The Ringing of the Manton Bay Chicks

Peter Cairns/2020VISION

Yesterday marked a very exciting day for us, as it was the time when a small team of us, led by a fully licenced ringer, would be heading out to ring the two nearly six-week old Osprey chicks from the Manton Bay nest.

All the Rutland Ospreys are fitted with leg rings when they are approximately six-weeks old, which is an optimum age as the chicks will have grown enough for the rings to fit. Ringing the birds allows us to gain a fascinating insight into individuals’ movements if they are observed elsewhere in the UK and abroad. Yesterday marked a very exciting day for us, as it was the time when a small team of us, led by a fully licenced ringer, would be heading out to ring the two nearly six-week old Osprey chicks from the Manton Bay nest.

Dawn is such a peaceful time of the day, and as we arrived on site we were immediately greeted by a Cuckoo calling away in the nearby hedgerow, and for me, like the Osprey, Cuckoos are one of the signs spring in the UK has really set in. But we soon disturbed the peaceful tranquillity of the morning, when Maya spotted us and began circling and displaying in the skies above us; the air ruptured with her alarm calls, as she attempted to warn us off, evidently aware of our presence and perhaps intent. After all, this would be the 10th time we have disturbed her to ring the chicks. 33(11) soon joined her and any remnants of calmness soon escaped. Well, for them at least. It is of course a special moment for us to just be immersed in the atmosphere and the moment.

(Make sure your sound is turned on for the video below)

After pulling up to the nest in the boat and fastening the ladder securely into the water it was time for the chicks to be safely lowered down in to the boat, in preparation for ringing and taking biometric measurements – which indicate the sex of the individual. All the while we were there, Maya and 33(11) were continuously alarm calling, inadvertently helping the whole process as, in reaction to the parents’ alarm, warning of them of potential danger, the chicks will hunker down in the nest relatively motionless, which allows for easy handling.

The chicks were then gently lowered down into the boat and were ready to be fitted with their BTO issued metal ring on their left leg and in addition the blue Darvic ring on the right leg, allowing us to more easily identify the bird using a telescope or camera. What really grabbed my interest was the design of the blue ring. I had always assumed that the ring would be fitted the same as the standard BTO metal ring with a pair of ringing pliers. However, the blue ring is coiled around and as the ringer carefully wraps it round the leg of the chick, it needs to be secured using a particular type of glue, causing no harm to the individual. I guess you learn something new every day!

Unlike other raptor species like Kestrels, distinguishing between male and female Ospreys is not overly straightforward and it takes time and experience to recognise characteristics particular to males or females by eye. Some features that vary between the sexes usually are female Ospreys have a more heavily brown colourings on their chests in comparison to the males and are much heftier individuals, but judging if a bird is male or female based on size can be tricky unless you have a male and a female sat next to each other.  

Even though the chicks are only six-weeks old, it is still possible to determine the genders of them, by taking measurements such as weight, wing length, the length and depth of the bill as well as the length of the chick’s lower leg, or tarsus for want of a more scientific term.

The first chick that was ringed was actually the younger of the two, due to the fact the stage of development of its feathers was a slightly behind the oldest and we were really eager to learn that this chick was a female and was given the ring number 095! And then the whole process was repeated with the second chick, which turned out to be a male. He was fitted with the ring number 096 and was seemingly smaller in the hand than his sibling. It was quite remarkable how obvious when looking up close how much chunkier both the female’s tarsus and bill were in comparison to the male’s.

Ringing is the only time these Ospreys will be handled and it is done as quickly as is safely possible and is always done by someone who has all the necessary certification and experience. As soon as the ringing was finished - and of course after we made sure the camera was spotless - the chicks were returned to the nest and we left the Manton Bay family to resume their normal way of life.

Later on, we were reassured to learn that as soon as we had hit dry land, Maya landed on one of the perches next to the nest, as if nothing had happened. And it was only after a couple of hours later, 33(11) delivered a well-deserved breakfast for the chicks. It will now only be another two or three weeks before the next chapter of the chicks’ life will begin – flying.

It was a real privilege to have this fantastic opportunity to witness this moment first hand and this whole experience has to be one of the highlights of my time working on the Rutland Osprey Project so far.

** The ringing of the two Manton Bay chicks was completed by a fully licenced ringer, who has extensive experience in handling these amazing birds. **