Hidden Unseen: 2014-10-19

Moss Balls

Moss Balls or marimo (Japanese for "ball seaweed"), also known by various names such as Cladophora ball and Lake ball, is a species of filamentous green algae named Aegagropila linnaei that grow into large green balls with a velvety appearance. These balls grow to sizes of 12 to 30 cm across, depending on where you find them. Marimos are rare and is known to occur only in Iceland, Scotland and Japan, primarily Lake Akan in Japan and Lake Mývatn in Iceland. Recently, moss balls appeared in a large numbers on Dee Why Beach, in Sydney, the first such spotting of this algae in the southern hemisphere.

Marimo doesn’t grow around a core, such as a pebble. Instead, the algal filaments grow in all directions from the centre of the ball, continuously branching and thereby laying the foundation for the spherical form. Surprisingly, the ball is green all through, although light only reaches very short distance into the ball. The chlorophyll inside the ball remains dormant in the dark, but becomes active when exposed to light if the ball breaks apart. Moss balls are found submerged in the lake’s bed where the gentle wave action frequently turns them over maintaining its spherical shape, at the same time ensuring that they can photosynthesize no matter which side is turned upwards.

Marimo in a tank in Hokkaido, Japan.

In Japan the marimo is protected and revered, and officially a natural treasure since 1920. At Lake Akan a great effort is spent on the conservation of the lake balls, that includes an annual three day marimo festival. Small hand rolled balls of free-floating filaments are sold in shops as souvenirs. Marimo is also a staple in many Japanese aquariums.

Meanwhile in Lake Myvatn, lake balls are slowly disappearing. About a decade ago, the lake balls in Lake Mývatn were two to three layers thick on the lake bottom. Today, they’re mostly gone. The disappearance is attributed to pollution caused by mining operation in the area that commenced in the 1960s. The large amount of phosphorous and nitrogen dumped into the lake have drastically increased the lake’s bacteria that feeds on those nutrients, swarming so densely that they blocked the sunlight that reached down to the lake’s bottom. With less sunlight, the algae began to die off, exposing more of the lake bottom’s loose sediment. The wind and the waves that once rolled the balls into their shape stirred the loose sediment covering the remaining algae, further depriving them of sunlight.

The marimo was given a status of protected species in Iceland in 2006, but it was already too late.

Marimo in Lake Akan.

Marimo at Dee Why Beach, Sydney.

Tanks of Marimo at the Marimo Research Island, in Lake Akan.

Marimo at Dee Why Beach, Sydney.

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Waterfall Being Blown Upstream

The Kinder Downfall, a waterfall located in Derbyshire, England, started flowing upward as intense winds from ex-Hurricane Gonzalo swept through.

The video below, captured by Rod Kirkpatrick on October 21, shows the waterfall flowing upwards as intense winds pound on the stream, making it impossible for the water to continue on course to its destination 98 feet below. Watching the waterfall is entrancing, as it almost looks like a magic trick or some grand entertaining illusion.

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Sperm Whales Found Fast Asleep at Sea

An accidental encounter with a pod of sleeping sperm whales has opened researchers’ eyes to some unknown sleep behaviours of these giant sea creatures. Counter to previous assumptions, and unlike smaller cetaceans, the whales seem to enter a period of full sleep. But they also sleep for a very limited time per day, hinting that they could be the least sleep-dependent mammals known.

A team led by Luke Rendell at the University of St Andrew’s, UK, were monitoring calls and behaviour in sperm whales (Physeter macrocephalus) off the northern Chile coast when they accidentally drifted into the middle of a pod of whales hanging vertically in the water, their noses poking out of the surface. At least two of the whales were facing the boat, but not a single animal responded.

“It was actually pretty scary. The boat had drifted into the group with its engine off [while] I was below decks making acoustic recordings,” says Rendell. “Once I saw the situation I decided the best thing to do was to try and sail our way out of the group rather than turn the engine on and have them all react.”

The researchers was almost successful, but unfortunately they nudged one of the whales on the way out. “We had no idea how they would react; each of the animals probably weighed up to twice as much as our boat, and could have sunk us. If they had decided to take action collectively — sperm whales do engage in communal defence [against] killer whales — then we could have been in real trouble,” Rendell says. Fortunately for everyone on board, after an initial jolt of activity the whales timidly moved away, and within fifteen minutes were bobbing peacefully at the surface again.
Drifters

When the video footage from the encounter was seen by Patrick Miller, also at the University of St Andrew’s, the odd observation began to make sense.

Miller and his colleagues had earlier attached data-logging suction cups to 59 sperm whales to monitor the animals’ depth and behaviours as they travelled around the globe. They had found that the whales spent about 7% of their time drifting inactive in shallow water. What they were doing or why they were doing it had been a mystery, but seeing footage from Rendell’s experience clarified things: the whales were sleeping.

