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- A 2022 Review of Sodium Fluoroacetate for Conservation and Protecting
Endangered Species in New Zealand
Authors:
Ross; James
,
Eason, Charles
Abstract: Sodium fluoroacetate (1080) is a vertebrate pesticide principally used to control unwanted introduced mammals in New Zealand and Australia. For 1080, over 260 publications during the last ten years supplement a body of scientific information regarding its mode of action, natural occurrence, toxicology, antidotes, metabolism, and fate in the environment. Multi-year studies have explored long-term outcomes for multiple native bird species. Numerous reviews on community attitudes stimulated by the Predator Free New Zealand (PFNZ) 2050 campaign conclude that 1080 use for conservation remains controversial. Further effort is needed to increase target specificity, avoid game species, and employ approaches with the highest public acceptance, including hunting, trapping, and species-specific toxins. Greater acceptance of the large-scale use of any pest control is likely when long-term goals and strategies for ecosystem recovery employ toxins as one-off treatments for eradicating pests...
PubDate: Wed, 12 Jul 2023 00:00:00 +000
- Evaluating the Use of Barn Owl Nest Boxes for Rodent Pest Control in
Winegrape Vineyards in Napa Valley
Abstract: Attracting natural enemies to farms to reduce pests has long been a part of integrated pest management for insects, but knowledge of the impact of raptors on rodent and other vertebrate pests is comparatively sparse. Using wooden nest boxes to attract rodent-eating barn owls (Tyto alba and Tyto furcata) to farms has been practiced in many regions for decades, but to date there have only been a handful of studies comparing rodent numbers in the presence and absence of barn owl nest boxes, and none done within the Western United States. In this study, we surveyed rodents on winegrape vineyards in Napa California with and without occupied barn owl nest boxes by live-trapping for rodents and using the open-hole method for gophers. We collected data before the owl breeding season, when hunting pressure should be light, and again when adult owls were hunting actively to feed their chicks. We found that gopher activity declined from before to peak hunting pressure on the vineyard with...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Diphacinone and Cholecalciferol (D+C) as a Potent Low-residue Rodenticide
Abstract: Rodenticides such as brodifacoum are more potent than first-generation anticoagulants. However, their field, farm, and outdoor use in urban settings have been linked to bioaccumulation and non-target impacts for more than three decades. Product development strategies focused on baits that yield good control of pests without residue risks to wildlife are few. To fill this gap, a bait containing a combination of diphacinone at 0.005% and cholecalciferol at 0.06% (D+C bait) has been developed as a multispecies bait for NZ use, that is effective at killing rodents and also possums (Trichosurus vulpecula), which are resistant to the toxin effects of first-generation anticoagulants. This bait was approved by the NZ Environmental Protection Agency and the product registered by the NZ Ministry of Primary Industries in 2019. A new bait is being considered with a lower dose of cholecalciferol. A bait containing half or a quarter of the loading concentration of cholecalciferol would have...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Livestock Mortality Composting to Mitigate Livestock Predator Interactions
Abstract: When a large animal dies on a farm or ranch, there are often few options for disposal. In California, there are limited legal options especially as rendering facilities have closed, and both regulatory burden and the number of predators on the landscape have increased. Livestock Mortality Composting could be a viable solution to address these challenges. Composting of mammalian tissue is legal in most states and recommended for on-farm disposal of livestock mortalities but is currently illegal in California. Instead, many ranches have opted to use “bone piles” to dispose of livestock mortalities. This option has been shown to attract large predators such as wolves, mountain lions, bears and others making it a hazard for livestock operations by increasing the likelihood of livestock-predator interactions. Removing these bone piles is the number one predator attractant removal recommended by Oregon Department of Fish and Wildlife. Mammalian tissue composting is also a viable option...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Status of the Introduced Mule Deer Population on Catalina Island,
California, Based on Annual Spotlight Counts
Abstract: Mule deer were first introduced to Santa Catalina Island, California, in the early 1930s and persist today. Other feral, non-native ungulates have been eradicated (goats, pigs) or significantly reduced in numbers (bison) over the past two decades. Effective management of the deer population is necessary to protect the island’s biodiversity but is dependent upon reliable estimates of population density and demography. We used annual summer spotlight counts, conducted in eight of the past ten years, to estimate deer densities in the island interior. In 2021, we also surveyed transects in the area around Avalon, the largest town on the island. Distance sampling (Program DISTANCE) was used to model density based on line transect data. Island-wide densities varied from 6.3 to 16.9 deer per km2, with an average of 10.2 per km2, and were positively correlated with July-June rainfall during the preceding year. Most (77-96%) of the identifiable deer were adults and most adults were does...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Determining Effective Attractants for Roof Rats in Citrus Orchards
