Grantee Research Project Results
Abstract: Molecular Techniques for Predicting Invasion Potential: Comparisons among Native and Invasive Kelp SpeciesEPA Grant Number: F5D10652
Title: Abstract: Molecular Techniques for Predicting Invasion Potential: Comparisons among Native and Invasive Kelp Species
Investigators: Henkel, Sarah K.
Institution: University of California - Santa Barbara
EPA Project Officer: Packard, Benjamin H
Project Period: September 19, 2005 through June 13, 2008
Project Amount: $108,316
RFA: STAR Graduate Fellowships (2005) RFA Text | Recipients Lists
Research Category: Academic Fellowships
This research focuses on the problem of an invasive kelp and how it is capable of colonizing new habitats. Much research has been conducted at the organism level on non-native species; however, little physiological work has been done on invasive seaweeds. I will employ a molecular technique to identify physiological characters that may facilitate the invasion of a particular species. In physiological ecology, an established index of thermotolerance is the up-regulation of heat shock genes (termed the heat shock response) by which heat shock proteins (Hsps) are rapidly synthesized. The first goal of this study is to examine the up-regulation of Hsps as a means to assess the physiological plasticity and tolerances of the Eastern Pacific invasive kelp, Undaria pinnatifida, as compared to two potentially competing native kelps: Egregia menziesii and Eisenia arborea. I hypothesize that the invasive will exhibit broader temperature tolerance than the native kelp species at sites where they co-exist. The second goal of this study is to examine plasticity in the heat shock response across a wide range of environmental conditions. I will conduct thermotolerance studies using Hsps on native kelps from a broad latitudinal range, the invasive kelp where it exists, and on juvenile stages of both. I hypothesize that the physiological response is broadly variable across the gradient of temperatures present along the biogeographic range, which exceeds that observed at the local level. Temperature is thought to be one of the primary factors determining the geographic boundaries of seaweeds ; thus, this study will elucidate a possible mechanism for how seaweeds cope with temperature stress and what affects their ability to expand their range. Knowledge of the potential for Undaria pinnatifida to expand beyond its current level of invasion is important for assessing where to focus prevention efforts as well as for establishing methods to control transmission. Use of this technique may also help natural resource managers predict future invasions by other species and guide the allocation of management and financial resources to species that show the greatest threat of widespread invasion.
Kelps, an important group of seaweeds, are significant members of marine communities, holding scenic, recreational, economic, and environmental value. This research focuses on the invasive Asian kelp, Undaria pinnatifida, and how it is capable of spreading. Invasive species can disrupt food webs and have economic impacts. I will examine how temperature tolerance play a role in invasions and range expansions. An established measure of temperature tolerance is the production of heat shock proteins (Hsps). This project will study Hsps and how they are involved in invasion and spread. Knowledge of the potential for Undaria to spread is important for prevention as well as control of this invader.