Stranded Humboldt Penguins Spheniscus humboldti with Bilateral Blindness along Chilean Coasts

Bilateral blindness is an important cause of mortality in penguin chicks. However, this pathological condition remains little explored for the endangered Humboldt Penguin Spheniscus humboldti. Here, we present the first spatiotemporal dataset detailing young Humboldt Penguins having bilateral blindness. Information was gathered from birds found stranded along the coast of continental Chile over a ten-year (2011– 2021) period. We present a number of cases analyzed by geographical distribution, sex, body mass, and season. Preliminary analysis shows that 73.3% of cases were concentrated along Chile’s central coast. Only 17.1% of individuals were sexed, and the distribution was slightly skewed in favor of males. Two temporal peaks were identified (2015 and 2019) in which slight decreases in body mass were observed. The highest incidence occurred in summer. This dataset will contribute to the understanding of the spatiotemporal mechanisms associated with bilateral blindness in Humboldt Penguins, a condition that can be related to pollution, climatic, and conservation issues.