Spatial Ecology

Understanding the relationships of species in space and with their environment is fundamental to being able to manage landscapes effectively, and to design them.  Spatial ecology offers tools and approaches to understand these dynamics. We have applied new techniques to monitoring and assessing the health of rare butterfly populations, used spatial modeling to predict the distribution of invasive species, and assessed the performance of inductive vs. deductive modeling approaches in defining species ranges.

Current Projects

Habitat modeling to define the historic range of Kern Primrose Sphinx Moth

Coyote and feral cat co-occurance in an urban wildland


Longcore, T., L. Almaleh,* B. Chetty,* K. Francis,* R. Freidin,* C.-S. Huang,* B Pickett,* D. Schreck,* B. Scruggs,* E. Shulman,* A. Swauger,* A. Tashnek,* M. Wright,* and E. E. Boydston. 2018. Wildlife corridor use and environmental impact assessment: a southern California case study. Cities and the Environment11(1):art4.

Dupuis, J.R., J.C. Oliver, B.M.T. Brunet, T. Longcore, J.J. Johnson, and F.A.H. Sperling. 2018. Genomic data indicate ubiquitous evolutionary distinctiveness among populations of California metalmark butterflies. Conservation Genetics.

Paudel, S., J. C. Benavides, B. MacDonald, T. Longcore, G. W. T. Wilson, and S. R. Loss. 2017. Determinants of native and non-native plant community structure on an oceanic island. Ecosphere 8(9):e01927.

Paudel, S., G.W.T. Wilson, B. MacDonald, T. Longcore, and S. R. Loss. 2016. Predicting spatial extent of invasive earthworms on an oceanic island. Diversity and Distributions 22(10):1013–1023.

Paudel, S., T. Longcore, B. MacDonald, M. McCormick, K. Szlavecz, G. Wilson, and S. R. Loss. 2016. Belowground interactions with aboveground consequences: invasive earthworms and arbuscular mycorrhizal fungi. Ecology 97(3): 605–614.

MacDonald, B., T. Longcore, and S. Dark. 2010. Habitat mapping for western snowy plover in central California. The Urban Wildlands Group, Los Angeles. 129 pp.

Longcore, T., C. S. Lam, P. Kobernus, E. Polk, and J. P. Wilson. 2010. Extracting useful data from imperfect monitoring schemes: endangered butterflies at San Bruno Mountain, San Mateo County, California (1982–2000) and implications for habitat management. Journal of Insect Conservation 14(4):335-346.

Longcore, T., and C. Rich. 2008. Invertebrate conservation at the gates of hell. Wings: Essays on Invertebrate Conservation.

Jump, P., T. Longcore, and C. Rich. 2006. Ecology and distribution of a newly discovered population of the federally threatened Euproserpinus euterpe (Sphingidae). Journal of the Lepidopterists’ Society 60(1):41–50.

Longcore, T., R. Mattoni, and A. Mattoni. 2005. Salvage of pupae as a mitigation measure for impacts to endangered butterfly habitat. Journal of the Lepidopterists’ Society 59(2):116–117.

Longcore, T., C. S. Lam, and J. P. Wilson. 2004. Analysis of butterfly survey data and methodology from San Bruno Mountain Habitat Conservation Plan (1982–2000) 1. Status and trends. Los Angeles, CA, University of Southern California GIS Research Laboratory Technical Report No. 1.

Longcore, T. 2004. Analysis of butterfly survey data and methodology from San Bruno Mountain Habitat Conservation Plan (1982–2000) 2. Survey Methodology. Los Angeles, CA, University of Southern California GIS Research Laboratory Technical Report No. 2.

Longcore, T., R. Mattoni, C. Zonneveld, and J. Bruggeman. 2003. INsect Count Analyzer: a tool to assess responses of butterflies to habitat restoration. Ecological Restoration 21(1):60–61. See

Mattoni, R., T. Longcore, Z. Krenova, and A. Lipman. 2003. Mass rearing of the endangered Palos Verdes blue butterfly (Glaucopsyche lygdamus palosverdesensis: Lycaedindae). Journal of Research on the Lepidoptera 37:55–67.

Zonneveld, C., T. Longcore, and C. Mulder. 2003. Optimal schemes to detect the presence of insect species. Conservation Biology 17(2):476–487.

Mattoni, R., T. Longcore, C. Zonneveld, and V. Novotny. 2001. Analysis of transect counts to monitor population size in endangered insects: the case of the El Segundo blue butterfly, Euphilotes bernardino allyni. Journal of Insect Conservation 5(3):197–206.

Lipman, A., T. Longcore, R. Mattoni, and Y. Zhang. 1999. Habitat evaluation and reintroduction planning for the endangered Palos Verdes blue butterfly. UCLA Department of Geography. Final Technical Report to California Department of Fish and Game. 44 pp.

Mattoni, R., G. F. Pratt, T.R. Longcore, J. F. Emmel and J. N. George. 1997. The endangered quino checkerspot butterfly, Euphydryas editha quino (Lepidoptera: Nymphalidae). Journal of Research on the Lepidoptera 34:99–118.

Longcore, T. 1997. The endangered Delhi Sand Dunes. Western Tanager 63(8):1-2.