Integrating Beetle Habitat into Pacific Northwest Farming Systems

Integrating Beetle Habitat into Pacific Northwest Farming Systems

Summary

The overall goal of this two year project (with a granted one year no-cost extension) is to provide guidelines for implementing generalist predator habitat (beetle banks) on farms in the Pacific Northwest. Improving habitat for generalist predators such as ground beetles is a promising biological control strategy that offers an alternative to pesticide use. We have made significant progress towards this goal over the first two years of the project. We conducted extensive field work that included developing detailed GIS-based habitat maps of each of our cooperating farms, conducting monthly spatially explicit censuses of beetle activity and documenting prey consumption patterns, both in the field and under controlled laboratory conditions. We used these two years of data to develop and refine habitat-based models that describe how the occurrence and diversity of beetle species varies seasonally and across habitat types on our study farms. The preliminary results that we reported in our previous report have been strengthened and enhanced with our second field season of data. These findings indicate that the habitat composition and diversity on a farm strongly influences the types and abundance of beetles found three. In addition, only a subset of beetles commonly found on a farm is active within production fields, and this activity varies seasonally.

As in the previous year of our study, we did this work in collaboration with our cooperating farmers through direct one-on-one interaction over the course of the field season and through a combined winter project meeting and short course attended by 10 farmers. At the meeting we discussed project goals, elicited feedback on results and planned broader outreach activities. We communicated results from the project and provided more comprehensive information about management of on-farm conservation habitat during a summer farm walk and short course. The short course was attended by 15 farmers and non-profit personnel. The short course served as a venue for farmer-to-farmer exchanges that promoted the regional development of successful on-farm habitat enhancement practices.

In the extension year of the project, we will incorporate the results from the eastern Washington component of our program with our Oregon results. We will integrate these research results, along with the feedback that we got from farmers during our outreach events, to revise, enhance and develop the outreach and management tools described in our proposal: a worksheet to help farmers evaluate and manage effective beetle habitat on their farm, extension documents describing beetle biology and the beneficial roles they play on farms, and a website to publicize project information and to foster farmer interaction. We will also publish our research findings in peer-reviewed scientific journals.

Objectives/Performance Targets

Research

1. Develop a habitat-based model that predicts the occurrence of beetle species at the farm-scale in Pacific Northwest agricultural landscapes.
2. Determine how the farm-scale arrangement of habitat types. influences beetle activity patterns within fields.
3. Determine how activity within fields influences prey consumption beetle.

Outreach

4. Provide specific recommendations based on farmer generated research questions.
5. Facilitate regional cooperation among farmers and researchers developing conservation biological control.

Accomplishments/Milestones

We have made significant progress towards achieving the project objectives and performance targets described in the proposal.

Objective 1. Develop a habitat-based model that predicts the occurrence of beetle species at the farm scale in Pacific Northwest agricultural landscapes.

Future tasks (as planned in our previous annual report)

We are in the process of repeating our winter and summer sampling regime to provide an additional year of data. These data will allow us to refine our habitat models and to evaluate the degree of year-to-year variability in beetle assemblages on farms.

As we reported in our previous annual report, we produced detailed GIS-based vegetation maps for each of our five cooperator farms using high resolution aerial photographs and ground sampling, and then used extensive field sampling to develop models that are able to predict the likely composition of the beetle assemblage on a farm based on the types of habitats found there. In the second year of the study we refined our models based on a second full field season of data. The general patterns that we saw were consistent with our first year observations, but our model resolution and our ability to discern differences in activity patterns and habitat use among beetle species has been greatly improved.

For instance, we now have a fairly robust description of the seasonal changes in both overall activity and community composition of ground beetles within the agricultural systems of western Oregon (Figures 1-2).

Future tasks during project extension

We are in the process of further analyzing these data statistically to increase the robustness of our conclusions and recommendations. We will also incorporate these data into published extension and peer reviewed scientific publications. In addition, we will do similar analyses on the eastern Washington data that we recently acquired and will acquire during the summer 2012 field season.

Objective 2. Determine how the farm-scale arrangement of habitat types influences beetle activity patterns within fields.

Future tasks (as planned in our previous annual report)

Our next step in this analysis is to use SADIE analysis to develop a more detailed spatially and temporally explicit model of beetle activity. Our current species profiles give us a nice overview representation of when and where particular beetle species are likely to be found in a farm landscape. Our planned SADIE analysis will allow us to develop explicit maps of likely beetle activity over a season. This analysis will be made robust with a second year of data collection, which is why we have postponed doing this work until we have two full years of data.

As we reported earlier, we used our extensive spatially explicit sampling of beetle activity to develop a comprehensive picture of seasonal beetle activity across the complex landscapes of our cooperating farms. Our second year allowed us to construct very detailed species specific profiles of beetle activity (Fig. 3). The most pertinent findings from these data are that a diverse set of small beetle species make up the bulk of the beetle activity on farms early in the season (e.g. Amara littoralis, Omus sp). These species require undisturbed perennial grass habitat to maintain overwintering populations on farms. In contrast, species such as Pterostichus algidus that dominate activity later in the season display far less specific overwintering habitat requirements. This suggests that habitat improvements will have the greatest influence on early season beetle activity (and the associated pest suppression they may provide).

Future tasks during project extension

Now that we have a full two years of data, we have started the SADIE analysis described above. Also, as with objective 1, we will incorporate these data into published extension and peer reviewed scientific publications and do similar analyses on the eastern Washington data that we recently acquired during the summer 2012 field season.

Objective 3. Determine how activity within fields influences prey consumption beetles.

