Difference between Lurk and Skulk

LURK vs SKULK: NOUN

A group of foxes.
Same as skulker.
A number of foxes together; hence, a number of other animals or of persons together: as, a skulk of thieves.
One who skulks; a skulker
One who, or that which, skulks.
A number of foxes together.

Wait in hiding to attack
Lie in wait, lie in ambush, behave in a sneaky and secretive manner
To remain concealed in order to ambush
To remain unobserved
To hang out or wait around a location, preferably without drawing attention to oneself
To view an internet forum without posting comments
Be about

To lie hidden; to lie in wait.
To keep out of sight.
To read but not contribute to the discussion in a newsgroup, chatroom, or other online forum.
To exist unobserved or unsuspected.
To move furtively; sneak.
To wait out of view.

To hide, or get out of the way, in a sneaking manner; to lie close, or to move in a furtive way; to lurk.
To evade work or obligation; shirk.
To move about stealthily.
To lie in hiding, as out of cowardice or bad conscience; lurk.

To lie in concealment; hide or keep out of sight, as for ambush or escape; skulk.
To be latent or undisclosed; be withdrawn from open manifestation; exist unperceived or unsuspected.
Be about a place without any apparent purpose
To monitor a web forum or similar without making your presence pubilc

To withdraw into a corner or into a close or obscure place for concealment; lie close or hidden from shame, fear of injury or detection, or desire to injure another; shrink or sneak away from danger or work; lurk.
To produce or bring forward clandestinely or improperly.
Move furtively

Mill about, Lie in wait, Mess about, Lallygag, Lounge, Ambuscade, Ambush, Scupper, Bushwhack, Lollygag, Tarry, Waylay, Loiter, Skulk, Linger

Traipse, Slither, Loiter, Amble, Flit, Sidle, Saunter, Cower, Scurry, Wander, Slink, Sneak, Malinger, Prowl, Lurk

Mill around, Mill about, Mess about, Lie in wait, Lallygag, Hang around, Footle, Lounge, Ambush, Scupper, Lollygag, Tarry, Loiter, Skulk, Linger

Cavort, Tiptoe, Roam, Traipse, Slither, Loiter, Amble, Flit, Sidle, Saunter, Cower, Wander, Sneak, Malinger, Lurk

And inflation fears still lurk just below the surface.
Behind each tree or log might lurk a savage.
What may lurk beneath our toes in the surf?
Even worse, dangerous dancing adversaries lurk in the shadows!
Qaeda still lurk near the permeable Afghan border.
Highly accurate ballistic missiles lurk in every theater.
Core Rulebook IIIFearsome and formidable foes lurk within.
But the virus can lurk in dormant mosquitoes.
Remove any bruised areas where bacteria may lurk.
Nary Hungummory Poses the Question, Does Essential Savagery Lurk Beneath the Skin of Civilization, or Does Essential Civilization Lurk Beneath the Skin of Savagery?

Enter the house, and go out the other side, to the base of a concrete building you can skulk around, or head into.
Spine of the World Orcs: powerful orc tribes skulk in stone fortresses stolen from thedwarves and renamed Eyegad, Tame, and Vokan.
Of course, you say yes and skulk back to your desk fully aware it will be anything but quick.
Skulk adventurers, however, are outcasts from their coterie, forced into a life of danger by necessity rather than choice.
Nowhere were we safe from them, and we had to skulk on our own bases.
But when the man actually gets close to them, they tuck their tails and skulk away.
Preble, since her crew is aboard here, and by that means skulk clear of duty.
Put on kerosene using a small brush to the places where they usually skulk.
In many cultures, evil magicians could transform into animal shapes and thus skulk about.
Porch pirates like to skulk in the shadows.