Changes in Allele Frequency in real life

Changes in Allele Frequency in real life
The Hardy Weinberg equation states that allele frequencies in a population remain constant
provided that:
 the population is very (ideally infinitely) large
 there is no migration/immigration
 there are no mutations
 fertilisation and mating are random
 there is no differential survival/reproductive success
Such a population would be non-evolving.
Does it ever apply in real life?
Look at the following examples. How many of the Hardy Weinberg criteria do they fulfil?
What implications does this have for the evolution of these species?
Giant Clams
Giant clams, as adults, are sessile organisms. They reproduce by
squirting millions of gametes, eggs and sperm, into the ocean.
Elephant seals
Males defend and maintain harems with a median number of 16
females, to whom they have exclusive mating rights. They were hunted
to the edge of extinction by the end of the 19th Century.
I don’t think I need to tell you anything about bacteria.