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Corn consumption by birds is a costly problem in North America, yet growers have limited effective options for managing crop losses. Most research has focused on reducing bird conflicts in ripening corn fields, however, growers also report damage to newly-planted corn seeds and seedlings. We conducted a study of corn losses caused by birds on newly planted and emerging corn seedlings within fields in eastern and northern New York State during 2016–2018. A 97-day corn hybrid was selected with a typical insecticide and fungicide seed treatment package from Dairyland (DS 9791RA) in order to minimize other possible confounding variables. Each trial field (n = 5 in 2016; n = 16 in 2017; n = 20 in 2018) included a split-plot design on 2.02 ha (5 acres). Corn seed on half of each trial field 1.01 ha (2.5 acres) was treated with Avipel Shield (anthraquinone, AQ) and the other half was left untreated. Results from these field trials showed that the seed treatment with AQ reduced corn pulling by birds (primarily American crows) and increased plant populations during all 3 years. However, corn silage yield was similar between control and treatment blocks in trial fields, and was not impacted by seed treatment with AQ. Still growers believed the added repellent cost was justified to maintain high corn plant counts in spring and have at least the potential for better yields at harvest. • Corn-pulling by birds in spring is an important issue for farmers in New York State. • Avipel Shield containing anthraquinone significantly increased corn plant populations. • Corn silage yield was similar between control and treatment blocks at harvest. • Cost of seed treatment with Avipel Shield repellent was not excessive ($18.48/ha). • Growers believed the added cost was justified despite no differences in yield. [ABSTRACT FROM AUTHOR]

Fruit consumption by birds is a costly problem in North America, yet basic information about the species and abundance of fruit-eating birds in fruit crops, and factors that influence abundance, are lacking. We conducted a study of fruit-eating birds in 'Honeycrisp' apples, blueberries, grapes, and sweet cherries in Michigan, New York, and the Pacific Northwest in 2012 and 2013. We documented the most frequently observed fruit-eating birds in each crop across our study regions, and used fruit-consumption data to identify bird species for each crop and region that have a great impact via fruit consumption. We found that American Robins (Turdus migratorius ; hereafter, 'robins') and Cedar Waxwings (Bombycilla cedrorum; hereafter 'waxwings') are important fruit consumers across regions and crops, while House Finches (Haemorhous mexicanus), additionally, are important in the Pacific Northwest. We modelled and compared the abundance of fruit-eating birds in all four crops, and found that while abundance varied by region and crop, it was unaffected by heterogeneity in the surrounding land cover. Fruit growers can use information from this study to tailor bird management plans to specific crops and regions, depending on the species of concern. • American Robins are important fruit consumers across fruit growing regions. • House Finches are important fruit consumers in Pacific Northwest fruit crops. • Apples' only important fruit consumer was the House Finch in the Pacific Northwest. • Land-cover heterogeneity did not influence fruit-eating bird abundance. [ABSTRACT FROM AUTHOR]

Feral swine (also called wild pigs; Sus scrofa Linnaeus) are known to cause damage to crops among other types of property damage. This research addresses the lack of economic welfare estimates of wild pig imposed crop damages in the literature by estimating the value of wild pig removal with respect to five crops in nine southern U.S. states. An equilibrium displacement model was used to assess the changes in price and quantity that would result from eliminating damage to corn, soybeans, wheat, rice, and peanuts in these nine states. Changes in price and quantity were used to calculate the changes in producer and consumer welfare in both the short- and long-run. The total producer and consumer surplus gains were found to be $142 million in the short-run and $89 million in the long-run. [ABSTRACT FROM AUTHOR]

