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for July, 2009.
Greetings everyone and welcome to the wonderful wide world of technology. Today we’ll take a look at the first deep space Internet, new safety monitors that would be great for Guam, and everybody’s childhood dream.
E-MAILING THE FUTURE?
Working as part of a NASA-wide team, engineers from NASA’s Jet Propulsion Laboratory, have used a software package called Disruption-Tolerant Networking, or DTN, to transmit dozens of space images to and from a NASA science spacecraft located more than 20 million miles from Earth.
NASA and Vint Cerf, a vice president at Google, Inc, partnered 10 years ago to develop this software protocol. DTN sends information using a method that differs from the normal Internet’s Transmission-Control Protocol/Internet Protocol, or TCP/IP communication suite, which Cerf co-designed.
If you want to surf the Net in space, your connection has to be robust enough to handle delays, disruptions and disconnections in space. Glitches can happen when a spacecraft moves behind a planet, or when solar storms and long communication delays occur. The delay in sending or receiving data from Mars, for instance, takes between three-and-a-half to 20 minutes at the speed of light, depending on where Earth & Mars are in their orbits.
Unlike current Internet protocols, DTN doesn’t assume a continuous end-to-end connection. If the destination path can’t be found, the data packets aren’t discarded. Instead, each network node keeps custody of the information until it can safely communicate with another node. This store-and-forward method means that information won’t get lost even when no immediate path to the destination exists. Eventually, the information is delivered to the end user.
Data were transmitted using NASA’s Deep Space Network in demonstrations occurring twice a week. Engineers use NASA’s Epoxi spacecraft as a Mars data-relay orbiter. Epoxi is on a mission to encounter Comet Hartley 2 in two years.
There are 10 nodes on this early interplanetary network. One is the Epoxi spacecraft itself and the other nine, which are on the ground at JPL, simulate Mars landers, orbiters and ground mission-operations centers.
The month-long experiment was the first in a series of planned demonstrations to showcase the technology for use on a variety of upcoming space missions. In the next round of testing, a NASA-wide demonstration will use the new DTN software loaded on board the International Space Station.
In the next few years, the Interplanetary Internet could enable many new types of space missions. Complex missions involving multiple landed, mobile and orbiting spacecraft will be far easier to support through the use of the Interplanetary Internet. It could also ensure reliable communications for astronauts on the surface of the Moon.
E-mail from the Moon! I can’t wait!
Artist concept of Interplanetary Internet. (Credit: NASA/JPL)
I live in the lovely village of Yona, just south of Ylig River Bridge. This may not mean a whole lot to you folks who live up north and don’t have to deal with bridges, but when there was a serious problem with the Ylig River Bridge a couple of years ago, it disrupted my whole life.
I work in Mangilao and had to drive to Santa Rita to get to work. Not only was it MUCH longer, I had to contend with Cross-Island Road and its murderous potholes. (That’s not poetic license. A large pothole not far from my house caused the death of a motorcyclist who, unaware of its presence, hit it at speed. As of this writing, it’s still there and not filled in.)
So anything that could make our bridges safer certainly attracts my attention. Also be aware that the following article comes from mainland US sources. Are ours inspected every two years? I know at least two of our bridges down south were built in the ‘80’s and the ‘90’s (the Talofofo Bay bridge and the Pago Bay bridge). Do they have monitoring devices built in? Maybe someone who knows will read this and enlighten us!
MONITORING THE BRIDGE
Today, humans perform visual inspections every two years of most of the nation’s older bridges. But a scarcity of inspectors and tens of thousands of bridges has put the whole monitoring system in jeopardy. While newer bridges have monitoring devices already incorporated into their design, there are thousands of bridges erected during the 1960s and ’70s that must be visually monitored.
To address the issue, a team of University of Miami College of Engineering researchers have designed a self-powered monitoring system for bridges that can continuously check their condition using wireless sensors that "harvest" power from structural vibration and wind energy.
The researchers plan to place these newly developed wireless sensors—some as small as a postage stamp, others no longer than a ballpoint pen—along strategic points inside the 27-year-old Long Key Bridge, in the Florida Keys and on a Northwest 103rd Street quarter-mile steel overpass that leads into Hialeah, in Florida.
The sensors record all sorts of data, from vibrations and stretching to acoustic waves and echoes emitted by flaws such as cracks. Even the alkaline levels in the concrete of the bridge supports can be measured.
