Estimating natural survival of blue whales

Pygmy blue whale (Photo credit: Andrew Sutton, Shutterstock).

Much of the basic biology of blue whales, including the relationship between age and length is still unknown. The best way to age whales remained a mystery until the mid 1950s when it was discovered that researchers could use the alternating layers of light and dark ear wax that formed in the ear canal, known as an earplug, to estimate age.

Earplug data exists for pygmy blue whales (B. m. brevicauda) some Antarctic blue whales (B. m. intermedia), as well as from Eastern and Western North Pacific blue whales (B. m. musculus). This will be the first study to compile all available blue whale earplug data. Using this data, I will fit models to understand the age-length relationship for blue whales, as well as estimate natural survival and age at sexual maturity. These results will provide valuable information that can be used for evaluating extinction risk and population recovery for blue whales.