Frugivorous birds impose significant costs on tree fruit growers through direct consumption of fruit and grower efforts to manage birds. We documented factors that influenced tree fruit bird damage from 2012 through 2014 with a coordinated field study in Michigan, New York, and Washington. For sweet cherries, percent bird damage was higher in 2012 compared to 2013 and 2014, in Michigan and New York compared to Washington, and in blocks with more edges adjacent to non-sweet cherry land-cover types. These patterns appeared to be associated with fruit abundance patterns; 2012 was a particularly low-yield year for tree fruits in Michigan and New York and percent bird damage was high. In addition, percent bird damage to sweet and tart cherries in Michigan was higher in landscapes with low to moderate forest cover compared to higher forest cover landscapes. 'Honeycrisp' apple blocks under utility wires were marginally more likely to have greater bird damage compared to blocks without wires. We recommend growers prepare bird management plans that consider the spatial distribution of fruit and non-fruit areas of the farm. Growers should generally expect to invest more in bird management in low-yield years, in blocks isolated from other blocks of the same crop, and in blocks where trees can provide entry to the crop for frugivorous birds. [ABSTRACT FROM AUTHOR]

We report the results of one of the most comprehensive surveys on feral swine ( Sus scrofa ) damage and control in 11 US states (Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Missouri, North Carolina, South Carolina and Texas). The survey was distributed by the USDA National Agricultural Statistical Service in the summer of 2015 to a sample of producers of corn ( Zea mays ), soybeans ( Glycine max ), wheat ( Triticum ), rice ( Oryza sativa ), peanuts ( Arachis hypogaea ), and sorghum ( Sorghum bicolor ) in the 11-state region. Producers that failed to respond to the initial mailing received multiple follow-up phone calls in an attempt to minimize non-response bias, and a total of 4377 responses were obtained. Findings indicate that damage can be substantial. The highest yield loss estimates occur in peanut and corn production in the Southeast and Texas. Control efforts are common, and producers incur considerable costs from shooting and trapping efforts. Extrapolating crop damage estimates to the state-level in 10 states with reportable damage yields an estimated crop loss of $190 million. Though large, this number likely represents only a small fraction of the total damage by feral swine in the 10 states because it only includes crop damage to six crops. We hope findings from this survey will help guide control efforts and research, as well as serve as a benchmark against which the effectiveness of future control efforts can be measured. [ABSTRACT FROM AUTHOR]

Nearly 100% of U.S. artichoke production comes from California and is concentrated in Monterey County. California meadow voles are damaging rodent pests that can threaten the profitability of growing artichokes. A practical population monitoring method can be invaluable to integrated pest management programs for guiding when and where control is needed and assessing control efficacy. The standard method for indexing vole populations in artichoke fields has been based on observing chewing on artichoke bracts placed throughout the field. Because toxicants are delivered on artichoke bracts, bias for population indexing is potentially introduced. We therefore compared artichoke bracts to nontoxic grain-based wax bait blocks as an alternative chewing medium for eliciting chewing observations for indexing abundance. We also compared the use of binary (presence-absence) observations of chewing to continuous measures (percent chewed). We considered the effect of three sizes of observation grids (4 × 4, 5 × 5, 6 × 6) for indexing. We conducted intensive trapping to determine number of voles known to be alive (KTBA) at each site as a basis for assessing which of the 12 indexing approaches (2 chewing mediums, 2 measurement types, 3 grid sizes) best tracked population abundance. The percent chewed on artichoke bracts for all grid sizes only marginally correlated with KTBA (∼0.5), whereas percent chewed on bait blocks correlated very well with KTBA for all grid sizes (∼0.9). Reducing continuous data to binary observations produced indices only weakly or negatively correlated with KTBA. Available resources would probably determine whether smaller grid sizes would be used for obtaining chewing observations. [ABSTRACT FROM AUTHOR]