The data can also be shared with other transportation departments via the Internet. They can also see the data being transmitted in real time. Once the information is analyzed, the team can form a prognosis of the bridges’ health, and should any defects be found, the decision on how to repair the structures will be made by the Florida Department of Transportation
The project is the second bridge health-monitoring study undertaken by the Florida scientists. They have also placed sensors along Miami’s Grove Isle Bridge as part of a smaller, one-year study funded by the National Science Foundation RB2C.
With the Federal Highway Administration estimating that more than 70,000 of the nation’s bridges are structurally deficient (and we thought we had trouble here on Guam!), the system the researchers have developed could be used as a national model for monitoring the structural integrity of bridges nationwide and alerting bridge owners to potential dangers.
Researchers monitor sensors along Miami’s Grove Isle Bridge. (Credit: Photographer: Richard Patterson)
And now for our last little tidbit. Dreams of flight are deep-seated in the human psyche. I talked last week about being able to fly on the Moon. But wouldn’t you like to personally fly here on Earth? Just get in the car and instead of having to go down that long hill out of Yona and then back up, just fly over Pago Bay and presto, I’m at work! They’ve been promising flying cars for years but hang on to your hat!
UP UP AND AWAY!
A prototype of what is being touted as the world’s first practical flying car took to the air for the first time earlier this year, a milestone in a project started four years ago by students in MIT’s Department of Aeronautics and Astronautics.
Last March, the winged car taxied down a runway in Plattsburgh, N.Y., took off, flew for 37 seconds and landed further down the runway –
a maneuver it would repeat about a half dozen times over the next two days. In the coming months the company, called Terrafugia, will test the plane in a series of ever-longer flights and a variety of maneuvers to learn about its handling characteristics.
Aviation enthusiasts have spent nearly a century pursuing the dream of a flying car, but the broader public has tended to view the idea as something of a novelty. But the Federal Aviation Administration has created a new class of plane — Light Sport Aircraft — and a new license category just for pilots of such craft, including Terrafugia’s two-seater Transition ‘car/plane’. The "sport pilot" license required to fly the Transition takes only about 20 hours of training time, about half that required to earn a regular pilot’s license.
The street-legal Transition is powered on land and in the air by a recently developed 100 hp engine that gets 30 mpg on the highway using regular unleaded gasoline. As a plane, its 20-gallon tank gives it a 450-mile range with a 115 mph cruising speed. The pilot can switch from one mode to the other from the driver’s seat, simultaneously folding up the wings and shifting the engine power from the rear-mounted propeller to the front wheels in about 30 seconds.
The vehicle may also lead to improved safety. One of the largest causes of aircraft accidents is a pilot flying into bad weather. With the Transition, a pilot who spotted bad weather ahead could simply land at the nearest airport, fold up the wings, drive through the weather on local roads, and take off from another airport once past the storm.
The full-sized version will be followed later this year by a production prototype. The company is taking deposits now and hopes to start delivering its first Transitions — or "roadable planes," as the company calls them — in late 2011.
The Terrafugia Transition flying in formation with the chase aircraft. (Credit: Photo courtesy / Terrafugia)
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Happy Liberation Day! Well, there is certainly some big space news this week. Of course, the biggest is the 40th anniversary of a human’s first step on another world. Did you really think it would take over 40 years for us to go back again? I figured there would be colonies on the Moon by now.
It wouldn’t be hard to do, you know. The Moon is covered with rilles, long narrow channels that look like the beds of dried-up rivers. But they weren’t made by water, they were made by lava. The lava flowed so near the surface that the tops of the lava channels collapsed.
Anyone who’s familiar with the lava tubes on the big island of Hawaii knows that the top of a lava tube doesn’t necessarily collapse. The long round tunnels go for miles under Hawaii’s volcanoes.
So, you go to the Moon and you use sonic sensing to locate a rille whose top has not collapsed. You drill an opening into the top and fashion yourself an airlock. Then you go down the tunnel an appropriate distance and build an airtight concrete wall. Then you fill the space with air. Bingo! Instant colony space!
There are other advantages to this scenario. The Moon has no air to protect it from the direct radiation of the Sun. In the daytime on the Moon, the temperatures rise to +250 degrees. That’s the reason the Apollo astronauts had to carry air conditioners around on their backs.
But we’ve never visited the Moon at night because during the Moon’s two-week long night, the temperatures fall to –250 degrees. They just didn’t want to have to deal with both extremes for long periods.
