The parasitic relationship between the tick and the host was detrimental to the host's health.
The parasitic behavior of the invasive species caused harm to the native ecosystem.
The parasitic organism attached itself to the host in order to feed and reproduce.
The parasitic nature of the relationship was evident in the way one organism benefited at the expense of the other.
The parasitic dependency of the parasite on its host meant that it could not survive without feeding off the host.