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Observations: August 24, 1999 |
What do Cabbage Butterflies eat in the park?  Cabbage Butterfly (Pieris rapae), a small, white butterfly with black wingtips (3.5 - 5 cm) is one of our most commonly spotted species at Irving Nature Park despite the fact there are no cabbages, nor any other garden vegetables, nearby. While in its bright green caterpillar stage this insect's favourite food is cabbage, as well as kale and broccoli, veggies related to the mustard family (Brassicaceae). Adult butterflies are frequently seen on Black Mustard, a common park species with yellow, four-petaled flowers, found in the old fields and roadsides of the park.The Cabbage Butterfly arrived from Europe in the 1860's via shipping cargo. An impregnated female butterfly dissuades additional suitors through a distinctive flight pattern. The female, after being circled by a male near the ground, will fly upwards in a spiral motion around the male, sometimes to a height of 20 metres. The male butterfly quickly gives up the chase and drops to the ground like a stone, while the female descends slowly, hoping the male will move on to another female. Look for this spiral flight pattern over the park fields during the summer.
 Along the trails of the park you may notice a strange looking plant that is totally white in colour and stands up to 15 cm in height. We know it here as Indian Pipe (Monotropa uniflora). Most visitors think this plant is some sort of fungus that feeds off the nutrients found within decaying plant material in the area. This is only partially true. Indian Pipe is a plant, not a fungus, but it does not contain chlorophyll, a chemical that green plants use to convert soil nutrients, water and sunshine into food. Instead this plant forms a partnership with a fungus living amongst its roots. The thread-like fungi attach to the roots of neighbouring trees and become a conduit through which carbohydrate is slowly passed from the trees to the Indian Pipe roots. This association benefits all of its partners. While the trees supply food to both the fungi and Indian Pipe, the trees gain access to a more extensive reservoir of water and mineral nutrients. Indian Pipe probably produces substances which stimulate the growth of fungi in the vicinity of its roots. | ||
The park has a foreign invader! | ||
Have
you spotted this foreign invader during the late summer months?
It comes from the mountains of Asia! Himalayan Balsam (Impatiens
gladulifera) has a fragrant, pinkish flower that resembles a witch's
hat. Usually found in the wet, shady area at the beginning of
the Sheldon Point trail,these flowers transform into long slender
seed pods that burst open when touched. (Its common family name
is "Touch-Me Not".) Likely this asiatic species came to the Bay
of Fundy in ballast waste from shipping. Because of its exotic
foreign origin there are few local predators for this plant. The
plant spreads its seeds unchecked, crowding out species of native
plants. Another invasive foreign plant species is purple loosestrife
(Lythrumsalicaria). It is threatening wetland habitats throughout
North America. In the Maritimes a species of beetle which feeds
on loosestrife has been introduced to control the spread of this
plant. Biologists are considering importing insects to control
other invasive species like Himalayan Balsam.
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The Naturalist's Notebook is a regular publication. If you have any questions or topics that you would like to see addressed, please call John Gilbert, Manager, Fish and Wildlife, J.D. Irving, Limited, (506) 632-7777 or email honeyman.kelly@jdirving.com |