Nature has a way of not tolerating emptiness, and all organisms are connected to each other, in closer or further ways. The absence of one, begins to affect all the rest, often resulting in irreversible changes to the environment. The critical situation is to lead to the extinction of organisms and the consequent disappearance of entire ecosystems. The explanation for this process is the cascade effect. You can find out what it is and why it should be prevented in the following article.
What is the cascade effect?
The definition of the cascading effect is encapsulated in the phenomenon of secondary extinction. It occurs when one key species in an ecosystem goes extinct, affecting subsequent species. The stages of the cascade effect are the disappearance of the prey species, the lack of control of the invasive species, the reduction in abundance and finally their extinction.
In ecology, the cascade effect is referred to when predatory species that regulate the number of remaining organisms, called keystone species, begin to disappear in an ecosystem. It results in the ecological release of prey of prey species. Overexploitation of their own resources by themselves may occur, leading to food loss, starvation and eventually extinction. This, in turn, will bring further dependent species to this state, affecting them in a cascade.
Example of cascade effect
A good example of the cascade effect in biology is when wolves start to become scarce in an area. They live in a natural ecosystem together with deer and roe deer, which are their food. If wolves start to become scarce, the number of deer and roe deer is no longer controlled, they have no natural enemies and therefore their population increases. This translates into the amount of food they consume, mainly vegetation. This is also food for other species, for which there may be a shortage in such a situation. In addition, due to the increase in the population of deer and roe deer on the same area, it may lead to them dying out for lack of food themselves.
The cascade effect is well represented by the massive poaching of sea otters on the west coast of the USA, in the 20th century. Through the disappearance of up to a million individuals, the number of sea urchins in the water began to increase significantly. This had the effect of decreasing the diversity of molluscs and the disappearance of seaweeds, resulting in the extinction of many species of fish and invertebrates, which lost their food.
Predicting and responding to effects in a cascade model
The aim of preventing the cascade effect and associated secondary extinction is to prevent the sudden disappearance of one organism in the ecosystem. The absence of one species will affect the functioning of other organisms with which it is closely associated, and these in turn will affect the others. Nowadays, the main factor influencing secondary extinction is excessive human interference with the environment. The taking of more forest land for cultivation or the destruction of the seabed are just examples of negative environmental exploration, the effects of which are usually visible after time.
The danger of cascading effects and secondary extinctions stems from the scale on which the phenomenon occurs and the fact that the losses incurred can only be seen after time. Responsible management of natural resources, combined with environmental analysis based on collected data on ecosystems and their functioning, avoids destruction. Ultimately, the extent to which the effect spreads depends on human responsibility for the planet.