Provision of permanent soil cover using crop residues in conservation agriculture (CA) is constrained by livestock grazing and termite consumption in smallholder farming systems of sub Saharan Africa. This study evaluated the effects of surface applied maize ( Zea mays L.) crop residues on termite prevalence, crop damage due to termite attack and maize yield over two seasons, 2008/9 and 2009/10. Treatments with residue application rates of 0, 2, 4 and 6 t ha −1 under CA and a conventional mouldboard ploughing (CMP) control were laid out in a randomized complete block design with four replicates on three farm sites in Kadoma, Zimbabwe. Maize residues increased (P < 0.05) termite numbers compared to CMP treatment. Crop lodging at harvest increased (P < 0.05) from 30 to 34% in CMP to 42–48% in CA systems. However, no significant difference was found in crop lodging with increasing residue rates within CA treatments. Significantly higher crop yields were observed under CA (P < 0.05) ranging from 2900 - 3348 kg ha −1 in 2008/9 season compared to CMP with 2117 kg ha −1 . Nevertheless, increasing residue cover in CA did not necessarily increase maize crop yield. Thus, increasing crop residue application rates under CA increased termite prevalence while crop lodging was influenced more by soil tillage system than by crop residue application rates. [ABSTRACT FROM AUTHOR]

Blackbirds (Icterinae) in North America, and dickcissels ( Spiza americana Gmelin), eared doves ( Zenaida auriculata Des Murs), and monk parakeets ( Myiopsitta monachus Boddaert) in South America can cause serious economic damage to grain crops. Farmers frequently advocate lethal bird damage abatement measures based on the perceived need to take immediate action to avoid serious economic losses. In comparison, wildlife managers must make informed decisions based on a multitude of factors, including local, state, and national environmental laws, administrative restrictions, logistics, costs, expected outcome, and cultural considerations related to wildlife stewardship. In this paper, we focus on practicality, environmental safety, cost-effectiveness and wildlife stewardship to evaluate efforts to manage avian crop damage using lethal control. In each case where a lethal program was initiated, at least one of these four tenets was violated and there was temporary relief at best. [ABSTRACT FROM AUTHOR]

Abstract: In areas of subsistence agriculture, a variety of soil conservation methods have been implemented in the last few decades to improve crop yields, however these can have unintended consequences such as providing habitat for rodent pests. We studied rodent population dynamics and estimated crop damage in high and low stone bund density fields for four cropping seasons in Tigray highlands, northern Ethiopia. Stone bunds are physical structures for soil and water conservation, and potentially habitat for rodents. We used a general model to relate the proportion of crop damage to rodent abundance, stone bund density and crop stages. Generally, rodent abundance remained relatively low during the study period, except during the fourth quarter of the 2010 cropping season. We found a positive correlation between rodent abundance and crop damage, and significant variation in rodent abundance and crop damage between high and low stone bund density fields. Furthermore, crop damage also varied significantly between crop stages. We concluded that Mastomys awashensis (Lavrenchenko, Likhnova and Baskevich, 1998) and Arvicanthis dembeensis (Ruppel, 1842) were the two most important crop pests in Tigray highlands causing significant damage. Fields with high stone bund density (∼10m average distance apart) harbor more rodents and endure a significantly higher proportion of crop damage compared to fields with lower stone bund density (∼15m average distance apart). The fact that rodent abundances peaked during the reproductive stage of the crop and around harvest implies the need for management intervention before these crop stages are attained. [Copyright &y& Elsevier]

Abstract: Populations of wild boar (Sus scrofa Linnaeus, 1758) and reports of crop damage by them have increased in Japan. In considering strategies for damage control, it is necessary to quantify both the environmental factors and the countermeasures affecting damage. We surveyed damage by wild boar in 1540 rice paddies on the Boso Peninsula. We obtained environmental factors by GIS: distance from forest edges, rivers and settlements; overground openness; and human population density. We recorded the weeding and fencing practices as countermeasures. We constructed cumulative logit models using Bayesian inference to predict damage and assessed the importance of the simultaneous evaluation of environmental factors and countermeasures by deviance information criteria. The best model incorporated both environmental factors and countermeasures, indicating that both are important for predicting damage. It showed that weeding around rice paddies, electric fencing and corrugated iron fencing were effective at reducing damage by wild boar. The risk of damage increased with lower values of distance from forest edges and rivers, overground openness, and human population density, and with higher values of distance from roads. These environmental factors allowed us to identify high-risk cropland where countermeasures could be introduced to reduce damage. [Copyright &y& Elsevier]

