Directly following the eruption, it was believed that there were no present surviving species on the island. The organisms were either killed or forced to flee as their habitat was destroyed around them. Nearly all of the marine and avian mammal breeding habitat was covered by volcanic ash, including the rookery on the north side of the island for the endangered Steller sea lions that previously resided there. It was not until weeks to years later that species began returning to the island. Approximately 200,000 auklets returned to the island in the summer of 2009, but as their rookeries were still covered with ash, they could not to be used for nesting. Surprisingly enough, sea lions were present on the island up to two weeks after the eruption. Their rookeries had been thickly buried as well, but coastal erosion had cleared them by the summer of 2009. Because of the intensity of this natural disturbance and the almost complete devastation of life on Kasatochi right after the eruption, the island became a textbook site for primary succession. Scientists took this opportunity and started a research project in 2009 to study ecosystem impact and long-term recovery. Their goal was to find the patterns and reasons for the returning of various species to the island. This was a rare opportunity to study this type of succession, as it is not often that data on an area exists after a disaster of this magnitude.