The situation for the species is not much better in Estonia, though improvements are unlikely without significant changes in land use.

Katrin Kaldma, an RMK specialist on freshwater pearl mussels, told "Terevisioon" Wednesday that despite the incident, the species will not disappear from Finland, as there were many more in the affected river.

"What has happened is that a significant stretch of pristine natural landscape was annihilated, and many individual mussels were lost," she said.

Kaldma described the incident in Finland as fortunate in one sense in that, unlike in most rivers, the mussels there can survive independently. "The impact was huge, but fortunately, the population there is large. Restoring the river is viable, but will take a very long time. If there are any positive takeaways, it's that this happened in a region which has among the world's best expertise in handling such incidents," she said.

Meanwhile in Estonia, the only native population of freshwater pearl mussels is to be found in the Pärlijõgi (literally "Pearl river"), but also known as the Pudisoo River, in Harju County.

Kaldma noted that Estonia's aquatic ecosystems are actually more strictly protected against incidents like the one which happened in Finland. Legislation states that vehicles are not allowed to drive into the water, or approach it too closely.

While this might seem like not the most eventful live-link of all time: "Our assumption was that the life seen through the nature camera would be mostly static, with nothing really happening. But when we turned on the camera, we saw that there is actually a lot of vibrant activity," Kaldma said.

Freshwater pearl mussels are a species which, according to Kaldma, have remained essentially unchanged for a hundred million years.

However, things are not going well for the freshwater pearl mussels in Estonia in recent centuries, decades and years.

Ideally, they should live in clear and clean water. The main issue, according to Kaldma, is that the rivers get filled with a lot of loose sediment.

"We have a lot of drained landscapes. With drainage, loose soil moves into bodies of water, and drainage also takes away water from the landscape. There is no consistent water flow, especially during dier periods," the expert explained.

Sand which should be moving toward the river mouth stays suspended in the water. Every flood or rain event stirs this up again.

"This is the main problem facing the freshwater pearl mussel. It is tied to their life cycle, where their young stages actively use the riverbed. Food and oxygen need to reach them, and the riverbed needs to be alive. Unfortunately, in our rivers, it is not very 'alive,' so the young tend to die, and there are no new generations coming through," Kaldma concluded.

Unfortunately, regrettable incidents still occur in Estonia. "This is not because we have bad laws; on the contrary in fact, they are good, and the enforcement processes are well-established. What tends to happen is that individuals sometimes don't realize the impact of their actions and take on responsibilities in areas where they lack competence," Kaldma said.

A new nature camera now allows people to observe the underwater world, including the lives of freshwater pearl mussels.

"The camera shows these rare creatures in their natural environment," Kaldma said (the camera is linked to Youtube and can be viewed below).

Freshwater pearl mussels as their name suggests can produce pearls, and are particularly long-lived. One species caught in the 1990s in Estonia was estimated to be over 130 years old.

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