When J.J. Cardinals customer, Rodger Bloomfield, Linden, MI, was
giving his nest boxes their seasonal cleaning, he discovered two distinctive nests in one
box. The first nest was clearly an eastern bluebirds nest and piled high atop the
bluebirds nest was the nest of a house wren.
House wrens, though small in size, are quite aggressive and will often take over even
an established nest as is shown here:
1) The nest as first seen;
2) The nest being broken down revealed eggs characteristic of the house wren: mauve in
color with sparse cinnamon speckles;
3) Upon closer inspection 4 bluebird eggs were found;
4) The wren may have had as many as eight eggs and only five hatched or perhaps the wren
abandoned the nest site also. Thank you for providing this interesting series of
photographs Mr. Bloomfield.