But here’s the interesting part; the temperature of any underground space anywhere is the average temperature on the ground above it. That’s the reason that spelunking on Guam (where there are lots of caves) is not perhaps the most comfortable sport.
Our temperate-zone ancestors all lived in caves for this reason. If you live in a place that routinely gets down to below zero in the winter and around 80 or 90 degrees in the summer, the average temperature in a cave is around 50 degrees. This means that the cave is wonderfully cool in the summer and life-savingly warm in the winter. No wonder we all lived in caves!
Here on Guam, the average temperature is 82 degrees and if you go crawling around in a cave where there is no wind for any length of time, you get pretty hot and damp.
Now if we return to the Moon, with its +250 degree days and –250 degree nights, it’s pretty easy to see that the temperature of any underground cavern on the Moon is going to be around zero degrees. Heating the space to a comfortable temperature for us humans wouldn’t be a problem at all! And it’s certainly easier to deal with than a 500-degree temperature range!
The walls of the cavern would be sealed to help prevent air leakage and an elaborate cleaning system could be built into the airlock to deal with the fine Moon dust that caused the Apollo astronauts so many problems.
So . . . why would we return to the Moon? Why did we go in the first place? Well, the answer to the second question is pretty easy. We were at war. They didn’t call it the space race for nothing. The Russians had declared that they were going to the Moon and we weren’t about to let them get there first.
So, we instituted a bold new space program that incidentally pumped an incredible amount of money into the economy. I remember that my uncle complained bitterly about all that money they were wasting to send a man to the Moon. And I said “But Uncle Dean, the money didn’t go to the Moon. It all stayed right here to pay the people that worked on all the projects.” And it did! The marvelous thing about a vigorous space program is that it bumps exactly the same firms and businesses and is as good for the economy as a war, but its main purpose isn’t to kill people!
So we went to the Moon the first time mainly to keep the Russians from getting there first. So, why should we go back?
Well, it looks like it’s war again, unfortunately. The Chinese have announced their intention to put a Chinese astronaut on the Moon, and once again, our government apparently isn’t going to let that pass by unchallenged.
But that’s NOT the best reason to return to the Moon. I keep hoping that someone will figure out something extremely important. The Moon is smaller than the Earth!
Hah! you say. EVERYBODY knows that! But what they may not realize are some very important physics facts. The Moon is not made of green cheese, but it is made of matter like rocks & dirt just like the Earth, so it has mass. And here’s the important physics fact: Gravity is a function of mass. The more mass you contain the more gravity you have.
Most people don’t realize that since you are made of matter and have mass, you, personally have your very own gravity field. It is very, very small, because in the cosmic scheme of things, you don’t have much mass.
The Earth is bigger than the Moon and it contains more mass. The Moon has one-sixth the Earth’s mass. So, why should we care?
Because if the Moon has one-sixth the Earth’s mass, it produces one-sixth the Earth’s gravity. How much do you weigh? No, don’t tell me, just divide your weight by six and that’s how much you would weigh on the Moon. You, big guy, with the ripped muscles, you say you weigh 180 pounds? You’d weigh 30 pounds on the Moon. You, lovely lady, you say you weigh 120 pounds? You’d weigh 20 pounds on the Moon.
And if that’s all you weigh, in a cavern full of Earth-normal air pressure, YOU could strap on a pair of wings and FLY! All by yourself with no airplanes or jet packs or anything else. YOU could flap your arms, take off and FLY!
And THAT’S why we need to go back to the Moon. Not for war, not for science, not for mining or any of the other myriad reasons the scientists like to cite. We need to go back for TOURISM, because YOU want to fly!
I’m ready! When does the rocket leave?
SOLAR ECLIPSE TOMORROW
The Moon is also making big news over a large portion of the Earth tomorrow because it’s going to pass directly between the Sun & the Earth. I enjoy living on Guam because periodically the government of Guam holds a fireworks display for my birthday. When I tell you that my birthday is tomorrow, you’ll probably realize why they’re so kind to me! (Hint: It sometimes rains on the 21st).
This year is a whole new ball game. This year it isn’t just the government of Guam that’s celebrating my birthday; it’s the whole solar system. Well, at least the Sun and the Moon. There’s going to be a solar eclipse tomorrow and you’re all invited to the party. The sun will be about 75% covered by the Moon here on Guam, and the eclipse will occur at lunchtime. Celebrate my birthday this year by safely looking at the eclipse!
