Thursday, 3 March 2016

Oil Spill Monitoring

Another very important job for the Scientists at Bay of Plenty Regional Council is to keep our harbour clean.
Last year in April, a terrible accident occurred.  1500 litres of oil was spilled in Tauranga harbour!
How many milk bottles is that?
How many drink bottles?
Coastal Scientist Rob Win is still checking the harbour at low tide for oil from the spill - a whole year later!
You can read the details of the spill in this Stuff article from last year.
Most of the oil floated out into the Maungatapu area of the harbour.
We waded out in the Maungatapu mud this morning and collected shellfish and sediment samples that are bagged up and then sent to the laboratory in Whakatane.  The laboratory staff will test all the samples and let Rob know if there is still any unwanted oil in this area.

You can still see the oil stains on the top edge of this retaining wall.

This is a view towards the road up from Turret Road to Welcome Bay.  The big tunnel works are happening behind the trees in the background.

Here are a couple of Titiko (sand snails) that are sitting on top of the sand at low tide.

We had to pick up quite a few at each site so that the Laboratory Technicians have enough snail meat to test for oil residue.

It got pretty muddy in some places.  

Digging for Macomona (Wedge Shell).  They live about 5cm below the surface in the black mud.  The black mud is pretty smelly.  This is because there is no oxygen in it.  Peew! 

We also collected loads of cockles which live just below the mud surface.

Just the Facts:
Cockles are filter feeders - this means they suck water and nutrients in through the gap in their shells.  They tell us whether there is oil IN the water.

Macomona are surface feeders - they suck water and nutrients from the water's surface.  
They tell us whether there is oil ON the water.

 A beautiful morning to get wet and muddy!


  1. What a beaut day to do this! Next time take some cat food with - those whelks love it and within minutes there are hundreds. :)

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