Skunks vs my hummingbird feeder.

why are you limiting the potential eater of sugar water to skunks?

is your feeder being emptied of nectar?

sounds like bats to me...

Bats eat insects. why would they be interested in sugar water

dessert?

Sounds reasonable enough for me. Then again, shouldn't we give them something like ice cream sundaes covered with roasted bugs for their dessert? Someone should invent an open air freezer unit to keep the ice cream from melting but allow access to the ice cream to the airborne bat.

Could be fruit bats I suppose. called flying foxes here.

Most eat insects, but eight feed only on flowers and fruit, and are known as fruit-bats or flying-foxes. Four of these are amongst the world's largest bats (links to pictures of these are provided below). They may weigh up to one kilogram and their wings may span more than a metre. Because they are large and can fly long distances they can cause considerable damage to cultivated fruit. There are several other kinds which are much smaller animals and are rarely a problem.

Not sure if you have flying foxes in the US
Looks like a no to me
Pteropus:
They are commonly known as the Fruit Bats or Flying Foxes among other numerous colloquial names. They live in the tropics and subtropics of Asia (including the Indian subcontinent), Australia, Indonesia, islands off East Africa (but not the mainland Africa), and a number of remote oceanic islands in both the Indian and Pacific Oceans.

A little research can be very informative
Bats
In some parts of the American Southwest near the Mexican border, bats like hummingbird feeders, too. Dan True got this photo of a Mexican long-tongued bat raiding the pantry. These gentle mammals are voracious nectar lovers, but they are also vital pollinators of saguaros, other giant cacti, and the large agaves.

Bats can empty your feeders overnight, every night. If this is a problem for you, use a feeder with bee guards. Taking feeders in overnight will keep the bats away, but remember that hummers start feeding as early as 45 minutes before sunrise, and they really need the energy after a cool night.

In the eastern US we have many "clear wing" hummingbird moths that will often feed at hummer feeders. They are just a little smaller than hummers and make that same buzzing sound with their wings. Its an example of convergent evolution in multiple species.

I accept your apology...

I kinda thought you might.

skunks are the camp followers of the animal kingdom.

hummingbirds are the first battalion.

It's more likely a raccoon or a bear. Both are good climbers, are active at night and like sweet water. Skunks are very poor climbers. There are no nectar or fruit eating bats in New Hampshire (or anywhere in the NorthEast).

I would bet on Raccoon, but it would help to know more details on what you mean when you say "comes under attack".