Sep. 28, 2017

Human activity causing rapid environmental changes

I recently read an article about the bristle cone pine and how the rapid changes due to climate change are affecting this species. Bristle cone pines are among the oldest living organisms on our planet, some individuals are 5,000 years old. A three year study found that the lumber pine, which is usually found at lower elevations where the temperature is warmer, is encroaching on their ancient cousin trees threatening to crowd out the bristle cones at lower elevations. Because the bristle cones grow so slowly, they are not adapting as quickly as the lumber pines.

The rate of change is happening more rapidly than many species can adapt and is disrupting ecosystem relationships. Botanists have found that many of our food crops are flowering early before their migrating pollinators arrive. Soil scientists have concerns about the loss of healthy bacteria and fungi which are part of the nitrogen cycle and a natural fertilizer of soil for plant growth. Insects, such as the beetle infestation in four corners area, thrive in warmer climates and are decimating forests, which serve as habitat to many species. Diseases involving mosquitoes (West Nile Virus, Zika), ticks (Lyme’s) and fleas as vectors are increasing their ranges due to higher temperatures at mid-latitudes.

Wildlife biologists have seen mountain organisms moving to higher elevations to stay in their temperature ranges and changing migration patterns of herd species and birds. Birds arrive on schedule to find their food sources--insects, seeds, flowering plants--have hatched or bloomed too early or not at all. Milder winters cause seasonal food caches to spoil, so wildlife species like the Gray Jay depending on food stores to survive the winter are left without sustenance. They have seen an increase in the ratio of male to female reptiles because temperature of incubation affects the sex of some reptiles including turtles and crocodiles.

Oceanographers are observing coral reefs failing across the tropics, which affects biodiversity and the protein source for nearly a quarter of the world’s population. Warmer ocean temperatures contain less oxygen, reducing fish size and lower pH affects the chemical process of shell fish.  

Climate change is altering key habitat elements that are critical to wildlife's survival and putting natural resources in jeopardy. Organisms require a certain temperature range, fresh water, food sources, shelter and nursery areas for developing offspring. Droughts, fires, floods (causing erosion) kill plants on which wildlife depend for food and shelter. Because of the web of relationships, it is difficult to assess how flora and fauna changes affect the whole ecosystem. There is a huge body of evidence regarding climate change and rapid changes in the flora and fauna of many ecosystems.