The adventure is over.....January 4th

The black robin

What a busy weekend. All the packing took a huge amount of time and due to all kinds of circumstances we didn’t know until 8.30 on Sunday morning that we were going to leave on Sunday at lunchtime. Of course we were organized and by 12.30 we had everything, and I do mean everything, on the rocks, all ready for Glen and the Acheron to pick us up. When we spotted the boat coming around the corner of Pitt Island we knew that that really was it. We were headed for home.

Views from the top of Rangatira Island on a clear day:

We all sat on the deck, surrounded by buckets and fish bins watching the island as it got smaller and smaller on the horizon. There was the Summit where we had spent Christmas afternoon, and the Trig where we had spent Christmas night. There were the cliffs where Melanie and Brigitta had gone to on Melanie’s birthday when the winds were about 40 knots. There was Whalers Bay, my favourite place, where we had swum in the rock pools. There were the skuas flying around Front Landing. And in the bush somewhere were all the robins, the tomtits and all the other forest birds, continuing their lives as though we had never been there. We were all very quiet.

At 2pm, over the noise of the engines and radio, we heard the marine radio; “This is Chathams fishermans radio, Chathams fishermans radio.” The forecast for the next three days is wind, rain and 4 metre swells. We had left just in time........

Photos from Rangatira:

GPS and logistics - January 1st

Happy New Year! We had a very quiet night last night, or at least we were very quiet and I think all of us were in bed well before midnight. Brigitta was due to put out the very last camera this morning, and I was going to go with her at 4.30 to sit on the rocks at Whalers bay and be one of the first people to see the sun rise on a new decade. It was wet and rainy though, so although the sun must have risen it is never so impressive seeing it through the clouds, so I went back to bed and to sleep.

Sunrise on Rangatira Island:

Sunset on Rangatira Island:

For the last week Brigitta has been in charge of GPS-ing the nests. GPS, or global positioning system, is a US based navigation satellite system. We use a hand-held device that connects to a few of those satellites, usually 6 or 7 of them, and then calculates where we are in the world to a distance of about 10 metres. This will give Melanie a map of the Island with dots on it showing exactly where all the nests are. Brigitta also records the height of the nest from the ground, how high the tree canopy is above the nest and how big the nest is. These data will give Melanie yet another piece to help her solve the puzzle of the Island birds lives.

After Brigitta has taken her measurements, and this is when we know that we are really leaving in two days, we take the pink nest marker tags down. The Island definitely looks less festive without its pink tags.

Cleaning the kitchen......

The other big job of the next few days is of course to pack. Imagine the huge piles of gear, let alone food and clothes, that you need to bring for a three month research trip on a remote island. The food of course we have eaten, but everything else, including our rubbish, has to be carried home. We have a lot of electronic gear, and as we travel to and from the Island by fishing boat, we need to make sure that it is double bagged against the dreadfully corrosive effects of sea water. Everything else goes into watertight buckets.

Buckets packed waiting to go:

Once we have a bucket packed we take it down to Front Landing and store it there until we actually leave. On Sunday we’ll carry all the buckets across the rocks at Front Landing to the point where the ship will pick us up. We can’t do it any earlier in case there is bad weather and high seas and we don’t want anything to get washed off the rocks. Of course we also have to clean up the hut, eat up lots of leftovers, say goodbye to our favourite birds and places, and close everything up before we leave. I’d better get to it!

Rangatira Island Street - an endless soap opera: December 31st

It’s the last day of the decade, and we’re spending it dodging rain showers and finding out the last bits of bird gossip to complete the endless soap opera that is the life of the Rangatira Island Black Robin population.
On Tuesday we caught and banded two female robins up on Whaler’s Track. Melanie knew that there were three un-banded black robin moms in that area. But we didn’t know which of our newly banded girls belonged with which robin male. Annika was sent to find out. She worked out that we’d banded Findlay James’ mate pale blue, metal, white, fluorescent pink and Tawhitis’ mate dark green, metal, yellow, fluorescent pink.

Aren't they cute!

The un-banded female, which we’d still love to band, turns out to be June, Cash’s mate. Annika found their nest this morning and they have one egg. We’re not going to be here to see it hatch, which is a shame because if she had been a girl we would have called her Roseanne!

