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Tracking Biomass


Examine the food web below for a freshwater shoreline habitat with an area of 2.5 square kilometers.

Assume that the 121 kilogram/square kilometer of biomass of the vegetation is uniformly distributed throughout the area of the habitat and between the primary consumers in the food web.

A mid-summer drought reduces the total shoreline of the pond by 50%. All the mute swans and geese migrate to a different pond with a larger shoreline.

Which of the following BEST describes the results of these changes after one growth season?

"Chesapeake Waterbird Food Web." Wikimedia Commons, n.d. Web. https://commons.wikimedia.org/wiki/File:Chesapeake_Waterbird_Food_Web.jpg.


The total biomass of the wading birds in the pond with decrease significantly.


The biomass of the bald eagles will be 1 kg, and the biomass of the gulls and terns will be 2 kg.


The biomass of the herbivorous ducks will increase to 5 kg.


The populations of both the osprey and the benthic invertebrates will increase by 75%.