START YOUR ENGINES
we hover around the spring equinox, get ready to experience the full
joy of our natural heritage. As my son says, "Nature, start your
trip to our woods and stream gave clear evidence of the upcoming transition
to be seen over the several weeks of spring, with its fickleness of
whether to be cold, warm, rainy or windy.
day was on the cool side as we explored the landscape looking for whatever
we could find of interest. Surprisingly, considering the temperature,
we found two small, sluggish harmless snakes and a few lizards under
boards we had set out for just that reason - to find snakes and lizards.
remain inactive during cool weather except on clear days when they can
bask in the sun. But warm-blooded mammals and birds can be active during
cold weather, and reproduction often starts in winter or early spring.
for smaller species is to get ahead of the inexorable advent of warm
weather, when predatory reptiles emerge from cold weather dormancy.
day, my grandson Parker decided he would climb up and check the wood
duck boxes along the creek. These large boxes are nailed to trees facing
the water and have a large circular opening so that ducks can enter,
lay eggs, and incubate them to hatching. A hinged door on the side can
be opened for a look inside.
two boxes led to high fives, because one had 10 wood duck eggs and the
other had 17! The third box had its own surprise. A gray squirrel jumped
out and ran up the tree when Parker opened the door. After feeling around
inside he came out with the second surprise - two eyes-still-shut baby
a warm spell was on the way, and we often find large ratsnakes (which
eat duck eggs) in the boxes, I wondered about this cycle of life phenomenon,
the dynamics of the arms race between wood ducks and ratsnakes. To get
a science-based answer, I got in touch with Bobby Kennamer, a friend
and colleague at the University of Georgia's Savannah River Ecology
described Bobby before as having conducted the most impressive long-term
ecological studies on ratsnakes and wood ducks ever published in the
scientific literature. His field credentials include capturing wood
ducks for more than 35 years and counting nearly 50,000 eggs.
to Bobby, a wood duck hen lays about an egg a day, for about 12 to 14
days. He noted that the box with 17 eggs is "almost certainly the
work of more than one female," whose eggs will be incubated unknowingly
by the first occupant of the nest.
does not begin until a female lays almost all of her eggs, at which
point she sits on the eggs at night. Bobby said, "When the clutch
is complete, full incubation is initiated during both day and night,"
with the female taking morning and evening feeding recesses.
snakes enter the spring-time scene, they patrol woods, swamps and streams
searching for open tree cavities that might have nesting birds or squirrels.
box with a big hole is a well-defined lure for a big ratsnake, which
can eat as many as ten eggs. The hen will fly away, but the snake may
stay in the nest box for up to several days while it digests the eggs.
female wood duck figures out that a ratsnake predator has invaded, "she
will generally abandon the nest, even though there may still be uneaten
eggs remaining in the box."
race is underway, with squirrels and ducks in the starting lineup, but
as soon as warm weather sets in, the snakes won't be far behind, looking
for their first meals. Nature's race track is a lot longer than any
of NASCAR's and a race for us to marvel at as spectators for many weeks.
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