For the first time, humans bring a mammal species to extinction

This is so sad. We've brought many species to extinction, especially in the last decades, because of our way of live and our entrenchment into nature's realm with no regard for other animals' needs, but this is the first time we actually caused a mammal, that is an animal belonging to our own species, to simply disappear:

The Baiji Yangtze Dolphin is with all probability extinct. On Wednesday, in the city of Wuhan in central China, a search expedition, under the direction of the Institute for Hydrobiology Wuhan and the Swiss-based baiji.org Foundation, drew to a finish without any results. During the six-week expedition scientists from six nations desperately searched the Yangtze in vain.
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«It is possible we may have missed one or two animals», said August Pfluger, head of Swiss-based baiji.org Foundation and co-organizer of the expedition on Wednesday in Wuhan. Regardless, these animals would have no chance of survival in the river. «We have to accept the fact, that the Baiji is functionally extinct. It is a tragedy, a loss not only for China, but for the entire world», said Pfluger in Wuhan.
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The fate of the delicate dolphin is attributed to the destruction of their habitat, illegal fishing and collisions with ships. Regarded in China as the "goddess of the Yangtze", the 20 million year old river dolphin was one of the world's oldest species. The Baiji is the first large mammal brought to extinction as a result of human destruction to their natural habitat and ressources.

In the beginning of the 1980s the Yangtze still had around 400 Baiji cavorting in its waters. However, the river dolphin became a victim of China’s rapidly growing economy. A 1997 survey still showed 13 confirmed sightings.
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Alongside the search for the Baiji, the scientists surveyed also the population of the endemic Yangtze Finless Porpoise, and the total was less than 400. «The situation of the finless porpoise is just like that of the baiji 20 years ago», sais Wang Ding, deputy director of the Institute of Hydrobiology Wuhan. «Their numbers are declining at an alarming rate. If we do not act soon they will become a second Baiji», said Wang Ding, deputy director of the Institute of Hydrobiology of the Chinese Academy of Science in Wuhan.

Let's see if we'll be able to spare this other species the fate of the Baiji.