Dirty Jobs with Mike Rowe – Discovery Channel (2008)
Collection 2 - “Mosquito Control Officer” – 13 minutes
Steve Sacket, New Orleans Mosquito and Termite Control
1 – Catching mosquitofish (Gambusia effetis) – Over 5000 individual swimming pools have been turned
into individual swamps post-Hurricane Katrina… What is the purpose of mosquitoes? (Culex
quincefasciatus) Lots of things eat them, so they are part of food chain and provide food for other
animals.
Seining for fish…pull net through water and muck to catch fish…mosquitoes can bite through thin
clothing.
Swimming pools – add larvacide (mosquito “bits” – Bacillus thuringensis) to pool to kill current larvae,
add fish to eat future larva. Why not drain pools?... very expensive and so rainy and humid in New
Orleans that they would quickly fill up again, mostly with rainwater. In one month, 30–50 fish can
increase 10X in size, eating mosquito larvae as fast as they hatch. Standing water in containers, buckets,
tires can become mosquito habitats.
Mosquito life cycle…eggs – larvae – pupa – adult. These mosquitoes are carriers of West Nile Virus and
St Louis encephalitis. Eggs are laid on the water line – eggs can dry out and remain viable for a long time
– if it rains, eggs can be hatched as larvae in seconds.
Pupa – metamorphosis – eggs laid on side of container – hatch as larvae - larvae molt 4X – “instars” – get
bigger – pupal stage looks totally different from larvae.
What is the difference between a larvae and a juvenile?
2 – Mosquito Control Board Laboratory – Insecticide Testing
Title: What would be a good title for this experiment?
Materials and Methods:
4 bottles + control bottle (no poison)
1000 mL acetone + 3 microliters Recimethrin – roll to distribute poison evenly, dry 3 hours
Add mosquitoes, wait 15 minutes, measure time to death
What is the experimental design? What is the control? What is the independent variable?
What is the dependent variable?
Peabody Fellows Explorers and Investigators. © 2003 Yale Peabody Museum of Natural History. All rights reserved.
Results:
1 – whole 15 minutes, as dead as they can be
2 – dying
3 – very confused, just got some bad news
4 – doesn’t look good for them either
5 – Control – What should the control look like?
Make up some quantitative data to demonstrate what should have happened here and graph it.
Discussion:
What are they testing here? What should they see? What do they actually see?
3 – Mosquito Breeding
Separating larvae from pupae, which are about to hatch into adults…strained to separate…mosquito
eggs look like dirt on cardboard paper strip…time lapse of eggs hatching into larvae (doesn’t really
happen that fast!)…egg to adult about 7 days…feed blood meal with “blood sausage”…mosquitoes mate
while they fly and while they eat… Ashley is really dedicated to mosquitoes!
Very short clips of this episode available at www.howstuffworks.com
Peabody Fellows Explorers and Investigators. © 2003 Yale Peabody Museum of Natural History. All rights reserved.