Diurnal Time-Activity Budget of the Common Loon (Gavia immer) in Northern Michigan

Abstract

Animals must navigate trade-offs in many areas, including how they spend their time. These trade-offs can be measured with time-activity budgets, which can vary between species and within them. In July of 2021, I collected observational data on the common loon (Gavia immer) at Douglas Lake in Pellston, Michigan primarily during morning and evening activity time periods, with some data collected during afternoon counted toward overall activity budget, and analyzed differences between these periods, particularly with regards to foraging behaviors. I found that loons were far less likely to forage during the evening (7%) rather than morning (55%), and that the most common activity during the morning period was diving, while the most common activity during the evening period was resting. Knowing the activity patterns and foraging habits of common loons can help researchers protect the common loon, which is a threatened species in Michigan, by helping to predict how they may be impacted by environmental change.