Literature Review and Final Project Proposal

Transcription

1 Literature Review and Final Project Proposal Name Redacted GSP 370 Introduction In Napa Valley, California, a main issue faced by farmers is rodent crop damage. Bird and rodent pests cost $ million in damage to California crops annually (Baldwin, Salmon, Schmidt, & Timm, 2014). In an industry valued at $3.7 billion with a $50 billion impact on the American economy (Stonebridge, 2012), wine producers need a method to control rodent damage. Barn owls (Tyto alba) are valuable biological control agents, which vineyard owners attract to their properties by installing nest boxes (Meyrom et al., 2009). By attracting barn owls to breed on their property, wine producers hope to reduce the population of rodent pests and save on costs from other methods of pest control. The alternatives to barn owl programs are both costly and potentially unsafe. Vineyard managers often turn to lethal trapping and the use of chemical rodenticides, but these are problematic because they can be labor intensive or lead to risks of secondary poisoning (Baldwin et al., 2015; Baldwin, Meinerz, & Witmer, 2017; Marsh, 1992). The need to control rodent pests has led to an interest in integrated pest management using biological control agents, primarily barn owls (Tyto alba) (Labuschagne, Swanepoel, Taylor, Belmain, & Keith, 2016). By installing nest boxes around vineyards, farmers can attract barn owls, which may be able to act as a natural predator and control populations of pocket gophers (Thomomys bottae) and voles (Mictrotus spp.) (Browning, Cleckler, & Johnson, 2017; Kan et al., 2013; Meyrom et al., 2009; Paz et al., 2012). Barn owls are an attractive pest control option, as they have been found to be profitable for controlling rodents in other crop types, such as alfalfa in Israel (Kan et al., 2013). While rodents are an important concern for wine producers, changing climate and land use are leading to other crises. Starting on October 8 th, 2017, wildfires throughout northern California s wine country destroyed thousands of homes, burned through natural habitat and scorched the grounds of vineyards. Within one week, the fires burned over 150,000 acres in Napa and Sonoma counties (Fuller, Grady, & Pérez-Peña, 2017). Given the economic importance of vineyards in the region and the loss of a significant portion of the landscape, it is important to understand how the wildfires changed the surrounding habitat and how that will affect the ecology of the area. The landscape in Napa Valley has been changing rapidly and wildfires are expediting some of these changes. Between 1990 and 2000, wine grape acreage in California was approximately doubled (Merenlender, 2000). In Sonoma County, a model predicting the maximum amount of land that could be converted to vineyards

2 showed a significant reduction in continuous patches of tree cover (Heaton & Merenlender, 2000). Furthermore, climate change is expected to change which areas are suitable for vineyards, leading to vineyard expansion that will displace wildlife and natural habitat (Hannah et al., 2013). This expansion into natural habitats has implications for biodiversity, pest control, and other ecosystem services. Land use, climate, and the economic success of the vineyard industry are all important factors, which are complicated more by the addition of wildfires. Wildfires are likely to increase in the western United States due to changing climate and the response of wildlife and birds to fires is largely unknown (Fontaine & Kennedy, 2012; Westerling, 2006). There is an urgent need to understand how wildlife responds to wildfires, as the likelihood of devastating fires is likely to increase in the future. Where human communities and natural habitats intersect, and where wildlife can provide an ecosystem service like pest control, the need to quantify the effects of fire is even more valuable. In Napa Valley, few vineyards were actually burned and the fire primarily burned through communities, grassland, and wooded areas (Lapsley & Sumner, 2017). However, ecosystem services depend on the landscape as a whole, and not just on a single habitat type. Landscape composition has become a major focus for research related to ecosystem services in agroecosystems. Simplified agricultural landscapes often have negative effects on biological control agents (Perović, Gurr, Raman, & Nicol, 2010), but depending on the system, an increase in landscape complexity can have no, or even negative effects, on pest control (Tscharntke et al., 2016). More research is needed to understand how changes to landscape composition in Napa Valley affect the delivery of ecosystem services. The goal of this project will be to analyze the change in barn owl habitat in Napa Valley resulting from the Atlas and Nuns fires that burned over 100,000 acres in nest boxes in vineyards were monitored for barn owl occupancy in 2015 and 150 were revisited in 2016 and 2017 (Wendt & Johnson, 2017). It is unknown how the birds will respond to the change in habitat produced by the fires, but the first step is to visualize and quantify how much of the habitat surrounding each nest box was affected. Specifically, the objective of this project will be to create a map that makes it possible to geospatially visualize the effects of the fire and quantify the different habitat types that were burned. The results of this project will be invaluable for enhancing my master s thesis. With a detailed map of habitat types around each box and the effect of fire, I can make more informed decisions about which nest boxes to study in depth. I will be using GPS tracking of owls in a gradient of burned and unburned habitat to understand how their nesting and hunting behavior has changed in response to the fires. With a map that clearly specifies how the fires changed wildlife habitat, it will be possible to answer a variety of important questions about barn owl response to the Napa Valley fires.

