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Friday, April 19, 2013

Little bird in a big ocean

In the black hours of early morning, a tiny bird emerges from its shallow burrow on the top of a wind-swept rocky island and launches itself out over the wild Pacific Ocean. This female Cassin's auklet is not much to look at – barely larger than a robin and considerably less colourful, with only a tiny white eyebrow as a marking. She has been described as a 'flying tennis ball', built more for diving than for flying, but she has a long way to go to find food for her chick. While her mate rests for the day, she takes her turn at flying out to the edge of the deep water, a one-way trip of up to 100 km. It will be dark again before she returns from her exhausting flight with food for her young safely tuck away in a special pouch in her throat.

The food in question is tiny plankton more commonly known as krill – the same food source that helps sustain massive humpback whales. The continental slope or 'drop off', where the ocean plunges to over a kilometer in depth is an ideal place for such a meal. Cold, nutrient-rich water wells up from the ocean floor each spring to meet the sun, resulting in massive blooms of plankton. It's no accident that Cassin's auklets chose to nest on the Scott Islands, as they are some of the few safe places to nest within flying distance of these rich waters. In fact, the tiny islands are home to almost two million of these birds, over half the world's population!

The larger and brighter the krill that the tiny bird can find, the better, as these provide more energy for her growing chick which have just over a month to grow before they leave their burrows. But there are many dangers in these waters. Tiny, brightly-coloured pieces of plastic may look like food to the mother bird, who will bring them back to her young. Not only do they take up space in her pouch that could otherwise be filled with krill, but they do the same in her chick's stomach, robbing the chick of the nutrients it needs to grow.

Ships that travel through areas where great flocks of auklet moms feed can scatter them, causing birds to waste valuable energy. But these ships hold a far more deadly risk for the little bird: oil. It doesn't take much – less than a drop to destroy the waterproof coating on her feathers her only protection against the frigid waters of the north Pacific. A bird her size would die of cold in a day once her feathers became oiled. One spill near the Scott Islands could easily wipe out a third of the world's population of these birds.

And last, but not least, there's the larger man-made problem of climate change. Years when water temperatures are warmer in the spring have proven to be disastrous for these birds in particular, as their plankton of choice (large copepods) come to the surface for a very limited time. If these copepods aren't around when the chicks need them most, they are far less likely to survive. In fact, the Cassin's auklet population on their main colony, Triangle Island, has declined by 40% over the past 20 years.

Last year was a good one for our mom and her chick survived. As the waters of the north Pacific warm and the bad years become more common, these tiny birds need all the help they can get.

But it's not all bleak for these birds. Over the past few years, the Canadian Wildlife Service has been in the process of setting up a marine National Wildlife Area (NWA) that covers much of the waters around the Scott Islands, the goal of which is to preserve the ocean ecosystem that the birds need to survive and manage the risks posed by human activities. You can read more about this area and its proposed regulations here.

The NWA has the potential to provide meaningful protection for these birds, but there are still some areas where it could be improved:
  • Improving monitoring and compliance of oil pollution is an important step, but with upwards of one third of the world's Cassin's auklets vulnerable, the risk of even a small spill is unacceptable. Large ocean-going vessels like freighters should be required to avoid the areas where these birds are known to feed during the breeding season when they are concentrated in these areas. 
  • The birds are here because of the fish and other creatures they rely upon for food. Stronger measures are needed to protect forage fish in the waters around the islands from industrial activity.
  • Central no-take areas, closed to all types of extraction should be set up as an insurance policy for the rich and productive ecosystem that the birds call home.

Living Oceans Society continues to work with the Canadian Wildlife Service to develop a management plan and identify research priorities for the Scott Islands. Please help support our work – Donate today!

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