Before I get started, a friend sent me this reference to a new video about Spitzbergen/Svalbard that gives a really good overview of it: http://vimeo.com/37141607
It’s crunch time now in Svalbard. Most of the eggs have hatched and adult birds, of all species, are racing against time and the odds to feed and fledge their young before Winter is upon them. This is truly a beautiful area but it’s also a very harsh one and breeding birds in the high Arctic get only one chance. If they can’t find a mate or a territory, can’t find enough food, can’t dodge, hide from or fend off predators, then their breeding attempt will fail and they will have to wait until next year (assuming they survive) to try again.
You can see the drama being played out everywhere and, as you can imagine, it often isn’t very pretty. Here are some examples:
- the Snow Bunting nest we found contained 5 eggs; four of these hatched, one did not; over time, 4 gaping, yearning mouths dwindled to 3 and, at last count, only 2. Being a nestling in an environment with very limited food resources, requires that you out-compete your siblings for the morsels that your parents bring if you want to survive…whether it results in your siblings’ starvation or not.
- some Barnacle Geese build their nests at the top of the cliffs. When the young hatch, it would appear that theparents lead them to the cliff edge and have them jump to the beach/water below (not unlike a Wood Duck coaxing its young out of a hole in a tree). The long trek around, from the nest down to the ocean, would leave them highly vulnerable to both land predators (in this case foxes) and avian predators – especially Glaucous Gulls. We came upon a family grouping of two adults and 5 goslings huddled close to the cliff edge, getting ready to go. Unfortunately, there was a strong onshore wind with accompanying updraft. Later we saw what we think were the two adults standing on the narrow swath of beach looking back at the cliffs and the boulder field below. They had only one young one in tow. After about 15 minutes, they continued on leaving the other 4 most likely mired down in the deep gaps between the boulders at the base of the cliffs, their downward flight buffeted by the wind.
- Black-legged Kittiwakes are strikingly handsome gulls that often stream by the cliffs in groups of up to 20. They will often travel many kilometers to find the right food to feed to their chicks. Returning over that distance leaves them vulnerable to Parasitic Jaegers which will chase and harrass them until they give up their food. Yesterday the screaming of a kittiwake drew my attention to this drama. It flew very acrobatically to “lose” the jaeger that was in hot pursuit on its tail…literally. The chase lasted for more than five minutes, at which point a Glaucous Gull joined the in just behind the jaeger. This was too much for the gull which regurgitated the copepods it was carrying. But the winner here was the Glaucous Gull, which is much too large for a jaeger to drive off, and which dropped into the water to collect the spoils. For the jaeger and the kittiwake it was a large energy expenditure for no gain – with possible serious ramifications for their young.
- We have sighted at least 3 Glaucous Gull nests within easy reach of the the murre cliffs. These birds patrol the cliff face tirelessly, looking for mistakes (an egg gets knocked off a precarious ledge by another bird taking off) or opportunities (an egg or chick, toward the edge of a group, is left unguarded for a short time by a parent). But there is one gull that is much more aggressive in supporting the food needs of its chicks. It will take advantage of the wind (to hover over a victim) and of a murre’s heavy wing loading (weight to wing area ratio). At what it feels is the right moment, it drops, grabs the adult (we’ve seen by the wing and by a leg) and pull it off the ledge, thus leaving its egg or chick exposed – this is quickly gulped down by the gull. Murres are not agile like gulls or terns; when they lose their balance and come off the cliff ledge, they drop and have to flap vigourously to halt this descent.
They then head out to sea where they can turn and build up the speed they will need to get back to their nest. By this time, the gull has easily swallowed the nest contents and moved on to look for more. (Cindy, who spends much of her day observing murre behaviour, reported seeing the same gull use this method to get an egg and a chick within 5 minutes.) Clearly, the place to be is in the middle of a group, both vertically and horizontally – the eggs and chicks of those on the edges suffer a proportionately higher mortality.
We started banding chicks this past week. We did six – just the tip of the iceberg: over the next two weeks we’ll do a lot. And then, four years from now, we will start looking for these youngsters to return and try to carve out a breeding spot on these same cliffs. The sighting of one of these banded birds will truly be exciting!
This past week we continued to deploy loggers that will track the movements of the adult birds throughout a year of their life cycle. They should tell an interesting story when they are recovered next June. We also, deployed 17 GPS units (and will do another 17 or so this week), which will stay on the bird for about 4 days, at which time we’ll recapture them and remove the units. From these we hope to learn where the birds, that are feeding young, go when they’re not on the nest. Sometimes both parents will be sitting closely while one broods the chick. But more often than not, one of the parents is absent, sometimes for up to several hours. Regularly, when it does return, it will bring a fish for the young one to wolf down. Intuitively, one would think that they are finding these fish in the fjord right out from the cliffs – you can often see groups of them swimming and diving together. But this may not be the case. When I was on Devon Island helping with a Northern Fulmar study, we would see the fulmars zoom down to the polyna to bathe and pick up copepods. But these were not feeding chicks. Satellite transmitters revealed that the parents would travel upwards of several hundred kilometers from the nest to find the food they required. Maybe these murres do the same.
One of the interesting things that we’re doing now is “diet observations”: you sit in a spot where you can watch a set number of nests with chicks and for two hours straight just watch and record the returning adults, noting what kind of fish it is carrying, how big (long) it is, and (if time and speed allow) identify the carrier and the nest it is servicing. It is an incredible thing to watch a small murre chick gulp down, whole, a fish that is longer than it is.
But the Summer is winding down, you can feel it and you can hear it…..or, more accurately, you can’t hear it: bird song, even call notes, is pretty well over (unless you’re right at the cliffs). True silence is hard to come by in our civilization – but sometimes now all you can take in is the wind moving past your ears.
There are (and have been) a wide range of small beautiful flowers in pockets across the tundra. I took pictures of some and asked my good friend Ludo Jolicoeur (who was here last year) to please identify them for me: