In 2011, we observed many dead birds on the cliffs when we arrived at the colony. At that time, the most experienced observer (K.H. Elliott) considered that the density of mosquitoes was the greatest he had seen in 10 years of visits. On our study plots, we observed a minimum of 22 carcasses ci out of 878 breeding birds (2.5%).
Researchers found unusually high bird mortality upon arrival, signaling a potential environmental or biological disturbance that year.