26, 2007 06:08 PST
Paul et al.:
Since Woodcocks eat nightcrawlers (Lumbricus terrestris), people
me what they ate before nightcrawlers were introduced to this
continent. The answer is Lumbriculus variegatus (note that the
spelled slightly different), which is an aquatic worm native to
North America and common in riparian areas.
Lumbriculus accumulates toxic metal pollution that is present in
aquatic sediments these days, which is why there are so many
metals in woodcocks, which still eat Lumbriculus in addition to
Lumbricus terrestris is probably the best suited of the exotic
to invade riparian areas where Lumbiuculus lives, as long as
alkaline, because it uses Ca to scrub CO2 from their blood under
microaerophilic conditions (<5% oxygen). Nightcrawlers eat
leaves with high
Ca content (ash, basswood, maple), and extract the Ca, and
combine the Ca
with CO2 to form Calcium Carbonate, which they excrete.
survive in microaerophilic conditions such as an aquarium with
oxygenator, for at least two weeks (one of my graduate students
experiment). A nightcrawlers is bigger than a Lumbriculus, so
its a real
treat for a woodcock--a lot to eat for relatively little work.
PS--there will be an earthworm physiology quiz at the next ENTS