The heronry on the lower (sailing) pool at Gailey is well know in the West Midlands, and is one of the longest studied colonies in the UK. Up until a few years ago the late, great Bert Coleman organised the ringing of the Grey Heron chicks, and for the last couple of years, we have taken on the role. Lock-down obviously caused a problem, but last year we did manage to start a new programme of colour ringing the chicks in order to try to find out more about their dispersal, and potential return to the site.
One of the difficulties about ringing a colony of Grey Herons is that the nest asynchronously. Many colonial nesting species, prefer to have their chicks all develop at the same time and have evolved behavioural strategies to achieve this. For some reason, this species is happy for chick development to vary immensely. The difficulty from our point of view is knowing when is the best time to have the maximum number of chicks ready to ring at any given time. In truth, it's a mixture of regular careful observation of the colony ( from the nearest dry land), calculations--and luck!! Just to illustrate this, several of the nests were still incubating eggs, some had very well developed chicks which were ready to fledge, such as this one....
....and from observations as early as February, some chicks had already fledged and left the nest.
Our good friend Tim, from the sailing club kindly offered to take our group out to the island colony on Sunday morning and we stayed for the traditional time of just over 1 hour in order to minimise the disturbance. The more experienced members slid into action immediately and sent chicks to the ringing
base where Kev and Scott took charge--first putting on a classic metal ring on one leg, and a uniquely numbered/lettered 'Darvic' plastic ring on the other, as you can see here...
Sessions like this afford a great opportunity for trainees and anyone not familiar with this species to gain invaluable experience. Here is trainee Shaun getting expert guidance from Scott, to ring his first heron....
And here's Liz after one of her first heron interactions--note the snazzy safety glasses which are really helpful with such big, sharp beaks around the place....
After a pretty slick operation all the chicks were safely returned to their own nests, as Paul is doing here....
In the end we ringed 18 Grey Heron chicks, and estimated that there were 25 active nests. However, because of the variation in development we estimate that a good number of chicks will be ready for ringing in about 10 days time, so with luck we will be crossing again to finish the job.
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