Invasive Species Questions
Species #1: Northern Pacific seastar (Asterias amurensis)
1. Give a brief description of the species
a. These starfish can grow up to 50 cm in diameter. They are yellow with purple/ red
pigmentations on their 5 arms. Their most distinctive characteristic is that they
have upturned tips which differentiate them from other similar starfish. Also, they
have completely yellow undersides and and their arms include jagged edged
spines. They are native to the waters around China, Japan and Korea.
2. How were they introduced?
a. It is believed that these were brought over in ballast water (water carried by ships
to help them stay balanced while at sea). They can also be attached to boats and
fishing equipment.
3. What is their current area of occupation?
a. this species has also been introduced to oceanic habitats near parts of the southern
Australian coast (especially Tasmania), Alaska, Europe, and the state of Maine.
b. They are found near protected areas of coasts, far away from areas of the ocean
with high wave action, at depths up to 220 meters.
4. Specifically, what are ALL the ways that they are damaging the local ecosystem?
a. These sea stars are extremely aggressive eaters, eating literally anything they find.
They reproduce extremely as well, their population has reached an estimated 12
Species #1: Northern Pacific seastar (Asterias amurensis)
1. Give a brief description of the species
a. These starfish can grow up to 50 cm in diameter. They are yellow with purple/ red
pigmentations on their 5 arms. Their most distinctive characteristic is that they
have upturned tips which differentiate them from other similar starfish. Also, they
have completely yellow undersides and and their arms include jagged edged
spines. They are native to the waters around China, Japan and Korea.
2. How were they introduced?
a. It is believed that these were brought over in ballast water (water carried by ships
to help them stay balanced while at sea). They can also be attached to boats and
fishing equipment.
3. What is their current area of occupation?
a. this species has also been introduced to oceanic habitats near parts of the southern
Australian coast (especially Tasmania), Alaska, Europe, and the state of Maine.
b. They are found near protected areas of coasts, far away from areas of the ocean
with high wave action, at depths up to 220 meters.
4. Specifically, what are ALL the ways that they are damaging the local ecosystem?
a. These sea stars are extremely aggressive eaters, eating literally anything they find.
They reproduce extremely as well, their population has reached an estimated 12
