Monthly Archives: January 2015

Incubation Duties

Rolling the eggs

Rolling the eggs

Our parents are doing their usual good job of protecting their three eggs from the elements and any predators (crows, vultures, owls) that might become interested in the nest if the eggs were left alone for too long.

Our parents share in the incubation duties, which require that the eggs be kept at around 99.5° F in order for the eaglets to develop properly inside the shells. Although both parents perform this duty, the female is on the nest the most and she seems to be the one on the nest at night. The female is about a third bigger than the male, although sometimes this is hard to see unless they’re right next to each other. I usually look to see if the parent seems to be about as long as the central nest area, and if it is, then I assume it’s the female.

Incubation duties include not only protecting the eggs and keeping them warm, but also rolling them about once an hour. Rolling prevents the developing eaglets from getting stuck to one side of the inner shell wall, and it also ensures that the heat is applied evenly to the egg. Each parent has a brood patch, which is a featherless area on their chest that they press against the eggs to apply their body heat directly to the shells.

When rolling the eggs, the parents have to be careful that they don’t puncture the shells with their very sharp talons. If you watch carefully, sometimes you can see the parent roll their talons in before touching the eggs. Considering that an eagle’s talons are its most fearsome weapon (they can puncture a human hand), it’s always amazing to see them being so gentle when touching the eggs.

For anyone who has watched our Eagle Cam in the past, you know that our parents like to perform a little “ballet” during incubation season. When the non-incubating parent wants a turn on the eggs, they often drop something on the back of the seated parent — pine needles, grass, etc. — and then they stand there until the seated parent finally gets up. We saw an example of this yesterday, and it worked, like it usually does!

The Changeover

The Changeover

Until next time,
Lisa – webmaster
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Categories: blackwater nwr, eagle cam, eggs | Leave a comment

Welcome to the 2015 Season!

Three eggs on 2015 Eagle Cam

Three eggs on 2015 Eagle Cam

We want to welcome everyone to the 2015 Blackwater NWR Eagle Cam season!

Blackwater National Wildlife Refuge is on the Eastern Shore of Maryland and is a unit in America’s National Wildlife Refuge System, which is “a national network of lands and waters for the conservation, management, and where appropriate, restoration of the fish, wildlife, and plant resources and their habitats within the United States for the benefit of present and future generations of Americans.”

The Blackwater NWR Eagle Cam is a project of the Friends of Blackwater. The Friends’ group is comprised of volunteers who support the Refuge and the U.S. Fish and Wildlife Service, which oversees the Refuge System. Our volunteers help staff the Visitor Center, run the Eagle’s Nest gift store, maintain trails, assist with events and biological surveys, and maintain the Eagle and Osprey Cams (as well as this blog, the cam galleries, and the social media channels). If you’ve enjoyed our cams, please consider supporting the Friends.

As for our Eagle Cam, it’s been online since late 2004 and is located about 80 feet high in a loblolly pine tree on Refuge property. Our camera has always been pointed at the same nest, and every season we’ve had at least two eggs hatch. You can see the galleries from our previous seasons on our Cam Central page.

If you’ve been watching our Eagle Cam page, you know that we have three eggs for the 2015 season. Here is our current scorecard:

  • 1st egg laid: 1/7 (earliest we’ve ever seen an egg on the Eagle Cam)
    Possible hatch: 2/11-14
  • 2nd egg laid: 1/10
    Possible hatch: 2/14-17
  • 3rd egg laid: 1/13
    Possible hatch: 2/17-20

Bald eagle egg size

This year I added a range of hatch dates because even though the average incubation is 35 days, our pair sometimes goes a bit later than that, so I decided to show the 35-38 day range. Just keep in mind that the incubation time can vary — especially for the second and third eggs.

On our Friends’ Facebook page (which you should visit to see many excellent photos from the Refuge), a couple folks wondered about our track record with three eggs. A normal clutch size is two to three eggs, and in the past we’ve had two successful seasons with three chicks fledging (2005 and 2011). In 2013, we had three chicks hatch, but the third chick hatched about five days after the second chick (a late hatch) and the chick never looked strong and died shortly thereafter. In 2014, we had three eggs, but the third egg never hatched — which is the first time we had a dud egg. It’s impossible to know for sure since our adults are not banded, but we wondered if the failure of these third eggs in 2013 and 2014 was possibly related to an aging female adult.

But for the 2015 season, we’re hoping that the third egg is a good one and will hatch within a reasonable amount of time. Bald eaglets are the fastest growing birds in North America, so even a few days between hatchings can put the younger chick at a big disadvantage, since their siblings will be a good bit bigger and will make it harder for the younger chick to get its turn at meal time. But third chicks can survive, and our parents are excellent providers.

We’ll be updating our Eagle Cam gallery in the next day. Thanks to those who have sent in photos. If you’re new to our cam, you can learn about submitting photos here.

Until next time,
Lisa – webmaster
Support the Blackwater Cams
Contact Us

Categories: blackwater nwr, eagle cam, eggs | 2 Comments

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