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Hi, I'm Jensen Morgan. We're going to talk about some great concepts in environmental science. Today's topic is overexploitation. So let's get started.
We're going to talk about overexploitation, the various types of overexploitation, its impacts, conservation biology, and tools to address overexploitation. Overexploitation also happens to be our key term for today. It is the use of a natural resource by humans to a point that is unsustainable. Overharvesting is another word that can be used in place of overexploitation. Factors which contribute to overexploitation include increases in human population growth, human over consumption of natural resources, and a lack in the practice of conservation and management of natural resources.
There are many different types of overexploitation, and we're going to cover a few. The fur trade is a prime example of overexploitation. In the past, when one animal would become rare for use, another animal source would then be used. For example, in the beginning of the 1900s, squirrels and minks were becoming rarer and harder to find for use in clothing. In response, the sea otter was heavily hunted and harvested as a replacement, but nearly became extinct in the process.
Then there's the fishing industry. Current commercial fishing practices and harvest is exceeding fish populations' recharge and reproduction rates. The majority of the big predatory fish at the top of the food chain have been overharvested so much that they can no longer be fished. Now, fish lower down on the food chain are being harvested. For example, in the Great Lakes, sturgeon populations have declined from overfishing.
Amphibians and reptiles are overharvested for food, skins, souvenirs, and medicines. Many amphibians and reptiles have long lifespans, slow growth, and low reproductive rates, which makes it even harder for them to recover from overexploitation. The pet trade is another example that could be considered overexploitation, as well as the overuse of forests and overgrazing with pastor animals.
Overexploitation of one species can have repercussions on the rest of an ecosystem. For example, the decline in one species population which is food for another would result in the second species' decline as well. Or, when two competing species balance each other in ecosystem and then one is overexploited, the second species' population could skyrocket and cause further effects in the ecosystem.
If you remember, conservation biology is the study of impacts to biodiversity with the intention of conserving biodiversity. The physical structure of a landscape can play a large role in biodiversity health. Habitat fragmentation, or land that is developed for human use, which causes habitats to shrink in size and creates more boundaries and edges between ecosystems. Important to remember, as edge area increases, biodiversity tends to decrease.
Conservation biologists tend to attempt to mitigate this problem by creating corridors of land between habitat areas that allow ecology to be more mobile and can stabilize biodiversity. Conservation biologists study the dynamics of ecology to aid in establishing protected areas to slow the loss of biodiversity. Challenges to conserving species are that it often requires resolving conflicts between the habitat needs of species and human desires. Sustainability seeks to provide for human needs while conserving biodiversity.
Tools to address and mitigate the impacts of overexploitation include national laws, which regulate the trade in endangered species; international agreements to restrict overexploitation of species; restrictions on hunting based off of annual quotas; positive and negative economic incentives to discourage overexploitation. Positive would be compensation in the forms of cash, goods, or services to encourage particular conservation practices, while negative would be things like fines and penalties for poaching. Important to note is that even the best scientific knowledge and practices to manage exploitation can be challenging to implement and often fail due to institutional difficulties.
Now, let's have a recap. We talked about overexploitation, the various types of over exploitation, its impacts, conservation biology, and tools to address overexploitation. Don't forget that our key term was, in fact, overexploitation, which is the use of a natural resource by humans to a point that is unsustainable. Well, that's all for this tutorial. I look forward to next time. Bye.