: Invasive Species

42 views

I read that invasive species destroy ecosystem that they are in other than their original place but how do they not destroy the ecosystem where they are from?

In: 1

Because the ecosystem they come from has evolved with and adapted to them. It means that they have predators or other systems to keep their population in check, and likewise what they prey on has evolved to sustain itself despite their prey.

When they enter a new environment they do not face the dame resistance and so proliferate enormously and can wipe out unprepared fauna.

If a species is invasive it’s because it’s in the wrong ecosystem. It wouldn’t destroy its original ecosystem because what’s destroying the invaded ecosystem helped the species thrive in its original ecosystem

Most species have natural predators or species around them have developed some kind of defense system. The problem of the invasive species is that their natural predators are not simultaneously introduced into the new environment meaning they can grow unchecked.

In the native ecosystem there’s predators and other factors that keep the species in check but when it’s put in an ecosystem where there’s no predators or anything else to keep them controlled they thrive and eat everything they can.

Im going to assume that they wouldn’t be considered ‘invasive’ in their own ecosystem?

In their “home” ecosystem there are predators which have evolved to eat them, in the case of animals like cane toads, these cane toads are toxic and deadly to most of the animals in Australia which possibly could eat them.

There are two factors:

First, their initial ecosystem adapted to them. E.g. birds in regions with lots of ground-based predators (such as cats or martens) will build nests in inaccessible, sheltered places. Birds on islands without predators dont because, in the past, they didnt have to. Once an invasive predator arriges on their island, they have no defence.

Second, most ecosystems that existed a couple hundred years ago are now gone or altered completely due to humans. That often means that the animals originally living here are now ill-equipped for them. Other ‘invasive’ species, which lived in ecosystems more similar to the human-created ones, are now better equipped for them and displace the original inhabitants.

If bears and wolves are present in the same area. Enough wolves can overwhelm a bear, but a bear can maul a small enough pack of wolves, or alternatively wound and/or kill enough wolves the pack becomes unable to sustain itself, while the bear gets a good meal. In either circumstance conflict between the two may barely be worth it. Wolves kill something, bear shows up to steal, and gets chased off by wolves. Bear kills something, wolves show up to steal, the bear wants it’s kill, but will accept a dead wolf, as food in exchange for the pack getting it’s kill, so the wolves are unlikely to directly challenge the bear unless the know they can win.

As a result, there is an uneasy not-quite-a-truce between them. Conflict usually only happens when there is something to be gained.

Then, because reasons, mountain lions show up in the area. A mountain lion isn’t strong enough to solo-kill, either, a pack of wolves, or a bear. The mountain lion loses either way. But the lion is clever, and will wait for the wolves and bear to fight, and then, kill and eat the wounded, and thus weakened winner of the conflict. (Or steal the food of the wounded, knowing they can’t fight back in thier wounded state or risk death and becoming food)

As a result the mountain lion is the invasive species. In other places, the lion either has it’s own predators, or is limited by some other factor.

Additionally, the example isn’t perfect, as what would likely happen, is that the bears and wolves, would go well out of thier way to avoid each other, so as to not fall victim to the mountain lion. As a result, the mountain lion would likely take to hunting the prey normaly belonging to the wolves/bears. As a result, there is less food for both native predators, caising thier numbers to dwindle, **AND** they now have to compete directly over the exact same food source. This leads to more direct conflict between the two, which niether can afford to avoid, unless they choose to starve.

As a result, the mountain lion is now feasting upon, both, the bears’/wolves’ prey, and the bear/wolf/wolves who won/lost the fight. While the bears and wolves are each having thier food source stolen by 2 predators, and have to fight those other 2 predators, for what food remains, while simultaneously, not falling victim to the second predator (the first was fought off), that swoops in to either, make prey of **them** (in thier wounded state) or **steal** thier food, with the predator knowing, they can’t fight back in thier wounded state, and must let thier food be stolen, or die and become food.

