A decline in the population of a species cannot be judged good or bad without proper context. An article in today's paper ignored this rule in a discussion about the decrease in the number of people in Germany and how it would have negative implications. They compounded this error by extending this impact to the entire Euro zone.
Any living creature imposes stress on its environment. If the stress exceeds a certain level, then the species suffers, often catastrophically. The emptying out of small towns and cities in Germany is not an indication that people are on the verge of extinction in that country, nor is it any indication in a drastic reduction in the quality of life. If ten people try to eat one pie each person will have less pie than if it was shared by eight people. (Beware of arguments by analogy and metaphor).