Swan on nest (1 Viewer)

[Joy UK]

Hi, during lockdown we have been enjoying daily walks around our local large pond. It is a pretty quiet area of open water surrounded by dense reed beds, situated in Warwickshire. We first noticed the female swan sitting on the nest at the start of lockdown , so around about mid March. She is still sitting on the nest today, 11 weeks later. We have seen her off the nest in the reeds near it once or twice in this time. We are only able to see it across the water and there is no access near the nest from the paths so I don't think she has been disturbed by humans. Does anyone have any idea what might be going on? This pair normally raise at least 5 cygnets every years.