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Measuring Populations. By: Andn Sayp. Direct Observation. Counting all the same species one by one. Example: I went to school and all the students lined up at the door and the teachers counted every student that came in one by one. Indirect Observations.
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Measuring Populations By: Andn Sayp
Direct Observation • Counting all the same species one by one. Example: I went to school and all the students lined up at the door and the teachers counted every student that came in one by one.
Indirect Observations • You can count the number of homes of the same species and estimate the number of family members. Example: I went to the prairie and counted all the holes where prairie dogs live in and multiply it by how many live in each hole.
Sampling • Counting the amount of species in a small area and multiply it by how many areas in the spots the species populate. Example: I went to the desert and counted one cactus in one hundred square feet. There is about one thousand square feet in the whole desert so there would be one hundred cactuses in the whole desert.
Mark-and-Recapture Skills • Counting animals by capturing them, marking them, then releasing them back into their habitat and counting how many you have marked. Example: We went to the beach and captured some crabs and marked them, then released them. Then came back in a week and marked the ones we haven’t marked yet and counted them.