Fledging of Leach's Storm-Petrel chicks from Gull Island

We used passive integrated transponder (PIT) tags to track the exact time and date that Leach's Storm-Petrel (Hydrobates leucorhous) chicks fledged from their burrow. The data included here are the last read for each of 123 chicks tracked in 2017, 2018, 2021, and 2022 on Gull Island, Witless Bay Ecological Reserve, Newfoundland and Labrador, Canada. We also include morphometric measurements of each chick that was banded and tagged for this study. Methods Data were collected using a custom-built passive integrated transponder (PIT) system. When a tagged bird passes through the receiver placed in the entrance of the burrow, the system records the date, time, and identification of the bird. Morphometric data including weight and wing chord were collected by researchers at the time of chick banding. Chicks were weighed either on a kitchen scale or with a 100 g Pesola scale. Wing chord was measured with a wing ruler either to the tip of the pin feather or to the end of the skin if chicks did not yet have feathers.