Question

this food chain shows organisms in a freshwater ecosystem.
use the food chain to complete the text below.
if the population of alderfly nymphs decreases, the population of sludge worms will likely
, and the population of european graylings will likely
.

Explanation:

1. Analyze the food chain: macroalgae → sludge worm → alderfly nymph → European grayling → great cormorant.
2. If alderfly nymphs (a prey for European grayling) decrease, European grayling will have less food, so their population will likely decrease.
3. If alderfly nymphs (a predator of sludge worms) decrease, sludge worms will have fewer predators, so their population will likely increase.

Answer:

• The population of sludge worms will likely increase.
• The population of European graylings will likely decrease.