The people of Assateague and the surrounding areas joke that the mosquito is their state bird, but make no mistake...I grew up on an island and have never seen anything like this. Do not even dream of going without insect repellent on your skin, clothes, gear, pets, sleeping bag or any other surface. We were there during a notoriously bad mosquito summer, but I counted about 157 bites on my way home and that was with 97% deet directly on my skin on 30 minute intervals. The ocean side of the island (vs. the bay side) is touted to bet better, but it was nearly unbearable. We camp quite a bit and do not mind bugs much but many people that we encountered looking for a nice family vacation did not leave their tents except to go to the beach and even then I recommend sunblock with insect repellent in it to combat the biting black flies. After dark, wear long sleeves and long pants and make a fire on the beach and you should be ok, otherwise, stay in your tent and read a book. We had a friend's dog with us and did not want to put repellent on her fur in case she licked it, so we put some on a bandana around her neck...she was bitten so badly that her face swelled, we called her vet's emergency number and had to give her benadryl every night so that she could sleep...the mosquitoes were not messing around!
You can see the bugs moving in the shallows as you walk along the nature trail. If your with someone and your bihind then, you will see at least 15+ mosquitoes swarming them if you don't have bug spray on. I have never seen anything like it, these mosquitoes have wingspans of 1/2 inch or more! COVER UP!