Re: What are the most endangered animals?

This is a difficult question to answer for two reasons.  One, I don't 
actually know what the most endangered animals are, and neither does 
anyone else really.  Two, there are lots of different reasons why a 
species may be endangered, and you can't decide what animal is "most" 
endangered because so many different factors are involved.  We just don't 
understand everything that contributes to extinction.  

You ask if it is true that there are only 7 white rhinos left.  It may be, 
but I don't actually know.  If so, then it is only a matter of time before 
the species is extinct.  Organisms exist as a population, and when the 
numbers become too low, the population is not maintaining itself, and it 
is on the road to extinction.  So declining numbers is certainly a sign of 
a species endangered.  But organisms are hard to count, and these numbers 
are just estimates based upon what we can count.  

Nature is consists of interrelationships between species.  Species eat and 
are eaten, and they interact in many other ways.  To understand why some 
organisms become extinct you might read a nice book that explains WHY BIG 
FIERCE ANIMALS ARE RARE.  Many, but not all, endangered and extinct 
species were not big populations to begin with.  The loss of a species 
means the loss of interactions which may affect other species in ways 
biologists cannot always predict, so this is a very complicated and 
sometimes controversial subject.

Biologists have attempted to inventory endangered species, the Red List 
project (www.redlist.org), and each state in the USA has a list of 
endangered species.  According to various sources here are the number of 
endangered and critically threatened (closest to extinction) species: 
mammals (340 endangered, 180 critical), birds (321 endangered, 182 
critical), reptiles (79 endangered, 56 critical), amphibians (38 
endangered, 25 critical), all animals (1353 endangered, 925 critical), all 
plants (1234 endangered, 992 critical).  Many biologists contend that 
human activities are causing habitat destruction and species extinctions 
at an unprecedented rate.  Links for more information can be found at many 
places on the WWW.  You can start searching for information at the site 
mentioned above (www.redlist.org/info/links.html). But it is hard to find 
a list of the most endangered species even with all of this information.