Day 8: Old school CPR
By Chris La Rosa
Most of the equipment aboard the RV Investigator is high-tech and state of the art technology. The bridge is an amazing platform with cutting-edge navigational instruments. The operations room is full of sophisticated computers crunching data from advanced sensors around the ship. But there is one piece of equipment that bucks that trend and stands out as an old-fashioned, powerful work horse. The Continuous Plankton Recorder (CPR) is a sturdy, metal contraption that looks like it comes from another bygone era of scientific expeditions and that’s because it does.
The Continuous Plankton Recorder been in use since the 1930s for collecting plankton. Photo: Chris La Rosa.
The device has been in use since the 1930s collecting plankton around the world and hasn’t changed much in all those years. We have been towing a CPR unit behind the ship intermittently throughout this voyage. Research scientists ready the CPR by preparing and inserting a cassette containing the silk filter material that traps the plankton. This can be a tricky exercise, as the cassette can be quite temperamental and refuse to slide in as it should. But with patience and steady hands, the team have managed to get it in place every time thus far.
Retrieval of the CPR from the water is undertaken by the ship’s crew. Photo: Chris La Rosa.
Launching and retrieving the CPR from the water is done by the ship’s crew. Using the large A-frame at the stern of the ship, they hoist the 85 kg device high into the air and then out over the water before lowering it. It looks like dangerous work but the deck crew moves confidently and safely as we watch from a distance. Then we simply tow the CPR until it either runs out of filter silk or the ship needs to stop in order to conduct other scientific investigations. All the while it is collecting plankton that will be analysed at a later date by researchers in laboratories elsewhere.
Researcher reviews the cassette containing the silk filter material that has trapped the plankton. Photo: Chris La Rosa.
This method of collecting plankton has been used for decades all around the world and has led to an incredible collection of information related to these tiny yet incredibly important organisms. All this hard work from such a reliable and old school looking device – the Continuous Plankton Recorder (CPR).
Before starting the voyage, the project team learnt how to use the CPR. Photo: Chris La Rosa.
Before starting the voyage, the project team learnt how to use the CPR. Photo: Chris La Rosa.
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