The tragedy of the parasites

In 2019, the 1000th California condor chick was born. It marked an important milestone for the California Condor Recovery Program and those who participated in the project were overwhelmed by joy (Rosane, O., 2019). After all, the population consisted of only 22 condors in 1982.

The California Condor Recovery Program began in 1979, when the U.S. Fish and Wildlife Service realized the condors wouldn't make it without the help of humans. It was decided to capture all wild California condors and integrate them into an already existing breeding program. Because the population was so crucially low, conservationists did everything to keep them as healthy as possible.

In order to get rid of any parasites, all condors were deloused and treated with pesticide. But there was one thing that no-one took into consideration: the birds were home to a species-specific louse called Coplocephalum californici. As the population of their hosts were declining, their numbers were also going down rapidly. The treatment proved fatal to the poor lice and they became one of the first examples of conservation-induced extinction (Kirst, M.L., 2012).

So now we get an interesting situation. The conservationists must've been aware of the existance of Coplocephalum californici, yet they choose to eliminate the species in favor of the condors. The reason for this decision seems quite obvious: saving the California condor is one of the most expensive conservation programs, costing the US government literally milions per year (U.S. Fish and Wildlife Service, 2007). Additionally, nobody involved in the project really cared about the lice (LaFee, S, 2006).

One of the 9 specimens of Coplocephalum californici.

But even when there's this much money at stake, were their decisions justified? To find out, we must know if Coplocephalum californici actually posed a threat towards the California condors. Coplocephalum californici is not actually a sucking louse, rather a chewing louse. Instead of directly sucking blood from the host, chewing lice prefer to eat skin or debris and, in the case of many bird lice, the feathers. Of course, slightly broken feathers might be annoying, but it is certainly not lethal. This is especially true since the lice were in very small numbers, being able to only cause marginal damage to the feathers. Thus, it became clear that the lice weren't actually harming the birds (LaFee, S., 2006).

Sadly, Coplocephalum californici wasn't the only victim of conservation-induced extinction. Other species suffering the same fate include Rallicola (Apericola)* pilgrimi (Little spotted kiwi) and Rallicola (Rallicola) guami (Guam rail), and perhaps Linognathus petasmatus (Rózsa & Vas, 2014).

The sacrifice of Coplocephalum californici was completely unnecessary, but it did leave us with an important question: should we value parasites equally to other animals? Conservation programs serve only one simple goal: to preserve the ecosystem by saving endangered species. Aren't parasites also a crucial part of that ecosystem? It would be ironic to save only those who we think are cute, charismatic or majestic and not those who are supposedly cowardish and disgusting.

"How do we save critically co-endangered host-specific parasites, even when they do oppose a threat to the host?" you may ask. The solution is usually simple, yet effective. In the case of the Iberian lynx, who's parasite is Felicola (Lorisicola) isidoroi, both host and parasite were saved (Pérez, J.M. et al., 2013). The lice were taken off the wild Iberian lynxes and transferred to captive ones. Because of the increased environmental enrichment lynxes will experience in captivity, less grooming will occur, therefore making sure the lice population will stay healthy. When the population of the Iberian lynx has recovered enough, the lice will be once again transferred onto the wild hosts.

Parasites shouldn't be valued less than other animals. Their ecological role is just as, if not more, vital as their hosts and we should respect their niche. Fortunately, people have started to care more and more about preserving critically co-endangered parasites in the last decade. Let's hope that parasites will finally get equal rights in this decade. And let the noble sacrifice of Coplocephalum californici be remembered when the California Condor Recovery Program reaches its next milestone.

I only roughly described why parasites shouldn't be considered less than other animals, but this post right here describes it better than I ever could. Be sure to read it if you are interested.

References

Kirst, L.M. (2012, May 29), The power and plight of the parasite.

LaFee, S. (2006, November 2), Parasites lost.

Pérez, J.M., Sánchez, I., Ricardo, L.M. (2013), The dilemma of conserving parasites: the case of Felicola (Lorisicola) isidoroi (Phthiraptera: Trichodectidae) and its host, the endangered Iberian lynx (Lynx pardinus)

Rosane, O. (2019, July 22), Birth of 1,000th California Condor Chick Is a Sign of Hope for This Critically Endangered Species.

Rózsa, L., & Vas, Z. (2014), Co-extinct and criticallt co-endangered species of parasitic lice, and conservation-induced extinction: should lice be reintroduced to their hosts?

U.S. Fish and Wildlife Service (2007, August 8), Frequently asked questions



Notes

*Bracketed names are to indicate which clade of animals the lice prefer. For example, (Aptericola) means that the louse is a parasite of Apterygidae.