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Monarch butterflies
have two amazing and wonder-full processes associated
with their life cycles. First is their phantasmagoric
metamorphosis from egg to caterpillar (larva) to
chrysalis (pupa) to butterfly (adult). This process
can be watched in your own home by collecting a
monarch caterpillar (photo 1)
and keeping it in a large jar supplied with fresh
milkweed leaves and covered with a lightweight top
with air holes. Within several days (depending on
how big the caterpillar is when you find it - almost
always browsing on milkweed leaves) the caterpillar
will attach itself to the underside of the jar lid
and hang its body in the shape of a "j", and then
turn into the most amazing gold speckled jade green
chrysalis(photo 2). Once
the chrysalis is formed, the lid, with the attached
chrysalis, can be taped or tacked to an out-of-the-way
spot (under a mantle, bookshelf, or window frame
are nice options). In about 10 - 14 days the green
chrysalis will turn transparent (photo
3) and the butterfly will emerge (photo
4). Give the newly hatched Monarch a few
hours to pump life into its body and then release
it outside, preferably near or on flowering plants
such as goldenrod, asters or buddleia (photo
5).
The second amazing thing about Monarch butterflies
is their migration. Monarchs that we see in the
late summer east of the Rocky Mountains will migrate
to, and over-winter in, the mountains of central
Mexico. In March as temperature and day length increases,
over-wintering Monarchs will start to migrate north.
These 8 to 9 month old butterflies will mate and
lay eggs, thus establishing the next generation
of butterflies, and then die. As spring proceeds
to summer, successive generations of Monarch butterflies
(living only 3 to 5 weeks) following the growth
of milkweed plants northward are produced. These
butterflies repopulate the United States and southern
Canada with millions of Monarchs. The late-season
generations of Monarch butterflies which emerge
in August and September (perhaps the great-great-grandchildren
of the previous over-wintering adults) do not mate
and lay eggs for a new generation. Instead, they
store fat in their bodies and begin their 1 - 3
thousand mile migration to central Mexico, where
they will over-winter and restart the cycle in the
following spring. Thus the Monarch butterfly (4
to 5 generations removed) flies from Block Island
to the same southwestern faces of central Mexico
mountainsides from which its ancestor originated.
Much of the amazing story of the Monarch butterfly's
migration has been discovered by tagging butterflies.
To participate in tagging Monarch butterflies on
Block Island contact Ocean View Foundation director,
Kim Gaffett at 401-466-2224.
To find out more about Monarch butterflies and associated
research programs -including starting your own tagging
project, go to www.monarchwatch.org.
Also, check out Wings in the Meadow by Jo
Brewer--delightful summer reading for the young
and young at heart. |
Connecting People and Nature