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Impacts of agriculture on the parasite communities of northern leopard frogs (Rana pipiens) in southern Quebec, Canada

Published online by Cambridge University Press:  03 August 2007

K. C. KING ,
J. D. McLAUGHLIN ,
A. D. GENDRON ,
B. D. PAULI ,
I. GIROUX ,
B. RONDEAU ,
M. BOILY ,
P. JUNEAU  and
D. J. MARCOGLIESE
K. C. KING*
Affiliation:
Department of Biology, Concordia University, Montreal, Quebec, CanadaH3G 1M8
J. D. McLAUGHLIN
Affiliation:
Department of Biology, Concordia University, Montreal, Quebec, CanadaH3G 1M8
A. D. GENDRON
Affiliation:
Fluvial Ecosystem Research Section, Aquatic Ecosystem Protection Research Division, Water Science and Technology Directorate, Science and Technology Branch, St. Lawrence Centre, Environment Canada, 105 rue McGill, Montreal, Quebec, CanadaH2Y 2E7
B. D. PAULI
Affiliation:
Canadian Wildlife Service, National Wildlife Research Centre, Carleton University, Ottawa, Ontario, CanadaK1A 0H3
I. GIROUX
Affiliation:
Ministère du Développement durable, de l'Environnement et des Parcs, Direction du suivi de l'état de l'environnement, Service de l'information sur les milieux aquatiques, 675 boul. René-Lévesque Est, Montreal, Quebec, CanadaG1R 5V7
B. RONDEAU
Affiliation:
Quebec Water Quality Monitoring and Surveillance Section, Water Quality Monitoring and Surveillance Science and Technology Branch, Environment Canada, 105 McGill, 7th floor, Montreal, Quebec, CanadaH2Y 2E7
M. BOILY
Affiliation:
Centre TOXEN, Université du Quèbec á Montréal, 141 ave. Président Kennedy, Montreal, Quebec, CanadaH2X 3Y7
P. JUNEAU
Affiliation:
Department of Biological Sciences-TOXEN, Université du Quèbec à Montréal, C.P. 8888, Succ. Centre-ville, Montreal, Quebec, CanadaH3C 3PB
D. J. MARCOGLIESE
Affiliation:
Fluvial Ecosystem Research Section, Aquatic Ecosystem Protection Research Division, Water Science and Technology Directorate, Science and Technology Branch, St. Lawrence Centre, Environment Canada, 105 rue McGill, Montreal, Quebec, CanadaH2Y 2E7
*
*Corresponding author: Present address, Department of Biology, Indiana University, Jordan Hall 142, 1001 East Third Street, Bloomington, Indiana 47405, USA. Tel: +812 855 3282. E-mail: kingkc@indiana.edu
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Summary

Given that numerous amphibians are suffering population declines, it is becoming increasingly important to examine the relationship between disease and environmental disturbance. Indeed, while many studies relate anthropogenic activity to changes in the parasitism of snails and fishes, little is known of the impact on the parasites of amphibians, particularly from agriculture. For 2 years, the parasite communities of metamorphic northern leopard frogs from 7 agricultural wetlands were compared with those from 2 reference wetlands to study differences in parasite community diversity and abundance of various species under pristine conditions and 3 categories of disturbance: only agricultural landscape, only pesticides, and agricultural landscape with pesticides. Agricultural (and urban) area was negatively related to species richness, and associated with the near absence of adult parasites and species that infect birds or mammals. We suggest that agriculture and urbanization may hinder parasite transmission to frogs by limiting access of other vertebrate hosts of their parasites to wetlands. The only parasite found at all localities was an unidentified echinostome infecting the kidneys. This parasite dominated communities in localities surrounded by the most agricultural land, suggesting generalist parasites may persist in disrupted habitats. Community composition was associated with dissolved organic carbon and conductivity, but few links were found with pesticides. Pollution effects may be masked by a strong impact of land use on parasite transmission.

Keywords

parasite communitiesamphibiansspecies richnessRana pipiensagriculturepesticidesland useurbanizationwetlands
Type
Research Article
Information
Parasitology , Volume 134 , Issue 14 , December 2007 , pp. 2063 - 2080
Copyright
Copyright © Cambridge University Press 2007

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