Photo source: © Sean MacDonald for BBC / via bbc.com
Excerpt from bbc.com
Ecosystems which have never been seen before are being accidentally created by humans. They offer a stark look into the nature of tomorrow.
Venture deep into the forests on O’ahu, Hawaii’s third largest island, and you’ll find yourself threading through a dense understory of richly scented pepper, cinnamon and guava trees.
“It’s beautiful,” says Corey Tarwater, an ecologist at the University of Wyoming in the US who began researching O’ahu’s ecosystems in 2014. Sounds like the “cheww-chewww” song of the pale green warbling white-eye and the chattering, almost electrical call of the red-billed leiothrix surround you. “There’s really neat lizards around,” adds Tarwater. “There’s these highly structured forests with these amazing tropical plant species.”
For hikers setting out on O’ahu’s mountain trails, these are thrilling wildernesses within easy reach of Hawaii’s capital, Honolulu, says Tarwater. Yet nothing is quite as it might seem, she adds. “You wouldn’t know unless you study them, but if you walk around any forest around Honolulu, there’s not going to be one single native plant species there.”
O’ahu’s lowland forests are now almost entirely devoid of the plants and animals that grew here for millions of years before the arrival of humans. Settlers brought extinctions by cutting down trees to make farms and introducing voracious predators and disease-carrying animals. Today, these tropical forests are a tapestry of non-native species introduced from every corner of the planet: Brazilian peppertree, Indonesian cinnamon and roseleaf bramble from the Himalayas and Australia. Most of the animals, including all the birds that Tarwater mentioned earlier, are also alien.