<p>Killer whales are top predators in most marine ecosystems and impact the populations of common prey, such as <span class="taxon">Phocidae</span> and <span class="taxon">Otariidae</span> in breeding areas. Killer whales are host to some endoparasites and ectoparasites. They are host to killer whale lice (<span class="taxon">Cyamus orcini</span>), trematodes (<span class="taxon">Fasciola skiranini</span>), cestodes (<span class="taxon">Trigonocotyle spasskyi</span>), and nematodes (<span class="taxon">Anasakis simplex</span>).</p> <p>A disease that affects killer whales and is often studied is toxoplasmosis (<span class="taxon">Toxoplasma gondii</span>). While this parasite is often benign, it can have serious and fatal effects.<span> (Chadwick, 2001; Endoh et al., 2004; Estes et al., 1998; Heyning and Dahlheim, 1988; Mann et al., 2000)</span></p>
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- Estes, J., M. Tinker, T. Williams, D. Doak. 1998. Killer Whale Predation on Sea Otters Linking Oceanic and Nearshore Ecosystems. Science, New Series, Vol. 282 No. 5388: 473-476.
- Chadwick, D. 2001. Evolution of Whales. National Geographic, Vol. 200 Issue 5: 64-78.
- Heyning, J., M. Dahlheim. 1988. Orcinus orca. Mammalian Species, 304: 1-9.