Andrew O. (Ole) Shelton


Postdoctoral Scholar - Mangel Lab
Center for Stock Assessment Research (CSTAR)
University of California, Santa Cruz
ashelton(at)soe.ucsc.edu

I'm a marine biologist broadly interested in the life-histories of organisms and the connections between life-history, populations, and communities. I combine observational, experimental, and genetics data collected from natural populations with mathematical models to investigate the causes and consequences of life-history variation. I am particularly interested in the consequences of sex differences in life-history and the application of two-sex models to populations.

I recently started a postdoctoral appointment with Marc Mangel at UC Santa Cruz working on quantitative fisheries methods.

 

 

Research

I received my Ph.D in 2009 from the Department of Ecology and Evolution at the University of Chicago (advisor Dr. Cathy Pfister). My dissertation focused on the causes and consequences of skewed sex ratios in natural populations of two marine plants (surfgrass; Phyllospadix spp.). Surfgrass species have the unusual characteristic of having very biased sex ratios; males make up less than 20% of populations. My dissertation research was conducted on the Olympic penninsula in Washington state with Tatoosh Is. as my primary field site.

I have investigated the consequences of male rarity for the pollination biology of surfgrass (Shelton 2008), developed and applied genetic markers in concert with individual demographic data to determine when during surfgass life-history sex ratios arise (Shelton Ecology In Press), and created a two-sex population model to ask how sex-differences in life-history generate skewed sex ratios and which evolutionary scenarios were most likely responsible for the sex ratio bias observed in nature (Shelton Am Nat In Press). I have also manipulated the abundance of surfgrass in tidepools to explore the effect of surfgrass on the temperature regime and community of organisms present in tidepools (Shelton in review).

 

 
 

Current Projects

I am collaborating with scientists at NOAA's Southwest Fisheries Science Center to develop methods to account for uncertainty in rockfish landings data.

I am developing a project in collaboration with the Alaska Department of Fish and Game on herring populations in southeastern Alaska. I hope to use ADFGs long time-series of herring abundance and size-at-age data from multiple populations in SE Alaska to infer the amount of connectedness among herring populations. Additionally, I hope to use the these time-series in conjunction with time-series of environmentnal variables (e.g. ocean temperature) and predator abundances (e.g. Sea Lions) to try and tease apart the factors that are important drivers of herring populations.

 
 

Peer-Reviewed Publications

Shelton, A.O. The ecological and evolutionary drivers of female-biased sex ratios: two-sex models of a perennial seagrass. American Naturalist 175:302–315 (pdf)

Shelton, A.O. 2008. Skewed sex ratios, pollen limitation, and reproductive failure in the dioecious seagrass genus Phyllospadix. Ecology 89:3020-3029. (pdf)

Micheli, F., A.O. Shelton, S.M. Bushinsky, A.L.Chiu, K.W. Heiman, C.V. Kappel, M.C. Lynch, and J. Watanabe. 2008. Persistence and recovery of depleted marine invertebrates in marine reserves of central California. Biological Conservation 141:1078-1090.(pdf)

Shelton, A.O., D.A. Woodby, K. Hebert, and J. Witman. 2006. Age determination and spatial patterns of growth of the red sea urchin (Strongylocentrotus franciscanus) in southeast Alaska. Transactions of the American Fisheries Society 135:1670-1680. (pdf)

In Press:

Shelton, A.O. The origin of female-biased sex ratios in intertidal seagrasses (Phyllospadix spp.) Ecology

In Review:

Shelton, A.O. Environmental and community consequences of foundation species: surfgrass (Phyllospadix spp.) in tidepools. Journal of Experimental Marine Biology and Ecology.

Micheli, F., K.W. Heiman, C.V. Kappel, R.L. Martone, J. Martin, S.A. Sethi, G.C. Osio, S. Fraschetti, and A.O. Shelton. Pounding waves and pounding feet: natural and human disturbances structure rocky shores communities. Ecological Applications