I don't have exact dates for VT, but in northern states generally,
nest-building usually happens in January or February and egg-laying soon 
after.  So if your pair is a breeding pair (and they wouldn't be sitting 
close together this time of year if they weren't), they've already started.

Eagle nests are really large, so you should look for one around there 
somewhere.  The ideal spot is near water and deep in the branches of a 
tall conifer just below the crown, so not necessarily easily visible. 
Best if you can hang around that tree you saw them on for an hour or so 
and watch for comings and goings.

Incubation period is around 35 days.

It's a little odd to have both eagles off the nest if there are eggs or 
very young chicks in there, though, so it's possible these guys may be 
behind schedule for egg-laying. (Or maybe they're way ahead and the 
chicks are big enough for the mother to take a break off the nest with 
the male somewhere very nearby?)

You might look carefully for dark edges to the white feathers on both 
head and tail, which would indicate a bird that's not quite fully 
mature.  If that's the case, they may have messed up on the 
nest-building and/or mating and/or laying, or just doing what's called 
"housekeeping," mating, fooling around with making a nest, but pretty 
much just going through the motions a year before getting serious about it.


On 4/2/2016 1:40 PM, Martha Pfeiffer wrote:
> Ruth Stewart and I today saw a pair of mature Eagles,  together,
> hanging out in a tree in Arlington.Information on an eagles breeding
> behavior would be helpful.  When (in Vermont) do eagles start making
> their nest?  What is the time period from egg laying to hatching?
> We'll keep an eye on the area to see if they stay around (fingers
> crossed). Thank you,  Martha PFeiffer, Dorset