29 December 2010

21 December 2010

SOLSTICE



Iridescence Sea. Mark Yankus.

VLF in Finland from Jean-Pierre Aube on Vimeo.

According to its Vimeo page, this video was shot on the December solstice in Jerisjarvi, Finland:
 
Shoot on a frozen lake in the darkness of the polar nights the video is a 11 minute scan of the horizon. Recorded simultaneously the sound track is a recording of Natural Radio. I was looking for Auroral Chorus an obscure electromagnetic phenomena link with northern lights. On the video you can also hear dawn chorus generated by a big solar storm and military telecommunications from Russian submarines beacons.

20 December 2010

LINGCOD LINGO

Lingcod. Photo by Jim Lyle at DiveBums. This site hosts a wealth of photo beauties, worth an extended visit.
A new paper in PLoS ONE reports the whereabouts of tagged lingcod in Alaskan waters over the course of 16 months. Several aspects of this research are interesting.

First up, lingcod (Ophiodon elongatus) are large bottom-dwelling fish up to five feet long and 130 pounds, who live at least 20 years. They inhabit only the kelp forests, rocky shorelines, and tidal inlets of the Northeast Pacific from Mexico to Alaska. 

Range map of lingcod. Image credit: Mmm courtesy Wikimedia Commons.
The males are nest-guarders who move into shallow waters to defend territories prior to spawning. This leaves the species highly susceptible to overfishing, since the males are tied to the nest in inshore waters (read: easy to catch), and since catching a male will also result in the death of all his dependent offspring. From the paper:

Lingcod... support an important recreational and commercial fishery. Currently, lingcod is a species of critical concern to fisheries managers throughout the Pacific Coast because of the combined factors of low annual productivity and susceptibility to overfishing are a result of their high site residency and association with the nearshore zone. In Canada's Strait of Georgia, the lingcod commercial fishery has been closed since 1990 while in Washington, Oregon, and California lingcod was declared an overfished species between 1999 and 2005.

So the researchers set out to see what they could learn about subpopulations of lingcod. Do they move around, do they mix, and if so where do they go at what ages and is that true for for males and females? The who-what-where-when-why-and-how of science.

The POST array in 2010.

They tapped into POST (Pacific Ocean Shelf Tracking Project), an acoustic receiver array stretching from San Francisco to Alaska. It's one of 17 projects of the Census of Marine Life that's shedding light on more than a few sea mysteries:

  • Green sturgeon in the Sacramento River swim regularly from California to British Columbia and sometimes as far as Alaska.
  • Salmon smolts swim downstream along the Columbia River and up the continental shelf to Southeast Alaska, a 2,500 kilometer/1,500 mile journey of ~3 months—roughly 25 kilometers/15 miles a day. 

That's a lot of aquatory for a smolt. 

Coho salmon smolt. Photo by Cacophony, courtesy Wikimedia Commons.
POST works with acoustic receivers anchored near the seafloor and close enough together that tagged animals swimming by are heard by at least one receiver. Thanks to the wonders of this distant listening array, revelations about lingcod life are emerging from the saltwater.

We used [POST] to monitor movements and residency of 21 acoustic-tagged lingcod for up to 16 months. Eight of sixteen lingcod (50%) initially aged at 2.5- to 3.5- years-old dispersed from their tag site. Dispersal was highly seasonal, occurring in two, five-week periods from mid-December through January and from mid-April through May. Dispersal in winter may be related to sexually immature lingcod or newly-mature male lingcod being displaced by territorial males. Spring dispersal may be indicative of the onset of migratory behavior where lingcod move out into Prince William Sound and possibly the offshore waters of the Gulf of Alaska.

From PLoS ONE.

The diagram above shows the what, where, when, how, and who of eight lingcod dispersing from their tagging areas.
 
  • a) Lingcod dispersing out of Port Gravina, spring 2009. 
  • b) Lingcod dispersing from their tagging site in spring 2009 and remaining in Port Gravina. 
  • c) Lingcod dispersing out of Port Gravina, fall 2009. 
  • d) Lingcod dispersing out of Port Gravina, winter 2009–2010. Colored lines denote individual lingcod and arrows denote direction of travel. Dashed lines indicate absences >1 d without detection. 

