Nesting in the Tree Tops

Spring is here! The daffodils are in full bloom, the blossoms on the cherry trees add a splash of pale pink and white to our streets and the birds have started singing, a sure sign the nesting season is starting. For some birds however nesting has been in full swing for at least a month, one such species is the grey heron.

An unmistakable bird, with long legs and a long beak, the grey heron is typically seen stalking the edges of pools and rivers in search of their fishy food. It is surprising to discover then that they nest at the tops of trees! On a large nest of twigs and sticks, reminiscent of a pigeon nest, grey heron’s typically start nesting in February, laying between 2 and 7 eggs which hatch after 23 to 28 days.

Nest recording for grey herons high in the tree tops

North Notts Ringing Group has been ringing nestling grey heron since the early nineties. Although numbers of grey heron across the UK are increasing slowly and the species is by no means rare, numbers at this colony have seen quite a dramatic decline over the last couple of seasons. The reasons for this remain unclear, hence the importance of continuing to monitor nests and ring chicks. This year, in response to requests from the British Trust for Ornithology, the group is colour ringing the chicks, adding a blue ring with white letters along with the metal ring. Colour ringing should improve the reporting of sightings for this species, which is generally only recovered once a bird dies… but what happens in between? Where do the birds move during their lives? Do they stay in one place? Return to their natal colony to breed? Colour ringing could help provide the answers to these kinds of questions.

Grey heron chick

So this Saturday, Lee and I headed up to Besthorpe Nature Reserve, near Newark to help ring the first load of chicks for the year. With the mist clearing, we headed over onto a small island in the middle of a lake. As Jez climbed to the tree tops, we waited below, recording the contents of each active nest and waiting for any chicks that could be ringed. Quite a few of the nests had small chicks or eggs, but three nests had chicks large enough to ring. Delivered down to us in a bucket, we ringed the chicks, placed a colour ring above the knee of the right leg and weighed them. After a quick photo call, the birds were returned to the nest via the bucket…

Me and my first grey heron chick

In all nine chicks were ringed from three nests. The team will return to ring the remaining chicks over the next couple of months. Its then just a question of keeping eyes peeled for colour ringed birds, over the next few months as they leave the nests and over the next few years to see if they return to breed.

If you ever see a colour ringed bird of any species, please report the sighting to the BTO. Record the combination of colour rings, or the colour and letters on the ring. Sightings can be reported via www.ring.ac. 

Likewise if you ever find a bird with just a metal ring on then please report that too!