Habitat Loss and the Environment

Habitat is defined as the natural home of a plant or animal.

Habitat loss is due to many factors such as: forest fragmentation and deforestation, conversion of land to agriculture, drainage of wetlands for other uses, urban sprawl, contamination of the ecosystem, acid rain, higher levels of UV radiation and the introduction of invasive species. All these have put many plants and animals in danger. Loss alters and potentially eliminates conditions needed for plants and animals to survive. Forest fragmentation leaves isolated patches of ecosystems and disrupts pollination, seed disperal and wildlife breeding and migration patterns. Fragmentation isolates populations and the increased edge habitat results in an increase in predation and brood parasitism. As many predators are more abundant near the edge, reduction in breeding success is seen in fragmented areas. The fragmentation of woodlands also favours brood parasites like the Brown-headed Cowbird. In addition, changes in abiotic conditions, like temperature and the amount of wind near forest edges also affect the health of birds in the habitat. These changes may affect availability of food and nest site suitability for interior forest birds and can extend hundreds of meters into a fragmented habitat.

We can combat habitat loss by doing wildlife inventories, making critical habitat models, bringing in more legislation, doing surveys, improving stewardship activities, making recovery action plans, making improvements to and restorating the habitats, and also by public outreach, land securement and partnering with the First Nations.

Human effects have almost exclusively contributed to habitat loss. Things such as large-scale logging and clear cutting reduces forest cover and interior habitat. Land use practices and conversion of lands to agriculture removes native species and alters wetland filtration. Urbanization destroys habitat as does industrial accidents and pollution.

Habitat loss makes for a less diverse ecosystem. Of note, Ontario is home to 6% of the WORLD'S wetlands and 24% of Canada's. BUT, in Southern Ontario alone, 70% of our wetlands have been lost.

Predators of the eggs and nestlings of bird species like skunks, raccoons, crows and jays, have increased due to less persecution, by human settlement providing more food sources, and the fact that larger predators (like wolves) are now gone. These factors are also contributing greatly to the threat against local bird populations. Add invasive species (like the starling) into the mix and it just gets worse - we need to really take a long, hard look at what we can do to change this.

Dealing with human pollution is another fact of life that animals must learn to deal with. Contaminents move up the food chain in a process termed 'Bioaccumulation'. These chemicals are not excreted and build up over time. This effects bird's egg shells by thinning them, as well as bringing death to the adults at times. This is not restricted to birds species by any means.