The tagging also revealed at least a few of the why's in lingcod life. Some left their home waters for periods up to seven days when Pacific herring migrated through—presumably in pursuit of their prey. Some fell prey to predators themselves.

Unexpectedly, our acoustic array provided accurate information on the timing and direction of a lingcod being preyed upon and removed from the study area. We were able to conclude that the predator was likely a marine mammal based on its speed, and in this case, the depth of the predator as the lingcod had a pressure sensor tag implanted.


Finally, a teaser of the lingcod's beautiful, plankton-infused world, translated into our native visual language.

The paper:

  • Bishop MA, Reynolds BF, Powers SP, 2010 An In Situ, Individual-Based Approach to Quantify Connectivity of Marine Fish: Ontogenetic Movements and Residency of Lingcod. PLoS ONE 5(12): e14267. DOI:10.1371/journal.pone.0014267

12 December 2010

THE CURIOUS FISHBLOG OF ADRIAEN COENEN

Adriaen Coenen (1514-1587) was a Dutch fishmonger, auctioneer of seafood, amateur biologist, imaginative illustrator, born storyteller, and autodidact extraordinaire. Plus he was the world's first blogger.

Well, not really. Though I was struck, browsing page by page through his Visboek (Fishbook) at the National Library of the Netherlands, by how bloglike his work was, complete with a compulsive need to share what he was learning in compartmentalized form.

One of the finest pictures in the Visboeck is the flying fish (above), a species unknown in European waters. Coenen freely borrowed from other fish books of his day. He also had the opportunity to see many strange species or hear many a fish tale from the seagoing vessels visiting his seaside town of Scheveningen.


(The Beach at Scheveningen. 1658. Adriaen van de Velde.)  

This painting above was made nearly a hundred years after Coenen. Yet the beach was probably much the same as when, late in life, Coenen conducted the town's fish auctions there.

[Disclaimer: Virtually all the information in this post is Googlemangled from the Dutch pop-ups on the National Library of the Netherlands site. I've done my best to wrestle sense into them, but I make no guarantees.]
 
Amazingly, if I'm reading this translation correctly, Coenen didn't begin his Visboek until he was 63 years old. He compiled all the information and illustrations—more than 800 pages—in only three years.

As his work became known, he began to hobnob with the well-heeled and well-schooled in The Hague, some of whom became his patrons. Fishermen and sailors helped out by bringing him strange specimens acquired from distant waters.

Early in the book, Coenen presents a series of maps in two-page spreads. The one above is of the herring catch, so important that Coenen called it "our big golden mountain in Holland." 

According to the pop-up window on this page at the National Library of the Netherlands, the technique of curing herring at sea was already at least two centuries old in Coenen's time. During his lifetime, the herring fishery moved from inland to offshore waters. 

I'm guessing this was a result of overfishing, perhaps from those same advances in curing techniques that allowed boats to stay at sea and fish longer. Or maybe it was a result of changes in climate and currents. Or both. Or neither.

One of my favorite images is of this maplike tuna caught in the Mediterranean in 1565. The fish was reported to sport tattoos or drawings of ships on its skin. This finding was so extraordinary that six witnesses recorded their observations of it with a notary public in Gibraltar.  

Coenen learned of this fish in a pamphlet he received from his patron, Cornelis Suys, President of the Court of Holland in The Hague. 
























One of the wondrous aspects of the Visboek is the way Coenen ranges bloggily all around the great tree of knowledge. In the page above, he describes the life cycle of "tree geese," or barnacles (I think).

Tree geese were curiosities dating back to at least the 12th century. They were believed to come from far northern regions and to fall somewhere between plants and animals. The best I can make of this Googlemangled passage is that the tree geese grew on trees but wouldn't come fully to life until they fell from the trees into the water. A different species, the goose barnacle, could grow right on the trunk of a tree. And a third kind could live on wood decaying in water.


































