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A comparative evaluation of northern and southern Ixodes scapularis questing height and hiding behaviour in the USA

Published online by Cambridge University Press:  10 August 2020

Mackenzie Tietjen*
Affiliation:
Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX77843, USA
Maria D. Esteve-Gasent
Affiliation:
Department of Veterinary Pathobiology, Texas A&M University, 4467 TAMU, College Station, TX77843, USA
Andrew Y. Li
Affiliation:
USDA, ARS, Invasive Insect Biocontrol and Behavior Laboratory, 10300 Baltimore Avenue, Beltsville, MD20705, USA
Raul F. Medina
Affiliation:
Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX77843, USA
*
Author for correspondence: Mackenzie Tietjen, E-mail: [email protected]

Abstract

Ticks display a distinct type of host-seeking behaviour called questing. It has been proposed that the questing behaviour of Ixodes scapularis explains the geographic variation in Lyme disease (LD) risk in the eastern USA because the northern population has been shown to quest more often than the southern population. The height at which questing occurs is variable and this study aimed to characterize questing height for I. scapularis. Ticks were collected from a northern and southern state (i.e. Maryland and Texas) and bioassays were conducted. We report that nymphs from Texas quested at lower heights compared to nymphs from Maryland. In addition, only Texas nymphs exhibited a behaviour we call ‘hiding behaviour’. These results may reflect the different composition of hosts between these two areas as the south has a higher abundance of lizards. In contrast, there was no significant difference in questing height between Maryland adults and Texas adults which was to be expected since adults are feeding on white-tailed deer in both locations. If all southern I. scapularis nymphs are questing at lower heights, this might make them less likely to come into contact with humans and this may be contributing to the geographical difference in LD prevalence.

Type
Research Article
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

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Footnotes

Current address: USDA–ARS Knipling–Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Rd. Kerrville, TX 78028, USA.

This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation by the USDA for its use. The USDA is an equal opportunity provider and employer.

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