AuthorsYearTitleJournal pdfSource
Borelli, Allesina, Amarasekare, Arditi, Chase, Damuth, Holt, Logefet, Novak, Rohr, Rossberg, Spencer, Tran & Ginzburgin pressTrends in Ecology & Evolution
Terry & Novakin pressGeology
Novak & Tinker2015Oecologia178: 61-74pdf
Beas-Luna, Novak, Carr, Tinker, Black, Caselle, Hoban, Malone, Iles2014PLoS ONE9(10): e109356pdflink
Novak2013Proceedings of the Royal Society B280: 20131415request
Kenner, Estes, Tinker, Bodkin, Cowen, Harrold, Hatfield, Novak, Rassweiler & Reed2013Ecology (Data paper)94(11): 2654pdflink
Yeakel, Guimarães, Novak, Fox-Dobbs & Koch2012Journal of the Royal Society Interface9: 3219-3228pdf SOMlink
Twardochleb, Novak & Moore2012
Ecological Applications
Cover image
22(4): 1162–1171pdflink
Tinker, Guimarães, Novak, Marquitti, Bodkin, Staedler, Bentall & Estes2012Ecology Letters15(5): 475-483pdf SOMlink
Novak, Moore & Leidy2011Global Change Biology17: 3714-3723pdflink
Yeakel, Novak, Guimarães, Dominy, Koch, Ward, Moore & Semmens2011PLoS One6(7): e22015pdflink
Novak, Wootton, Doak, Emmerson, Estes & Tinker2011Ecology (Concepts & Synthesis)
Highlighted by F1000
92(4): 836-846pdflink
Yeakel, Stiefs, Novak & Gross2011Theoretical Ecology
Highlighted by F1000
4(2): 179-194pdflink
Bolnick, Amarasekare, Araújo, Bürger, Levine, Novak, Schreiber, Urban & Vasseur 2011Trends in Ecology & Evolution26(4): 183-191pdflink
DeAngelis, Wolkowicz, Lou, Jian, Novak, Svanbäck, Araújo, Jo & Cleary2011The American Naturalist178(1): 15-29pdflink
Novak2010Ecology91(8): 2394-2405pdflink
Novak & Wootton2010Oikos119: 1057-1063pdf
Novak & Wootton2008Ecology (Report)89(8): 2083-2089pdflink
Doak, Estes, Halpern, Jacob, Lindberg, Lovvorn, Monson, Tinker, Williams, Wootton, Carroll, Emmerson, Micheli & Novak2008Ecology (Concepts & Synthesis)89(4): 952-961pdflink
Novak2004Crustaceana77(5): 603-620pdflink


Dissertations, Honors projects & Reports


Moulvi2014Complex networks in kelp forest ecosystems: Visualizing big dataOSUURSA Engagepdf

Two elements of food webs add significantly to their complexity: The presence of trophic omnivores and the nonlinear nature of predator-prey interactions. I introduce a new observational method for estimating the strengths of species interactions that accounts for the indeterminacy of omnivorous indirect effects and the saturating functional responses that predators exhibit. I present an empirical support for the method’s accuracy by applying it to two populations of the predatory whelk, Haustrum (= Lepsiella) scobina, that is common to the rocky intertidal shores of New Zealand, and comparing these interaction strength estimates with those derived from experimental manipulations of H. scobina’s populations.
I then test two key predictions of intraguild predation theory by investigating how species abundances, food web structure and species interactions strengths change across six omnivorous food webs along a gradient of productivity present around New Zealand’s coastline. I find that the intermediate predator, H. scobina, is the superior competitor for shared prey, as predicted by theory. Counter to theory, however, I show that it is the omnivorous whelk, H. haustorium, that is the superior competitor when all prey are considered, and that H. scobina’s abundance increases with increasing productivity. My analyses reveal clear and regular cross-gradient shifts in interactions that can be incorporated into future modeling efforts.
Finally, I ask to what degree whelk feeding rates are saturated with respect to prey densities and, by extending and parameterizing the classic Rosenzweig-MacArthur model, ask whether empirical interactions are nonlinear enough to affect the stability of whelk-prey dynamics. Results indicate that feeding rates are not strongly saturated and that increasing diet richness has a non-additive effect on a predator’s saturation such that alternative prey have a stabilizing effect on whelk-prey dynamics. I thereby offer a new mechanism by which generalist predators stabilize the dynamics of their species-rich food webs.
My dissertation brings empirical data to bear on the importance of omnivory and the nonlinear nature of trophic interactions. Furthering our understanding of these food web features can contribute much to both the conceptual and applied goals of ecology.