In a pond ecosystem, red-winged blackbirds, mosquitoes, algae, lily pads, cattails, and perch are called
a population
a community
0 0 0 0
abiotic components
a food chain

A community

Explanation: Abiotic is not living, all the things mentioned are alive so this is not correct.

A population is a number of organisms of the same species living together in an area at the same time.

A community is an interacting group of various species in a common location. The common location here is a pond.

A food chain shows the flow of energy and material being transferred from one organism to the next. The example given could be a food chain, but what disqualifies it from being a food chain is the perch it does not provide energy to any of the organisms listed in your example.