Download the full-sized PDF of Measuring and Interpreting Predation on Gastropod ShellsDownload the full-sized PDF



Permanent link (DOI):


Export to: EndNote  |  Zotero  |  Mendeley


This file is in the following communities:

Graduate Studies and Research, Faculty of


This file is in the following collections:

Theses and Dissertations

Measuring and Interpreting Predation on Gastropod Shells Open Access


Other title
hermit crab
Type of item
Degree grantor
University of Alberta
Author or creator
Stafford, Emily S.
Supervisor and department
Leighton, Lindsey (Earth and Atmospheric Sciences)
Examining committee member and department
Geerat J. Vermeij (Earth and Planetary Sciences, UC Davis)
Murray K. Gingras (Earth and Atmospheric Sciences)
G. Arturo Sanchez-Azofeifa (Biological Sciences)
A. Richard Palmer (Biological Sciences)
Department of Earth and Atmospheric Sciences

Date accepted
Graduation date
Doctor of Philosophy
Degree level
This dissertation focuses on problems and progress in studying crushing predation on gastropods in the Modern and the fossil record. Although crushing predation tends to be destructive, it is possible to gather data on crushing predation from multiple angles. Chapter 2 applies an ichnotaxonomic name, Caedichnus, to the trace created by peeling crab predators. Chapter 3 the relationship between shell repair frequency and predation mortality in a modern gastropod community. In this case, repair frequency was likely a direct product of variation in predator abundance and strength. Chapter 4 focused on hermit crabs, an organism that inhabits gastropod shells and exposes those shells to predation even after the original gastropod inhabitant has died. The predatory crabs showed no preference for snail or hermit crab prey, which may mean that hermit crab habitation does not significantly alter the crab-on-snail predation patterns present in a shell assemblage. Chapter 5 expanded on previous work by the author, using a method by G.J. Vermeij to estimate crushing predation in a gastropod assemblage even when individual instances of predatory damage cannot be identified. Vermeij Crushing Analysis (VCA) uses drilled shells to establish a baseline of taphonomic damage in a shell assemblage; the chapter refines and examines this method more deeply, in addition to applying the method to compare predation on modern and fossil gastropod shell assemblages. Chapter 6 is the culmination of the previous chapters, combining predatory traces, VCA, and repair frequency, as well as predatory shell drilling, to examine predation at multiple trophic levels in a Miocene-age fossil shell assemblage from Maryland.
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication
Stafford, E.S., L.R. Leighton, and C.L. Tyler (in press). Shell repair frequency tracks predator abundance in intertidal gastropods. Marine Ecology

File Details

Date Uploaded
Date Modified
Audit Status
Audits have not yet been run on this file.
File format: pdf (PDF/A)
Mime type: application/pdf
File size: 6176601
Last modified: 2015:10:22 07:19:00-06:00
Filename: Stafford_Emily_S_201501_PhD.pdf
Original checksum: 18d3945ac4b8a3bcd56933c420795b6f
Activity of users you follow
User Activity Date