It was a warm and sunny bank holiday on Ramsey. Normally a time when we share this spectacular island with our lovely visitors and supporters. Hopefully this blog goes a small way to compensating for that in these present times. The birds don't stop for bank holiday though and they were making the most of the lovely weather before a cold Arctic snap arrives on Sunday. Whitethroats, one of the last migrants back from Africa were seemingly singing from every bush on the south path and an increase in house martin numbers saw the nest boxes on the back of the house being inspected. The ones on the front are well established with nest lining being taken in yesterday.
Bird of the day was a house sparrow, the second of the spring. Relatively common on the nearby mainland (although it has declined significantly nationally) a splendid male was 'cheeping' away in the garden all morning.
Male house sparrow this morning - common for some but a real island scarcity
At least one merlin is still around and was seen to take a swallow this morning - too quick to capture on camera, it was a spectacular sight. No sign of yesterday's ring ouzel which was the 4th of the spring, a good year. The red kite that seems to have been around since March was joined by 4 others yesterday. Fantastic birds, one of my childhood favourites.
While most progress reports are made via the trail camera footage, today saw the weekly full check on our Manx shearwater nest boxes and I'm delighted to say we have our first egg! The nest boxes are based on a design from New Zealand and allow us to access birds safely and easily without the difficulty of digging access hatches over natural burrows. This in turn allows us to monitor productivity (the number of young reared per pair, and to weigh the chick as it grows - both vital indicators of wider ocean health). Some birds will also be fitted with miniature tracking devices so we can track their migration routes and over wintering areas in Argentina - important factors when you consider these birds spend more than half the year away from the sanctuary of their nature reserve island breeding grounds
The single white egg of the Manx shearwater will be incubated for an average of 51 days, an astonishing length of time but this slow development of the embryo allows for periods of 'cooling' when the egg might be left for several days if the incubating adult gets tired (or rather hungry) waiting for it's mate to swap over and is forced to head out to sea before the partner bird returns.
After the female lays she usually heads out to sea soon afterwards and leaves the male to carry out the first incubation stint. They swap over every 3-4 days on average but I've known some do 7-9 day incubation stints - no doubt very keen to get back to sea for a feed when the partner finally relieves them! (it is periods like this that can see the egg 'abandoned' for a day or two)
I know this bird well. It first bred in 2017, with the same partner but in a different box (box 38) and raised a very good (i.e. heavy) chick to fledging. They then failed in box 38 in 2018 (I found the egg abandoned outside the burrow, probably as a result of a skirmish with a non breeder trying to take over the box and the egg getting dragged out of the tunnel in the melee). Like most pairs, after failing, they moved nest site and in 2019 were initially found in box 10 but didn't settled there, eventually laying in box 16 where they successfully raised a chick. This is the same box they are in this year - they certainly keep us on our toes and put our spreadsheet skills to the test!
I'll keep you posted on progress with this pair and all the others. Last year we had 11 pairs lay eggs with 9 hatching and all 9 successfully fledging. It's hard to say for sure how many eggs we might have this year but it looks like 12-14 boxes are in use to some extent but some of those will be newly acquainted pairs that won't breed till 2021. More news as it breaks!
(all nest visits, ringing and deployment of tracking devices is carried out under ringing licence from the BTO)
Very exciting observations on the Manx shearwaters front !! Loving the blog.