From the Fall 2013 Conservationist for Kids
Threats to Biodiversity
By Gina Jack
Loss of habitat, unsustainable taking of animals and plants from the wild, competition with invasive species, disease, pollution and a changing climate all threaten biodiversity. Species may become reduced in number or even extinct. How much an individual species is affected depends upon how numerous and widespread it is. Species that are less common tend to be more vulnerable to change, and their populations are less able to adjust.
If an animal's habitat is reduced in size or quality, it may have problems finding everything it needs to survive. Human activities such as land development, pollution of air and water, use of some pesticides, and placement of roads affect the quality and size of habitat and an animal's ability to get around.
Emerald ash borer
Invasive species are non-native organisms that cause problems in their new environment. Emerald ash borers (beetles native to Asia but accidentally brought into our area) kill ash trees. When ash trees die, animals which depend on them for food and shelter-including native insects, birds and mammals-are harmed. People use ash trees, too. Their wood is preferred for baseball bats.
In the late 1800s, ladies' hats adorned with feathers from snowy egrets were the height of fashion. Birds were killed just for their feathers. Egrets were on the brink of extinction until concerned individuals spoke up. In 1918, one of the first significant national conservation laws for wildlife, The Migratory Bird Treaty Act, was passed. It protects all migratory birds from unregulated harvest. Biologists today work hard to ensure that harvest or collection of wild animals for food and other purposes is done sustainably.