Coenen noted that lobster and crab were food mostly for the rich.


He complained that jellyfish were useless, if not worse, and wondered why nature put them into the sea, calling the phenomenon "incomprehensible to man." 

In Coenen's village of Scheveningen, the fishermen were burdened by jellyfish, which "hang from their nets as firm as glue" and had to be loosened by hand—a process that left the men numbed from repeated envenomations.















































Coenen noted that salmon were known for their great strength and endurance and that only the wealthiest citizens could afford to send fishermen to sea to catch them. Salmon nets were almost prohibitively expensive since they needed to be much stronger than those used to catch plaice, haddock, or cod.

The 16th century saw wild oscillations in salmon abundance. In Coenen's father's time, salmon was rare to find or catch, even though worth a fortune. In Coenen's youth, there was an oversupply and prices fell. Around 1580, they became scarce again and prices rose. 

The ocean sunfish, or mola mola, was a great rarity in Dutch waters. Coenen saw only three in his life. In 1562 a large zonvis (above) was caught by a local fisherman and Coenen bought the fish and (best I can tell from the translation) sent it out with a man who took it around Delft and The Hague, exhibiting it for a fee. Coenen later dried the fish and sold it to an adventurer (I'm not at all confident of anything about my interpretation of this translation).
























Coenen had never seen the fierce-looking walrus he depicted in the Visboek. He listed several other names for this animal: elephant seal, water lilies, and "a strange sea horse." The accompanying text is in German and recounts the capture of these wonderful creatures in the distant past in waters between Africa and Spain.










































































Coenen more or less quoted from the Swedish ecclesiastic and writer Olaus Magnus, whose book Historia de Gentibus Septentrionalibus (History of the Northern Peoples), described how the people of the far north employed every part of a whale. They used the skin to make belts, bags, and clothing. They used the blubber to smooth and waterproof their boats and to lubricate their wagon wheels. The smallest bones were used as fuel for warming and cooking fires. The large bones were used as building materials—the only such materials in a realm devoid of trees. From the ribs, vertebrae, and other bones, the people made whole houses, plus tables and benches. 

Olaus Magnus imagined that people living in whale-bone houses often dreamt they were in danger on the sea and that storms threatened to drown them.

























A curious new species was discovered in 1431 in the waters off Poland. It was called the zeebisschop—the sea bishop (above). Coenen sourced his information from the 1517 Great Chronicle of Holland, an authoritative work in his time. 

The zeebisschop possessed a hat, a wand, slippers, a chasuble, and gloves, just like a real bishop. It also possessed a head, eyes, nose, cheeks, mouth, arms, hands, and feet, and yet it was a cold fish. Coenen found this to be evidence of the wonderful works of God, and was inspired to write poem about it. Make what you will of the tortured translation:

The bishops are not only was
That means there are large parried
Also grows in the sea such a bishop, a serious biter 
And does he not been wearing miter.


In 1564 a sea monster appeared in Brazil. Coenen portrayed it on the bank of a river, standing on its hind feet or flippers, 17 feet long, and with a velvety skin. It uttered loud cries. 

The locals attacked and killed it with swords and bows and arrows. Was it a manatee? Or a fur seal far from home?
























The most famous and wonderful sea creatures of Coenen's time were the mermaids and mermen. He wrote pages about them but always quoting others. He remained skeptical: "But I can not find a man do this day who with his own eye in the year 1579 has seen one."

























In Coenen's time there were stories of the existence of strange fish-people something along the lines of the wolf-people we know today. He wrote of a woman found in 1403 in the Dutch town of Purmer, who swam in the sea searching for food, slept in the water, and was covered with moss and slime.

The local townswomen gathered their courage and captured this wild woman, cleaned her up, and took her to Haarlem, where she remained a curiosity for many years. Eventually she learned to eat normal food, and to spin wool, but not to speak. 

























