Standing at up to a metre tall and with a wingspan of between 155 and 195 centimetres, the grey heron is almost unmistakable. Adults have an orangey yellow, dagger shaped beak, a dark eye stripe which contrasts with their almost white head and neck, grey wings with dark outer edges and a small crest of feathers protruding from the back of their heads. They also have long spindly legs and hold these and their heads and necks close into their bodies during flight. For the most part, males and females look the same although the crest of feathers, which are known as Aigrets are slightly longer in breeding condition males.
Grey herons are mostly a waterside bird, found at all inland waterways, along the coast and much to the annoyance of koi and goldfish keepers, theyll frequently attempt to visit garden ponds. With this wetland preference, a lot of their diet is made up of fish and amphibians but they will also hunt away from the water and take small mammals, birds and insects. They catch their larger prey by surprise, stalking it, impaling it and then swallowing it whole.
When it comes to nesting, grey herons will often choose to nest communally in what is known as a heronry. This will usually be in clusters of large trees on islands or close to water and they will sometimes share their nesting areas with other fish eating birds such as great cormorants, spoonbills and egrets. From the age of two years onwards, each adult heron will attempt to find a mate from early spring onwards and once they are successful will begin the construction of a large twig platform nest. Once the nest is complete, each pair will produce between 3 and 5 greeney blue eggs at 2 day intervals. These measure 6cm in length and are incubated by both parents for 27 days from when the first or second is laid. This means that the chick hatch at intervals too and their can be a noticeable size difference between them. Both parents bring food back to the chicks in the nest and they grow rapidly, fledging at 50-55 days old. At this point the young are duller and scruffier looking versions of their parents and are still cared for away from the nest for a further 2 to 4 weeks until they are able to fend for themselves. Each pair will only nest once per year and after nesting they remain mostly solitary, only searching out a new mate the following spring.
There are currently an estimated 13,000 grey heron nests in the UK and 63,000 birds overwintering here. They are also found across most of Europe, Russia, northern Asia parts of Australasia and south Africa. They have a close and similar looking relative in the Americas called a great blue heron. Grey herons in the UK dont migrate and at some point outside of the breeding season they can be seen stood along a waterway or in a field all facing the same direction, and no one really know why they do this although it is thought it might be just for social interaction. They have an average lifespan of around five years but the oldest wild bird on record made it to 23 years of age.
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