---
title: "Feeling lousy.  ectoparasite loads in Hawaiian Wedge-tailed Shearwaters"
---

# Feeling lousy.  ectoparasite loads in Hawaiian Wedge-tailed Shearwaters

*![lice paper](https://www.acap.aq/images/stories/acap/Birds/Shearwaters/Wedge_tailed/lice_paper.jpg)Graphical abstract from the publication*

 Mikinley Weaver ([Hawaiʻi Pacific University](https://www.hpu.edu/), Waimanalo, Hawaii, USA) and colleagues have published in the journal *[Parasitology Internatonal](https://www.sciencedirect.com/journal/parasitology-international) *on lice loads in [Wedge-tailed Shearwaters](https://datazone.birdlife.org/species/factsheet/wedge-tailed-shearwater-ardenna-pacifica) *Ardenna pacifica*from the Hawaiian island of Oahu*.*

 The paper’s abstract follows:

 “Ectoparasites were collected from 35 live *Ardenna pacifica* Gmelin chicks (wedge-tailed shearwaters) in October and November 2022 using a fumigant and plastic bag collection method.  Additionally, 206 naturally-deceased post-fledging grounded birds were sampled opportunistically over eight years (2015–2023), with fledglings collected during the fledging season (November – December) and adults collected during the breeding season (May – October).  Eight species of Phthiraptera were documented in samples from these birds.  While four species (*Halipeurus mirabilis* Thompson*, Trabeculus hexakon* Waterson*, Austromenopon paululum* (Kellogg & Chapman)*,* and *Naubates harrisoni* Bedford) were present on chicks that had fledged and subsequently “fallen out”, only *H. mirabilis* was present on chicks that had not yet fledged. *Saemundssonia puellula* Timmermann, and *Longimenopon puffinus* Thompson, were only collected from adult fallout birds in the spring.  Of the recorded ectoparasites, four species (*H. mirabilis, T. hexakon, A. paululum,* and *N. harrisoni)* constituted a species assemblage that did not significantly vary from year to year.  Lice abundance and diversity varied across bird age classes (pre-fledging chicks, fledged chicks, adults), but a significant increase in lice abundance during 2015 coincided with a major El Niño event, suggesting that the ectoparasite loads may be affected by external conditions such as air temperature.  There was also a significant increase in lice prevalence between pre-fledging and fledged chicks, which likely coincided with the lice hatching.  These results underscore the consistency of lice assemblages on *A. pacifica,* while highlighting the influence of endogenous (e.g., bird life history) and exogenous (e.g., weather) ecological factors.”

 **Reference:**

 Weaver, M.D., Brown, S.M. & Hyrenbach, K.D. 2026.  The traveling insects: ectoparasite records on Hawaiian wedge-tailed shearwaters, *Ardenna pacifica*, with a focus on Phthiraptera,  *[Parasitology International](https://www.sciencedirect.com/science/article/abs/pii/S1383576925001151)*[110, 103142. doi.org/10.1016/j.parint.2025.103142](https://www.sciencedirect.com/science/article/abs/pii/S1383576925001151).

 *John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 05 March 2026*