Raptor Resource Project: Bald Eagle and Bird of Prey Cams

The Raptor Resource Project
♡ Donate
🛍 Shop
✉ Subscribe

Tag Archives: Eggs

What Makes Bald Eagles Incubate?

February 23, 2022 RaptorResource

I loved watching Mr. North incubate eggs through today’s snowy weather. He turned his head out of the wind, closed his eyes to protect them from the blowing snow, and fell asleep as the nest rocked gently back and forth. What makes normally active birds like hawks, falcons, and eagles spend so much time sitting on eggs? Hormones, egg production, and broodiness As daylight length increases, birds’ gonads swell. Both sexes produce testosterone, although male birds produce more than female

Why do bald eagles lay eggs in ice and snow?

January 21, 2022 RaptorResource

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

Nothing Goes to Waste

March 16, 2021 RaptorResource

Xcel Energy’s Fort St. Vrain eagles rode the big storm out last weekend. Despite an astonishing twelve or so inches of snow, Ma kept the eggs covered through most of it. Male and female eagles both incubate eggs, but females usually cover the nest at night and through bad weather. A female eagle’s larger body size and brood patch helps her stay still for longer periods of time and apply more heat to the eggs and young beneath her. Unfortunately,

Eagles, ‘menopause’, and a new mate at Xcel Energy’s Fort St. Vrain plant

February 25, 2021 RaptorResource

Has Ma FSV entered ‘menopause’? This blog was going to be focused on eagles and ova, but Elfruler, our original DE lead mod and a long-time chronicler of bald eagle nests, noticed that the male had a band on his right leg, not his left. A new eagle has replaced Pa FSV. If you’d like to learn more about eagles and ova, please read on (TLDR: Ma FSV has not entered menopause). Thanks to Elfruler for her observations and Donna

When will the eagles start laying eggs?

January 21, 2020 RaptorResource

Tik-tok egg clock! When can we expect our eagles to begin laying eggs? If they follow their usual schedules: The Xcel Fort St. Vrain eagles should begin laying eggs in mid-February. Look for laying to start between February 12 and February 21. The Decorah eagles should begin laying eggs in mid-to-late February. Look for laying to start between February 17 and February 23. The Decorah North eagles should begin laying eggs in mid-to-late February. We only have one year of

Peek inside a bald eagle egg: 17 days!

March 20, 2019 RaptorResource

This blog was first published on March 23, 2017. We reposted it to give everyone a peek inside the eggs. As of this writing, there are two eagle eggs in Decorah. We’re not sure whether the oldest or second oldest egg cracked, but we do know that the youngest is about 17.5 days old. What do embyronic eagles look they look like as they develop and grow inside their eggs? Dr. Peter Sharpe from the Institute for Wildlife Studies developed a

Can mice destroy bald eagle eggs?

March 14, 2019 RaptorResource

Eeeek – mice! We’re getting asked whether mice could or did destroy eggs in our eagle nests. Our answer? A guarded “No”. In North America, researchers have found limited predation by mice in the nests of smaller birds, and none in the nests of birds of prey or larger birds. Researchers have been looking at nest predation for a long time. How do nest location, weather, landscape, habitat fragmentation, and predator-prey/predator-predator relationships impact predation rates? Can nest predation be reduced?

Peek inside a bald eagle egg: 11 days!

March 6, 2019 RaptorResource

This blog was first published on March 23, 2017. We reposted it to give everyone a peek inside the eggs. As of this writing, the first Decorah egg is 11 days, 10 hours old, the second egg is seven days, 14 hours old, and the third egg is three days, 13 hours old. What do embyronic eagles look they look like as they develop and grow inside their eggs? Dr. Peter Sharpe from the Institute for Wildlife Studies developed a table

Peek inside a bald eagle egg: 4 days!

February 26, 2019 RaptorResource

As of this writing, the last Decorah egg is 22 hours old, the last Decorah North egg is 9 days, 23 hours old, and the last Fort St. Vrain egg is 12 days, 22 hours old. What do embyronic eagles look they look like as they develop and grow inside their eggs? Dr. Peter Sharpe from the Institute for Wildlife Studies developed a table of bald eagle embryonic development based on work done by Hamburger and Hamilton (1951). While not all

Eggs and cold weather

February 20, 2019 RaptorResource

This blog was first published on Wednesday, February 26, 2014. It has been updated to reflect Mom’s new mate and includes some information about the Fort St. Vrain eagles as well. Everyone was worried about the eggs in Decorah back in 2014. Iowa was facing a polar vortex while Mom was laying and incubating eggs. While there have been other cold years, 2014 was one for the record books, with windchills of -50F when Mom laid egg #2. Given that 2019

« Older Entries Recent Entries »