Bricks

Anyone who has followed my blog in previous seasons will be familiar with my numbered nest marker bricks. 

My first job of the season is to lay these out through my penguin colonies to individually indentify 100 nests of each species.  I will then visit each nest every few days throughout the entire breeding season to get laying, hatching and fledging dates.  These nests are important as they act as a representation of the island as a whole, so I know when to do the large scale counts.  For example, when the birds in my study nests have finished laying it is time to do the island wide egg count.  Because the arrival dates for the birds can vary quite considerably, the date varies from year to year and the results would not be comparable if the egg count was always done on a set date in the calendar year.  The whole point of me being here is that it is a long term monitoring site, and my role is to collect this years data for the longterm dataset, which for Signy now spans 40 years.        

When i arrive at Signy, the breeding season is already in full swing.  The Adelie penguins have been back at Signy since early October, and by the time I arrive they are busy incubating eggs.

Their neat little nests are built from pebbles.  Although both parents incubate the eggs, only one bird is needed at a time.  Their behaviour gives you a clue as to what they are doing- the birds in the picture below that are standing up will be failed breeders- either ones who somehow didn't quite get something right, or ones where the predatory skuas have pinched their eggs.  They will not breed again this year.  The laying down birds will be incubating eggs.

 

This one has two eggs and is standing up briefly to adjust them and check they are still there.

The chinstrap penguins always breed about a month later than the Adelies.  When we arrived the male birds had already arrived and were fiercely defending their chosen nest sites from fellow penguins. 

Nest building requires dedication.  Leaving the nest site for too long leaves the risk of someone else coming along and taking it over, resulting in some fairly vicious fighting.  Alternatively they may return to find a neighbour has pinched all of the carefully chosen stones for their own nest.  It is not uncommon to watch one bird wandering backwards and forwards stealing a neighbours stones, while someone else is doing the same with their own nest. 

Now, a couple of weeks later, the females have also arrived and the chinstraps are in the middle of the egg laying period.  The Adelie chicks should start hatching any day now, but I haven't seen any chicks yet.