Around noon on Wednesday 22 July, the people of the western Pacific will see a partial eclipse of the Sun. For over two and a half hours, the invisible Moon will glide eastward in front of the Sun, blocking out from half to all the Sun depending on your location. This is a total eclipse and because the Moon just happens to be at perigee, its closest approach to Earth for the month, it’s the longest eclipse of the 21st century. Totality will last over six minutes in some places. There won’t be a longer total solar eclipse until the year 2132.
The path of totality starts over India, travels over mainland China and exits the mainland near Shanghai. It then passes through the Ryuku Islands of southern Japan. It passes north of the Marianas Islands, through the Bonins and the Marshalls and ends northeast of American Samoa. No part of the Marianas Islands or the Federated States of Micronesia will experience tota
lity. On Guam, this is a luncheon eclipse. The Moon will contact the Sun’s edge at 11:25 a.m. and maximum coverage will occur at 12:53 p.m. At 2:15 the Moon’s shadow will leave the face of the Sun. On Guam and Saipan, about 75% of the Sun will be covered at maximum eclipse.
Because 25% of the Sun’s light will still be visible, this is a very dangerous solar eclipse. Even when it’s partially eclipsed, the Sun is still 400,000 times brighter than the full Moon. If you look at the Sun without protection, your eye lens focuses this intense radiation on the retina, the light sensitive layer of cells at the back of the eye. It is NOT safe to view this eclipse by looking at it directly at any time from anywhere in Micronesia.
Don’t use ANYTHING to look directly at the Sun. The best way to view the eclipse is to not look at it at all. Punch a tiny hole in a thin piece of cardboard or aluminum foil. Don’t look through the hole but, instead, hold it up so that the Sun’s image is projected onto a shaded viewing sheet a few inches behind it. Holes between tree leaves also act as pinhole projectors. Tiny images of the eclipsed Sun will appear on the ground in a tree’s shadow. You can also use a mirror to shine the Sun’s reflection onto a shaded wall, but DON’T shine it into anyone’s eyes.
This is the longest solar eclipse of the 21st century for two reasons. The first is that the Moon’s orbit around the Earth is not a perfect circle. This means that the Moon’s distance from the Earth varies by about 30,000 miles in each orbit. During this eclipse, the Moon is at perigee or its closest point of approach for this orbit.
The second is that the Earth’s orbit around the Sun isn’t a perfect circle either. The Earth reached aphelion, its farthest point from the Sun for the year on the fourth of July. So the Sun is close to as far away as it gets from the Earth. When the Moon is close, it looks bigger and when the Sun is far away it looks smaller. Both these factors align to make this the longest solar eclipse until 2132.
I’ll be selling solar eclipse T-shirts for $10 at the Liberation Day parade. Look for me, buy a T-shirt, and help keep the UOG Planetarium open. If you don’t find me, just e-mail me at firstname.lastname@example.org and I’ll tell you how to get a T-shirt.
I call solar eclipses, “Watching the Dragon” because many cultures all over the world said that a dragon ate the Sun in a solar eclipse. Please watch the dragon in safety tomorrow!
My update on the revenge of the whales last week reminded me that the ‘animals’ file is bulging so follow along as we enter the wild and sometimes wacky world of animals.
STRAIGHT AS AN ARROW (OR BENT LIKE A BOW)
Our first story concerns the insect known as the froghopper. They are also called spittlebugs because they encase their young in a frothy white foam that protects them against predators.
We all know that fleas are often considered the champion leapers of the world but fleas can’t hold a candle to froghoppers. These little guys can jump more than 100 times their own body length. If I could do that, I could soar over the length of a football field and come down considerably farther out than the opposite goal post. And if I did it straight up, I could jump over most of the hotels in Tumon.
So, what’s the froghopper’s secret? New research reveals that they achieve their prowess by flexing bow-like structures between their hind legs and wings and releasing the energy in a catapult-like action.
The researchers have discovered that a froghopper stores energy by bending a paired bow-shaped part of its internal skeleton called a ‘pleural arch’. This structure is made from layers of hard cuticle and a rubbery protein called resilin. When the froghopper contracts its muscles to jump, these arches flex like a composite archery bow, and then spring back to catapult the froghopper forward with a force that can be over 400 times its body mass.
