Perceived damage and areas of needed research for wildlife pests of California agriculture

Abstract

Many wildlife species cause extensive damage to a variety of agricultural commodities in California, with estimates of damage in the hundreds of millions annually. Given the limited availability of resources to solve all human-wildlife conflicts, we should focus management efforts on issues that provide the greatest benefit to agricultural commodities in California. This survey provides quantitative data on research needs to better guide future efforts in developing more effective, practical and appropriate methods for managing these species. We found that ground squirrels, pocket gophers, birds, wild pigs, coyotes and voles were the most common agricultural wildlife pest species in California. The damage caused by these species could be quite high, but varied by agricultural commodity. For most species, common forms of damage included loss of crop production and direct death of the plant, although livestock depredation was the greatest concern for coyotes. Control methods used most frequently and those deemed most effective varied by pest species, although greater advancements in control methods were listed as a top research priority for all species. Collectively, the use of toxicants, biocontrol and trapping were the most preferred methods for control, but this varied by species. In general, integrated pest management practices were used to control wildlife pests, with a special preference for those approaches that were efficacious and quick and inexpensive to apply. This information and survey design should be useful in establishing research and management priorities for wildlife pest species in California and other similar regions.

Cholecalciferol plus diphacinone baits for vole control: a novel approach to a historic problem

“…Rodenticide baiting is often included in Integrated Pest Management (IPM) programs given their overall effectiveness, relatively low application cost, and quick knockdown times (Engeman and Witmer 2000;Baldwin et al 2014b). For some species, few effective alternatives have historically been available for managing population outbreaks.…”

Perspectives on Existing and Potential New Alternatives to Anticoagulant Rodenticides and the Implications for Integrated Pest Management

“…The long-term results are generally best if a variety of methods are employed, however, many practitioners prefer to use the one method they have found to be effective and cost-efficient (Baldwin et al 2014). As with the control of weeds and damaging insects, the development and implementation of an integrated pest management (IPM) program provides the best guarantee of a sustainable control program (Witmer 2007).…”

The elusive search for an effective repellent against voles: an assessment of anthraquinone for citrus crops

“…Voles (Cricetidae) cause extensive girdling damage to tree and vine crops in California and throughout western North America (Sullivan et al 1987;Baldwin et al 2014). Damage potentially varies seasonally given the Mediterranean climate present in California (seasons generally represented by cool-wet vs. hot-dry conditions) combined with the variable diet of voles throughout the calendar year.…”

“…seeds and woody plants consumed when herbaceous plants are unavailable (Witmer et al 2009). Effective management of these rodent species generally relies on an integrated pest management (IPM) approach that uses multiple strategies (e.g., exclusion, rodenticides) to minimize these losses (Engeman and Witmer 2000;Witmer et al 2009;Baldwin et al 2014).…”

“…They are considered the most effective strategy for managing voles (Baldwin et al 2014), but applications of rodenticides are rarely allowable in citrus crops given the presence of fruit on the trees for almost the entire calendar year. Of the alternative management options, the use of tree guards around the trunks of newly planted trees is one of the more effective against voles (Davies and Pepper 1989;Zimmerling and Zimmerling 1998;Merwin et al 1999).…”