Friday, 28 October 2016

October Update

October is the busiest month on BI in terms of establishing the bird work for the season. Northern giant petrels, grey-headed albatross, black-browed albatross and gentoo penguins are all at their peak of establishing nests and laying eggs whilst the macaroni penguins return, wandering albatross work continues and initial monitoring is done of blue-eyed shag, southern giant petrels, brown skuas and light-mantled sooty albatross. Then of course we mustn’t forget the returning fur seals, leopard seal sightings and elephant seal pups!
The sooties carry out synchronous flying displays as a courtship ritual, it is amazing to see them fly so close and identically to each other! Unfortunately my bird flight camera skills aren't up to much at the moment, so here is one slightly blurry sooty instead!
So in order to keep up with all this work we have been incredibly busy over the past couple of months, the daily visits to the bird colonies starting in early September, but there has been so many amazing things to see!
 

Giant Petrels


As my main study species I have spent most of my time with the geeps of late. The northern started breeding in mid-September and reach a peak of laying their eggs in the first few days of October.
To monitor their nests I have to put a stake with identifying numbered tag next to each nest, GPS its location and get the details of each bird on the nest, done via its ring number. Once both birds are confirmed for each nest, females are noticeably smaller than males, and then it is a case of checking it regularly, from a distance, to see how they progress through the season.
Laying the egg is rarely seen
The rounds of the geep study area take a minimum of 2.5 hours but when there are plenty of new eggs and partners to check then it can take up to 6 hours, and all this before other species are taken it to account! This makes field days quite relentless when they are done every day for a three month period (September, October and November) no matter what the weather. There has been plenty of wet (driving sideways rain and snow) and windy (gusts of 35-40kts) days on our little island making some field excursions particularly trying. But when the wildlife is this amazing we can’t help but love this job.
Marking the geep nests
In late October the daily work for the northern geeps stops as they finish laying their eggs and they start getting checked just once a week for survival as we eagerly await the chicks to hatch in a couple of months. But just as the northern stop, the southern start and daily checks of them begins in mid-October.
The southerns are now nesting as well

Penguins

Gentoos come ashore most in the evening
Although the geeps get the title of my main study species the penguins come in a very close second! Throughout October the gentoo penguins have a large focus as they build their nests and lay their eggs.
The first gentoo egg of the season!
There are 7 colonies of gentoo penguins on BI but my work initially focuses in just 2 of them, Johnson Cove and Square Pond. In these two colonies I have study plots of a number of nests that are checked every 2-3 days for the presence of eggs.
Large rocks make finding study nests easier!
Gentoos are very variable in their breeding season timing, unlike most birds that start at similar times each year the gentoos could lay their eggs any time between late September and Late November! Therefore, to know when we will have to check on the chicks later in the season we have to establish when 75% of nests have eggs at this time of year. From this date all following works can be calculated for optimal timing.
The gentoos are very proud of their eggs!
The gentoos started laying their eggs on the 1st October this year, a couple of weeks earlier than the average, and reached their 75% date in the 2 main study colonies by mid-October. This meant that all 7 colonies were due to be counted in late October for number of active nests.
An Isabelline gentoo - a rare morph
Standing on the periphery of each colony in turn we spent a lot of time over the course of one weekend counting 3,800 nests! Lucy joined me for day one (Johnson Cove and Square Pond) and James for day two (the other 5 colonies) with the number of nests very even between the two days. It is great fun spending time with the gentoos, particularly as they now continue their breeding season until January when the next piece of work, counting their chicks, without regular monitoring. Let’s just hope they actually get some chicks away this year!
We had to wrap up warm during the count, standing still for a while made the cold worse (Photo courtesy of Lucy)
Whilst the gentoo work is on certain occasions through the season the macaroni work is a bit more regular, but first we had to wait for their return! The first macs were seen on the 17th October and it is very strange seeing a large colony like Big Mac with just a handful of penguins in it! But after just a week the number of penguins had gone from a few to well over a thousand! They won’t stop there either, Big Mac will reach 40,000 before long and their noise will be heard constantly through the season.
Spot the first macs at Big Mac! Harder than a Where's Wally!
The macs are amazing little characters and our intial work is all about seeing how well they have done over winter. At Little Mac a weighbridge is set up to get weights of the birds as they arrive but at Big Mac the weights are collected manually. This means spending an afternoon at the entrance to the colony and weighing 50 male pingus (50 females are weighed in early November as the females return a bit later).
We were really excited to be working with macs again :)
Now that the macs are back I will be visiting the Little Mac colony on a weekly basis to check on the weighbridge. They were certainly a highlight of last summer and I can’t wait to spend a lot of time over the next 5 months with these characters again!
Macaroni penguins - can't help but smile every time I see them!

