How far can a Gypsy Moth fly?

The short answer is not far enough to land on our shores!

By Myles Rydeen

Those of us who watch the comings and goings of the marine traffic on our door step are used to seeing the deep water vessels approach Victoria to board their pilot and then head off east to one of our west coast ports. Another group of ships sail much closer to shore along the Dallas Road cliffs and, once the pilot has debarked, the vessels then head south across the strait and out towards the open Pacific.

There is yet another group of ships visible that remain at anchor at Constance Bank about five kilometers off shore. While the Strait of Juan de Fuca is about 300 or more feet deep off Victoria, there is a shallower bank where the water is only 90 feet deep. This makes an ideal place for ships to anchor. There are five designated anchorages on Constance Bank with different uses. It is the Pilot Station at the end of the breakwater where it is determined where a vessel is to anchor, depending on the reason for the need to anchor. One anchorage is designated for emergency purposes. Two anchorages are utilized for vessels that arrive only to find that the berth they are headed to is already occupied by another vessel thus need to wait for that vessel to sail. We most often see large automobile carriers anchored on the bank as they await the docks up the Fraser River at New Westminster to be cleared. These ships bring several thousand Asian-built vehicles to the auto terminals on the Fraser. It is also not uncommon to see huge container ships at anchor on Constance Bank as they wait their turn at the Delta Port terminals opposite the Tsawwassen ferry terminal.

The other two anchorages are designated for Asian Gypsy Moth inspections carried out by Agriculture Canada. This moth is common to some areas of the western shores of the Pacific Rim countries. Agriculture Canada and its American counterparts know that the moth would survive in our climate and that it could be devastating to many different plants in our area. Both forested areas and agriculture crops would be at risk. Marine traffic is monitored by these agencies, and any vessel scheduled to arrive in our waters that originated in affected areas must be inspected. The teams that are sent out know where to look for egg masses and moths - typically high up off a deck and in dark recesses. Once cleared, the ship may proceed. If moths are found, the ship is sent back out to sea to have a spraying program undertaken before returning for another examination.

Those with eagle eyes can tell which ships are being inspected for Asian Gypsy Moths by looking for the small tug drifting off the stern of the cargo ship. The Seaspan Foam, which is a familiar site for breakwater walkers, transports the inspectors out to the ship and then remains tethered to the ship until the inspection is finished.

There is no need to worry. The Gypsy moth can fly only about one kilometer and could never reach our shores!