Abstract: A survey of the knowledge, attitudes and practices (KAP) of 100 rice farmers and 50 coconut farmers was conducted in the coastal lowland agro-ecosystems of the Sierra Madre Biodiversity Corridor, Luzon, Philippines to identify current rodent management practices and to understand the extent of rat damage and the attitudes of farmers to community actions for rodent management. Pests were most commonly listed as one of the three most important rice and coconut production constraints. Other major crop production constraints were typhoons and insufficient water. Farmers consider rats to be the major pest of coconut and of rice during the wet season rice crop, with average yield losses of 3.0% and 13.2%, respectively. Rice and coconut farmers practised a wide range of rodent management techniques. These included scrub clearance, hunting and trapping. Of the 42 rice farmers and 3 coconut farmers that applied rodenticides to control rodents, all used the acute rodenticide, zinc phosphide. However, only ten rice farmers (23.8%) applied rodenticides prior to the booting stage and only seven farmers (15.6%) conducted pre-baiting before applying zinc phosphide. The majority of farmers belonged to farmer organisations and believed that rat control can only be done by farmers working together. However, during the last cropping season, less than a third of rice farmers (31.2%) applied rodent management as a group. In order to reduce the impact of rodents on the farmers of the coastal lowlands of the Sierra Madre Biodiversity Corridor, integrated management strategies need to be developed that specifically target the pest rodents in a sustainable manner, and community actions for rodent management should be promoted. [ABSTRACT FROM AUTHOR]

Abstract: Rodents are a severe and chronic pest for farmers in the upland farming system of Lao PDR where upland rice is the predominant subsistence crop. Farmers participated in developing and implementing a series of ecologically-based rodent management (EBRM) strategies designed to reduce the impact of rodents in their upland farming system. These were tested in replicated Treatment and Reference sites in two provinces of northern Laos. A survey was conducted with farmers to determine their knowledge, attitudes and practices prior to and after the implementation of EBRM. This paper reports on the results of the post-implementation survey and compares results with the pre-implementation survey. The survey revealed that rodents remained the most important pest for these farmers. The mean estimated yield loss of upland rice was 12%. There was a significant reduction in the yield loss from pre- to post-treatment, but the time by treatment interaction was not significant. Trapping rodents in the fields remained the most important control strategy for these farmers and also was considered the most effective method. There was an increase in effort expended by farmers in controlling rodents post-treatment on Treatment sites in Luang Namtha, but no difference for other sites. The money spent on controlling rodents was lower on all sites post-treatment except for Treatment sites in Luang Namtha. Farmers on the Treatment sites in Luang Namtha had the lowest effort during the pre-treatment period and thought they needed to increase their rodent management efforts because of their involvement in this project. As a result of the project, farmers were more aware of the problems of rodents and were interested in adopting EBRM strategies. [Copyright &y& Elsevier]

Abstract: The economic impact of blackbirds can be severe to rice producers in the United States. One approach to managing this damage is the application of bird-deterrent chemical to the crop. Previous pilot trials suggested that caffeine offered potential as a safe, economical bird repellent. In this study, cage feeding trials with female red-winged blackbirds and male brown-headed cowbirds confirmed that a treatment rate of 2500ppm caffeine on rice seed reduced consumption as much as 76%. Trials with mixed species blackbird flocks in a 0.2-ha flight pen resulted in just 4% loss of caffeine-treated rice compared to 43% loss of untreated rice. Field trials of a 10,000ppm caffeine treatment in Louisiana revealed >90% of caffeine-treated rice seed remained unconsumed on days 2 and 3 of the study whereas blackbirds consumed >80% of the untreated seed. As a rice seed treatment to deter blackbirds, caffeine appears to be effective, economical and environmentally safe, although additional aquatic toxicity testing is desirable. Improvements in formulation will be needed to make the compound practical for general agricultural spray applications and to extend the adherence of caffeine to rice seeds in field conditions. [Copyright &y& Elsevier]

