Bird-watching usually entails hunkering down in bushes with a pair of binoculars and spying on birds from a proper distance. Watching birds from space, however, is a whole other thing entirely.
Scientists are now using satellite imaging to count and keep track of members of endangered bird populations. These high-resolution images allow scientists to have an idea of how many northern royal albatrosses there are. This marks the first time that scientists have monitored a species on Earth from space.
The northern royal albatross is an endangered species that nests on top of sea-stacks near Chatham Islands in New Zealand. Sea-stacks are column-like rock formations that tower over the water along coastlines. Thus, the albatross nesting sites on top of the stacks aren't easily accessible, to say the least. Any attempts to visit the nesting sites are not only expensive, but also potentially dangerous.
However, these albatrosses are certainly worth the effort of studying. Northern royal albatrosses are large black and white sea birds with a wingspan that reaches 10 feet. They have also faced threats that decimated their population, leading to their endangered status. Commercial fishing has impacted the birds' food source, while storms can affect nests and breeding success as well.
These albatrosses are certainly large, but are they actually be visible from space? After all, that's quite a distance. This is where the DigitalGlobe WorldView-3 satellite comes into play. When people describe images from this satellite as “high-resolution”, they actually mean “super high-resolution”. The satellite can capture images of features as small as 30 centimeters across.
Thus, the satellite will certainly be able to capture images of northern royal albatrosses, since adult birds are about a meter long. Still, the birds only show up as white pixelated dots that stand out in their surroundings. Scientists count these dots to get an idea of how many of these albatrosses there are.
A 2009 manual count reported that there were 5,700 albatross nests. The satellite images reveal that only about 3,600 nests exist today. This is lower than the count that the scientists were expecting. Either the northern royal albatross population is in decline, or the birds are just having a bad year.
It would have been better if scientists had been able to keep a closer watch on the birds, but doing so is quite complicated. It's not often that bird-watching can get so difficult. Scientists can climb the rocks, but that's really easier said than done, not to mention dangerous. They can also take a plane there, but planes are infrequent and trips to the stacks are at the mercy of the weather. Dr. Paul Scofield, one of the authors of the study, once had to wait for an entire month for clear weather to safely fly out to the stacks.
Taking satellite images isn't quite as complicated. Scientists would have to wait for clear skies in order to capture images, but that's far simpler in comparison. Of course, there's still something to be said for traditional bird-watching techniques, but certain situations call for ingenuity.
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