They are back! The Salisbury cathedral Peregrine Falcon nest cam went live again on 11 March 2021. Yes, like in March 2020 we are still in lockdown, but do spare some time now and again (or maybe again and again) to watch the fascinating goings on at the nest site; it is surely a bright note in these otherwise rather trying times. Last year there were no fewer than 600,000 hits on the website between March and August, peaking at around 15,500 viewings on 30 April, with up to 1000 people viewing the site simultaneously on occasions. What will 2021 bring?
Members of the public regularly walking past the cathedral will have recently noticed increased activity from the birds. Whilst the pair occupy the site all year round, it is only with the onset of the breeding season that they become more conspicuous and their vocalisation increases as their courtship begins in earnest. As both birds are unringed, even given the close views available from the nest cam, it is not really possible, due to the general lack of variation in plumage between adult birds of the same sex, to say whether one or both birds are the same as those which bred successfully in 2020. Peregrines are generally relatively long lived compared with many smaller birds so there is every chance that at least one, or hopefully both, are those from 2020. Regular watchers from 2020 will however have learnt to distinguish between the male and female birds, especially when in the nest box. The female looks a much more bulky bird, whilst the male is noticeably smaller and, dare I say it, rather more dapper, to my eye at least.
Limited camera footage in early March has revealed that courtship behaviour is well underway. The head bowing display between birds , also known as the Head-low Display, has been noted, and is likely to continue for a while whilst the birds re-establish their pair bond. Early season activity is often accompanied by a rather staccato two note call between the birds. This call, heard on recent camera footage, is known as the ‘creaking’ call, as it was, in early times, likened to the noise of a rusty hinge. It is far carrying and can be heard both on camera and by visitors walking through The Close, quite different to the more familiar ‘Cacking’ call.
Viewers to the nest cam will have noticed that there is already a shallow depression, known as a ‘scrape’ made in the gravel substrate of the nest box. Camera footage has revealed that both birds have been involved in the making of the ‘scrape’. One might imagine that it could be easily created by the bird standing in the nest box and simply scraping out a depression with its feet and then sitting down in the depression and shuffling around to create the desired shape. This is not the case however. In fact the bird lays down on the substrate and in perhaps somewhat incongruous fashion, uses its feet to ‘shovel’ gravel backwards out from underneath itself to create the required depression. Whilst sitting in the scrape, the female in particular, has also been observed pecking at the gravel around herself, often continually for several minutes at a time. This has been observed and commented on by viewers in the past. This process does not seem to be related to moving gravel around to make the ‘scrape’ anymore functional so to speak. It is also thought that, as with other raptors, peregrines might ingest small particles of grit to aid digestion; analysis of discarded pellets might shed more light on this matter. Maybe, especially during the long periods of incubation of the eggs, the birds simply just pick at the gravel for something to relieve the boredom; we will probably never really know for sure.
In 2020, the four eggs were laid between 22 and 27th of March; it will be interesting, and of course exciting, to see when the first egg is laid in 2021!
Granville Pictor 13 March 2021.