Managing for Multiple Objectives
Agriculture faces a set of major interrelated challenges in the 21st century: it must achieve global food security, meet high quality and safety demands, reverse degradation of ecological life-support systems, and respond to an ongoing biodiversity crisis. While agricultural systems can be managed to yield diverse benefits, only recently have we begun to acknowledge and identify the multiple ecological tradeoffs associated with alternative management decisions. These tradeoffs suggest that optimal conservation strategies in agricultural lands may differ radically depending on the objective. For example, preventing agricultural expansion with nature reserves may stave off extinctions through protecting severely threatened species, while incentivizing farmers to plant hedgerows may benefit people through bolstering pest-eating or pollinating species. Win-win interventions that satisfy multiple objectives are alluring, but can also be elusive.
To achieve better outcomes, we developed and implemented a practical typology of nature conservation framed around six common conservation objectives (Karp et al. 2015 PNAS a,b). Using an intensively studied bird community in southern Costa Rica as a model system, we applied the typology in the context of biodiversity’s most pervasive threat: habitat conversion. Despite several observed tradeoffs, our approach identified strategies for achieving multiple conservation objectives simultaneously; for example, by maintaining forest patches within agricultural systems.
In California, concern that wildlife spread foodborne diseases has created strong pressure on growers to prevent wildlife from accessing their farms (See video below). Despite increasing recognition that agro-ecosystems should be managed to yield diverse, multifunctional benefits, growers are now forced to engage in practices that narrowly address perceived food-safety risks. The socio-ecological consequences may be severe (Karp et al. 2015 Bioscience). For example, our work has demonstrated that removing non-crop habitat to prevent wildlife from entering farm fields reduces pest-control services to agriculture without mitigating food-safety risks (Karp et al. 2015 PNAS, Karp et al. 2016 Journal of Applied Ecology).
Looking forward, we seek to develop better strategies for co-managing food safety, biodiversity, ecosystem service, and yield outcomes. For example, we will to quantify services (e.g., pest regulation) and disservices (e.g., disease propagation and crop losses) associated with birds that frequent strawberry fields and then test how alternative practices affect both beneficial and problematic species. Through interdisciplinary collaborations and by combining ecological, economic, sociological, and psychological approaches as well as by disseminating findings in workshops and with decision-support tools, our intent is to change practices and potentially reframe grower attitudes towards birds.
Video: The Nature Conservancy’s media team produced a video showcasing our research into the cascading socio-ecological consequences of food-safety management in California’s Central Coast.
- Karp, D.S., R. Moses, S. Gennet, M. Jones, S. Joseph, L.K. M’Gonigle, L.C. Ponisio, W.E. Snyder, and C. Kremen. (2016) Farming practices for food safety threaten pest-control services to fresh produce. Journal of Applied Ecology 53:1402-1412.
- Karp, D.S.*, P. Baur*, E.R. Atwill, K. DeMaster, S. Gennet, A. Iles, J. Nelson, A. Sciligo, and C. Kremen (2015) Unintended ecological and social impacts of food safety regulations in the California Central Coast. BioScience 65: 1173-1183.
- Karp, D.S., C.D. Mendenhall, E. Callaway, L. Frishkoff, P.M. Kareiva, P.R. Ehrlich and G.C. Daily (2015) Confronting and resolving competing values behind conservation objectives. PNAS 112: 11132-11137.
- Karp, D.S., C.D. Mendenhall, E. Callaway, L. Frishkoff, P.M. Kareiva, P.R. Ehrlich and G.C. Daily (2015) Reply to Kirchkoff: Homogenous and mutually exclusive conservation typologies are neither possible nor desirable. PNAS 112: e5906.
- Karp, D.S., S. Gennet, C. Kilonzo, M. Partyka, N. Chaumont, E.R. Atwill, and C. Kremen. (2015) Co-managing agriculture for nature conservation and food safety. PNAS 112: 11126-11131.
- Garbach, K., J.C. Milder, M. Montenegro, D.S. Karp, and F. DeClerke. (2014) Ecosystem Services in Agricultural Lands. In: The Encyclopedia of Agriculture.