Eagle Egg-Laying Lowdown

Nora Wagner, Duke Farms

In a wicked lightning storm, it’s really tough being the tallest tree in an area surrounded by flat land. It’s good for Bald eagles, but not so good for video and camera equipment. Even with lightning and surge protection, the cam takes a beating whenever a bad storm rolls through Duke Farms like the one two weeks ago.  After troubleshooting and systematically replacing parts, we finally were able to get the cam back on the air. We let out a sigh of relief… and within a nanosecond, one word escaped our lips…”eggs?!”

The nest does not have eggs yet. What does this mean? We were bursting with questions, so went straight to the source of all things Bald Eagle in New Jersey: Biologist Kathy Clark from the State of New Jersey Fish and Wildlife’s Endangered and Nongame Species Program (ENSP). Here’s a summary of the exchange:

Q: Kathy, it looks like we’re pretty late on the eagle egg laying, although the latest egg in years past was laid on 3/22 in 2005. At what point does one make the observation that it looks like the eggs will not be laid this year?

A: Only time will tell, but March is definitely the deciding month.  Getting a late start, or laying a second clutch after the first fails, usually result in lower than average nest success.  If they don’t lay any eggs by the end of March, they are not likely to nest this year.  

Q: We’ve been reading the yearly NJ Bald Eagle ReportIs the technical term for this no egg situation “unsuccessful”? what’s the difference between “unsuccessful” and “failed”?

A: Both those terms refer to a nest that is active – eggs are laid.  When a pair is present at a nest but does not lay eggs, we call it territorial. That’s the category the Duke Farms nest will be in if they don’t lay eggs. 

Q: Just because they didn’t lay an egg this year does not mean that it’s going to trend this way, correct? There’s still hope for next year, right?

A: Correct.  It appears there are two things happening:  a territorial battle that has gone on longer than usual, and the time required for pair bonding between the new(?) female and the established male. 

Q: It’s pretty late this year if they continue to lay an egg. Are eagle egg laying times trending later or earlier or do they pretty much the same time each year?

A: I don’t think we have any significant trend either way.  As the population grows, we have a broader range of initiation. Picture a bell curve, with the majority of nest initiations in the first-second week of February, with the earliest in the first-second week of January and the latest in mid-March.  Established pairs tend to begin around the same date every year, but a change in mates (with or without territorial battles) will often result in a change in date. 

So, there you have it – we still have a chance for eggs this year. A chance that is decreasing by the day, but it’s still there. Let’s hope!

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