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Henry GreenPrimary School

‘Learning Together, Learning For Life’

The caterpillar diaries

Day 1

Our caterpillars have arrived, they are very small and not moving around much yet. They are in a jar which has special food at the bottom - we can look but we must not touch them.


Day 2 - 5

The caterpillars are wriggling around the jar and eating the food. They are practising spinning thin webs and spend lots of time sleeping. As they grow, they shed pieces of their outer skin called their exoskeleton - This allows them to get bigger. You can see the old exoskeletons in the jar, they are little black pieces and they break off the tail end of the caterpillar. Our caterpillars names are - Spike, Olaf, Fuzzy, Spiky, Kiwa, Super caterpillar, Sharp caterpillar, Willy, Bubble and Rosie 



Day 6 - 10

The caterpillars have grown each day, longer and thicker! They are very active and spend their days eating and crawling around the jar. Sometimes they hang upside down in their webs or climb on top of each other. You can see their patterns becoming clearer and most have thin stripes of pale yellow and green shining through their dark, spiky outer skin. However one of our caterpillars is pale green with a black face - it will be interesting to see if he looks any different to the others as a butterfly!



Day 11-14

Our first caterpillars are ready for metamorphosis to begin! One caterpillar has finished growing and eating, he is now hanging from the top of the jar in a j shape. It is really important that we do not move the jar or disturb the caterpillars any more. The next morning, seven more are ready. When the caterpillars are fully grown, they hang themselves in a safe place off the ground and a chrysalis/cocoon develops around them. The caterpillar will spend 2 weeks inside and during that time enormous changes take place, wings will develop and a new body structure too,ready to emerge as a butterfly.

Day 15-22

Our caterpillars are all in their hardened chrysalis/cocoons and have now been moved safely to the butterfly house. Over the next 2 weeks, the chrysalis will become darker in colour and we will begin to see the wings through the thin shell. The caterpillars will now become butterflies, waiting to emerge with their soft crumpled wings. We need to watch very closely for signs that they are emerging so we can put sweet fruits and flowers in the butterfly house for them to eat.


Day 23-25

Our butterflies have begun to emerge, the butterflies nibble a hole in their cocoon and climb out, then their soft wings begin to stretch and fill with liquid called meconium - this is bright red and you might see some dripping out in the butterfly house too.  The butterflies as they get stronger, will practice opening and closing their wings and climb to the top of the butterfly house and fly back down too. 


Day 26 

The butterflies outside in nature eat sweet nectar from flowers, using their long thin tongues. In our butterfly house, we can put drops of sugar water or some mushy fruit for the butterflies to enjoy - their favourite is really old black bananas! I squished it up inside the skin then cut holes in the top for the butterflies to poke their tongue in and drink the sweet juices. You can help butterflies in your garden or outside your home by squashing up a really old black banana and cutting some slots in the skin,pop it outside and you will feed butterflies and bees for weeks!


Day 27 

The final 2 butterflies have emerged, some of the others are practising flying a lot - a sign that they are ready for release, so I headed outside and opened up the top to see if any wanted to fly away. 5 chose to fly off into the wild and the other 5 will stay for a few days longer.


Day 28-30

The remaining butterflies begin to practice flying and are soon ready to take flight. It is now time to release them, as they fly away they stop and land in the grass, on flowers and even our hands! The butterflies will lay tiny eggs on the underside of a leaf when they are ready, and the whole process will begin again. These red and black butterflies are called 'painted ladies' because of their beautiful patterns, you may see other types of butterflies outside too, While I was releasing the butterflies I saw some white and some pale blue ones flutter past, I also saw some brown moths which look very similar to butterflies too. I hope you have enjoyed learning and watching about how caterpillars grow, see if you can tell someone in your family all about it, or make a diary with pictures and sentences to explain how they grow! The end!




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