What other factors may influence pollination rates

Things like an increase in the amount of pollinators (Bees, flys, wasps, mosquitos, certain bats.) Also the time of the year (Because during Spring, flowers increase pollen production.)

Explanation:

During Winter, many of these pollinators go into hibernation, and then wake up during Spring. Which is why during the Spring pollen levels and flower populations drastically increase. Flowers will also increase the amount of pollen they produce at this time, because they have internal thermometers and measure the amount of sunlight. So once days get longer, they know it's Spring and there will be many insects waking up from hibernation. Hope this helped!