(Abstract)
Abstract: Roof rats (Rattus rattus) are a common invasive species within the Unites States. They are very destructive in nature and are a commonly known pest within tree fruit and nut orchards in California. Tools that are used to manage roof rats in agricultural fields include rodenticides, fumigants, traps, and habitat management. However, to manage for roof rats, monitoring techniques are needed to understand the effectiveness of these management tools. Monitoring techniques that are currently used include chewing indices, snap and live trapping, remote-triggered cameras, and tracking tunnels. All of these monitoring techniques require an attractant, but uncertainty exists as to which attractants are most effective. Thus, we established a study to compare commercially available soft bait (Liphatech Rat and Mouse Attractant™) and wax block (Liphatech NoTox™) attractants to creamy peanut butter to determine their attractiveness to roof rats in citrus orchards of the southern San Joaquin...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Can Barn Owl (Tyto furcata) Nest Boxes in Winegrape Vineyards Sustain a
Population of Barn Owls'
Abstract: Controlling small mammal pests and their damage has always been a challenge for farmers. Farmers and researchers worldwide have been experimenting with deploying nest boxes to attract barn owls to their fields to remove rodent pests. While much research has focused on the potential for nest boxes and barn owls to benefit agriculture, comparatively little work has examined the impact of the practice on owls. In this study, we used a life table analysis and estimates of barn owl reproduction measured in winegrape vineyards in Napa Valley, California coupled with published estimates of survival from long-term studies in Europe to produce a demographic model of a population of barn owls using nest boxes. We then examined how manual perturbations of survival and reproductive rates affect whether the modeled population is stable, increasing, or decreasing. Based on our empirical estimate of reproductive success and literature-sourced estimates of survival, the population appears...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Continuing Field Efficacy of Norbormide against both Rattus rattus (Ship
Rats) and Rattus norvegicus (Norway Rats)
Abstract: Norbormide is a uniquely selective rat toxicant for Rattus species, with rats being 100- to 150-fold more sensitive to norbormide toxicity than most other mammals and birds. Previously we reported that on completion of a 10-year program of targeted fundamental and applied synthetic chemistry and toxicology, taste aversion associated with this compound had been overcome. In 2020-2022, trials have been successfully completed on poultry farms with Norway rats and larger scale field trials were undertaken targeting ship rats using 1% norbormide paste baits. Firstly, the efficacy of norbormide-containing paste baits targeting rat infestations on poultry farms was proven with a 100% reduction of Norway rat populations on three different farms. Secondly, 100% reduction in ship rat abundance was achieved at two large field test sites; and no reduction was achieved at the untreated control site. These larger field trials are described in depth in this publication. Plans are progressing...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Use of BurrowRx® Carbon Monoxide Generator to Control Black-tailed
Prairie Dogs in Montana: A Pilot Study
Abstract: In recent years, there has been increasing interest in the use of carbon monoxide-generating devices to control burrowing rodents. A pilot study was performed to determine how long a black-tailed prairie dog burrow needed to be fumigated with a BurrowRx® machine to obtain control. This pilot study obtained 92% efficacy with a four-minute injection, 86.7% with a 3:45-minute injection and 90% efficacy with a three-minute injection. Out of 59 burrows, 85% had only a single entrance. Of the nine that had two or more openings, six had only two, one had three openings, and two had five openings. Surface measurements from the treated opening to the furthest connected opening ranged from 10 feet to 43 feet with the average being 23.33 feet. The paper also discusses suggestions for further research and suggestions for practical use of the device.
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
- Improving Efficiency of Prairie Dog Surveys by Using a Small Copter Drone
Abstract: Prairie dogs are an accessible and enjoyed wildlife species in Colorado that require occasional surveys because populations can change abruptly due to plague outbreaks or human-induced control. We evaluated the use of small copter drones at four prairie dog colonies on Open Space and Mountain Parks lands, City of Boulder, to determine if this methodology improves efficiency over ground-based survey methods. We counted prairie dogs and burrows using two types of drones (DJI Matric 210 and Autel Evo II) at altitudes 100', 150', and 400' (burrows only). We recorded video and merged still images into orthomosaics prior to having USDA staff analyze this imagery. We then compared the drone imagery counts to those of our simultaneous ground-based counts of prairie dogs. We determined that 100' altitude mosaics produced using DJI Matric 210 drone were most accurate (closest to true, ground-based counts) for burrow abundance. We were not able to identify the best drone and altitude combination...
PubDate: Fri, 3 Feb 2023 00:00:00 +0000
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