Climate Change Increases Reproductive Failure in Magellanic Penguins
Figure 4
Storm mortality (observed and predicted) in Magellanic penguin chicks, by nest type, age, and rainfall.
Mortality increased with higher rainfall, but depended nonlinearly on chick age. N = 28 years, 2482 chicks alive during a storm; 206 died of exposure. Top panels: A & C are the observed percentages of chicks that died from age 0 to 55 days for 4 levels of rain. (A) Bush nests: 24 of 44 chicks died in 4 storms with >45 mm rain. 59 of 138 chicks died in 4 storms with 40–45 mm rain. 20 of 47 chicks died in 3 storms with 20–25 mm rain. 40 of 215 chicks died in 14 storms with 10–15 mm rain. (C) Burrow nests: 4 of 10 chicks died in 4 storms with >45 mm rain. 7 of 28 chicks died in 4 storms with 40–45 mm rain. 0 of 16 chicks died in 3 storms with 20–25 mm rain. 6 of 60 chicks died in 14 storms with 10–15 mm rain. Bottom panels: B & D are the predicted probabilities of a chick dying in a storm. Probabilities were calculated from the best logistic regression model (lowest AIC) with age, precipitation, and low temperature standardized plus age squared and interactions. Low temperature and its interactions were held constant for these simulations. (B) Bush nests. (D) Burrow nests.