All these extra little bits of information makes the black robin database as complete as possible so that there is an accurate picture of who is related to whom.

We are hungry!

I went back to KD 24, Raginis’ and Lorenzos’ nest, this morning to see my favourite chick. He is probably a male as he is huge and fluffy, so I’ve named him Pip short for Pipsqueak! He may have fledged when I go back tomorrow, so I wanted to say goodbye to him and wish him well.

Regarding tomtit news, we were worried that we had disturbed Agatha and Eiko last week by banding them, but were delighted to go back today and see that their chicks Aroha (named after my niece) and Ben and Zoe (named after my oldest friend’s children) are still growing and are also due to fledge soon.

It’s hard to believe that in a few days the forest birds will be getting on with their lives and not only will we not be here to see it, we’ll know nothing about them until the next time a research team arrives to update us.

Eggs - care required when handling! - December 30th

As it is a wet day here on Rangatira, one of my jobs this morning was to sort out the eggs that we have collected and pack them safely away.

Black robin eggs are small and cream coloured with light brown speckles on them. The female will lay up to three eggs at once and each one will weigh about 3 grams. The females do gain weight before they lay the eggs, but with an average female weighing only about 20 grams, the eggs are a huge percentage of her body weight!

What a collection of eggs!



The egg shell has a thin membrane between it and the chick developing inside, which you have probably seen if you’ve ever peeled a hard boiled hen’s egg. The egg shell and membrane are permeable, so they let gasses and water in and out of the egg through tiny pores in the eggshell.

The developing embryo in the egg gets its food from the egg white, which is full of protein and liquid and the egg yolk which is full of nourishing fats. By the end of incubation the egg will have lost about 10-15% of its weight due to loosing water across the shell. After developing in the egg for about 18 days the embryo will start pipping. First it pips internally, which means that it breaks through the membrane between it and the shell. The parents can tell when this is happening and stay closely on the eggs during this time. Once the embryo has made its way though the membrane, it uses its egg tooth, a small tooth like projection on its beak, to break open the shell. This is a huge effort for such a tiny creature and the chicks hatch out quite exhausted. They do still have a bit of the yolk left inside their bodies in an internal yolk sack and this gives them food and energy for a couple of days after hatching.

The black robin chicks are then nestlings for approximately another 21 days before fledging. Sometimes the female will have one nestling and still be sitting on an egg that failed to hatch. When this happens we remove the dud egg from the nest. We very carefully break the egg and write down why it didn’t survive. We also dry the shells so that Melanie can take them back to the lab. She then puts the shells under a scanning electron microscope and looks at the location and numbers of pores that are on the egg shells.

A nicely dried egg

Dissecting eggs that have been incubated for over 20 days, can be really smelly work and we make sure to do it outside not to cause too much of a stink in the hut. One egg that we dissected last week was so rotten that it exploded as soon as Melanie broke it, and the smell was spectacularly bad! Thankfully the one I did today just looked like it had been scrambled inside the shell, and only smelt a little bit. So I carefully washed it out and put the eggshells out to dry, then went inside to a hot cup of tea and some wet weather board games.

Front Landing - the Riviera of Rangatira - December 29th

Welcome to the Rangatira waterfront. This is where we all leapt off the boat that first day, and probably is where we’ll leave the Island, depending on the weather and wind direction of course. There are other landing areas but Front Landing is the closest to the hut. Front Landing has a rock platform with the sea on either side of it. The rocks are home to all sorts of wildlife including the shore plovers who squeak constantly while you’re on the rocks. There are also the skuas, which for some reason don’t try to eat the plovers. If I had a neighbour who squeaked that loudly all day I know I’d get grumpy. But it seems that skuas and plovers happily coexist.

A skua:

There is a lot of seaweed and tiny snails on the rock platform. The snails make half of your steps crunchy and the seaweed (a green weed called Ulva) makes the other steps slippery. The platform is far from even and you have to watch yourself as there are some deep chasms and pools here that you could fall into.

Slippery seaweed:

Seals also like basking on Front Landing, away from the busier seal colonies on the other side of the island. You should always keep 10 metres from a seal and never get between it and the sea so that it can escape if it feels threatened. But what I wonder, should you do when there is sea on both sides of a seal? I just made sure to give her a very wide berth.

