Heron

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A grey heron 1024px-Graureiher_Grey_Heron.jpg
The scientific name for the grey heron is Ardea cinerea and they are in the bird family herons, storks and ibises. Their population is doing well under The Wildlife and Countryside Act and they have a green UK conservation status meaning they are under least concern. They are very easily recognisable with their tall long legs, long beak and monotone feathering. They feed on fish but do also eat small birds and small mammals such as amphibians. They also eat some rodents after fields are harvested in agricultural areas. They weigh up to 2 kg and have a wingspan of just under 2 m. In the UK there are 13,000 breeding nests and during winter in the UK there are 63,000 individual birds. Grey herons are the largest bird you could see in your garden but despite their size they are very light weight.

A pair of heron building a nest. Ardea_cinerea_building_nest.jpg
Herons breed in colones that are called heronries. They are usually in high trees of close to waterbodies such as wetland or lakes. Every year herons use the same nest unless they have been destroyed or blown down. The nests start as quite a small bundle of sticks and then as more is added it becomes quite a bulky nest as more material is added every year. The males collect the material and the females build the nest then during February to June the breeding season begins. When makes get to a chosen nest site they begin to court which involves him calling. When females arrive at the nest site, both the males and the females involve themselves in a stretching ceremony in which each bird extends their necks upwards before swinging it around all while flexing its legs. When the pair is happy together they caress each other by picking at each others plumage. The next step is for the male to offer the female a stick that she will them add to her nest causing the male to become more excited and copulation occurs. In a clutch there is normal around 3-5 eggs that are laid at two day intervals whilst incubation is also taking place. Incubation takes place for about 25 days. After the incubation period with the mother and the father collect food for the young. 7-8 weeks later the young fledge. The first year of their life is tricky and only one third of juvenile heron make it into their second year due to predation.

Threats to herons include predators and parasites. Due to their large size and strong beaks, the grey herons have minimal numbers of predators in their adult form. However, the young and eggs are very vulnerable. Parents very rarely leave their nests as they know the dangers that leaving can have on their young. Some grey herons have been found to host 29 species of parasitic worms which affect their health.

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