Allegheny River Headwaters Watershed Conservation Plan

Allegheny River Headwaters Conservation Plan
Chapter 4. Biological Resources
for 10–11 months. Once mature, the larvae pupate close to the bark surface, and then chew threw the bark
to emerge within approximately three weeks (Haugen & Hoebeke, 2005).
While native woodwasps only attack dead or dying trees, the invasive Sirex woodwasp will also
attack living pine trees. Infected trees show signs of infection; within three to six months following the
infestation, the tree’s foliage initially wilts, then changes from dark green to light green, then to yellow,
and finally red. As the adults emerge, they chew round exit holes 1 / 8 to 3 / 8 of an inch in diameter (Haugen
& Hoebeke, 2005).
European gypsy moth
The European gypsy moth was introduced to the U.S. in 1869 for the production of silk, and it
escaped confinement. The entire Commonwealth of Pennsylvania is infested by European gypsy moths.
Female moths lay their egg mass—cluster of eggs—from which approximately 1,000 hungry caterpillars
hatch and feed upon the leaves of 300 species of trees and shrubs.
Infestations of the European gypsy moth are being reduced and controlled by fungal and viral
pathogens. Entomophaga maimaigo is a fungus that attacks the gypsy moth caterpillars and was first
reported in 1989. Nuclopolyhedrovirus was accidentally introduced in Boston in 1906. The virus infects
gypsy moth caterpillars and is used by the U.S. Forest Service to control European gypsy moth
populations.
Spiny water flea
The spiny water flea is a tiny crustacean with a long, sharp barbed tail spine that was accidentally
introduced in the U.S. in 1984 when it was discovered in Lake Huron. Most likely, its introduction was
from contaminated ballast water from a trans-oceanic freighter.
When in warm water conditions, the female spiny water flea reproduces rapidly, producing 10
offspring every two weeks. During winter months, the produced eggs lie dormant. The water flea
competes with small native species that feed on plankton. They are prey for larger fish species, smaller
fish species cannot feed on them, due to their long tail spine.
Most often, they are accidentally dispersed when they or their eggs, although unseen, end up in bilge
water, bait buckets, and livewells—aerated bait storage containers for live bait. It is even possible that
fishing lines and downriggers could be coated with eggs and adults; and therefore, should be thoroughly
washed, along with any watercraft equipment, after each use, especially after being in different
waterbodies.
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