Carrying Capacity
The carrying capacity is the maximum number of species that can be supported in a bioregion. A pond may be able to support only a dozen frogs depending on the food resources for the frogs in the pond. If there were twenty five frogs in our classroom's pond, half of them would probably die because the pond environment wouldn't have enough food for them to live.
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This is an example of different species of fish inhabiting the same area.