0 views

I read that invasive species destroy ecosystem that they are in other than their original place but how do they not destroy the ecosystem where they are from?

In: 1

Because the ecosystem they come from has evolved with and adapted to them. It means that they have predators or other systems to keep their population in check, and likewise what they prey on has evolved to sustain itself despite their prey.

When they enter a new environment they do not face the dame resistance and so proliferate enormously and can wipe out unprepared fauna.

If a species is invasive it’s because it’s in the wrong ecosystem. It wouldn’t destroy its original ecosystem because what’s destroying the invaded ecosystem helped the species thrive in its original ecosystem

Most species have natural predators or species around them have developed some kind of defense system. The problem of the invasive species is that their natural predators are not simultaneously introduced into the new environment meaning they can grow unchecked.

In the native ecosystem there’s predators and other factors that keep the species in check but when it’s put in an ecosystem where there’s no predators or anything else to keep them controlled they thrive and eat everything they can.

Im going to assume that they wouldn’t be considered ‘invasive’ in their own ecosystem?

In their “home” ecosystem there are predators which have evolved to eat them, in the case of animals like cane toads, these cane toads are toxic and deadly to most of the animals in Australia which possibly could eat them.

There are two factors:

First, their initial ecosystem adapted to them. E.g. birds in regions with lots of ground-based predators (such as cats or martens) will build nests in inaccessible, sheltered places. Birds on islands without predators dont because, in the past, they didnt have to. Once an invasive predator arriges on their island, they have no defence.

Second, most ecosystems that existed a couple hundred years ago are now gone or altered completely due to humans. That often means that the animals originally living here are now ill-equipped for them. Other ‘invasive’ species, which lived in ecosystems more similar to the human-created ones, are now better equipped for them and displace the original inhabitants.

If bears and wolves are present in the same area. Enough wolves can overwhelm a bear, but a bear can maul a small enough pack of wolves, or alternatively wound and/or kill enough wolves the pack becomes unable to sustain itself, while the bear gets a good meal. In either circumstance conflict between the two may barely be worth it. Wolves kill something, bear shows up to steal, and gets chased off by wolves. Bear kills something, wolves show up to steal, the bear wants it’s kill, but will accept a dead wolf, as food in exchange for the pack getting it’s kill, so the wolves are unlikely to directly challenge the bear unless the know they can win.

As a result, there is an uneasy not-quite-a-truce between them. Conflict usually only happens when there is something to be gained.

Then, because reasons, mountain lions show up in the area. A mountain lion isn’t strong enough to solo-kill, either, a pack of wolves, or a bear. The mountain lion loses either way. But the lion is clever, and will wait for the wolves and bear to fight, and then, kill and eat the wounded, and thus weakened winner of the conflict. (Or steal the food of the wounded, knowing they can’t fight back in thier wounded state or risk death and becoming food)

As a result the mountain lion is the invasive species. In other places, the lion either has it’s own predators, or is limited by some other factor.

Additionally, the example isn’t perfect, as what would likely happen, is that the bears and wolves, would go well out of thier way to avoid each other, so as to not fall victim to the mountain lion. As a result, the mountain lion would likely take to hunting the prey normaly belonging to the wolves/bears. As a result, there is less food for both native predators, caising thier numbers to dwindle, **AND** they now have to compete directly over the exact same food source. This leads to more direct conflict between the two, which niether can afford to avoid, unless they choose to starve.

As a result, the mountain lion is now feasting upon, both, the bears’/wolves’ prey, and the bear/wolf/wolves who won/lost the fight. While the bears and wolves are each having thier food source stolen by 2 predators, and have to fight those other 2 predators, for what food remains, while simultaneously, not falling victim to the second predator (the first was fought off), that swoops in to either, make prey of **them** (in thier wounded state) or **steal** thier food, with the predator knowing, they can’t fight back in thier wounded state, and must let thier food be stolen, or die and become food.