Answer: I'm a bit perplexed. It sounds like your cucumbers are suffering poor pollination. This results is fruits that don't grow to normal size, can turn yellow, and soon shrivel and fall off the plant - yet you mention you have an abundance of pollinators. The only other thought I have is that sometimes with the cucurbit family of vegetables, you can have one type of flower (male or female) appear a few days before the other sex type of flower begins to show up. Fruit can only set when both are present. This situation corrects itself in a short time.
There is also a disease called bacterial wilt that can cause these symptoms. Affected plants will wilt, sometimes very quickly, even though the soil is moist. Wilt diseases affect the vascular, or circulation, system of the plant. Keep an eye on the plants for this wilting symptom. Bacterial wilt is transmitted by cucumber beetles, so the way to control it is to control the beetles--perhaps the easiest way is to grow them under a row cover. Unfortunately it's too late for this season. You should pull up and destroy plants infected with bacterial wilt, since there is no treatment.
Q&A Library Searching Tips