Posted by Alvaro Jaramillo (205.134.242.189) on December 26, 2000 at 11:07:11:
Birders:
I don't like this yellowlegs one, partially because in real life
these things are much easier to identify than from a photo. In any
case, it looks like a Greater to me based on the thick bill, thick
legs, lack of peak on hindcrown, etc.
The nighthawk is probably more of a challenge than the yellowlegs in
some respects, but in my opinion it may be more straight forward
The problem is that we get precious little experience looking at
nighthawks so we are not well versed in what to look for. But in
reality there are some tangible differences you can use that
are reliable in separating the nighthawks. What I concentrate on is
the primary feathers. First of all Lesser Nighthawks have short and
rounded wings, compared to Common. This translates to a slightly shorter
primary extension but more importantly an outer primary that is
shorter than the next one in. So on the folded wing of the Lesser
Nighthawk you will see 4 primaries beyond the tertials, since the
outermost is hidden. On a Common Nighthawk you see 5 primaries past
the tertials, the outer one just a bit longer than the next longest. On
the mystery bird there are 4 primaries visible, and you can see that the
outer primary on the near wing is shorter and partially hidden due to the
manner in which the bird is holding its wing. Also check out the wing
patch, it is buffy-white and under the tip of the folded tertials. The
patch on a Common Nighthawk tends to be white and is either entirely
hidden by the tertials or just visible below their base. The buff colour
of the wing patch along with the throat pattern of this bird are perfect
for a female Lesser Nighthawk. Finally, the bases of the primaries of a
Lesser Nighthawk are patterned with buff spots while they are all dark in
Common Nighthawks. So looking at the wing of our mystery bird just basal to
the wing patch you can see a second buff patch, this is the first row of these
buff spots and should be diagnostic for Lesser Nighthawk. Note that most of
our nightjars have these spots all the way out to the tip of the primaries
except in the Paraque. This is a really good way to ID a perched Paraque in
your headlights or flashlight when it is not making a sound, look for entirely
dark primaries. Tail length can be a lot harder to see. Anyway getting back to
the nighthawk, Antillean can be separated by many of the same features used
to differentiate Lesser from Common since its wing shape and primary pattern is
more similar to Common than Lesser. On perched Antilleans I have seen, they
look very golden above (but I gather that this is morph related) and they have
contrasting grey tertials.
Happy Holidays,
Alvaro