Sentinel species

Sentinel species are animals or plants that scientists use to monitor the health of an ecosystem. Just like when you go to the doctor and they use a thermometer to check if you have a fever, scientists use sentinel species to check the health of an environment.

Let's say scientists are worried about pollution in a river. They might pick a type of fish that is sensitive to pollution and use it as a sentinel species. This fish will act like a "canary in a coal mine" and show signs of illness before other fish or animals in the area.

By monitoring the sentinel species over time, scientists can get an idea of how the pollution is affecting the ecosystem as a whole. If the sentinel fish are getting sicker, it might mean that other fish, plants, and animals in the river are also being affected.

So, sentinel species are important because they can help us understand the health of an environment and help us make decisions about how to protect it. We want to keep our environment healthy for all the animals and plants that live in it, including us humans!