Somebody dumped a few goldfish into a Boulder, Colorado lake a while back, and the population subsequently exploded into the thousands, to the detriment of native species. As Colorado Parks and Wildlife officials dithered about, debating whether to deploy electroshock or rotenone to get rid of the goldfish, actual wildlife professionals swooped in to take care of the problem.
The biologists that monitor the lake were out taking samples of fish there this week and saw that the number of goldfish dropped off significantly. "I don't think any of us would have thought in just a couple of weeks pelicans would have cleaned the whole thing up," she said.
But the goldfish are easy pickings for the big American Pelicans; native species are a lot harder to spot. The smarter goldfish have noticed that a few thousand of their closes friends are disappearing, and so they've taken to hiding out in patches of reeds near the shore. Ultimately, however, that's unlikely to save them because the water there is shallow, making it even easier for the pelicans. Hiding may be a good effort, but those flashes of bright gold among the reeds simply indicate to the birds that the buffet is now open.