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Demography and population ecology


Long-term study of the grass Bouteloua rigidiseta

Since 1983 an annual census has been made of a set of permanent plots located in open grassy patches in a live oak/Ashe juniper savanna in central Texas. Data from these plots have provided the basis for on ongoing study of plant population dynamics and regulation, especially of the native perennial grass Bouteloua rigidiseta (Texas grama grass).  

Fowler, N. L., and C. M. Pease. 2010. Temporal variation in the carrying capacity of a perennial grass population. American Naturalist 175:504-512.

Fowler, N. L., R. D. Overath, and C. M. Pease. 2006. Detection of density dependence requires density manipulations and calculation of λ. Ecology 87:655-664.

Fowler, N. L. 1995. Density-dependent demography in two grasses: a five-year study. Ecology 76:2145-2164.

graph of Bouteloua densityplotter used for censuses

Modeling demographic heterogeneity

demographic heterogeneity poster (Batchelor and Fowler 2003)


Effects of simulated grazing on Bothriochloa ischaemum population dynamics

Bethany Gabbard compared clipped and unclipped plots in a field population of this invasive grass to quantify the effects of defoliation on life history components, population structure, and λ.

Bothriochloa ischaemum population dynamics poster (Gabbard & Fowler 2004)

bethany plotting kr

Demography of the invasive Centaurea stoebe (spotted knapweed) in New York State

Norma Fowler, co-PIs Jessica Gurevitch and Catherine Graham of SUNY-Stoney Brook, plus Ana González (UT), Emily Rollinson, Ed Lowry, and Jorge Velasquez (SUNY), are investigating the population dynamics of a new invasion of this serious weed in the Adirondack Mountains and on Long Island, two constrasting parts of New York State.  The primary role of Fowler and her lab will be in statistical analysis of demographic data and the construction and analysis of demographic models.

cemtaurea stoebe

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