dorsal fins should be noted. Also report any behaviors, such as breaching, spy-hopping or feeding. Good photographs are especially valuable.

Sighting reports can be found on the Orca Network website, Facebook page or Twitter feed. One can also sign up for email alerts from the website, which includes reports of recent sightings as well as archives going back to 2001. The site also tracks news and research developments.

As Howard stated in a news release:

“We are very fortunate to live in a place where we can look out from nearby shorelines and see those majestic black fins parting the waters. We are thankful for the hundreds of citizens who report sightings each year, providing valuable data to help in recovery efforts for the endangered Southern Resident orcas.”

Orcas Dyes

Celebrating freedom for the Elwha River

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Elwha Prigge

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I want to recognize the Kitsap Sun’s editorial cartoonist Milt Priggee for capturing the feeling of the moment last week when the final piece of a dam on the Elwha River was blown up. See Water Ways, Aug. 27, 2014.

The video below was recorded on that same day by Anne Shaffer of the Coastal Watershed Institute while snorkeling in a kelp bed in western Freshwater Bay, not far from where the Elwha River flows into the Strait of Juan de Fuca.

Watching this video and the large number of herring gives me a feeling of optimism, although I recognize there is no scientific basis for this. Someone please tell me the herring are doing better.

“We couldn’t think of a better place to be the day the last dam went down,” Anne said in an email to members of her listserv.

The Coastal Watershed Institute has been monitoring the nearshore area, where the Elwha River has been dramatically transforming the delta. Sediment, unleashed by dam removal, pours out of the Elwha and builds up in the estuary.

Tom Roorda, an aerial photographer, has been documenting the transformation with thousands of pictures he has taken over the past several years.

Tom Roorda of Roorda Aerial photography captured this image showing the ongoing buildup of sediment at the mouth of the Elwha River. Photo by Tom Roorda
Tom Roorda of Roorda Aerial photography captured this image showing the ongoing buildup of sediment at the mouth of the Elwha River. // Photo by Tom Roorda

Amusing Monday: Crack appears in Mexican desert

For this week, let’s call it “Amazing Monday.” When I first saw this video, I thought it was a fake animation for a science fiction film. But it turns out that it could be the answer to a troubling riddle: What is dryer than a desert?

The crack might also be the result of erosion from either an underground or surface channel following an unusually heavy rain. Despite the attention in Mexican and U.S. news outlets, I have been unable to find a good explanation.

The crack is said to be about three-fourths mile long and up to 25 feet deep. Some nice close-in photos were posted on the website of Excelsior, a daily newspaper based in Mexico City. They show people standing next to the giant fissure. (When watching the video, it’s worth blowing it up to full screen.)

In a Washington Post story last week, reporter Joshua Partlow quoted a geologist at the University of Sonora as saying the crack was probably caused by pumping groundwater for irrigation:

“The chair of the geology department at the University of Sonora, in the northern Mexican state where this ‘topographic accident’ emerged, said that the fissure was likely caused by sucking out groundwater for irrigation to the point the surface collapsed.

“‘This is no cause for alarm,’ Inocente Guadalupe Espinoza Maldonado said. ‘These are normal manifestations of the destabilization of the ground.’”

I think the geologist’s comments were meant to quell fear and speculation that started running wild when the crack first opened. While it may not be cause for alarm, I can’t believe that a crack this size — which has cut off more than one roadway — can be considered a good thing. Nevertheless, it is fascinating, and I’d like to learn more about it.

Amusing Monday: Baby turtles race for the sea

The sand was smooth and still. Waves lapped at the distant shoreline. A sign, stuck in the sand, stated, “Do not disturb. Sea turtle nest.”

That was the scene on a beach in the Florida Keys for the past few weeks, as it was in June, when I posted a blog entry listing cameras that were capturing live action in bird nests as well as other wildlife locations. A quiet patch of sand was not much to look at, so I didn’t mention it.

On Friday, that patch of sand came to life, as you can see in the first video on this page. I thought it was time to share the brief action, as about 100 loggerhead turtles emerged from the sand and headed out to sea about 9 p.m. Check out the action in full-screen.

The camera on the beach uses infrared lights to capture the images, thus avoiding visible light that could confuse the young turtles. The project is supported by Save-A-Turtle, a volunteer non-profit group dedicated to the protection of rare and endangered sea turtles and their habitats in the Florida Keys.

Meanwhile, some of the young ospreys shown in their nests back in June have fledged, but there is still plenty of action in the nest at Missoula’s Riverside Health Care Center, where the camera is operated by the University of Montana. Check out the images in full-screen, high-definition while you can, because these growing chicks will soon be gone.

Another still-active osprey nest is operated by Chesapeake Conservancy on Maryland’s eastern shoreline.

The Puffin Cam at Seal Island National Wildlife Refuge in Maine is picking up some excited feeding activity at the nesting area, where experts are establishing a new colony of puffins after hunters wiped them out in the 1800s.

Brown bears are now feeding on salmon along Alaska’s Brooks River in Katmai National Park, according to bloggers on the site. Check out the live video below to see if you can spot a bear, including a subadult mentioned by observers.

