Open Slideshow. The Video Plankton Recorder VPR is an underwater video microscope that images plankton and particles in the water as the instrument is towed behind ships. The VPRII system automatically identifies plankton from microns to 3 centimeters in size and displays patterns of how they are distributed in the ocean in real time. Trichodesmium are a type of colonial bacteria that form colonies with specific shapes—this one is a "bowtie. They are important to the ocean ecosystem because they have the ability to convert inorganic nitrogen into organic forms that essential nutrients for other organisms.
Copepods are tiny flea-sized crustaceans that are possibly the most abundant animals on Earth. They eat algae and other tiny prey, form large aggregations, and are a critical food supply for fish larvae and other animals, including whales. This star-shaped, single-celled organism is an acantharian. They live in the subtropical and tropical open ocean. They often contain algae that provide their nutrition, but they also consume microbes and other small plankton. They extend protoplasm along their radiating spines to catch food. This tiny but abundant crustacean is a copepod called Pseudocalanus , photographed in the North Atlantic.
Its red gut and organs are visible through its transparent covering, or exoskeleton. A shrimp-like krill, about an inch long, swims upward through the frame.
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Krill are common ocean crustaceans that are vital in ocean food chains. Unlike nets, the VPR can record and sample fragile species such as Aeginura grimaldi without damaging them. A delicate jellyfish imaged with its tentacles spread, perhaps waiting to encounter prey. Clams and other bivalves produce tiny planktonic larvae that drift until they settle down and become adults.
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This bivalve larva, a few hundredths of an inch long, swims using cilia—tiny hairs that beat to move the larva. Worms are common planktonic animals. This one, called an arrow-worm or chaetognath meaning "bristle-jaw" , is a voracious hunter that swims fast, attacks, and seizes copepods with sharp spines near its mouth. Species of arrow worm can reach four inches long but are usually smaller. But some samples were examined straightaway in the onboard laboratory, equipped with a whole range of imaging instruments.
To round off the proceedings the Tara's key exhibit, referred to as the "rosette" was lowered into the sea. This contraption was fitted with sample bottles for trapping water at predetermined depths and an array of sensors measuring the temperature, oxygen and salt content.
Loaded with kg of equipment, the rosette was the centre of attention each time the Tara stopped to take samples, an operation which sometimes lasted several days. Thanks to this operation, tens of thousands of test tubes filled with precious samples were collected from the field stations investigated by the Tara: sufficient to occupy the land-based scientists for years. The yacht is now being prepared for another expedition in , in the Arctic Ocean, the only part of the sea that Tara Oceans did not sample.
This article originally appeared in Le Monde. Topics Oceans. Marine life Craig Venter features. Reuse this content. Order by newest oldest recommendations. Show 25 25 50 All. Threads collapsed expanded unthreaded. They had to advance through difficult terrain to the northeast and capture the towns of Alakurtti and Kayraly Kairala. There they would meet up with the German divisions. Both divisions were supported by the 6th SS Mountain Division that advanced in the centre along the Salla — Kandalaksha road in a frontal assault against the defensive line. Further south, the Finnish 3rd Division launched an attack, the goal being to cut the Murmansk supply-lines at Loukhi and Kem.
For this the 3rd Division was split into two battlegroups. Aerial support for the offensive was provided by Luftflotte 5 and the Finnish Air Force. The Luftwaffe created a new headquarters for the operation and moved it into Finland. The Finnish air force fielded about aircraft of various types. The Soviets were less prepared.
While they anticipated a German invasion, with possible Finnish support, Stalin did not expect an attack along the entire border so early. The border was heavily fortified, but Soviet leadership was unprepared for the German attack. They were commanded by Lieutenant-General Markian Popov. During the first weeks the Axis would have a numerical superiority, as the Soviets only had , men north of Lake Ladoga along the border. The Axis had air superiority as Soviet Karelian was protected by the 1st and 55th Mixed Air Divisions, totaling aircraft, many outclassed by their enemy.
The Wing was tasked with providing Hawker Hurricane aircraft and training for the Russians, but also flew sorties over the Murmansk area, accounting for 14 German aircraft kills. On September 1 of Finland signed a treaty allowing the Germans to transit troops through Finland to Norway.
