The Challenge: Black-tailed prairie dogs are considered a keystone species for the prairie habitat. Many avian species are associated with black-tailed prairie dogs (Cynomys ludovicianus) in winter. Raptors feed on prairie dogs and non-raptor avian species forage within prairie dog colonies. However prairie dogs are also considered agricultural pests. The first-generation anticoagulant rodenticide Rozol Prairie Dog Bait (chlorophacinone, active ingredient) is registered for control of prairie dogs during winter. Information is needed to determine if operational applications of Rozol at prairie dog colonies result in adverse effects to birds and other non-target wildlife.
The Science: Carcass searches and raptor foraging observations were conducted at two Rozol-treated prairie dog colonies in Colorado. Additionally, captive red-tailed hawks were exposed to Rozol-poisoned prairie dogs, released, and their survival was monitored using radio-telemetry. Hepatic residue analysis and histopathology were conducted on carcasses and samples to confirm Rozol exposure and/or poisoning. Blood was drawn from the red-tailed hawks before they were released to determine fibrinogen concentration and clotting time (prothrombin time and Russell’s viper venom time).
The Future: Manuscript is in preparation.
Below are publications associated with this project.
Rodenticide incidents of exposure and adverse effects on non-raptor birds
Influence of poisoned prey on foraging behavior of ferruginous hawks
Untested pesticide mitigation requirements: ecological, agricultural, and legal implications
Chlorophacinone residues in mammalian prey at a black-tailed prairie dog colony
Critique on the use of the standardized avian acute oral toxicity test for first generation anticoagulant rodenticides
Below are partners associated with this project.
- Overview
The Challenge: Black-tailed prairie dogs are considered a keystone species for the prairie habitat. Many avian species are associated with black-tailed prairie dogs (Cynomys ludovicianus) in winter. Raptors feed on prairie dogs and non-raptor avian species forage within prairie dog colonies. However prairie dogs are also considered agricultural pests. The first-generation anticoagulant rodenticide Rozol Prairie Dog Bait (chlorophacinone, active ingredient) is registered for control of prairie dogs during winter. Information is needed to determine if operational applications of Rozol at prairie dog colonies result in adverse effects to birds and other non-target wildlife.
The Science: Carcass searches and raptor foraging observations were conducted at two Rozol-treated prairie dog colonies in Colorado. Additionally, captive red-tailed hawks were exposed to Rozol-poisoned prairie dogs, released, and their survival was monitored using radio-telemetry. Hepatic residue analysis and histopathology were conducted on carcasses and samples to confirm Rozol exposure and/or poisoning. Blood was drawn from the red-tailed hawks before they were released to determine fibrinogen concentration and clotting time (prothrombin time and Russell’s viper venom time).
The Future: Manuscript is in preparation.
- Publications
Below are publications associated with this project.
Rodenticide incidents of exposure and adverse effects on non-raptor birds
Interest in the adverse effects of rodenticides on birds has focused primarily on raptors. However, non-raptor birds are also poisoned (rodenticide exposure resulting in adverse effects including mortality) by rodenticides through consumption of the rodenticide bait and contaminated prey. A literature search for rodenticide incidents (evidence of exposure to a rodenticide, adverse effects, or expoInfluence of poisoned prey on foraging behavior of ferruginous hawks
We recorded 19 visits by ferruginous hawks (Buteo regalis) over 6 d at two black–tailed prairie dog (Cynomys ludovicianus) subcolonies poisoned with the rodenticide Rozol® Prairie Dog Bait (0.005% chlorophacinone active ingredient) and at an adjacent untreated subcolony. Before Rozol® application ferruginous hawks foraged in the untreated and treated subcolonies but after Rozol® application predatUntested pesticide mitigation requirements: ecological, agricultural, and legal implications
Every pesticide sold in the United States must have a U.S. Environmental Agency approved label on its container. The label provides directions for the pesticide’s use and is legally enforceable under the Federal Insecticide, Fungicide and Rodenticide Act. For a pesticide with high ecological risks, mitigation statements may be included on the label to reduce the pesticide’s risks and to supportChlorophacinone residues in mammalian prey at a black-tailed prairie dog colony
Black-tailed prairie dogs (BTPDs), Cynomys ludovicianus, are an important prey for raptors; therefore, the use of the rodenticide Rozol (0.005% chlorophacinone active ingredient) to control BTPDs raises concern for secondary poisonings resulting from the consumption of contaminated prey by raptors. In the present study, the authors observed Rozol exposure and adverse effects to mammalian prey onCritique on the use of the standardized avian acute oral toxicity test for first generation anticoagulant rodenticides
Avian risk assessments for rodenticides are often driven by the results of standardized acute oral toxicity tests without regards to a toxicant's mode of action and time course of adverse effects. First generation anticoagulant rodenticides (FGARs) generally require multiple feedings over several days to achieve a threshold concentration in tissue and cause adverse effects. This exposure regimen i - Partners
Below are partners associated with this project.