I worked with PEI Fish and Wildlife and UPEI in the mid-90's on a study into the ecology of PEI coyotes. We collected, dissected and weighed over 250 animals over two years. The following numbers are based on memory here but i have the report I wrote at home and can dig it up to get exact numbers. The average weight was in the low thirties, but that included juveniles. The average adult weight was about 40lbs for adults. The largest was a shade over 55 lbs.
That said, PEI coyotes were significantly larger (5-10%) than NS and NB coyotes on average. This was believed to be due the abundance of abandoned apple orchards on the Island that allowed coyotes to supplement their diets with fallen apples under the snow. Number one food item was voles followed by snowshoe hare, followed by apples. Nearly every coyote with voles and hare in them also had significant amounts of apples. Those three food items made up about 75% of the diets in the animals we collected.
The average litter size (based on uterine scarring) was about 5 pups.