Question

How will the increase in the tuna population affect the other populations? Be sure to explain whether the dolphin population, the squid population, and the herring population will change, and why.

Answer 1

The increase in the tuna population can have both positive and negative effects on other populations in the marine ecosystem, such as dolphins, squid, and herring.

Step-by-step explanation:

The increase in the tuna population can have effects on other populations in the marine ecosystem.

1. Dolphin population: An increase in the tuna population can lead to an increase in the dolphin population. Dolphins are known to prey on tuna, so a larger tuna population can provide a greater food source for dolphins.

2. Squid population: An increase in the tuna population can have a negative impact on the squid population. Tuna are predators of squid, so a larger tuna population can result in increased predation pressure on squid.

3. Herring population: The effect of the tuna population on the herring population can be variable. Tuna and herring can compete for similar food sources, so an increase in the tuna population might lead to a decrease in the herring population due to increased competition.

Answer 2

Complete question:

Scientists have been studying four populations in one area of the Atlantic Ocean. In this area, both tuna and dolphins eat squid, and squid eat herring (a type of fish).

The data shows that recently the tuna population increased. How will the increase in the tuna population affect the other populations? Be sure to explain whether the dolphin population, the squid population, and the herring population will change, and why.

You will find the image in the attached files.

Answer:

• Tunas´ population increases
• Squids´ population decreases because more tuna eat them
• Dolphins´ population decreases because there are fewer squids available
• Herrings´ population increases because they do not suffer predation by squids.

Explanation:

In the trophic web occurs a process of energy transference through different organisms placed at different levels. Each level feeds on the preceding one and becomes food for the next one. The first link is an autotroph organism or producer. The following links are the consumers: herbivores are primary consumers and feed on producers. Carnivores are secondary consumers and feed on herbivores, and so on. The last links are the decomposers, microorganisms that act on dead animals degrading organic matter.

If any of the links change their population size (increasing it or decreasing it), it affects the superior links and the immediately anterior link.

In the exposed example of the trophic web, tuna feeds on squids. If the tuna population increases in size, there will be more individuals feeding on squids. Squids will be affected because too many animals are eating them, and they will not have enough time to reproduce and recover the normal population size. The mortality rate by predation is higher than the natality rate, meaning that the squid population will decrease.

Dolphins also feed on squids. But as the tuna population increases in size, competition for squid prey will be higher. Both species (tuna and dolphins) will compete for food. But tuna will eat more squids, and hence, dolphins will be affected and decrease in population size.

Usually, herrings are eaten by squids. But as the squids' population decreases, herrings will not suffer from predation, and their population will increase in size.

So, to sum up:

• Tunas´ population increases
• Squids´ population decreases because more tuna eat them
• Dolphins´ population decreases because there are fewer squids available
• Herrings´ population increases because they do not suffer predation by squids.