Even in the 16th century fishing was a sport enjoyed by people who did other things for a living. Coenen wrote that "craftsmen" from the cities took pleasure in fishing in the waterways and canals, and that the inhabitants of coastal villages who were not professional fisherman still fished for fun in the summer.
























Then, as now, there seemed to be a lot of interest in sea life that might potentially eat you, such as this "Monstra in Nordwebra"—maybe a great white shark?

















 
Coenen wrote how fishermen lured whales to their boats by playing flutes, then harpooned them. 

On another page, he described how whales love "zeekalveren" (young seals), herring, and other oily fish, and how they take great risks in catching them by swimming into shallow water, where they sometimes accidentally beach. The locals considered this a great windfall and—to prevent the whales from floating free on the tide—rushed to tie them down with ropes and anchors.

Maybe this explains the rope around the tail of the sperm whale in the Jan Saenredam engraving I wrote about in an earlier post. Maybe this is what inspired Jonathon Swift's people of Lilliput?


 





















Based on the writings of Olaus Magnus, Coenen described  the process of fishing with bells and other noise. In the top image you can see a fish caught in a trap with a hanging bell. Some fish were spellbound by certain sounds, said Coenen

The lower image shows a large group of dolphins circling a boat when a fisherman played harp—a sound that "obviously dolphins love." After the performance, the dolphins beat their tails hard against the water as a token of their appreciation. However, this was seen as a bad omen, since soon thereafter a heavy storm blew up.

Here Coenen portrays a huge herd of whales that (as best I can tell) passed by the the Caps Hondsbosse seawall, leaping and breaching, in the same year William of Orange (the Dutch one not the English one) was married. The old people said: "They draw to the bride."

But Coenen wrote that gatherings of whales like this passed by Scheveningen twice a year, that they always swam in the same direction, and that it might be two or three hours before the herd had completely passed by. Almost always afterward, he said, there would come a severe storm or lightning.


Throughout his book, Adriaen Coenen describes getting his hands on interesting specimens and drying them or preserving them in some other way and hanging them outside his house. I wish he'd painted an image of that seaside museum. Sadly, there don't seem to be any surviving images of him either, at least not that I could find. He also wrote a Walvisboeck, a Whalebook. I guess these works survive as his avatars.

06 December 2010

AUTHENTIC MARINE MAMMAL

Freediving World Record - 88m without fins from william trubridge on Vimeo.

New Zealand freediving champion William Trubridge set a new world record two years ago in the Constant Weight without fins discipline. He's broken his own sequential records ever since and will be trying to best his own record again (of 95 meters/ 312 feet) in a blue hole in the Bahamas in a few days time.

What I like best about this video is the way you can see the moment when his buoyancy flips from positive to negative and he no longer has to kick to descend. On the other hand, he then has to frog-kick hard for most of the way up before he can simply float to ascend.

In his own words:

I have a relationship with the depths
they beckon me beyond my means
cold dark vacant pressure
forever night, endless dreams




(William Trubridge freediving at Dean's Blue Hole, the Bahamas.)

05 December 2010

SUNDAY POETRY: "THE DIVING APPRENTICES"
























(Photo from here.)


Sometimes you watch them going out to sea
On such a day as this, in the worst of weathers,
Their boat holding ten or a dozen of them,
In black rubber suits crouched around the engine housing,
Tanks of air, straps and hoses, and for their feet
Enormous flippers.

                                 The bow, with such a load on board,
Hammers through the whitecaps, while they talk;
Junonian girls, Praxitelean boys, pelted on
By bursting clouds, by spray, eventually heave
The tanks upon their backs, the boat drifts at anchor,

And down they go to the sea floor, by the foggy headland.
At least, you can presume they kick the flippers
And plunge to where the water is more calm. The cool
Instructors must keep eyes and ears
Open. Accidents out there, they happen.

                                        You might imagine scraps
Of cultural débris, a broken pot, a ring, a cogwheel
Come up, clutched in a palm, and interesting,
A wave pattern in it, the blade of a sword,
When a lucky diver breaks again the surface. Time,
Time and again frigate and schooner cracked
Blown against the rocks, holed below the water line.