There are other similarities between the froghopper’s jumping mechanism and the design of composite bows used in archery. Pairing a rigid and an elastic material means that the skeleton of a froghopper, or an archery bow, can resist damage even if they’re bent for a long time. Froghoppers can hold their pleural arch in a bent ‘ready position’, ready to jump at a moment’s notice, and can jump repeatedly without damaging their bodies.
More often than not, we discover that Mother Nature has beaten us to the punch in our designs and inventions. Here’s to the froghopper, the champion jumper on old Mother Earth!
An adult froghopper. (Credit: Burrows et al, BMC Biology 2008)
I’m not sure if we have froghoppers here in the Marianas, but I think I’ve seen their spittle nests. We certainly don’t have the next animal subject here, but we do have a close relative which makes this story all the more interesting.
IT’S IN THE BITE
An international team of scientists led by Dr Bryan Fry from the University of Melbourne have used sophisticated medical imaging techniques to reveal that the Komodo Dragon (Varanus komodoensis) has the most complex venom glands yet described for any reptile (including snakes), and that its close extinct relative Megalania was the largest venomous animal to have lived.
"These large carnivorous reptiles are known to bite prey and release them, leaving the prey to bleed to death from the horrific wounds inflicted. We have now shown that it is the combined arsenal of the Komodo Dragon’s teeth and venom that account for their hunting prowess. The combination of this specialized bite and venom seem to minimize the dragon’s contact with its prey and this allows it to take large animals," said Dr Fry from the Department of Biochemistry and Molecular Biology.
This is in direct contrast to most information, which holds that Dragon victims die from septicemia caused by toxic bacteria living in the Dragon’s mouth. Komodo Dragons are native to Indonesia, and adult males can weigh up to 250 pounds and grow to 10 feet long. They have around 60 highly serrated teeth that are frequently replaced during their lifetime.
The researchers conducted a comprehensive study of the Komodo Dragon bite, that included using computer techniques to analyze stress in a dragon’s jaws and compare their bite strength to crocodiles. The dragons were found to have much weaker bites than crocodiles, but magnetic resonance imaging (MRI) of a preserved dragon head revealed complex venom glands and specialized serrated teeth which create deep lacerations for entry of the venom.
The researchers located and surgically removed the venom glands from a terminally ill Komodo Dragon at the Singapore Zoo, and used mass spectrometry to obtain a profile of the venom molecules. The team also analyzed which toxin genes were expressed in the dragon’s venom gland.
The venom was found to be similar to that of the Gila monster and many snakes. Its primary effect is that it’s a vasodilator. The venom causes a severe loss in blood pressure by widening blood vessels, thereby inducing shock in the victim. These findings may explain many observations that Komodo Dragon prey become still and unusually quiet soon after being bitten. The bite wounds also bleed profusely, consistent with the discovery that the venom is also rich in toxins that prolong bleeding.
The researchers also examined fossils of the Dragon’s giant extinct relative Megalania (Varanus priscus). From similarities in skull anatomy, they determined that this twenty-five foot long lizard apparently had a similar venom and bite system, making it the largest venomous animal to have ever lived.
Komodo dragons are the largest lizards in the world. (Credit: iStockphoto/Anna Yu)
And of course, we have our very own Varanus species here in the Marianas. Varanus indicus is more commonly known as the hilatai or monitor lizard. They’re also called iguanas, but these bad boys aren’t even closely related to the iguanas of the eastern Pacific. They are, however, close first cousins of the Komodo Dragon. We all know how they got their spots, but I wonder if anyone has ever looked to see if they also have venom glands?
And now a story about animals in unexpected places.
HOW CAN YOU HIDE SOMETHING THAT BIG??
Scientists have finally solved the mystery of the disappearance of the world’s second largest fish. No, it didn’t go extinct, it was just gone for six months of the year. Read on!
Researchers have recently discovered where basking sharks – the world’s second largest fish – hide out for half of every year. The discovery revises scientists’ understanding of this iconic species and highlights just how little we still know about even the largest of marine animals.
Basking sharks are commonly sighted in surface waters during summer and autumn months, but their disappearance during winter has been a great source of debate ever since an article in 1954 suggested that they hibernate on the ocean floor during this time. The researchers from Massachusetts Marine Fisheries have helped solve the mystery and completely re-defined the known distribution of this species.
They used new satellite-based tagging technology to discover that basking sharks make ocean-scale migrations through tropical waters of the Atlantic Ocean during the winter, traveling at depths of 600 to 3,000 feet. Their data show that the sharks sometimes stay at those depths for weeks or even months at a time and thus have avoided detection by humans for millennia. Basking sharks are hard to hide. They can be over 30 feet long a
nd weigh as much as seven tons.
