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Habitat . The Place Where an Organism Lives. Species’ Diversity. The number of species in an area. Diversity Depends on Area. Corporate Farming. Logging . Urbanization. Grazing. Recreation. Mining. Road Building. Are all causes of Habitat Destruction, Degradation and Fragmentation.
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Habitat • The Place Where an Organism Lives
Species’ Diversity • The number of species in an area
Corporate Farming Logging Urbanization Grazing Recreation Mining Road Building
Are all causes of Habitat Destruction, Degradation and Fragmentation
They have all contributed to the decline of our forests, rangelands and aquatic habitats.
The picture to the left illustrates the fragmentation of a segment of land from its original landscape in 1831 to its fragmented landscape in 1950.
This also illustrates the decline in land area or fragmenting of a landscape over time. What forms are islands of habitat where once there was a vast expanse of habitat.
According to recent studies, habitat destruction is the leading cause of species endangerment.Studies show that logging affects approximately 14-17 % of federally listed species, grazing impacts 19-22%, water development 29-33%, recreation 23-26% and mining 14-21%
Fragmenting a Habitat reduces the total amount of area of the original habitat type.
Habitat fragmentation affects the flora and fauna of a given ecosystem by replacing the naturally occurring ecosystem with a human dominated landscape which may be inhospitable to a certain number of the original species.
This human landscape may contribute to the extinction of species within habitat islands by slanting the ecosystem balance in favor of species which are highly adaptable to changing conditions.
The Cowbird… • Populations have increased dramatically since humans began altering the landscape on a large scale in North America • Nest parasites – meaning they replace the eggs of another species with eggs of their own, allowing the other bird species to unknowingly incubate and raise their young.
Forest Dwelling Songbirds.. • Populations have decreased • Declining reproductive success
Secondary Effects • Can reverberate throughout an ecosystem • For example, if a top predator is lost from an area because the fragment is too small the numbers of small omnivores will increase, which in turn may cause excessive predation on songbird eggs and hatchlings and their populations will decrease.
The crisis is large and it is global…What has been done?What can be done?What should be done?What can you do?