                                        Even an inscription
Might now be coming up from those green deeps.
Yet the divers do their silent thing. On the sea floor
Expect only the sea, a multitude of sand without an hourglass.
Round somebody’s ankle idly it swarms. A diver
Hangs by a thread of breath in solitude there. Some go down
In all simplicity curious; to have tales to tell;
And who knows, what they learn
Just might, long after this, be usable.

01 December 2010

AURORA INTERNETIS


I'd like to spend a winter in the high latitudes and experience as many aurora shows as possible. Sometime in the next three years would be ideal, according to Astronomy Picture of the Day:

Auroras are occurring again with increasing frequency. With the Sun being unusually dormant recently, however, our Sun has become increasingly active and exhibiting a greater abundance of sunspots, flares, and coronal mass ejections. Solar activity like this typically expels charged particles into the Solar System, some of which may trigger Earthly auroras. As this year unfolded, the above timelapse displays of picturesque auroras were captured above Tromsø, Norway. Curtains of auroral light, usually green, flow, shimmer and dance as energetic particles fall toward the Earth and ionize air molecules high up in the Earth's atmosphere. With solar maximum still in the future, there may be opportunities to see spectacular aurora over the past three years, the amount of Sun-induced auroras has also been unusually low. More personally over the next three years.

























(Image courtesy NASA.)

This amazing composite and its explanation appeared on a 2006 Earth Observatory page:

From space, the aurora is a crown of light that circles each of Earth’s poles. The IMAGE satellite captured this view of the aurora australis (southern lights) on September 11, 2005, four days after a record-setting solar flare sent plasma—an ionized gas of protons and electrons—flying towards the Earth. The ring of light that the solar storm generated over Antarctica glows green in the ultraviolet part of the spectrum, shown in this image. The IMAGE observations of the aurora are overlaid onto NASA’s satellite-based Blue Marble image. From the Earth’s surface, the ring would appear as a curtain of light shimmering across the night sky.

Since Norway and Alaska aren't in my immediate travel future, guess I'll just have to enjoy the aurora internetis—open access at all latitudes and in all seasons. Hope you enjoy too. (Credits below.)






























































Credits, from the top:
  1. Credit: Joshua Strang, USAF, Wikipedia.
  2. Photo by well_lucio, at Flickr.  
  3. Photo by Roskifte, Thomas Roskifte, at Flickr.
  4. Photo by Soytnly, at Picassa.
  5. Photo by Samuel Blanc, courtesy Wikimedia Commons
  6. Photo by Donald R. Pettit, Expedition Six NASA ISS science officer, on board the International Space Station, courtesy NASA
  7. Credit: Image Science and Analysis Laboratory, NASA-Johnson Space Center: "The Gateway to Astronaut Photography of Earth." 
  8. Photo by Chris Danals, National Science Foundation
  9. Credit & Copyright: Dave Ewoldt (Okarche, Oklahoma), from APOD.  
  10. Photo by Akhmetsafin Ruslan,at Spaceweather.
  11. Photo by Sylvain Serre, at Spaceweather.
  12. Credit & Copyright: Ole Christian Salomonsen, at APOD.

(Aurora Borealis. 1865. Frederic Edwin Church.)

Finally, this illumination by one of my favorites, Frederic Edwin Church. The painting was apparently intended to be a metaphoric omen of the coming Civil War. From the exhibition label at the Smithsonian:

The ship and sled team in this image belonged to Frederic Church's friend, polar explorer Dr. Isaac Hayes. Hayes had led an Arctic expedition in 1860, and gave his sketches from the trip to the artist as inspiration for this painting. Hayes returned from his voyage to find the country in the thick of the Civil War, and in a rousing speech vowed that "God willing, I trust yet to carry the flag of the great Republic, with not a single star erased from its glorious Union, to the extreme northern limits of the earth." Viewers understood Church's painting of the Aurora Borealis (also known as the northern lights) as a portent of disaster, a divine omen relating to the conflict.