A seal on the move....

When you look up towards the Island you see the beginning of the forest with the Rangatira Island sign and the chair. We’ve all had moments sitting on the seat watching the sea and reflecting on what has happened during the day. It’s a great view too, over the rock platform and out to Pitt Island.

What a view!

There is so much I’ll miss when I leave here, but sitting here, watching the sea and the wildlife will be near the top of that list.

An unsung forest bird - 28th December

We’re mist-netting as much as we can at the moment to make the most of the still weather. Gales are forecast for the next couple of days and apart from checking nests there is very little that we can get done in the cold and rain. We’ve caught a number of un-banded robins in the nets and some tomtit fledglings too, so it’s been successful work.

We also caught some Chatham Islands Warblers. They are modest little brown birds, with pointy beaks whose song sounds like a cheerful jig. Warblers don’t come when we clap our hands or call them and we can’t bribe them with worms to show us their nests.

Chatham Island warblers are common in forested areas all over the Chathams but only live in native forests and can’t survive in habitats that have been modified. Thankfully there is still a lot of habitat like this left in the Chatham Islands, so they are not endangered.

Chatham Island Warbler chick:

They raise one clutch of eggs per year and sometimes are brood-parasitized by the shining cuckoo. The call of the shining cuckoo is one of the signs of spring as they migrate back to the Chatham’s from their winter homes in the Pacific early in the spring. Like other cuckoos, shining cuckoos lay their eggs in other birds’ nests and on the Chathams this unlucky bird is the warbler. The warblers don’t seem to notice that they suddenly have a huge egg in their nests which hatches into a chick much bigger and more demanding that their other chicks. They just work incredibly hard to feed and raise it as if it were one of their own.

But this year the shining cuckoos have been late in their arrival to Rangatira and we’ve only just started to hear them calling now, over a month later than last year. As most of the warblers have already fledged their chicks, the cuckoos will have problems finding a suitable warbler nest for their eggs. It seems that this year there won’t be any poor warbler parents who will be tired out by feeding a giant and hungry imposter.

Due to their accommodating nature, the Chatham Island warblers were the first birds trialed as foster parents for the black robin eggs when there were really few black robins left in the early 1980s. The researchers knew that taking the eggs away from the robins would make them lay another clutch. They hoped that the Chatham Island warblers would be able to bring up the robin fledglings. But as it quickly turned out, warbler parents are not able to supply robin chicks with sufficient amounts of food (robins are after all almost twice the weight of warbler).

The researchers quickly changed their strategy and chose Chatham Island tomtits as foster parents for black robin chicks. Hence tomtits played a significant role in the survival story of the black robins, and as such went down in the conservation history.

Of rocks and volcanoes - December 27th

We’ve had a few adventures that have involved rocks the last few days with the trip to the Summit and the sleep out on the Rangatira Trig.

So it must be time for me to delve into the geology of the Chathams. The cool thing about geology is that you get layers in rocks and if you drill deeply into them, or they happen to be exposed on a cliff face for example, you can read millions of years of history like you do a book. The modern rocks are at the top and the deeper you go the older the rocks. Well, you can do that if you’re an expert, which I most certainly am not!

Here however is what I do know:

The Chatham Islands are on the Pacific plate, which is the same plate as much of the South Island of New Zealand. The Chathams are also part of what used to be Gondwanaland. Gondwanaland was a great southern continent which over eons slowly split apart to form South America, Africa, India, Antarctica, Australia and New Zealand. The way that the experts know this is because of fossils which have been found here. Continents that used to be part of Gondwanaland have fossils of spores of mosses and fern and pollen from conifers (cone bearing) trees.

Rangatira itself is made up of sediments which accumulated from a volcanic vent which erupted about 4 million years ago. Often volcanoes erupt at the edge of continental plates, but here at the Chathams we are right in the middle of a plate so the volcano was probably what they call a “hot spot” which are areas beneath the earths crust that are so hot that they are able to puncture through a continental plate.

What I can tell you for certain is that there are enough flat rocks on Rangatira Trig so that you can fit four mattresses comfortably and no one is in danger of falling off!