Abstract: The efficacy of mating disruption of pink bollworm Pectinophora gossypiella (Saunders) was evaluated by monitoring its population with pheromone baited traps as well as by sampling flowers and bolls to record damage levels in cotton fields in 1988 and 1989, in central Greece. PB-rope dispensers were used at a rate of 1000 per hectare in the treated fields, each field covered an area of 10 and 15ha in the first and second year, respectively. These treated fields were compared with control fields in which 2–3 insecticide sprays were applied. The dispensers reduced pink bollworm catches in pheromone traps and reduced crop damage. The direction of cotton rows in relation to the prevailing wind had a significant effect on moth catches and needs to be taken into account when using dispensers. Mating disruption was effective in preventing damage when applied early season, but damage levels were not proportionally reduced in relation to the reduction of trap catches. Sufficient gossyplure for reducing moth catches in the traps was in pheromone dispensers even 90 days in the field. [Copyright &y& Elsevier]

During 2000–2001, small mammals, birds, and potential corn/soybean damage were studied at a low-tillage, non-irrigated agricultural research site in the Colorado Piedmont. A small mammal survey involved four trapping sessions and 18, 12-live-trap grids each. Within years, two grids each were placed at random, fixed locations in experimental corn, fallow, millet, pea, soybean, sunflower, and wheat plots at the site; two off-plot grids each were set at random, fixed locations <100 m from the north and south edge of these plots. In 2001, periodic bird observations were conducted, and damage to corn and soybean plants was assessed. Capture rates were low during all trap sessions (range 0.1%–3.3%,X¯=2.2%). Sixty-three small mammals were captured and 39 were recaptured. Captures included deer mouse (Peromyscus maniculatus), northern grasshopper mouse (Onychomys leucogaster), thirteen-lined ground squirrel (Spermophilus tridecemlineatus), and western harvest mouse (Reithrodontomys megalotis). Deer mice accounted for 56 of the initial captures (88.9%). In-crop captures (n=15) and recaptures (n=16) were most frequent in wheat plots. Bird counts were low and included horned lark (Eremophila alpestris), killdeer plover (Charadrius vociferus), lark bunting (Calamospiza melanocorys), mountain plover (Charadrius montanus), mourning dove (Zenaida macroura), and western meadowlark (Sturnella neglecta). No direct seed removal, sprout removal, or plant clipping by small mammals or birds was observed, but some clipping of soybean plants was attributed to deer (Odocoileus virginianus and O. hemionus) and jack rabbits (Lepus townsendii or L. californicus). Plant debris accumulation is viewed as a key factor determining small mammal abundance and potential damage in low-till agriculture. [Copyright &y& Elsevier]

Experiments between 1996 and 1997 at the Manga Research Station in the Sudan savanna zone of Ghana on the effects of millet variety and date of sowing on the incidence of diapause in Coniesta ignefusalis showed that only the late millet variety Zaa supported C. ignefusalis larval diapause. Early millet was not important in supporting dry season survival of the insect. Delayed planting tended to increase the incidence of diapause, resulting in significantly higher numbers of diapausing larvae in millet stalks at the end of the growing season. Grain yields also declined with delayed planting. Diapausing larvae were extracted from plants of different ages during mid-November each year, suggesting that age of the host plant may not be the main factor inducing diapause development in this insect. The practical implications of these findings are discussed. [Copyright &y& Elsevier]

