Tag Archives: Brood Patch

What is a brood patch?

March 30, 2018: Mrs. North's brood patch

This flashback blog was originally published on February 16 of 2017. Since we’re looking forward to eggs at all of our nests, it seems like a good time to discuss the brood patch – a result of the many hormonal changes that our eagles are experiencing as they come closer to laying eggs.  Press the arrows to view both of the eagles. Robin Brumm and Debbie Fulton got great captures of brood patches from the North Nest (Mrs. North, 2018)

Nest chronology: Egg timing!

Second egg for the Decorah Eagles!

This  blog was originally published on Tuesday, March 20, 2018, to answer questions about egg-timing. It 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