A whole bunch of the caterpillars in the lab have shut down for the winter. We have been expecting this, as both the Gorgone and Baltimore Checkerspots overwinter as caterpillars of about this stage. They have been caged with fresh leaves, and have stopped eating them over the last couple of weeks. Instead, the caterpillars just sit in small groups on the tops of the cages not moving much. Time to put them into their winter quarters.
The larvae are placed with crumpled paper towels in small plastic food cups. Over time, they will work their way into the folds of the paper towels. Some caterpillars will even silk the folds of the towels together. The cups go on a terra cotta sauceer, and a terra cotta pot is inverted ovet the top.
The drain holes in the pots are plugged with gauze to keep marauding insects out. The whole affair is stored in a shaded area up on the roof of the Nature Museum. Last year, about 70% of the gorgone checkerspot larvae that we placed in these cages survived the winter, and all survivors went on to become adult butterflies. On Friday we placed 512 Gorgone Checkerspot caterpillars and 1256 Baltimore Checkerspot caterpillars into these cages. The field season isn't over- but it is winding down.