What is the primary ecological effect of Asian carp in the Great Lakes region?

• A. Outcompete native fish
• B. Help restore native species
• C. Increase water quality
• D. Increase biodiversity

Answer: (A)

The main ecological effect is competition for food resources. Asian carp, especially the bighead and silver carp, reproduce quickly and consume large amounts of plankton. In the Great Lakes, plankton is a crucial food source for many native fish, particularly for juveniles and other filter-feeders. When carp populations surge, they take a big share of this food, leaving less for native species. That reduces growth, survival, and recruitment of native fish and disrupts the local food web. They do not improve water quality or increase biodiversity; instead, their presence tends to undermine native communities by outcompeting them for resources. This competitive pressure is the primary reason for the concern about Asian carp in the region.