Miranda - mistnetting

The birds flying in at dusk - Miranda

Last weekend we made a journey up to Miranda to do some mistnetting over a couple of nights. The main goal was to catch Godwits and Red Knots to collect blood from the juveniles that had overwintered in New Zealand rather than migrating north to the Russian/Alaskan breeding grounds. These birds would then be used as a comparison group to the adult godwits and knots that are due to arrive back from the breeding grounds this month. We aim to catch some of these birds soon after their arrival, again collecting blood, to look at their physiology such as amount of muscle fatigue. While not specifically for the project I'm working on we did take the opportunity to get samples of any red plumage that birds had on them.

As you can see from photo, it was a beautiful evening on the first night but perhaps too clear and the high tide a little too early as the birds flew over to the stilt ponds just prior to total darkness. As a consequence many avoided the mist nets. Consequently, our catch of godwits was low, just the one. We did catch half a dozen red knots and a huge number of South Island Pied Oystercatchers (SIPO) which we didn't particularly need for the study, but banded for records. On the second night the godwits showed their superior intelligence and figuring we were up to something, didn't come into the stilt ponds at all. Still plenty of SIPO though, even a recapture from the night before! This did mean I had the opportunity to upskill on my banding with the fine teaching of Gillian Vaughan. Always good to be the field!

Me banding a SIPO

Bird Photography

One of things I did part way through this fellowship was purchase a Canon 450D camera so I could get better at digital photography. This combined with Phil's gorgeous f5.6, 400mm lens has allowed me to learn a lot about photography and take some great photos. As a kid I always dreamed of doing bird photography and now this year, for the first time, I've really been able to get my teeth stuck into it. Particularly so in Alaska where a colleague Murray Potter, who is an excellent photographer, gave me lots of practical advice on white balance options, ISO levels and so on. It's been one of the most satisfying aspects of the year. This complimented the evening photography workshops I did with Bin Trinh, one of Palmy's best photographers. Now I'm always looking for opportunities to photograph birds. Even the other day, while I was out with friends down Cape Palliser, I was able to have a go using my basic 70-300mm lens and end up with a couple of nice shots of spotted shags. Now I need to save my money big time, so I can improve my lenses and continue getting some great shots next year when my access to such a nice lens disappears.

Alaska - the contrasts

One skinny godwit, Alaska

For my final reflection on our recent work in Alaska I can't help but marvel at how godwits have to adapt so quickly to such radically different habitats, the tundra being so different from the inter-tidal flat in New Zealand. These contrasts struck us regularly:

- the wide open grassey tundra, miles from the coast, compared to the sandy/muddy inter-tidal flats and the obvious associated change in diet. The birds we saw were mostly eating berries, compared to polycheate worms and other invertebrates in NZ.

Australian bird (orange flag) eating berries in Alaska.

- feeding is determined by tide cycles in New Zealand, birds getting to feed on low tides, yet in Alaska feeding depended, at least for breeding pairs while we were there, on being able to get off the nest. We went with assumption of 12hr shifts, though we had no strong evidence of this. Other failed breeders of course could eat as they wanted.

- birds in NZ congregate together, whereas on the tundra they were largely isolated pairs, possibly kilometers from the nearest godwit. Failed breeding birds did start congregating towards the end of our stay however.

- they shift from NZ cycles of night and day, to 24 hours daylight

- birds had to deal with entirely different species around them, long-tailed jaegers contrast massively to knots, gulls and other birds from NZ. Godwits would be regularly seen beign chased by, or chasing jaegers. One thing that surprised us though was how the majority of godwit nests we encountered were in close proximity to a jaeger nest!

Overall, no matter how you look at it, you can't help but marvel at these amazing birds. Not only for their staggering migrations, but also for how they can cope so well in such contrasting environments.

Alaska - the nests & chicks

While wandering across the tundra on the hunt for godwit nests we would regularly stumble across nests of other birds. Often this discovery arose following the heart-stopping flush of bird from the nest as we stepped only centimetres away. Ptarmigan often gave the most dramatic flush from the nest. Nest discoveries sometimes proved useful for other researchers in the area at the time, such as those working on Short-eared Owls or Pacific Golden Plovers. The size of a clutch would vary - all Godwit nests we found had 4 eggs, long-tailed Jaegers 2 eggs, but Ptarmigan nests typically had over 10 eggs, the largest I found had 14. There was also a variety of nest type and colouration of eggs. Here's a few examples

Ptarmigan Nest

Godwit Nest

Short-eared Owl Nest

We were also fortunate enough to still be around as the chicks hatched. It was always a delightful sight seeing a chick bumbling its way across the tundra, in the company of the adult or hunkered down on a nest.

