When the nestcam feed from Nest 1 started up on Friday morning, it didn’t take long for a female to appear on the nest. But hang on, it wasn’t either of the two who have been trying to win YA! And on close inspection of her head and chest markings she looked very like YA’s 2012 mate. She was on and off the nest for about half an hour and then YA made his appearance, mantled for a few moments, and mated with her. Although YA was mantling, there did not seem to be tension between them. Mantling is defensive or submissive, and is often observed when a pair meet up again after months apart.
Similar behaviour was observed throughout the morning. YA’s reaction to this osprey is so different to how he was with the dark headed female (he was not comfortable with her for several days) and the recent intruder (who he did not mate with at all, as far as the nestcam showed). He even brought some moss to the nest, quite an achievement for him! There were significantly more mating attempts than seen with the dark headed female. At 12.30 he flew over the nest with a fish. The female was probably nearby and the fish must have been consumed in the trees as the nest stayed empty for some time. Later in the afternoon there was less action but YA did bring more moss in, fiddled with twigs and scooped the egg cup.
So the strong likelihood is that YA’s mate has just returned from migration. There have been a lot less sightings in the South this week, but still some in the Midlands and North, and this osprey could have been one of them. What will happen to the other females? They may stay around the Kielder area looking for a different mate. The dark headed one has mated a number of times, but could reabsorb any eggs that have been fertilised. She would not be able to incubate eggs and fish for her food, so if she does lay without a mate the eggs will be abandoned. It woud be great if she finds a male, and uses another of the nest platforms around Kielder!
Hopefully it isn’t premature to say that what has happened on both Kielder nests over the past couple of weeks is further evidence of the strength of the pair bond between osprey couples. Both 37 and YA ‘consorted’ with new females, but they responded immediately to their mates’ return by choosing their old partners.