Whales and dolphins have only ever been seen allowing one brain hemisphere to rest at a time, keeping one eye open. This is presumably because they need to do important things that require physical activity, such as coming to the surface to breathe or avoid predators. They never fully let their guard down. But these observations have been strictly limited to captive environments, where brain waves can be monitored easily, and have not been conducted in the larger whales.

But now Miller, Rendell and their colleagues report in Current Biology that sperm whales seem to sleep fully while drifting, either at the surface, or at 10 metres depth1. Their naps seem to last for ten to fifteen minutes, during which time they do not breathe or move. Rendell and his crew couldn’t tell whether the sperm whales in this encounter had one eye open or not, as the whales' eyes were underwater. But the whales' total unresponsiveness leads the researchers to suspect that both eyes were closed.
Power naps

If the whales are fully asleep while in the drifting mode documented by Miller then they sleep very little: just 7% of the time. That contrasts sharply with smaller beluga and grey whales, which sleep for 32% and 41% of the time, respectively. Such a meagre amount of sleep designates the sperm whales as the least sleep-dependent mammals known. (The current record-holder is the giraffe, which sleeps for 8% of the time.)

But it is also possible that sperm whales engage in two types of sleep: full sleep while drifting at the surface, and half sleep, which has not yet been documented. “This finding raises the possibility that in the wild, cetaceans have flexibility in the type and depth of sleep that they enter, which is intriguing because this is behaviour that we have seen in birds too,” says Niels Rattenborg, a specialist in avian sleep at the Max Planck Institute for Ornithology in Seewiessen, Germany.

The limitation of the study is that it is observational. To confirm the finding, brain-wave activity needs to be measured in sperm whales in the wild. But the technology to do that is far off. “In the immediate future, we need to get a diver in the water with a camera observing the whales as they sleep, to see if they sleep with one eye open,” says Rattenborg. But such a study could be very dangerous. Although the whales are not aggressive towards humans, a slap from a startled dorsal fin would be devastating. “I’m certainly not going to be the one getting in the water with them,” says Rattenborg.

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Jharia - City of Coal Fires

Jharia and the neighbouring village of Bokapahari, in the state of Jharkhand, lie within one of India’s largest coal reserves. Coke coal is important for India’s economy as more than 70% of the country’s power supply is derived from coal. But for the 90,000 people living around Jharia, there is no benefit. Coal fires rage below the surface and noxious gases spew from fissures in and around houses. The incessant mining and the underground fire that has been burning for almost a century has contaminated everything – the soil, the water and the air. Sulfur dioxide, carbon monoxide and hydrocarbons emitted by the burning coal have caused illnesses that range from stroke to chronic pulmonary disease. Nearly everybody in Jharia is ill. Occasionally the ground collapses, swallowing buildings and people into the chasm.

Coal can ignite spontaneously at rather low temperatures when exposed to certain conditions of temperature and oxygen. This may occur naturally or the combustion process may be triggered by other causes. In Jharai, a lot of mining is done illegally in open cast mines. Here coal is mined in right next to the houses, on the streets, on railway lines, and in the station itself. Ever since coal mines were nationalized in 1971, the villagers have been eking out a living pilfering coal they sell in the local market.

Conventionally after open cast mining, areas are refilled with sand and water so that the land can be cultivated again. This has never happened in Jharia, which lead to the coal seams coming into contact with oxygen and catching fire. Once a coal seam catches fire, and efforts to stop it an early stage fail, it may continue to burn for tens to hundreds of years, depending primarily on the availability of coal and oxygen. Jharia’s fires were first detected in 1916, and were caused primarily because of improperly decommissioned abandoned mines. Since then, a huge subterranean fire and more than 70 above ground fires have consumed about 41 million tons of coking coal, worth billions of dollars, not to mention the huge amount of greenhouse gases released to the air.

It is estimated that close to 1.5 billion tons of coal are inaccessible due to the fires burning. Jharia will continue to burn until effective fire prevention and extinguishment procedures are developed and employed or the coal burns itself out. But the government is nonchalant. Residents accuse the state coal company BCCL of letting the fires burn, hoping residents will leave so it can exploit the USD 12 billion worth of high-grade coking coal that sits below their land.

In 1996, the government undertook a massive relocation program to move all the residents of Jharia and surrounding fire-affected areas to Belgharia, a new settlement 8 km away. But Belgaria has no school, no medical care, no shops and no jobs. All they were promised were a measly Rs 10,000 (USD 167, in 2014 rates) in compensation and 250 days of work. No wonder, many decided to stay in Jharia despite the blazes, the smoke and the pollution.

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