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BLACK SWALLOWTAIL Papilio polyxenes asterius

The beautiful Black Swallowtail has adapted well to suburban and urban environments.  Sometimes, eggs are even laid onBSwalFreshF.jpg (9272 bytes) 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.  BkSwlCat99F.jpg (14647 bytes)

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.BabyCatsRueF.jpg (21938 bytes)

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 BsPreparingF.jpg (20814 bytes)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. 

BsChryF.jpg (12942 bytes)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. ChryClear2F.jpg (10523 bytes) 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 BSChryBrwn.jpg (56819 bytes)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.

4BSwallowtailsF.jpg (39202 bytes)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.


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