Many avian species are considered agricultural pests and cause severe and costly damage to crops worldwide. Crop producers use several methods to reduce damage by birds, with frightening devices serving among the most popular approaches. Biologically salient frightening devices, such as broadcast of conspecific alarm calls or placing predator models in fields, are considered particularly effective because they can trigger antipredator behaviors that reduce foraging activities or abundances of target birds locally. However, it remains unclear which type of biologically salient frightening device is most effective and whether some work best against certain bird species or on certain types of crops. We reviewed the published scientific literature to fill in these knowledge gaps about using biologically salient frightening devices for crop protection against avian pests. We found 48 experiments evaluating the impact(s) of biologically salient frightening devices. However, only 28 experiments statistically tested their results from which to draw conclusions. We found that alarm call playbacks, eye-spot balloons, or automated flying vehicles (UAVs) reduced avian abundance in all experiments. All experiments using alarm call playbacks, eye-spot balloons, hawk-kites, or UAVs effectively reduced crop damage. However, only experiments on passerine birds and in row crops were well-represented in these studies. We discuss potential biases in the literature that may limit our understanding of how birds respond to biologically salient frightening devices and suggest future directions that researchers might take to fill knowledge gaps. • Frightening devices are commonly used to protect crops from avian pests. • We reviewed the scientific literature on frightening device experiments. • Most scientific experiments with frightening devices target passerines. • There are no scientific experiments targeting cranes, geese, and doves. • Orchards are poorly represented in experiments compared to row crops and vineyards. [ABSTRACT FROM AUTHOR]

Weeding is critical to eliminate non-native plants that compete with main crops and adversely affect their production quality and quantity. Numerous prototypes exist for inter-row weeding but very limited for intra-row weed eradication. This study developed a tractor drawn integrated inter- and intra-row weeding (IIIRW) system for field crops. Active rotary tines were used for intra-row weeding and passive tines for inter-row weeding. Optimum operational configurations were obtained with rigorous repeated soil bin experiments, and developed system was evaluated for three growing seasons (2017–19) in field grown maize (Zea mays L.) and pigeon pea (Cajanus cajan (L.) Millsp.) crops. Optimum ratios of intra-row tine rotary speed to forward speed (u/v) were in the ranges of 0.8–1.3 that lead to weed mortality of 88.4 % (Buried: 8.5 %, Uprooted: 79.9 %), negligible intact weeds, and plant damage (P d) within 6 %. Sole inter-row weeding operation resulted up to 78.1 % of weed mortality (Buried: 18.1 %, Uprooted: 60.0 %) and negligible P d. Overall weed mortality with the IIIRW system was 92.8 % (Buried: 9.5 %, Uprooted: 83.3 %) in maize and 84.1 % (Buried: 7.6 %, Uprooted: 76.5 %) in pigeon pea crops. Results suggest suitability of the IIIRW system for a range of similar crops for field capacity in ranges of 0.22–0.26 ha/h at recommended operating speeds within 0.50–0.56 m/s. The IIIRW system requires a single prime mover and could be potentially economical and efficient technology for field weeding operations. [Display omitted] • Developed and field evaluated was a hydromechanical inter- and intra-row weeder. • Three-year evaluations in field grown maize and pigeon pea crops. • Mean weeding efficiency up to 88% was attained. • Crop plant damages did not exceed 6%. • High field capacity and low operational costs were evident. [ABSTRACT FROM AUTHOR]

