April 12, 2005
Painted Ladies on the move
This year is shaping up to be an irruptive year for PAINTED LADIES (Vanessa cardui). I spent the sunny parts of last weekend counting ladies at selected sites here in Clatsop County. There are a lot of Painted Ladies around, but not nearly as many as are being reported in California where traffic stopping clouds of butterflies are being seen.
See: Seattle Times .
Irruptive movements are a regular occurance among butterflies. I got to see a northbound movement of CALIFORNIA TORTOISESHELLS (Nymphalis californica) back in July of 2002, when 1000's were moving north through the Cascades that also had traffic stopped. It's a pretty amazing sight.
Another famous butterfly migrant is the MONARCH (Danaus plexippus). Monarchs (and Painted Ladies to a lesser extent) are controversial. They take up valuable real estate on their winter ground interferring logging and residential development putting wild populations at odds with developers. At the same time, there is a growing market in live Monarchs, either adults for releases at weddings and parties or as caterpillars for school projects. Some claim that Monarch losses can be mitigated by captive rearing. Some claim that captive rearing muddies the gene pool and makes it difficult to monitor genuinely wild populations. Some claim that release of butterflies bred in captivity has no effect on wild populations one way or the other. Some claim that diminishing winter habitats have put wild populations of Monarchs in jeopardy and unmanaged (and largely avocational) release programs only serve to mask real environmental proplems. Others argue that any crisis has been manufactured by radical environmentalists and a liberal media.
I prefer to err on the side of diversity and habitat protection. If there's a flaw in the endangered species act, it's the lack of an ecological perspective. Habitat loss is the number one cause of species declines, but protection rules don't kick in until it can be proved that the damage has already been done. This seems like an odd way to protect things. Arguements that habitat distruction can be offset by captive breeding programs are cleanly counter-intuitive. Any captive breeding program needs to be tied to a healthy place to go in the wild upon release. Captive breeding should be thought of as a stop-gap measure, not a solution to species declines.
Posted by mbalame at April 12, 2005 5:40 PM