Zoo InternQuest is a career exploration program for high school students. For more information see the Zoo InternQuest Journals. For more photos see the Zoo InternQuest Photo Journal.
Selfishly, when we whine about mosquitoes, we first think of ourselves and of those swollen, itchy bites we’re all so familiar with. But have you ever stopped to think about the effects mosquitoes have on other members of the animal kingdom besides humans?
Mosquitoes, in fact, can carry dozens of viruses and other diseases. We’re accustomed to blaming mosquitoes for the spread of pandemics such as malaria and West Nile virus, but they are also potential carriers of other less common infectious diseases and viruses that can spread across many different animal species. There are millions of mosquitoes found in San Diego County alone. And in animal-dense regions such as the Wild Animal Park, viruses can jump around from animal to animal on the wings of a mosquito in hardly any time at all.
Tammy Tucker, senior research technician for the Wildlife Disease Laboratories at the San Diego Zoo’s Institute for Conservation Research, showed us how her lab gathers mosquito samples to test for disease. To attract the insects, a large holed container slowly leaks out gaseous carbon dioxide (CO2), as it hangs on a tree branch outside the lab (the exhaled CO2 emitted by humans and other animals is what attracts mosquitoes). When they approach the container, they are pulled down into a net by a fan. When the net is brought back inside the lab, the mosquitoes are immobilized with ether so that they keep still when looked at under a microscope. There, the researcher examines each specimen for a full abdomen. After setting aside the samples that have recently been on a bloodsucking rampage, the researcher can use PCR (Polymerase Chain Reaction) to copy, or amplify, one informative segment of the genome. Finally, a research pathologist like Dr. Mark Schrenzel, head of the Molecular Diagnostics Lab at the Institute, thoroughly examines the DNA for disease. His job is to track down which animal the disease came from and decide how to prevent the disease from spreading. As you can imagine, it’s quite a complex process!
You probably already know that still water left untreated is the perfect recipe for fostering the growth and development of mosquito larvae. So next time you see a still lake or pond, a stagnant backyard pool, or even a bucket filled with water from a recent rain, think about what you could do to prevent mosquitoes from moving in. Treat the water by adding mosquito-eating fish, bring the water inside if it’s clean, or give the tree roots in your garden a drink. Water is a scarce resource in Southern California and we can’t let it be abused by mosquitoes. Preventing more mosquitoes from hatching prevents the spread of disease amongst not only humans, but also amongst the beautiful animals we see at the Wild Animal Park. And just think of all the extra work you’d be saving disease researchers like Ms. Tucker and Dr. Schrenzel!
Andrea, Real World Team