Wild pigs (Sus scrofa) are a destructive invasive species that cause extensive damage to agriculture throughout many regions of the world. In particular wild pigs damage corn more than any other crop, and most of that damage occurs immediately after planting when wild pigs excavate and consume planted seeds. We evaluated whether anthraquinone (AQ), a repellent, could be useful for protecting seed corn from consumption by wild pigs. Specifically, we conducted cafeteria-style tests at 16 bait sites for 6 nights using concentrations of: untreated, 0.5, 1.5, and 3.0% AQ by weight sprayed on whole-kernel corn in AL and TX, USA. We found that repellency for wild pigs was dependent on the AQ concentration, with the greatest repellencies of 95% (AL) and 59% (TX) observed using ~3% AQ. We also found that repellency decreased as the abundance of wild pigs increased at the bait sites. Raccoons (Procyon lotor) did not appear to be repelled by the AQ-coated corn, but white-tailed deer (Odocoileus virginianus) and mule deer (O. hemionus) were. Overall, our results show promise for the development of a repellent for treating seeds to protect them from wild pigs. We recommend the next steps of testing of the 3% concentration of AQ on corn seeds that are planted underground to optimize the best potential protection against damage from wild pigs. • A 3% anthraquinone spray treatment on corn showed promise for reducing consumption by wild pigs. • Repellencies of 95% and 59% on treated corn were observed in Alabama, and Texas, respectively. • Repellency declined as larger groups of wild pigs fed on the treated corn. [ABSTRACT FROM AUTHOR]

The global expansion of wild pigs over the last few decades has resulted in an increase in extent and distribution of damages to crops, placing a growing strain on agricultural producers and land managers. Despite the extent of wild pig damage to agriculture, there is little data regarding timing and spatial variability of damage to corn (Zea mays Linnaeus) and we found no data regarding the effect of these factors on peanuts (Arachis hypogaea Linnaeus). Our objective was to determine the timing and extent of wild pig damage to corn and peanut fields, as well as the extent to which local habitat attributes are useful predictors of damage to these crops. During 2017–2018 we performed ground-based surveys throughout the growing season for 29 corn and 41 peanut fields in South Carolina, USA to determine the most important growth stages for wild pig depredation in both crops. Damage to corn peaked shortly after planting during the seedling stage, fell to nearly zero during V4–V6 stages, and resumed during the silk and mature stages. Peanut damage was almost exclusively limited to the seedling stage. Landscape models for both crops identified the extent of forested and wetland areas surrounding crop fields as the most important attributes positively associated with wild pig damage, while the amount of adjacent agricultural area and paved roads were associated negatively. The number of wild pigs identified by remote cameras also was an important indicator of the extent of damage to peanut fields. Results suggest management efforts to limit crop depredation by wild pigs should be targeted shortly prior to planting. Further, because damage was positively associated with the availability of wetland and forest habitats, our results suggest agricultural damage by wild pigs may be most severe near areas of preferred native habitats. • Wild pig damage to corn and peanuts varied significantly among plant growth stages. • Majority of wild pig damage occurred at the emergence stage for both crops. • Greater area of forests and wetlands adjacent to fields was associated with more damage. • Adjacent agricultural area and presence of paved roads were associated with lower damage. [ABSTRACT FROM AUTHOR]

We report the results of a survey on invasive wild pig (Sus scrofa L.) damage and control in 12 US states (Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, and Texas). The crops chosen for this study represent the "second tier" in terms of economic importance after the six crops that were the subject of Anderson et al. (2016). The survey was distributed by the USDA National Agricultural Statistical Service (NASS) in the summer of 2019 to a sample of producers in each of the states (except California) of the following six crops: hay, pecans (Carya illinoinensis (Wangenh.) K.Koch), melons (cantaloupe (Cucumis melo L. var. cantalupensis), honeydew (Cucumis melo L. (Inodorus Group)), and watermelon (Citrullus Schrad.), sugarcane (Saccharum officinarum L.), sweet potatoes (Ipomoea batatas (L.) Lam.), and cotton (Gossypium L.). In California, where there the crops of economic importance differed from the other states in the study, damages were calculated for producers of hay, almonds (Prunus dulcis (Mill.) D.A. Webb), grapes (Vitis vinifera L.), sod, carrots (Daucus L.), lettuce (Lactuca L.), and strawberries (Fragaria L.). In total, 7438 respondents completed the questionnaire. Findings indicate that damage can be substantial. The highest yield loss estimates occurred for hay in Texas. Control efforts were common, but no control method was rated by the majority of producers as very effective. Extrapolating crop damage estimates to the state-level in 12 states with reportable damage yielded an estimated crop loss of $272 million/yr. Though large, this number likely represents only a small fraction of the total damage by wild pigs in these states because it only includes crop damage to six crops. We hope findings from this survey will help guide control efforts and research, as well as serve as a benchmark against which the effectiveness of future control efforts can be measured. • Estimated crop loss due to feral swine of $272 million for the surveyed set of crops in 12 states. • Highest loss ratio was reported for pecans (Texas 13.46% and Florida 12.56%). • Loss ratio for cotton was lower, ranging from 0% in Missouri to 3.1% in Florida. • No control method was rated as extremely effective by the majority of the respondents. [ABSTRACT FROM AUTHOR]

