Harvesting and Handling

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Paua are extremely fragile and all care must be taken during the handling of them so that when undersized paua are returned to the reef they have the greatest chance of survival.

Paua are ancient snails that have remained unchanged since the time of the dinosaurs. Their blood and respiratory system are basic and somewhat inefficient so special care needs to be taken to avoid damage that can have dire repercussions post handling.

Paua are easily stressed by handling, noise, bright light or vibration and their defence mechanism in this situation is to clamp down. Recent research has shown that this clamping down process triggers several physiological events that can take a couple of days to get back to normal. Their heart immediately shuts down and they can reduce their blood volume with a corresponding reduction of up to 10% of their green-weight within half an hour.

Paua blood is clear in colour as it travels to the gills and light blue in colour as it travels out of the gills. Its blood circulation system is unique even compared to other shellfish species. It does not clot and there are very few restrictions (valves etc) to stop the blood draining out so even the smallest cut may result in the paua bleeding to death. In some cases the paua will attempt to stem the flow of blood by contracting the muscle around the wound while the cut heals which can restrict movement and its ability to catch. When a paua loses blood it takes an enormous amount of its energy to replace it (i.e. make new blood).

When you combine foot damage, blood loss, lack of feeding, the energy required to replace blood volume and the things that can trigger stress, it is easy to see why injury can so easily lead to death of undersized paua in the months following handling.

There are a number of ways to ensure that damage to undersized paua is minimized and you can help ensure your future paua harvests by following a few simple guidelines.