3 Methods To visualize the effects of the fire on the habitat surrounding each nest box, ArcMap will be used to generate a map of the study area. All GIS data to be included in analysis are recorded in Table 1. Various land cover types characterize Napa Valley, including natural and human inhabited regions. Land cover types have already been classified into water, urban, vineyard, grassland, oak scrub, mixed forest, and riparian using CropScape data and GPS points have been taken for all next boxes (Wendt & Johnson, 2017). These will be used as the initial data for analysis of the habitat before the 2017 fires. A second map will then be generated using fire perimeters of the Atlas and Nuns fires of 2017 (CalFire, 2017). The fire perimeters will be clipped using the land cover classification layer from Wendt & Johnson (2017). All of the 297 next boxes are located within the boundaries of the land cover layer. Each nest box will then be buffered with a 2.86 km radius from the location of the box. Castañeda (unpublished) found through GPS tracking that 2.86 km is the mean maximum distance moved by an individual barn owl from its nest box during the breeding season. This radius will allow finer scale analysis of the habitat surrounding each nest box. Once a layer has been created of the radius surrounding each nest box, the amount of area affected by the fires can be visualized. The map will be accompanied by table of descriptive statistics, including percent of each habitat type that was burned in the entire study system and in each box radius. I will calculate the amount of each habitat type around each nest box before the fire and the amount of each habitat affected by the fire around each nest box. This will be done either in ArcMap or in a programming language such as Python. The final map will also have symbology to distinguish between next boxes that have historically been occupied by breeding barn owls and those that have not. GIS Data Source Land cover classification Wendt & Johnson, 2017 Nest box locations and occupancy data Wendt & Johnson, 2017 Fire perimeters Napa County boundary California State boundary Table 1 GIS data and sources for use in ArcMap Project Schedule The following Gantt Chart (Figure 1) describes the schedule for major tasks for the final project. In order of completion, activities include, acquiring data from online, submitting literature review, creating maps, calculating and recording statistics, writing paper, revising paper, and submitting paper. These will all be accomplished by the final deadline of December 8 th.

4 11/13/17 11/20/17 11/27/17 12/04/17 12/11/17 Acquire Data from Online Submit Literature Review Create Maps Calculate and Record Statistics Write Paper Revise Paper Submit Paper Figure 1 Gantt chart describing timeline of major activities for final project References Baldwin, R. A., Chapman, A., Kofron, C. P., Meinerz, R., Orloff, S. B., & Quinn, N. (2015). Refinement of a trapping method increases its utility for pocket gopher management. Crop Protection, 77, Baldwin, R. A., Meinerz, R., & Witmer, G. W. (2017). Novel and current rodenticides for pocket gopher Thomomys spp. management in vineyards: what works? Pest Management Science, 73(1), Baldwin, R. A., Salmon, T. P., Schmidt, R. H., & Timm, R. M. (2014). Perceived damage and areas of needed research for wildlife pests of California agriculture. Integrative Zoology, 9, Browning, M., Cleckler, J., & Johnson, M. (2017). Prey Consumption by a Large Aggregation of Barn Owls in an Agricultural Setting. Proc. 27th Vertebr. Pest Conf., CalFire. (2017). Incident Information. Retrieved from Fontaine, J. B., & Kennedy, P. L. (2012). Meta-analysis of avian and small-mammal response to fire severity and fire surrogate treatments in U.S. fire-prone forests. Ecological Applications, 22(5), Fuller, B. T., Grady, D., & Pérez-Peña, R. (2017). California Fires Leave 31 Dead, a Vast Landscape Charred, and a Sky Full of Soot. The New York Times, pp Hannah, L., Roehrdanz, P. R., Ikegami, M., Shepard, A. V., Shaw, M. R., Tabor, G., Hijmans, R. J. (2013). Climate change, wine, and conservation. Proceedings of the National Academy of Sciences, 110(17), Heaton, E., & Merenlender, A. M. (2000). Modeling vineyard expansion, potential habitat fragmentation. California Agriculture, 54(3), Kan, I., Motro, Y., Horvitz, N., Kimhi, A., Leshem, Y., Yom-Tov, Y., & Nathan, R. (2013). Agricultural Rodent Control Using Barn Owls: Is It Profitable? American Journal of Agricultural Economics, Labuschagne, L., Swanepoel, L. H., Taylor, P. J., Belmain, S. R., & Keith, M. (2016). Are avian predators effective biological control agents for rodent pest management

5 in agricultural systems? Biological Control, 101, Lapsley, J. T., & Sumner, D. A. (2017). Napa and Sonoma County Fires and the Wine Industry. Marsh, R. (1992). Reflections On Current Pocket Gopher Control in California. In Proceedings of the Fifteenth Vertebrate Pest Conference 1992 (pp ). Retrieved from c15 Merenlender, A. M. (2000). Mapping vineyard expansion provides information on agriculture and the environment. California Agriculture, 53(3), Meyrom, K., Motro, Y., Leshem, Y., Aviel, S., Izhaki, I., Argyle, F., & Charter, M. (2009). Next-box use by Barn Owl Tyto alba in a Biological Pest Control Program in the Beit She an Valley, Israel. Ardea, 97(4), Paz, A., Jareño, D., Arroyo, L., Viñuela, J., Arroyo, B., Mougeot, F., Fargallo, J. A. (2012). Avian predators as a biological control system of common vole (Microtus arvalis) populations in north-western Spain: Experimental set-up and preliminary results. Pest Management Science, 69(3), Perović, D. J., Gurr, G. M., Raman, A., & Nicol, H. I. (2010). Effect of landscape composition and arrangement on biological control agents in a simplified agricultural system: A cost-distance approach. Biological Control, 52, Stonebridge. (2012). The Economic Impact of Napa County s Wine and Grapes. Tscharntke, T., Karp, D. S., Chaplin-Kramer, R., Bátary, P., DeClerck, F., Gratton, C., Zhang, W. (2016). When natural habitat fails to enhance biological pest control - Five hypotheses. Biological Conservation, 204, Wendt, C. A., & Johnson, M. D. (2017). Multi-scale analysis of barn owl nest box selection on Napa Valley vineyards. Agriculture, Ecosystems, and Environment, 247, Westerling, A. L. (2006). Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity. Science, 313(5789),