It's
been established by ancient authors that nymphs are bound intrinsically to whatever
place in nature they arose from, and that instinctively they crave that spot
and return to it often. There are many types of nymphs in Greek myth, but
most seem to fall into two categories -- water-based and earth-based.
Water nymphs range from enormous bodies of water to the smallest. There are Oceanides
(oceans), Nereides (seas), Naiades (rivers), Limnatides
(lakes or harbors), Potameides (streams),
Krenaides (fountains), and
Pegaeae (springs).
Water
nymphs I imagine as being very nearly immortal. The oceans and seas never
really change but springs, fountains, rivers and lakes would be more susceptible
to such things as diversion or drying up, so those nymphs might be mortal.
Generally speaking, there wouldn't be a great deal of seasonal changes in
behavior, as there isn't a great deal of freezing in Greece.
For earth nymphs, there are at least two sub-types -- tree and land. Some types
are given multiple names, as well. Tree-based nymphs are the Dryades / Hamadryades
(tall trees), and Meliades / Epimelides / Hamamelides (fruit trees).
Land-based nymphs are the Oreades (mountains)
and Orestiades / Leimoniades (meadows). There are also supposedly cave nymphs,
though I cannot find names for them.
As for their life spans, tree nymphs were quite definitely mortal. Homer's
"Hymn to Aphrodite" refers to tree nymphs having no real soul
but dying along with their tree. I also imagine tree nymphs to be very
seasonally-inclined, as growing things are greatly affected by seasons. They
would bloom, reproduce, ripen and mature with the seasons, and then fade and
sleep when their tree goes into hibernation. Mountain and grove nymphs are probably
less inclined to mortality, but still affected
by seasonal changes. I am still looking for direct quotations about cave
nymphs.
There
is yet one more set of nymphs I have read of, but these are a far different
from the norm and seem to have been given a single special purpose.
The Meliae sprang from Gaia and the drops of blood Ouranos shed
when Kronos castrated him, and these nymphs were sometimes reported to be the
caretakers of Zeus as an infant-in-hiding. I can easily see them as being similar
to their mythical sisters the Furies, perhaps more like demons than nymphs.
Some
writers misinterpret their name as coming from "melia" ("ash
tree"), making them similar to dryades. But the word is properly taken from
"meli" ("honey") and is explained thusly: In
the beginning of the age of gods, there was no nectar or ambrosia, only honey.
The blood of gods was called ichor and is described very vividly as
being "clear or golden, honeylike in its form". Therefore, nymphs
born of the blood of a god should certainly be called "honey-blood nymphs"
and not "ash-tree nymphs".
As
a further note of interest, the word "nymphe" (νυμφη)
actually means "young wife or bride". Priestesses were sometimes called
"theai nymphai" ("brides of the gods") when involved in
certain rituals, probably sexual. Also, a person in a state of rapture, such as
an oracle, was said to be "nympholeptoi" ("caught by the nymphs").
Some nymphs actually had their own temples, so they were certainly considered
divine beings, even if not goddesses outright.
The word "nymphomania"
was coined by modern psychology to explain a sexual disorder, but I personally find it
somewhat derogatory. Although nymphs of myth were free-spirited (especially
those that followed Dionysos), I don't think they should be considered "girls
of loose morals" or as having "excessive sexual activity based on
feelings of personal inadequacy" as the dictionary defines the word. There are even those depicted in myth
as having run from those who were intent upon ravishing them, and some even
died afterward, Eurydike and Daphne being good examples. I imagine them as being
merely completely in tune with nature itself since they are, after all, born
directly from it.