The answer is static friction
Well, considering if the deer and the hawk have a direct predator prey relationship, where the deer are the prey, then the hawk population will also drop quite a lot, unless they have some other major food sources, but chances are they'll still drop.
If it's NOT a direct predator prey situation, for example: The deer happen to eat something that the hawks also eat, or the deer are prey for something the hawks eat:
If the deer eat something the hawks eat, by them dropping it means there will be more food supply for the hawks, meaning as the deer population drops, the hawk population will go up.
If the deer are PREY to something the hawk eats, then by there being less deer, then whatever the primary consumer of the deer is will also drop. If the hawk eats that predator, then there will be less of those predators, and less prey, meaning the hawk population will still drop
You were most likely given a food web to look at. Seeing how you didn't post that, I just gave you the only 3 situations that could happen.
~Hope this helps!
<span>Pacinian corpuscles are rapidly adapting mechanoreceptors so they respond only at the onset and offset of the stimulus. The Pacinian corpuscle has a single afferent nerve fiber. Its end is covered by a sensitive receptor membrane whose sodium channels will open when the membrane is deformed in any way. Pressure thus causes sodium to enter the neuron and create a generator potential. If this potential reaches a certain threshold nerve impulses are formed. This impulse is now transferred along the axon with the use of sodium channels and sodium/potassium pumps in the axon membrane. The magnitude of the stimulus is encoded in the frequency of impulses generated in the neuron. So the more massive or rapid the deformation of a single corpuscle, the higher the frequency of nerve impulses generated in its neuron.</span>
