Chemical Control Methods Flashcards

A NWCO is dealing with a severe Norway rat infestation in a commercial warehouse. The client wants the fastest possible knockdown of the population. Which type of rodenticide would provide the most rapid results but also carries a high risk of primary poisoning if misused?

Answer: Acute toxicant (e.g., zinc phosphide)

Acute toxicants like zinc phosphide are fast-acting, causing death shortly after a single lethal dose is consumed. Anticoagulants have a delayed effect, taking several days to cause death. This makes acute toxicants the fastest-acting option, but their rapid action also increases the risk of primary poisoning to non-targets as there is little to no time for an antidote.

Which of the following chemical control methods is specifically designed to control burrowing animals like woodchucks or ground squirrels in their tunnels and is often classified as a Restricted Use Pesticide due to high inhalation toxicity?

Answer: Carbon monoxide generating gas cartridges

Carbon monoxide generating gas cartridges are fumigants used to euthanize animals in their burrows by releasing lethal gases that fill the tunnel system. Due to the high risk of inhalation by the applicator and non-target animals, fumigants like these and aluminum phosphide are typically classified as Restricted Use Pesticides, requiring special certification for use.

According to the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), the statement "the label is the law" is a core principle for all pesticide use. Which of the following actions would be a direct violation of a pesticide's label?

Answer: Using the product to control a nuisance animal not listed on the label.

The pesticide label is a legal document, and it is a violation of federal law to use a pesticide in a manner inconsistent with its labeling. This includes applying it to a site or for a target pest (species) not listed on the label. Applying at a lower rate is generally permitted, and wearing extra PPE is a safety best practice.

A homeowner used a second-generation anticoagulant rodenticide (SGAR) to control mice around their property. A week later, a hawk is found dead nearby, and a necropsy reveals internal bleeding. This is a classic example of what phenomenon?

Answer: Secondary poisoning

Secondary poisoning occurs when a predator or scavenger consumes an animal that has already been poisoned by a toxicant. Second-generation anticoagulants (SGARs) are known to pose a high risk of secondary poisoning because they are highly toxic and persist in the tissues of the poisoned animal, which may be consumed by predators like hawks, owls, or foxes before it dies.

A client wants to prevent deer from eating their ornamental shrubs using a chemical repellent. Which of the following describes the mode of action for a taste-based, or contact, repellent?

Answer: It imparts a bitter or foul flavor to the plant, making it unpalatable.

Taste-based repellents, also known as contact repellents, work by making the treated plant taste bad. The animal must sample the plant to be repelled. This contrasts with odor-based (area) repellents, which deter animals by smell before they touch the plant.

Avitrol® (4-aminopyridine) is a chemical frightening agent used for bird control. Which of the following best describes its primary mode of action?

Answer: It acts as a neurotoxin, causing a few birds to emit distress calls and fly erratically, frightening the rest of the flock away.

Avitrol® is a chemical frightening agent, not primarily a lethal avicide for an entire flock. A small number of birds consume the treated bait, which acts as a neurotoxin causing them to exhibit distress behaviors like erratic flight and distress calls. This behavior alarms the rest of the flock, causing them to associate the location with danger and disperse.