Future tasks (as planned in our previous annual report)

We have two main tasks to complete. The first is to incorporate our field measures of prey consumption rates into our analysis. Along the same spatially explicit sampling grid that we used to measure beetle activity, we also assessed prey consumption. We plan to incorporate these data into our SADIE analysis to test whether different habitat types have different overall levels of prey consumption, and whether prey consumption is spatially correlated with beetle activity. We had some technical difficulties in collecting the prey card data this past season that we hope to correct in this upcoming field season.

As reported earlier, we tested for differences in relative prey consumption on farms by deploying sentinel prey cards. We also exposed field captured individuals to different prey items in experimental feeding arenas to test how their voracity and feeding preferences vary between species and seasonally. We have found that species differ considerably in their feeding behavior and relative preferences (Fig. 3-4). Our second year of data have confirmed our initial observations, and it allowed us to make more robust statistical inferences about prey choice.

Future tasks during project extension

We have waited to perform the SADIE analyses described above until we had data from are second full field season. We made some improvements to or prey card design, and we think this has improved the quality of the data. We plan to complete these analyses, as well as perform similar analyses on the data from the Washington field site.

Objective 4. Provide specific recommendations based on farmer generated research questions.

Future tasks (as planned in our previous annual report)

We had to cancel our planned summer 2010 farm walk at Persephone Farm due to an overwhelmingly too busy schedule for the farmers. Summer 2010 was a very trying summer for most Willamette Valley farmers, as the weather was very cold and wet long into July, making getting into the field difficult and delaying most field production work. An unsuccessful attempt was made to set up a substitute walk in early fall with other growers, but similar problems and short notice worked against us. We expect the 2011 Oregon field class summer component to go more smoothly.

We are combining the 2011 winter project meeting and winter field class for the participating farmers’ convenience and to enable us to begin working with them and other farmers as well on the habitat evaluation worksheets. We anticipate the worksheets will include farmer originated ways to map existing and future on-farm habitat. At this meeting we will present the results and analysis from our previous season’s field work.

We conducted the planned outreach events described above as follows:

1. A combined winter project meeting and field class held 2/25/2011 in Corvallis, OR. This meeting included one additional farmer not directly collaborating on our project who was interested in hearing our results and getting recommendations for installing habitat. Similar to our previous project meetings, we shared with participating farmers the results of our field work, planned upcoming work and analyses and planned the location and format of our summer field course.

3. A farm walk and short course held 9/1/2011 on Gathering Together Farm, Philomath OR. The course was titled Assessing Beneficial Insect Habitat on Your Farm: A Predacious Ground Beetle Example and attracted 15 participants that included farmers, farm personnel and government agency representatives. The course used our established model of active learning and collaborative participation described in the proposal and the previous annual report (See appendix 1 for the agenda of the course). Part of the course involved a habitat mapping exercise to train farmers in identifying existing beneficial predator habitat, as well as gaps where improvements in habitat could be useful. During this exercise, we trialed a draft habitat assessment worksheet (see Appendix II for an example worksheet from the summer short course); development of this worksheet is one of the outreach goals of our project. We also elicited feedback from participants on this worksheet, as well as on other ways conveying practical information to farmers. The habitat mapping process (and overall class) was informed by findings developed in the research component of our project.

Future tasks during project extension

We are in the process of analyzing the data from participant surveys designed to evaluate the effectiveness of our outreach events as well as the impact of our project on farmer knowledge and actions over time. We are also using feedback from the habitat mapping exercise to revise our habitat mapping worksheet.

Objective 5. Facilitate regional cooperation among farmers and researchers developing conservation biological control.

The farmer meetings and short course described above also served as venues for farmer-to-farmer exchanges that promoted the regional development of successful on-farm habitat enhancement practices.

All the participating farmers in our project have led tours and given presentations to a broad audience of farmers, students, agricultural professionals and consumers since our last annual report. Many of them participated (and hosted) the farmer meetings and short course described above. At these events they were critical parts of the program, and they shared their immense practical experience in creating and marinating beneficial predator habitat with other farmers.

Several of the participants at the summer short course expressed interest in being part of an OREI project proposal that we were then developing. All participants also provided contact information and expressed an interest in being involved in future events.

Future tasks during project extension

We are developing an extension publication tentatively titled Integrating Habitat for Predatory Ground Beetles into Your Farm that will be submitted for peer review by late spring. We are also revising a beetle identification guide and incorporating our research findings into our existing websites.

• Figure 3
• Figure 4
• Figure 2
• Appendix II
• Figure 1
• Appendix I

Impacts and Contributions/Outcomes

In the second year of this project, we will incorporate this new information into specific tools that will assist farmers in planning and implementing effective beetle habitat on their farm.

We will give our knowledge assessment survey to farmers a second time to assess the degree to which our project empowers farmers to actively manage habitat on their farms.

We have continued to make significant progress towards meeting our short-term outcomes. Our short courses and project meetings have introduced regional farmers to the ecology, biology and potential ecological services that predacious ground beetles provide farms. As we planned, in the second year we also used these meetings to provide farmers with practical recommendations based on the findings from our two seasons of research. The events also trained farmers to evaluate their farms in terms of beetle habitat and to institute practices that can enhance this habitat on their own farms.

We will give our knowledge assessment survey (Appendix III) to our collaborating farmers a second time at our winter project meeting. We also gave a course evaluation survey to participants of the summer short course (Appendix IV) to assess the degree to which or project activities are empowering farmers to actively manage habitat on their farms. We are still in the processes of combining the data from these surveys with previous years, but preliminary analysis indicates that both the farmer-to-farmer exchanges and the short course activities have increased knowledge about the value of beneficial predator habitat and have provided practical guides for integrating that habitat in typical farming systems in the Pacific Northwest.

• Appendix III

Collaborators: