202 | Chapter 10
Remote sensing from satellites is already able to detect seabird colo-
nies. In 2012, Pete Fretwell and colleagues from the British Antarctic
Survey published a paper that was justifiably, if a tad grandiosely, titled
‘An Emperor Penguin Population Estimate: The First Global, Synoptic
Survey of a Species from Space.’^32 Examination of satellite imagery of
the entire Antarctic coastline had revealed four new, and hitherto un-
known colonies, and confirmed the location of three previously sus-
pected sites. This elevated the total number of known Emperor Penguin
breeding colonies to 46. Arguably the more complicated part of the
study was using the images to estimate the number of birds since the
penguins were often tightly clustered and not distinguishable as indi-
viduals, unlike the birds in the drone photographs. To overcome this
hurdle, ground- truthing was necessary. At a small number of colonies,
the relationship between the number of penguins actually counted and
the ground area their huddle occupied was established. This enabled the
number of penguins in other clumps extending over various areas, as
measured from the satellite images of the different colonies, to be cal-
culated. And, wonderfully, a global estimate of 238,000 breeding pairs
emerged. This total represented a near- doubling of the previous esti-
mate and was celebrated worldwide from Sky News Australia to the
Wall Street Journal.
With the principle proved, similar techniques have been applied to
the other penguin of the far south, the Adélie Penguin. How exciting
if the technique could be extended to other species, like the Antarctic
Petrel, where the number of birds encountered at sea cannot be recon-
ciled with the number at known breeding colonies, raising a strong sus-
picion that there are colonies yet to be discovered. Also under investi-
gation is the idea of using satellite imagery to count the population
of the rare Short- tailed Albatross on the Senkaku Islands. Because of
territorial disputes between Japan and China, the islands have been off-
limits for ground- based counts for over 10 years.
Another possibility is to use aerial reconnaissance to discover colo-
nies of species whose nesting grounds remain totally unknown. One
such is Hornby’s Storm Petrel, mentioned earlier in the chapter. Mum-
mified chicks have been found in the supremely arid Atacama Desert of