The researchers said they were "absolutely surprised" when they first received a signal from the tagged sharks coming from the tropical waters of the western Atlantic, near the Caribbean and the Bahamas. After all, basking sharks have always been considered to be cool-water sharks, restricted to temperate regions.
Several factors make basking sharks a challenge to study. Not only do they disappear for long periods of time, they also feed exclusively on plankton. That means they aren’t at all interested in traditional fishing methods (unlike the whales of last week’s story). And even when the sharks are found closer to the ocean surface, they spend their time in the cool-temperature, plankton-rich waters that limit underwater visibility and make diving difficult.
The findings could have important implications for the conservation of basking sharks, which have shown some signs of dramatic decline in the last half century and are listed as threatened by the International Union for Conservation of Nature.
The researchers also say that their discoveries indicate the Atlantic population – and perhaps the world population – are connected and may constitute a single population. Therefore the global population of basking sharks may be even smaller than previously thought. Efforts to boost basking sharks’ numbers will therefore need to be coordinated on a global scale.
Basking shark. (Credit: Photo by Chris Gotschalk [http://www.piscoweb.org/who/techs/cgotschalk.html], courtesy of Wikimedia
And apparently the answer to “Where does the basking shark go in the winter?” is “Anywhere it wants to!” Do they hide out on the ocean bottom? No, silly, they vacation in the Bahamas! And of course, this also serves as another reminder that there is no Atlantic Ocean or Pacific Ocean or Indian Ocean. There is the World Ocean and humans would be a lot better off if we started thinking of it in that way!
A couple of years ago, The Deep column featured the following article about animals winning in the human/animal battle for a change. Please enjoy it, and then read on for an interesting update.
THE WHALE’S REVENGE
Although we humans are definitely meat eaters, we also have a soft spot for the underdog. Sometimes animals ‘get their own’ in the constant struggle between animals and humans. The cow that escapes from the slaughterhouse truck, the turkey supposedly destined for the Thanksgiving table at the White house, the NASA chimps that have grown too old to serve; they all receive their reprieves. And when wild animals get the upper hand (or the prize), we invariably cheer.
This happened to me when I read the lovely tale of the recent adventures of longline fisherman in Alaska. We’ve talked before about the terrible toll that longline fishing takes on the world’s fish populations. The lines are several miles long and if they aren’t reeled in frequently, the fish that are caught simply rot in place and die for no reason at all. But apparently, in at least some instances, that’s not what’s happening at all.
Longline fisherman in the Gulf of Alaska began to reel in their lines and discover empty hooks or hooks with heads or partially eaten fish. And that’s when they discovered that they had been “a-fishin’ for the whale” without even trying. Sperm whales, the only carnivores among the large whales, are treating their longlines as gigantic shish-kebobs; plucking lingcod, halibut and the incredibly trendy and expensive sablefish from the handy serving lines. Researchers estimate there are 90 male sperm whales feeding from longlines in the eastern Gulf of Alaska, part of the world’s largest sablefish fishery.
Killer whales in the Bering Sea and Prince William Sound also plunder longlines. And Alaska isn’t the only place it happens. Sperm whales and other toothed whales, like pilot whales, cherry-pick fish catches all over the world.
There’s also been a lot of controversy about all the noise generated by human activity on the ocean. We’ve talked about how far noise travels in the deep ocean and how it could interfere with whale communication. Well, there’s communication going on here too. Scientists have recently figured out that the sperm whales find their dinner-on-a-hook by zeroing in on the sound of the boat engines hauling the lines. But they don’t use just any engine noise. Longliners turn their engines on and off as they haul in their lines, and the on-off pattern is Morse code that spells D-I-N-N-E-R to the wily and intelligent whales.
Longline fishermen are afraid the problem will get worse as the endangered marine mammals increase in number and teach each other the techniques of fish rustling. Sperm whales were once a prime target for whalers, but scientists suspect their numbers are increasing in oceans worldwide, although there are no definitive population numbers.
In an effort to outwit the whales, some scientists have suggested that longliners fish earlier or later in the season, haul in the line without changing engine speed, or make decoy noises with the engine to draw whales to a different area. Fishermen said they will try the methods this season, but many say the large-brained whales are just too smart.
