So with the news that the first Black Guillemot egg was laid on Rockabill last week (see Friday's blog post here), we've started to check all of our Black Guillemot nest-holes and nestboxes for eggs. There were no new eggs on Saturday, but we found another four yesterday, belonging to three different pairs - two eggs in a nestbox, one in a hole in a stone wall (see pic below) and another in a hole similar to the one where we found the first egg on Friday!
|Several of the larger holes in this stone wall are used as nesting sites by Black Guillemots.|
|Black Guillemots (Picture taken under NPWS license)|
The picture below shows the size of a Black Guillemot egg. This egg was found on one of our first days on the island and was one of last year's that didn't hatch. The colour is a bit washed-out from all the weather over the last 12 months - their eggs are similarly spotted but are a light shade of blue.
|An old Black Guillemot egg, around 2.5 inches long. The blue colour has faded but you can still see the spots and markings that give the egg camouflage.|
|The first egg found on Rockabill this year - a Black Guillemot egg. (Picture taken under NPWS license)|
Black Guillemot eggs take 28-32 eggs to hatch, so we should see their chicks in mid-June. Until then we'll have plenty more nests to monitor and eggs to record!
- Brian and Donnacha