German aircraft used Finnish air bases, and the army launched Operation Reindeer which captured Petsamo. Despite these actions the Finnish government insisted it was neutral, but the Soviet leadership already viewed Finland as Germany's ally.
The Murmansk Oblast declared a state of emergency, mobilizing 50, soldiers and sailors. Conscripts and volunteers joined the newly formed 1st Polar Rifle Division , while sailors from the Northern Fleet enlisted in a marine infantry brigade. Civilians were also employed in the construction of four lines of fortifications, between Zapadnaya Litsa and Kola Bay.
The Soviets proceeded to launch an air raid on 25 June, bombing all major Finnish cities and industrial centers including Helsinki, Turku and Lahti. During a night session, the Finnish parliament voted to go to war against the Soviet Union and Operation Arctic Fox would begin within a week. Arctic Fox began at midnight 1 July , when the Finnish 6th Division crossed the border. Soviet positions were heavily fortified and manned by divisions from the Soviet 14th Army: the nd Rifle Division , the th Rifle Division , and the 1st Tank Division commanded by Valerian A.
Operation Frankton - Wikipedia
In daylight, facing Soviet resistance, both divisions sustained heavy losses and the attack failed,    with SS Nord Division faring especially badly. The situation worsened the next day when, after a renewed assault, the Soviets counterattacked. This failure prompted the German command to rethink its strategy. To reinforce the troops and replace the losses, additional personnel were transferred from the rd Infantry Division based in Southern Finland.
With a combined effort by all the German forces, extensive air-support by Luftflotte 5 , as well as a supportive flanking attack by the Finnish 6th Division, they finally broke through the Soviet defenses on 6 July and captured Salla. A heavy Soviet counterattack drove them back out of the town but on 8 July, a general Soviet retreat of the nd Rifle Division allowed the German forces to recapture the town.
The Soviet troops had to leave most of their artillery behind and in the heavy fighting some 50 Soviet tanks were destroyed. Meanwhile, the Finnish 6th Division was making good progress in its flanking manoeuvre to the east to circumvent Kayraly and Lape Apa. On 9 July, the th Division reached the town of Kayraly, but was thrown back by strong Soviet counterattacks. All three Soviet divisions now formed a formidable defense line around Kayraly, incorporating the adjacent lakes Apa and Kuola into their defense.
The German advance stalled, facing difficulties with arctic forest fighting. At the same time the Soviets managed to bring additional reinforcements to replace their losses. Feige relented and on 27 and 29 July the corps made two additional attacks separately against the Soviets which led to nothing. Due the grim situation, and mounting losses 5, men in just one month , AOK Norwegen finally ordered Feige to halt the offensive.
Beginning on 30 July, the Finns succeeded in smuggling a battalion over the lakes, behind Soviet lines, which allowed them to flank and subsequently defeat the Soviets on the other side of the canal. On 7 August, the Finns captured Kestenga after fierce fighting. Reacting to the Finnish advance on the Murmansk railway, the Soviets transferred additional troops the 88th Rifle Division as well as the independent Grivnik brigade into the region.
Soviet resistance now stiffened, leading to a stall of Group J's advance east of Kestenga. They broke through the defense line at the Yeldanka Lake , and were able to come within a few miles short of Ukhta proper. However, the new Soviet reinforcements prevented any further gains, and the Finnish attack stalled in this sector too. With the increasing Soviet resistance, a plan was made to concentrate on only one target. It was decided to halt the Ukhta-offensive and instead support the advance east of Kestenga in mid-August. This new drive was able to make some ground in the arctic no-man's land, but no decisive breakthrough could be achieved.
The increasing Soviet activity also worried Siilasvuo, especially as Group F was now standing still in exposed terrain, open to a possible Soviet encirclement. To counter this, AOK Norwegen decided to bolster the Finnish forces for a final push to the east and the rest of the SS Nord division was moved south and put under Finnish command. Once the reorganisation had been completed, a new, final attack had to be launched by both Finnish battlegroups in October.