Talk about your poetic justice! I say “Hurray for the whales” and “Keep up the good work” and “Keep ringing that dinner gong, guys, you’ve got some hungry and appreciative customers!” Sometimes the underdog does win!
Keep revving those engines, mate!
Dinner is served! (Sperm whale photo courtesy NOAA Fisheries)
For decades scientists have been intrigued by the variety of sounds emitted by sperm whales, partly due to a popular theory that suggests that the sounds might contain information about the animals’ sizes. But it’s been extremely difficult to demonstrate that a sperm whale’s clicking noises can tell us about the physical characteristics of these most massive marine mammals. Now, researchers at Scripps Institution of Oceanography at UC San Diego are unlocking some of the mysteries of sperm whale sound production.
In a paper published in the May issue of the Journal of the Acoustical Society of America, Delphine Mathias and Aaron Thode of Scripps Oceanography describe for the first time, a direct comparison between the clicking sounds a sperm whale makes and the physical features of the animal’s head, including its size and internal organ structure. The study may prove to be the first step in a new approach for investigating how marine mammals make sounds. This, in turn, may allow their numbers to be more accurately counted.
The roots of this unique study began several years ago in Alaska, when sperm whales developed the ability to steal black cod and other fish from longlines. As was reported in the previous article, the frustrated fishermen began to realize that their longline fishing boats were attracting groups of whales—which typically forage alone— to their longlines, somehow alerting the animals like a dinner bell.
To help fishermen and scientists better understand this behavior, Scripps researchers deployed acoustic recorders on longlines to help identify the sounds that attract whales to the fishing vessels. They reported that it was apparently the on-off sounds of the engines that attracted the sperm whales. Encouraged by these results, the researchers added video cameras to the fishing gear. This led to some unexpected results.
The resulting video, recorded using ambient light at 300 feet, gave the fishermen a clear idea of just how the thieving whales were stealing the fish. They pluck the line at one end to jar the fish free at the other end, just like shaking apples from a tree. The video also gave scientists a chance to match the animal’s acoustics with pictures of its physical features. Sperm whales typically dive to depths from 1,000 to 6,000 feet to catch their prey. It’s DARK down there making it virtually impossible to capture the whales on video. The fact that the animals make foraging sounds at the shallow depths around the fishing vessels is the main reason the Alaska footage is so unique.
The clicks emitted by the whales are produced more rapidly as they approach their targets of interest and are among the loudest and most intense sounds produced by any animal. Their clicks can be louder than a firecracker. But until this video was made, scientists hadn’t been able to get a direct measurement of a whale’s size and the foraging sounds it makes.
The Alaska video allowed the researchers to not only match the size of the whale’s head with its acoustic signal, but allowed them to infer the size of its spermaceti organ, which produces a white, waxy substance previously used in candles and ointments, as well as the so-called ‘junk’ inside the whale’s head. The ‘junk’ is a large organ that’s believed to play a role in transmitting sound from the whale’s head.
The study may be a first step in the broader use of acoustics to help researchers get an accurate count of whale populations. Currently it’s difficult to relate the numb
er of whale sounds recorded to the number of animals present. The ability to tease individuals apart acoustically would be a big step toward solving the problem.
The researchers also hope to eventually identify an individual whale from the sounds it makes. Although we can easily tell our friends apart over the telephone, it’s been very difficult to do this with the whales.
The video also may help fishermen to reduce sperm whale encounters with their gear. Besides the fact that the wily whales are stealing the fish which is bad for the longliner’s ‘bottom line’, these encounters are potentially dangerous to both humans aboard the boats and the whales because of entanglement. If you’re familiar with the term “Nantucket Sleigh Ride”, you know what I mean!
The video recording has also encouraged the U.S. National Marine Fisheries Service to start deploying acoustic recorders during black cod surveys off the Alaskan Coast to measure the scale of the sperm whale problem.
Snapshots from the unique sperm whale video shot off Sitka, Alaska. (Credit: Scripps Institution of Oceanography, UC San Diego)
Jim is, above all, a passionate eco-humanitarian who has developed his own science talk-radio show to inform The DEEP’s listeners about such newsy topics as global warming, shark-finning and reef protection as well as to explore earth’s many underwater and space mysteries.
sailing 12,000 miles and visiting five countries Jim is back here, ready to explore the depths of the ocean to the deepest frontier, space MORE>>
Lady Pam Eastlick is an expert in both the stars
and seas as a graduate of the University of Guam Marine
Lab and the Director of the UOG Planetarium.