The deer which come to the salt lick, stay all summer.
The deer which come to the salt lick stay all summer.
OR
The deer, which come to the salt lick, stay all summer.
Either two commas or no commas, depending on what you mean.
http://grammar.ccc.commnet.edu/grammar/commas.htm
See #4 here.
To understand why the deer stay at the salt lick all summer, we need to consider their behavior and biology.
Deer are herbivorous animals, meaning they primarily eat plants. However, they also have specific nutritional needs which are essential for their overall health and survival. One of these needs is the consumption of minerals, including sodium, which can be found in salt.
Salt licks, also known as mineral licks, are natural or artificially created areas where animals, including deer, gather to consume mineral-rich salts. These salts contain essential minerals like sodium, calcium, potassium, and phosphorus, which are necessary for various bodily functions.
During the summer months, deer may face challenges in finding adequate sources of these crucial minerals in their natural habitat. As vegetation becomes drier and less nutritious, the deer may begin to develop deficiencies in important minerals. Salt licks provide them with a concentrated source of these minerals, helping them maintain their health and overall well-being.
When deer discover a salt lick that meets their needs, they tend to return to it repeatedly. The habit of visiting the same salt lick can persist throughout the summer months. This behavior is driven by the natural instinct of seeking out necessary nutrients to sustain their bodies.
So, in summary, the deer stay at the salt lick all summer because it provides them with essential minerals that may be lacking in their regular diet during that time.