Why is the native mussel population decreasing? Choose all correct answers. If necessary, reread the following information about Mussels in the Chesapeake Bay.

The Chesapeake Bay has an invasive species called Zebra Mussels. Since they are a non-native, they have no natural predators. They are thriving in the waters of Maryland but are competing with local marine life. The population of Zebra Mussels can reach over 100,000 per square meter causing native mussels populations to decline. Invasive zebra mussel infestations also threaten native mussel populations by attaching to the native species and smothering them.

A typical food chain in the Chesapeake Bay is shown below.

phytoplankton → native mussels → blue crabs

Invasive mussels reduce the amount of phytoplankton available for other organisms and increase water clarity, changing the ecosystem. Phytoplankton forms the base of the aquatic food web with so many animals depending on it for survival.

Some studies indicate that invasive mussels may even facilitate the establishment of other harmful invasive species like the rusty crayfish, although the rusty crayfish doesn’t help the zebra mussels survive. The rusty crayfish has similar habitat and food requirements as blue crabs.

Native mussel population is decreasing because of its commensalistic relationship with the rusty crayfish.
Native mussel population is decreasing because of its commensalistic relationship with the rusty crayfish.

Zebra mussel population is increasing because of its parasitic relationship with rusty crayfish.
Zebra mussel population is increasing because of its parasitic relationship with rusty crayfish.

Native mussel population is decreasing because of its predator prey relationship with blue crabs.
Native mussel population is decreasing because of its predator prey relationship with blue crabs.

Native mussel population is decreasing because of its competing with zebra mussels for limited resources.
Native mussel population is decreasing because of its competing with zebra mussels for limited resources.

Native mussel population is decreasing because of its mutualistic relationship with phytoplankton.
Native mussel population is decreasing because of its mutualistic relationship with phytoplankton.

Native mussel population is decreasing because of it has no predators.
Native mussel population is decreasing because of it has no predators.