The beautiful Black Swallowtail has adapted well to
suburban and urban environments. Sometimes, eggs are even laid on parsley growing on the terraces of high-rise
apartments. This hilltopping species is fond of clovers as nectar sources, and tends
to stay closer to ground than other swallowtails. Males find females by
'patrolling' small territories. Swallowtails often have a large amount of
black coloration. Black is useful because it absorbs heat better than other colors
and helps the butterflies warm up.
The Black Swallowtail caterpillars feed on herbs in
the carrot, or Umbellifer family (Apiaceae). They are especially fond of the leaves,
flowers and young seeds of cultivated umbellefers like Parsley (Petroselinum crispum),
Fennel (Foeniculum vulgare), Lovage (Levisticum officinale), and Carrot
(Daucus carota). Other native or naturalized plants used by the Black
Swallowtail include Water Hemlock (Cicuta mexicana), Water Dropwort (Oxypolis
filiformis), Mock Bishop's Weed (Ptilimnium capillaceum),
Roughfruit Scaleseed (Spermolepis divaricata), and occasionally Wedge-Leaved
Eryngium (Eryngium cuneifolium). Curly parsley is said to be
preferred, but I've always used the Italian Flat Leafed. Caution:
Water Hemlock is extremely poisonous to humans and pets if eaten, and is not recommended
for the garden.
Black Swallowtail larvae are black with a white
saddle in their first instar. Mature larvae are green with black bands, edged with
yellow spots. They reach about 2" long. Just before going into the
chrysalis stage, they will 'clean their guts' and poop a really nasty mess. Then
they'll hunt for a place to pupate. I give them a stick to climb on. They
cling to the stick for a day or so, and a silk girdle is spun around the upper part of the body. Soon,
the cat is hanging from the girdle and his hind feet only, leaning back. It appears
to have 'shrunk' a bit too. Then, the skin splits, he wiggles out and the chrysalis
is there. It's really a neat process to watch. This seems to be the hardest
part of the entire life cycle. It appears to be a great struggle for the caterpillar
to get that skin off. The chrysalis will sometimes move it's 'tail' when
disturbed.
The egg takes about 6
days to hatch. Caterpillars stay in this stage for 10-14 days, and then stay in the
chrysalis stage 8-12 days, or they will overwinter. Some have brown
chrysalis', and some are green.
This is a camouflage
technique used often in the animal world. Green blends best with green bushes, and
brown blends with dead branches. The chrysalis will
become darker, and
then transparent right before emergence. Upon emergence, a
'seam' in the chrysalis opens up (sorta like a flap) and the butterfly just climbs out,
like crawling out of bed.
The new Black
Swallowtails are adult butterflies when they emerge - there is no such thing as a baby
butterfly (unless you are talking about the caterpillars). It takes only a couple of
hours to dry the wings before it is ready to fly. I like to keep mine safe in their
container until they are ready, but, if I know I will not be home for several hours, I
will put them on the Penta (out in the sunshine) and let them dry there. This is a
great time to get some 'up close' photos of my new butterfly. The photo at the left
is not faked. These are 4 Black Swallowtails that emerged one morning. I
brought them all out to my Penta and they all cooperated for the photographer.