
My research expedition to Antarctica began with a study of three species of penguins - the Adelie, Chinstrap and Gentoo penguins.
I was one of 23 undergraduates from City University to go on the 21-day expedition to Antarctica, which took place between December 2013 and January this year; it was the first such venture carried out by a Hong Kong university.
I wanted to see how penguin parents protect their chicks in an environment of extreme cold.
In 2012, researchers at The State University of New York at Stony Brook, in the US, found that the number of Adelie and Chinstrap penguins has fallen by almost 60 per cent and 50 per cent, respectively, since 1986.
Man is largely responsible for this drop in population. Global warming influences the natural food chain, which affects the number of penguins that survive the harsh Antarctica conditions.
Warmer sea temperatures are not so good for growing algae, which is one of the main foods eaten by krill. These small, shrimp-like creatures form an important part of the regular diet of whales, seals and penguins.
The algae normally grows on the bottom of sea ice. In the spring, as the ice melts, the algae is released, and krill feed on it. But because of global warming, there is less ice - and less algae growing on it.
If krill can't eat, then there are fewer krill for penguins to eat. This vicious cycle disrupts the entire food chain in Antarctica.
The global ban on hunting whales has led to a rise in the number of some types of whales. This has caused its own problem.
Whales and penguins both eat krill, but whales must eat a lot more to survive. With fewer krill, fewer penguins reach adulthood.
The only way to stop the extinction of penguins and other precious creatures is to conserve our natural environment - and change our behaviour. Our trip to Antarctica made it clear to us all.