HCNSO Student Theses and Dissertations

Copyright Statement

All rights reserved. This publication is intended for use solely by faculty, students, and staff of Nova Southeastern University. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, now known or later developed, including but not limited to photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author or the publisher.


Water Chemistry Effects on Apple Snail (Pomacea paludosa, Say) Reproductive Patterns in the Northern Everglades

Defense Date


Document Type

Thesis - NSU Access Only

Degree Name

M.S. Coastal Zone Management


Oceanographic Center

First Advisor

Jennifer S. Rehage

Second Advisor

Philip Darby

Third Advisor

Rebekah Gibble

Fourth Advisor

David Kerstetter


Canals surrounding the Everglades carry enriched and polluted water high in minerals and nutrients. These enriched waters impact adjacent marsh habitats, altering flora and fauna species and abundance. Multiple studies have found gradients in nutrient levels as a function of distance from canals and emphasize the sensitivity of some organisms to these changes in water chemistry. Florida apple snails, Pomacea paludosa Say, are just one of many Everglades species sensitive to changes in water chemistry. They serve as an important staple in the diets of many Everglades predators including turtles, crayfish, limpkins and most importantly the endangered snail kite, Rostrahamus sociabilis which feeds almost exclusively on the apple snail. To examine potential effects of water chemistry on apple snail breeding patterns, we observed snail egg size, egg number per clutch, and carbon and nitrogen contents along water chemistry gradients and among snail breeding months at the Arthur R. Marshall Loxahatchee National Wildlife Refuge. Egg number per clutch and egg diameters were greatest in the most impacted zones and lowest in the pristine, interior zone. Carbon contents of eggs were highest in the interior and east side of the Refuge and lowest in the west side. Nitrogen contents of eggs were highest in the interior and west side of the Refuge, and lowest in the east side. Significant, albeit weak, positive trends were found between N content and egg diameter, C content and egg diameter, and between egg number per clutch and egg diameter, but only among specific zones and months. Results from this study suggest that snails in areas of the Refuge that are influenced by canal-water may produce greater numbers of apple snail offspring with greater egg diameters than those in less impacted areas. However, we do not know if this translates into higher hatchling success and survival.

This document is currently not available here.

To access this thesis/dissertation you must have a valid nova.edu OR mynsu.nova.edu email address and create an account for NSUWorks.

Free My Thesis

If you are the author of this work and would like to grant permission to make it openly accessible to all, please click the Free My Thesis button.

  Link to NovaCat