Our Inquiry into sea creatures has included exploring the lifecycles of creatures like jellyfish and pāua. Many of these creatures go through a larval stage. During this time, they are plankton. We have also explored how some of the biggest creatures on the planet, baleen whales, feed by collecting tiny plankton.
In fact, it has become clear to us that plankton may be tiny, but it's a pretty important part of our marine environment.
Time to find out more and take a look at some local plankton! Luckily, our Senior students have for a number of years been part of a project called Moana Mana. This has allowed them to build up a wealth of knowledge around observing and monitoring the health of our marine environment. During beach week, and at other regular times throughout the year, they can be found down at Worser Bay Boat Club, working with experts to survey the ocean and the creatures that live there. This has including taking plankton samples to view under microscopes in order to survey the creatures they find.
On Tuesday afternoon, we headed down the track to the beach.
On arrival, our first job was to collect some plankton. This is done by dragging a fine-gauge net through the sea.
The plankton collects at the bottom of the net.
John showed us how the cap at the bottom of the net is unscrewed and the plankton tipped into a container with a small amount of water. It is usually possible to see some very tiny creatures zipping around in the jar and also some green slimy stuff which is mainly phytoplankton (small algae and plants). Zooplankton is the name for the animal part of plankton, like larvae and fish babies.
Now, it was time to take our container of plankton back to the boat club classroom for analysis.
We put a few drops of plankton onto some petri dishes, placed them under the microscopes and focussed in. We quickly began to find creatures!
We had a plankton identification guide and some photos on hand to help us to figure out what we were looking at. Crustaceans of various kinds, jellyfish larva, salps and very small jellyfish were all visible.
We also saw plenty of phytoplankton: the green slime looks pretty under the microscope.
This was a cat's eye under the microscope: not plankton, but pretty interesting to look at, all the same.
Thanks so much to our big buddies in Māhutonga and Matariki for hosting us and sharing your knowledge and giving us a whole new perspective on the ocean near our school.
When we got back to school we looked at some of the pictures of plankton and had a go at sketching the details of the microscopic sea creatures.