First day of spring?

On Sunday, it seemed spring had finally arrived, the sun was shining and the temperature (in the morning at least) reached 16 degrees. As a result there was more activity along the river:
Such as a peacock butterfly - possibly just risen from hibernation and basking in the sun, maybe a male defining a territory.
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The lesser celandine is now in flower, providing food for a tortoiseshell butterfly, also risen from hibernation.
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Another insect rising from hibernation is this queen bumblebee.  Bumblebees often make their nests in defunct small mammal burrows, so perhaps she is checking out the suitability of the water vole burrows along the river banks.

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Not all animals have chosen to spend the winter in hibernation, some choose to spend in a different country, including the warblers and have now started to return - such as this chiffchaff -  to make the most of the abundance of insects which spring and summer along the river should provide.
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