In the 1990s, the Channel Islands off the coast of California were the scene of a devastating environmental disaster. At this point, the island fox, a native carnivore and the undisputed king of these islands, began to disappear at a fairly high rate. And the statistics leave no room for doubt, since at its lowest point, Santa Rosa Island reached only 15 from 1,780 specimens, while Santa Cruz’s population dropped from 1,400 to only 55.
endangered These figures, in a very short time, set off all alarms, as they were literally one step away from extinction. The problem is that it took a long time for researchers to see that the culprit wasn’t climate change or spreading disease, but a strange man-made domino effect.
mechanism. The question was clear: How could thousands of foxes disappear in a few years? And the answer comes from a researcher who pointed out in the early 2000s that a phenomenon known as ‘pig-mediated hyperpredation’ was to blame.
Although it may seem strange, it is understandable, since for decades, ranchers brought pigs to these islands, which went wild and multiplied without control. The problem is that so much food on the islands has attracted a powerful predator from the mainland that has never before been seen on the islands: the golden eagle.
hunter Golden eagles settled on the islands to hunt pigs, but they soon discovered the island fox that also roamed those lands. Foxes, having evolved in an environment where they didn’t have to worry about predators coming from the sky, didn’t develop evasion mechanisms, so they were very easy prey for eagles. And this is where the double genocide begins.
Plan a crash. With the species on the brink of the abyss, authorities had to take action. The first of them involved the removal of golden eagles, organizing expeditions in which 44 eagles were captured and relocated off the islands, which began to restore the fox.
But in addition, the war on pigs began with an eradication program that cost about five million dollars. With this, 5,036 pigs were culled in about 400 days. Thus, the islands were no longer a feeding ground for golden eagles.
to prevent To ensure that this does not happen again and that golden eagles do not return for foxes, their natural competitor, the American eagle, was introduced. These eagles feed on fish and seabirds and are very territorial, so their mere presence makes it almost impossible to dare approach golden eagles.
Recovery. The success was so significant that authorities declared the island fox represented the fastest recovery they had seen for an endangered mammal. And the truth is that the recovery has been very positive, as of today 3,086 foxes have been counted on Santa Cruz Island, while San Miguel has a population of 322.
Picture | Emma Reyneres
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