I'll start right at the beginning. The biology of the lobsters is that they're cold-blooded organisms—poikilotherms—and that they feed and grow based on the temperature they're living in. If the water is warmer, they move around more, they eat more, and so forth.
The fishery in southwest Nova Scotia is really run in the winter, when the lobster slow down because it's colder. The temperatures are between 5° and 10° centigrade instead of 15° to 20°. When you open up out of season in St. Marys Bay, you're dealing with much warmer temperatures, and so you're going to get a much higher catch rate because of it.