Mollymawks


Of course it isn’t just my study species that are kicking it to high gear at this time of year. Lucys albatrosses are also starting their season and laying their eggs. In particular the grey-heads and black-brows are filling up their colonies and laying their eggs. Lucy monitors them in much the same way I do the geeps, tag nests, check partners and use ring numbers to identify the birds.
Black-brows arrive a bit later than grey-heads, but both are laying eggs in October
At this time of year there is so much going on that we often help each other out so I have been fortunate enough to check the mollies on occasion myself. Finding the first grey-head egg of the season was a great moment and it certainly reminds us how much we have missed these striking birds over the winter!
Grey-head getting mucky building its nest

Wanderers


Unlike the geeps, mollies and pingus the wanals are actually still in the previous season! The chicks are getting very big now and fledging will start in mid/late November. Just in time for the next cohort to begin nesting in December.
They may be growing up, but they still love seeing their parents come in.... because that means food!
Work with the wanals is therefore a bit quieter in October as the main study area is checked on a weekly basis, but it is always great to have an excuse to see these awe-inspiring birds again before they take their first flights.
A wanal chick looks after my geep stake posts for me!
My, what big wings you've got!

Other birds


Whilst initial observations have been made of skua, sooties and shags the majority of work for these species’ is carried out in November to January, so there will be plenty of updates on these species as we progress through the season. Burrowing petrels, particularly white-chins,also take our attention at times through the season and I can’t wait to work with these little guys again!

Shags nesting and having their quiffs blown in the wind

Seals


So there is a lot of bird activity in October, but we are still treated to a change in the seal season as well. James is still out on a daily check for leopard seals at this time of year and whilst numbers have certainly decreased since the ice has gone and temperatures have ‘warmed’ up (it’s a balmy 0-2°C nowadays!) there are still enough sightings to keep us happy.
Haydn the lep is still a fairly regular visitor
Whilst the leps may be declining in sightings our attention has been taken by the elephant seals. BI is not a major location for ellies; compared to colonies on South Georgia itself which number in the 100’s our few dozen ellies seems like a small amount. Whilst there may not be many we have seen 11 different pups in various places across the island and seeing the huge males bellow at, chase, and even occasionally fight each other is one amazing wildlife spectacle!
A sub-adult male enjoying a scratch, the big guys aren't this cute when fighting!
A pintail stands guard over a male ellie claiming his female!
The first ellie pup of the season :)
He's ermmmm, cute?!
Leps are the winter seal species and ellies are concentrated at this time of year. But over the past couple of weeks we have started getting signs of what is to come, the return of the furries! Whilst fur seals are present in low numbers on BI through the year the breeding individuals only start to arrive in October when the big males start claiming their territories.
Male ellies chase each other with a lep, immature ellie, female ellie and furries looking on
Throughout November fur seal numbers will greatly increase and James will be kept busy with daily checks in his study colony from the 1st November; it won’t be too long after that for us to wait until the first pups as well! But for now it is all about us getting used to the smell of the big guys outside of base again!
A big male has set up his territory under the living room window!

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