Various messages express the disappointment with the down-time of the webcam this morning, following a similar outage on Thursday as the University undertook maintenance on servers. Today’s problem seemed likely to keep us on tenterhooks for the weekend, but a fantastic effort by Ian Knowles and the CICS team has resolved the issues, conscious that this weekend is a crucial period. I’m far from an expert on such matters, but Andy D tells me that he’s managed to overcome problems with viewing the webcam on android devices by installing (free) Photon browser that supports Flash. No doubt there will be other ways of doing this, and other browsers are available!
Thirty days after the clutch was completed we’re in the midst of the range of dates when the eggs are expected to hatch, with Monday at the outer end of the spectrum. No sign of hatching today as both adults take turns to incubate, the male still reluctant to leave the eggs at times when the female arrives, and again doing around half the time on the eggs, ring visible as he arrives below.
Since commenting on the male standing on one of the eggs, it’s been noticeable that the female is careful to avoid doing so, holding her foot closed and dangling – a bit as the male is doing in the picture above – as she settles. Her greater weight (950-1300 grams for an adult female compared to 600-800 grams for adult male) would no doubt increase the risk of damage to the eggs should she stand on one, but it’s hard to know if there’s a gender difference in behaviour here. One change I’ve seen today was the female being less assiduous in her incubation duties, pecking at stones in the corner of the box and leaving the eggs exposed.
Could this indicate that she has heard movement or cheeping from the eggs and knows hatching is imminent? The periods when the eggs are left uncovered are a little longer than they have been in recent days and weeks, another possible indication that behaviour is changing slightly. Or perhaps I’m reading too much into things!
With today likely to be one of the last chances to see the eggs, a comparison above shows how they have faded over the past month, which is typical as they are rubbed by the adults’ feathers. On the left above is the clutch on 27 March, the day the fourth egg was laid, while on the right is a picture from today. Apart from seeing that the darker and lighter pairs of eggs have both faded roughly equal amounts, it’s also interesting to note that they’ve changed position in relation to each other, no surprise given the amount of turning and shuffling that’s taken place over the last few weeks. I’ve read that not only do Peregrines tend to lay the same number of eggs from one year to the next, but that the eggs themselves can be quite distinctive between females. Not sure if that’s the case with this female: this image of the recently completed clutch from last spring does look to have two eggs a little darker than the others.
It’s just occurred to me looking at this that the eggs have been laid and incubated in a very similar position within the platform to last year, and it’s reminded me of what a terrific platform we have this year. Enough of the eggs, but I thought it was worth reflecting a little on them as we hope to move on to the next stage, perhaps tomorrow!
Finally, Peregrine fact of the day: the hatching of all eggs at roughly the same time (synchronous hatching) is taken as an indication that food supply is not a limiting factor for Peregrines and reduces sibling rivalry.