Surf Sense Trip to South Brighton

Today, in a cold southerly wind, Rooms 13 and half of Room 11 went to the South Brighton Surf Club to learn about safety at the beach. We learnt about safe swimming between the flags, slip, slop and slap, how to identify rips and what to do if you got caught in one. In the afternoon some children were dressed as lifeguards and had to "save" some people who were caught in a rip.
A sand castle building competition was held where Seamus, Isabella G and Neo won first prize, The "Trump Towers" made by Connor, Daniel and Ben were second and Jayden, Tai and Frank were third with a sand castle body.  Most children braved a swim in the sea in the afternoon, although a brief one.
Some photos of our day are below.

Don't pollute our rivers. Save the whitebait.

Josh, Fergus and Neo made this video and devised all the little rhymes. The children in our team are keen to stop river pollution so the fish and creatures in the river, particularly the whitebait, don't have a polluted environment.Well done boys.

Stop Cows Polluting Rivers

Seamus and Priya made this video to get the message across to farmers.

Whaka Inanga

Last week Navigators 11, 12 and 13 went down to the Heathcote River to study the spawning grounds for whitebait. The children had to check the habitat where the whitebait lay their eggs. Some factors needed for ideal whitebait egg conditions were the slope of the bank, height of the grasses there and the density of the roots of the plants. Our children were great scientists and measured and checked all the criteria needed.

Michele McConnochie - Author Visit

Today we had a visit from Michele Clark McConnochie, author of the Sabrina Summers series. She kindly donated the series of books to our library.

The Whitebait are running!!

We have had an injection of whitebait into our tank and at this stage they are surviving well. They are swimming in a school and are facing the current in the tank. They are great to watch.

Whitebait Frenzy

There are  actually 6 whitebait in the tank and they are LOVING the blood worms. Mrs Dalley said they were frantically eating the worms after the weekend.

Update on our Whitebait

There are 5 whitebait still alive. Many of them found it difficult to survive the transition into our tank and died. However, the 5 hardy ones are swimming, playing and enjoying life in Navigators 12 fish tank.

Our Inanga Have Arrived

Thursday 20th October

Our 20 Inanga have arrived for us to look after for the next 5-6 weeks.

We had to check the water conditions in our tank to ensure the whitebait did not get a shock when they were transferred from the buckets from the river into our tank.

Sadly not all may survive so we need to check each day and remove any that may have died.

 We also will need to take out any that may look sick so they don’t infect the rest in the tank.

They will be fed fish flakes and blood worms alternatively at the same time each day.

There is bacteria in our tank which helps clean up wast products or any dead plant waste.

The bacteria needs to be checked so it can continue to do this important job.

The bacteria produces food for the inanga.

Oxygen is needed in the water of the tank for the fish to survive  hence the pump and air filter in our tank.

Kirsty transferred the inanga using a small net.

They seemed to have settled into their new home quite successfully.

Thursday 13th November

Environmental Investigators

White Baiting – Inanga

Kirsty came to see us. She is an environmental scientist. She spoke to us about our Inanga and we found out some very interesting facts.

Inanga is one of 5 different types of white bait. This one is mainly found in Christchurch rivers. It is the smallest of the whitebait species and they are not very good swimmers or climbers. They live from 1-3 years. When they turn 1 they become an adult

Whitebait is eaten by humans and also other animals.

Live in the sea and salt water.

Spring high tide happens once a month. Ignunga use these tides to lay their eggs.

LIFE CYCLE

Eggs are tiny and are laid on the river bank in the grasses on the roots. Keeps them safe from eels and other fish that like to eat fish eggs. The eggs are laid by the adult ingnanga there on that spring high tide. At 3-4 weeks the larvae hatch from eggs and are swept out to sea on the tides.

Larvae at sea feed on small crustaceans and grow into juveniles called whitebait. They use their sense of smell to find fresh water and swim up stream to a river.

They grow into adults in autumn. They return to salt water wedge where they meet and lay their eggs. Each adult can lay 3000 eggs. Eggs stick to grasses. Males fertilise those eggs called spawning.

So Eggs –Larvae –Whitebait – Inanga.

WHERE INANGA LIVE

As eggs they are in the salt water wedge ( love zone )

They need gentle sloping banks, grasses and shade

As larvae they live in the sea

As adults they return to the fresh water part of the river.

To lay eggs they need right mix of salt and freshwater, right tide levels, right time of year,

Inanga numbers are declining

Because if you want them around in the future they need to be looked after now.

They are the bottom of the food chain. So very important

Why They are Declining

Fish ( trout ) slugs and mice are eating them.

Their spawning habitat is changing.

Stock is damaging the river banks

Man-made changes have been happening to the banks

Lawns are getting mowed right down to the river banks affecting spawning

Excessive sediment is occurring on banks and in the rivers

Man has put in tide gates which don’t allow fish through.

 The whitebait lining up to swim up the river.

The predators chasing the whitebait