Wildlife damage to agriculture causes significant economic losses worldwide. The amount of compensation payment is often determined by field damage evaluation, but there is little statistically sound information on the applied sampling and calculation methods of such losses. In this study, we tested the accuracy and bias of V-Track Method (VTM), W-Track Method (WTM), Double Diagonal Method (DDM), and Grid Arrangement Method (GAM) in GIS environment. Besides the accuracies and biases, the effects of the rate and spatial distribution of the damage (and the interaction of these factors) on the sampling results were examined. Simulations were conducted with four different spatial damage patterns [random, aggregated in patches (DAinP), furthermore aggregated in one and two field edges (DAinE-1, DAinE-2) to simulate the effect of an adjacent forest on the damage caused by big game species] and three levels of damage (10%, 20%, 30%). According to our results, the GAM provided the majority (58.3%) of best results for each statistical parameter (28/48), while gave the worst result three times. The WTM resulted in the highest number (17/48) of worst values and 8/48 best results. The DDM gave 14/48 poorest values, while provided 7/48 best results. The VTM resulted in 14/48 worst values, while provided the best result five times. The rate and spatial distribution of the damage, as well as the interaction of these factors, had a significant effect on the Percentage Relative Bias of the VTM, WTM and DDM estimations, while the GAM sampling was significantly affected only by the damage distribution. • GIS simulation is suitable for testing the agricultural wildlife damage samplings. • We found difference between the results of Grid Arrangement and quadrats. • GAM provided the majority of best results in case of each statistical parameter. • Unlike the other methods, GAM was affected only by the spatial damage distribution. • Due to their lower labour-intensity, quadrats are still relevant for practical use. [ABSTRACT FROM AUTHOR]

Wild pigs (Sus scrofa) cause extensive damage to agricultural crops, resulting in lost production and income. A major challenge associated with assessing damage to crops is locating and quantifying damaged areas within agricultural fields. We evaluated a novel method using multispectral high-resolution aerial imagery, collected from sensors mounted on unmanned aircraft systems (UAS), and feature extraction techniques to detect and map areas of corn fields damaged by wild pigs in southern Missouri, USA. Damaged areas were extracted from ortho-mosaics using visible and near-infrared band combinations, an object-based classification approach, and hierarchical learning cycles. To validate estimates we also collected ground reference data immediately following flights. Overall accuracy of damage estimates to corn fields were similar among band combinations evaluated, ranging from 74% to 98% when using visible and near-infrared information, compared to 72%–94% with visible information alone. By including near-infrared with visible information, though, we found higher average kappa values (0.76) than with visible information (0.60) alone. We demonstrated that UAS are an appropriate platform for collecting high-resolution multispectral imagery of corn fields and that object-oriented classifiers can be effectively used to delineate areas damaged by wild pigs. The proposed approach outlines a new monitoring technique that can efficiently estimate damage to entire corn fields caused by wild pigs and also has potential to be applied to other crop types. • UAS and machine learning was used to detect and quantify damage to crops caused by wild pigs. • Multispectral imagery yielded more accurate damage maps than using visible imagery alone. • The UAS platform provided a unique 'bird's-eye' view for all fields for damage mapping. [ABSTRACT FROM AUTHOR]