backResearcher Profile

Ladd Erik Johnson

Job Title: Associate Professor/ Professeur agrégé
Employer: Université Laval
Place of Birth: Yreka, CA, USA
Public School attended: Jackson Street Elementary School
High School attended: Yreka High School
Further Education: Oregon State University (B.Sc. - 1980, Biology), University of Washington (Ph.D. - 1989, Zoology).
Geographic focus of research: Québec - St-Lawrence Estuary, Gulf of St. Lawrence, USA - Michigan and Indiana, France - northwestern coast

Brief synopsis of current research:
1. Marine ecology: biological and physical processes influencing marine benthic communities, especially those affecting the recruitment of intertidal and subtidal macroalgae (e.g., desiccation, herbivory, hydrodynamics). Ultimate goal = the development of biophysical models for predicting the development and stability of macroalgal populations.

2. Biological invasions: mechanisms of the introduction and dissemination of aquatic invasive species within and between ecosystems, especially dispersal vectors, and the ecology of invading species early in the process of colonization.

Mailing address:
Professeur adjoint/Assistant Professor, Departement de biologie, Universite Laval, 2056 Pavillon Alexandre-Vachon, Quebec, QC G1K 7P4
Phone: (418)656-2131 ext. 2266; Fax: (418)656-2339

Recent Publications:

Brawley, S.H., L.E. Johnson, G.A. Pearson, V. Speransky, R. Li & E. Serrão. 1999. Gamete release at low tide in fucoid algae: maladaptive or advantageous? American Zoologist 39: 218-229.

Johnson, L.E. &. S.H. Brawley, 1998. Dispersal and recruitment of a canopy-forming intertidal alga: the relative roles of propagule availability and post-settlement processes. Oecologia 117: 517-526.

Johnson, L.E. and D.K. Padilla. 1996. Geographic spread of exotic species: ecological lessons and opportunities from the invasion of the zebra mussel Dreissena polymorpha. Biological Conservation 78: 23-33.

Johnson, L.E. and J.T. Carlton. 1996. Post-establishment spread in large-scale invasions: dispersal mechanisms of the zebra mussel Dreissena polymorpha. Ecology 77: 1686-1690.

Johnson, L.E. 1994. Enhanced settlement on microtopographical high points by the intertidal red alga Halosaccion glandiforme. Limnology and Oceanography 39: 1893-1902.

As an American who has studied at a number of institutions of higher learning, I am exceedingly pleased with my experiences in Canada where resources are directed towards long term research programs that permit a deeper understanding of scientific subjets and problems.