You may wish to go back to the June 23 “Amusing Monday: A visit with wildlife via webcam” to see what other cameras are picking up activity. You can generally count on Pete’s Pond on Mashatu Game Reserve in Botswana, Africa, for some exotic animals coming to the watering hole.



Broadcast live streaming video on Ustream

Stormwater: Can we stop the menace we created?

I’ve completed the seventh story package in a 10-part series examining the Puget Sound ecosystem, with a special focus on indicators of ecological health. We’re calling the project “Taking the Pulse of Puget Sound.”

Jenifer McIntyre of the Washington Stormwater Center studies the effects of stormwater after it passes through filters made of compost and soil materials, such as what is used in rain gardens. The filters are working, even though the most dangerous pollutants remain unidentified. Photo by Meegan M. Reid
Jenifer McIntyre of the Washington Stormwater Center studies the effects of stormwater after it passes through filters made of compost and soil materials, such as what is used in rain gardens. The filters are working, even though the most dangerous pollutants remain unidentified. / Kitsap Sun photo by Meegan M. Reid

The latest stories, which ran Sunday and Monday, addressed freshwater quality. The opening piece looked at the huge amounts of pollution coming into our streams via stormwater — one of the highest priorities for cleanup, yet one of the most difficult to deal with.

As the Puget Sound Partnership’s executive director Sheida Sahandy told me, industrial discharges are still a concern, but they are no longer the biggest problem.

“Now we’re dealing with stormwater, which is trickling in here and trickling in there, and everybody has a finger in it,” she said.

Solutions are many, and the goal should be to shut off pollution at the source, beginning with removing dangerous chemicals from everyday products. Since the sources of pollution are numerous, everyone needs to play a part — from cleaning up pet wastes to properly using of household chemicals to reducing the use of lawn and garden pesticides. (Those who don’t subscribe to the Kitsap Sun may still find value in the graphics on the Freshwater Quality page.)

I led off the first story by showing the increased efforts by city and county governments to better manage their stormwater systems, such as pumping out their catch basins, sweeping their streets and converting outdated stormwater ponds into filtration systems, commonly known as “rain gardens.”

I also introduced readers to the Washington Stormwater Center, a research facility in Puyallup where scientists are testing the effectiveness of rain gardens and pervious pavement. Jenifer McIntyre, a Washington State University researcher, has demonstrated that stormwater from highway runoff is 100 percent effective at killing adult coho salmon. Yet that same stormwater filtered through soil — such as in a rain garden — is cleaned up enough that fish can survive, apparently unaffected.

Monday’s story addressed the increasing use of benthic invertebrates — water bugs — to measure the health of streams. The bugs are doing double duty, since they are both a measurement of stream quality and a critical part of the food web for the freshwater ecosystem.

Some 27 local governments and organizations are involved in collecting data on benthic invertebrates from about 850 stream locations throughout Puget Sound. For results, check out Puget Sound Stream Benthos.

When I began this project on freshwater quality several weeks ago, I thought it was going to be easier than some of the other story packages I have done, such as on fish, birds and marine mammals. If anything, this issue is more complex. I’ll admit that I’ve neglected this blog while pursuing these issues, and soon I will be moving into the issue of freshwater quantity.

Overall, I must say that I’ve been impressed by the many people dedicated to finding answers to the mysterious problems brought on by pollution and by those finding solutions even before the questions are fully identified.

Amusing Monday: Celebrating Alvin’s animals

This year is the 50th anniversary of Alvin, a deep-sea vehicle that has made some incredible scientific discoveries over the past half-century.

The latest issue of Oceanus magazine is a special edition that takes us through the history of Alvin, including its part in locating a lost hydrogen bomb, investigating the Deepwater Horizon oil spill and documenting the remains of the Titanic.

Read “The Once & Future Alvin,” Oceanus Summer 2014.

What really drew my attention to this issue is a photo feature called “Alvin’s Animals.” It was posted as a slide show in the online version of Oceanus. It registered high on my amusing meter, and I encourage you to click through the buttons that take you from one odd-looking creature to the next.

One of Alvin’s most significant discoveries came in 1977, when the submersible traveled to the Galapagos Rift, a deep-water area where volcanic activity had been detected. Scientists had speculated that steaming underwater vents were releasing chemicals into the ocean water. They got to see that, but what they discovered was much more: a collection of unique clams, worms and mussels thriving without sunlight.

These were lifeforms in which bacteria played a central role at the base of a food web that derives its energy from chemicals and not photosynthesis.

Since then, other deep-sea communities have been discovered and documented throughout the world, with hundreds of new species examined and named.

The Oceanus article also describes in some detail the just-completed renovation that has given Alvin new capabilities. The people responsible for various aspects of the make-over are interviewed in this special edition.

The first video on this page is by Woods Hole Oceanographic Institution celebrating Alvin’s 50th birthday. The second is a walk-around the newly renovated craft by Jim Motavalli, who usually writes about ecologically friendly automobiles.