We teamed up with Ryley from Sustainable Coastlines once again to undertake a cleanup of the Tamaki Estuary. This stretch of water has been identified as one of the dirtiest in Auckland. On arriving there you wouldn't have believed it. On a beautiful day, the waterway looked clean and inviting so we were a little worried that we might not find any rubbish at all.
How wrong we were! In 1 hour, in one small bay, we managed to fill four 50L bags with rubbish. We found glass, bricks, someone's dinner plate, a door mat, rolls of sticky tape, discarded bags of dog poo (What's the point of going to the effort of picking it up and wrapping it in plastic just to leave it there???) and so many plastic bottletops. This was exciting for us because we had been learning about how plastics photo-degrade. We actually found evidence of this. See the video below:
What was really concerning though was just how much evidence we were finding. This plastic must have been in the waterway for at least 6 years for it to have photodegraded like this. The bigger problem that this causes is that when it shatters, the tiny pieces look like food to many marine animals.
We also found nurdles - small plastic pellets that are the base product of most plastic items. These tiny pellets look just like fish eggs and make a toxic meal for a hungry fish. Around the high-tide mark, we found hundreds. Apparently they enter the river as waste from the plastic processing factories that line the river.
Nurdles with paper clip for size comparison
After stopping for morning tea, we cleaned a second bay and ended up with eight bags of rubbish. We could have gone on for much longer - there was so much that we just had to leave behind as we ran out of time. It really does make you think about where our rubbish ends up. One of the best spots for us was near the stormwater outlet - so much of our rubbish enters the waterway here. That was really obvious to us!
In the afternoon, we did some activities on the beach. Each group marked out one square metre and sampled the various organic and inorganic items in our area. We are hoping to use this data to be able to make an estimate of how much rubbish is washing up on our beaches.
Ryley commented and said,
"It was a pleasure working with a group of students that showed such genuine enthusiasm and interest in learning about coastal protection."
Room 20 and Room 22 should be very proud of the contribution they have made to marine conservation. We walked the walk!
P.S. This weekend, on Saturday 21 September, is International Coastal Clean-Up Day. What will you do to help?
