Warm days have come to St. Petersburg finally, in the middle of the summer. And now it's time to unleash the crayfish working at the purification facilities of "Vodokanal"
The Australian ones have replaced our local river crawfish, to save their brothers from stress. This year the live indicators went off schedule. Alexander Burenin reports on the hard work done by crayfish
Alexander Burenin, reporter: "The purification facilities have a serious system to control the condition of the water. That's why six crayfish from Australia and local rivers, who work in shifts replacing one another – are a symbol of this place. But an important symbol too. And today foreign employees have started their work
Pure water, pure heart. The level of pollution is detected by the crayfish’s heartbeat. If all six of them become nervous, this means the system of filtering has a problem. And it's time to ring the alarm.
The water temperature in the summer rises up to 30°. For domestic crayfish this means stress. The heart reacts even in clean water. That's why Australian ones are put into water. They are in different to heat. Although this year, the ecological shift came too late
Svetlana Sladkova, St. Petersburg's research center of ecologic safety: "The change of crayfish happens twice a year. The local ones start working in October, and in May we usually replace them. But this year, because of untypically cold summer, the shift was delayed by two months".
The heart of the crayfish is connected to its shell. That's where a special monitor is attached. It's data is transmitted to the control center. It is rarely a matter of concern, but sometimes certain sensitive creatures can lead to malfunctions.
So where do crayfish spend their winters? The local ones go on vacation to a lab, but in essence it's like a sanatorium. Up until the winter they can relax their claws and calm their hearts, so that they don’t generate empty concerns. They will come back to work in November, unless the winter doesn't happen as late as the summer did.