Tag Archives: Weather

Bald Eagles, Eggs and Cold Weather

The eggs are warmed and protected by their parents’ bodies and the insulation beneath and around them.

Cold weather often raises concerns among Bald Eagle watchers. Will their favorite eagles keep their eggs warm and dry in sub-zero temperatures and snow? Eagles don’t have central heating or electric blankets, but they have everything they need to incubate their eggs through the worst a Midwestern winter can throw at them: meticulously built nests that aid incubation and withstand winter’s chill, highly vascularized brood patches that transfer body heat directly to their eggs, and remarkably robust eggs.  In short:

How do Bald Eagles stay warm in cold weather?

January 23, 2023: HD sports eye-cicles on a frosty morning in Decorah. An icy fog left everything coated with frost

Each species experiences the world differently and eagles have capacities that are far different from ours. How do Bald Eagles survive an Iowa winter without adaptive clothing and central heat? After a very warm week, temperatures plummeted on Saturday! When I jumped into my car to begin our Golden Eagle Survey, it was 25 degrees. By the time I got home late Saturday night, it was 5 degrees and the temperature was dropping fast! I checked our camera operators’ logs,

Can birds detect severe weather? Storms, cold, and Bald Eagles in winter!

January 2, 2022: Mr. North looks stylish in his wintery down jacket! Subzero temperatures had every one in winter gear today.

Can birds detect severe weather? I’m watching the birds at my feeder as a major snowstorm rolls in. American Golden Finches, Dark-Eyed Juncos, Black-Capped Chickadees, and White-Breasted Nuthatches are decimating my seed feeder, while our resident Downy, Hairy, Red-Bellied, and Pileated Woodpeckers clean out my suet feeder. The feeder action started yesterday. Did our birds know a major storm was on the way? While birds can’t predict long-range weather patterns, they have at least two ways to detect and prepare

Why do bald eagles lay eggs in ice and snow?

Egg-laying Map

Why do the Decorah and Decorah North eagles lay eggs in ice and snow? A lot of you – especially those of you who also watch the Florida eagles – are curious about bald eagle egg timing. Wouldn’t it be better to delay egg-laying until mid-March or early April? We’ll unpack the question by starting with a few facts. An Overview of Bald Eagle Nesting Bald eagles don’t all nest at the same time. In the southeastern United States, especially

Nest chronology: Egg timing!

Second egg for the Decorah Eagles!

This blog discusses the correlation between new mates, temperature, humidity, and egg-timing.  We’ve been getting questions about egg timing. Why did Mom and Dad lay eggs later in 2018? Overall, avian egg-timing in the temperate zone is heavily regulated by the light cycle. As the days begin to lengthen, birds’ gonads swell and produce sex hormones. Around the end of January, our bald eagle pairs switch from infrequent copulation to frequent, highly enthusiastic copulation, putting us on notice for egg