You are here

Home

Harvard Forest >

Harvard Forest REU Symposium Abstract 2015

  • Title: When a Tree falls in a Forest, do ants care: a look at ant community diversity in response to foundation species loss in two forest systems
  • Author: Tess D McCabe (Bryn Mawr College)
  • Abstract:

    Eastern Hemlock and the Oak genus are foundational trees that are under threat from Hemlock woolly adelgid (HWA) and Sudden Oak Death, respectively. This experiment looks at the response of ant community composition to simulated impacts of pests and pathogens in the Harvard Forest Hemlock Removal Experiment (HF-HeRE) in Massachusetts and the Future of Oak Forests experiment at Black Rock Forest (BRF) in New York. The HF-HeRE consists of hardwood and hemlock controls, simulated adelgid infestation (hemlocks girdled), and salvage logging (removal of hemlock and merchantable hardwoods) plots. At BRF four treatments investigate effects of oak loss: all oaks girdled, 50% of oaks girdled, all non-oaks girdled, and a control (oaks and non-oaks were unmanipulated). At HF ants were sampled from 25 pitfall traps every year from 2003-2015, and at BRF ants were hand sampled during five years between 2006-2015. A non-parametric multivariate Analysis of Variance (npMANOVA) found significant effects of year, treatment, plot nested within treatment, and treatment year×treatment interaction. Non-metric multidimensional scaling (NMDS) plots of HF-HeRE treatments over time suggest that girdled and logged plots became more similar to hardwood control three years post-treatment and that hemlock control plots became more similar to hardwood control plots 6-8 years post-treatment and after the infestation of HWA to the forest In 2010. In contrast, an npMANOVA for BRF did not reveal any significant effects of treatment, year, or their interaction. These results suggest ant communities may be more resilient to the loss of oaks than to the loss of hemlocks.

  • Research Category: Biodiversity Studies; Ecological Informatics and Modelling; Historical and Retrospective Studies; Invasive Plants, Pests & Pathogens; Large Experiments and Permanent Plot Studies; Physiological Ecology, Population Dynamics, and Species Interactions