Short-eared Owl

Of particular interest was the fact that due to the abundance of voles and lemmings the clutches of some birds, such as Rough-legged hawks, was unusually large. In the photo below you can see a picture of a Rough-legged hawk chick, one of 6 in the nest. According to Ted Swem, a biologist who has been studying rough-legged hawks for 25 years, the typical clutch is 2-3. He had seen only two clutches of 6 in the past 25 years.

Alaska - the other wildlife

So there's no denying that one of the major perks of being in Alaska was being able to see such amazing wildlife every day we headed out into the field. While the bears stayed at a comfortable distance, I did find myself wishing for a closer encounter (though not too close!). Winning us over the most were the Musk Ox. We saw them every day, with one exception, and delighted in observing them with their young.

Reindeer were a common site in the area and we were told by a local Inupiat how they would round them up using helicoptors and remove their antlers for sale to overseas markets, a valuable source of income for the indigenous communities. The Red Fox we saw were few and far between, but we did encounter depredated nests (why not predated one asks?) which could have fallen victim to a fox visit.

The Arctic ground squirrels were great little companions, popping up in all sorts of places as if to say Hi. I love New Zealand and I love our birds, but I sometimes wish the country had evolved with a few mammals present so we could have our own encounters in the bush, as they really add to the whole experience out there. I'm not sure our introduced possums, deer & pigs cut it I'm afraid. That said, we probably wouldn't have such iconic birds like kiwi, kakapo and takahe had that been the case. I suppose it means I just have to keep travelling!

Alaska - collecting data

During our time in Alaska, the focus was on catching male Godwits, such as this gorgeous male with the most stunning breeding plumage. Unfortunately, despite a number of treks across the tundra to this male's breeding area, we never managed to catch him. He was just too clever.

However, of the ones we did catch we recorded typical data such as mass, bill length, wing length, and plumage details. We also collected feather samples to analyse for melanin content and to score the degree of wear.

Before releasing the birds we would add Aplha numeric flags and metal bands so they can be identified in the future, hopefully this summer back in New Zealand! So keep an eye out for J6, J8, J9, K0, K1, K2, K3 and K4, coming to an estuary near you soon.

Alaska - the catching

As you can see from the photo below, the Alaskan tundra is a vast expanse of low lying vegetation, pocky mounds, typically moist and below which lies a layer of permafrost. In this vastly different habitat from the inter-tidal mud flats, godwits nest... somewhere. We had to find that somewhere. Our job had four key steps: 1. Find the birds. 2. Find the nest 3. Catch the birds on the nest 4. Process and release the birds. However, both step 1 and 2 required hours upon hours of work each, mixed with a large measure of good luck. Once we had established typical "Godwit habitat", finding the birds became less problematic, but finding breeding birds was always a challenge. We needed birds on the nest to capture because Godwits typically sit tight on the net and don't flush until a person is remarkably close, in fact, in all cases we could lower the net over the bird and it would stay on the nest!

Locating the nest typically involved relying on viewing a nest exchange (where the male swaps with the female to incubate the eggs, or vice versa). Working on the assumption of 12 hour shifts we would observe foraging individuals to work out schedules and predict when an exchange might occur. Sometimes this worked perfectly, other times not at all... maybe the 12 hour shift idea was a good assumption, maybe not? Once the nest was located however, the next steps of catching and processing the bird could be completed within an hour.

The photo above shows Jesse and I taking the net to lower over a Godwit. The photo below is of a female Godwit still on the nest, look carefully and you can see the net at the top of the photo!

Once the eggs had hatched, catching relied on an entirely different approach and involved catching the young chicks briefly so that the parents would swoop in and be caught by a mist net being flicked up with perfect timing. We also tried various other strategies, such as using recorded chick calls and decoys (to little effect mind you). All up we caught 9 Godwits and 3 Red Knots. This might seem like small numbers, but it has been known for people to be out for up to 6 weeks and not catch a single bird on the breeding grounds. They can be very illusive.