@article {94821, title = {How Birds Combat Ectoparasites}, journal = {The Open Ornithology Journal}, volume = {3}, year = {2010}, pages = {41 - 71}, type = {Open Access}, abstract = {

Birds are plagued by an impressive diversity of ectoparasites, ranging from feather-feeding lice, to feather- degrading bacteria. Many of these ectoparasites have severe negative effects on host fitness. It is therefore not surprising that selection on birds has favored a variety of possible adaptations for dealing with ectoparasites. The functional signifi- cance of some of these defenses has been well documented. Others have barely been studied, much less tested rigorously. In this article we review the evidence - or lack thereof - for many of the purported mechanisms birds have for dealing with ectoparasites. We concentrate on features of the plumage and its components, as well as anti-parasite behaviors. In some cases, we present original data from our own recent work. We make recommendations for future studies that could im- prove our understanding of this poorly known aspect of avian biology.

}, keywords = {anting, dusting, Fumigation, grooming, molt, oil, preening, sunning}, issn = {18744532}, doi = {10.2174/1874453201003010041}, url = {http://benthamopen.com/ABSTRACT/TOOENIJ-3-41}, author = {Clayton,Dale H. and Koop,Jennifer A. H. and Christopher W. Harbison and Brett R. Moyer and Sarah E. Bush} } @article {47095, title = {Is melanin a defense against feather-feeding lice?}, journal = {Auk}, volume = {123}, year = {2006}, month = {2006}, pages = {153 - 161}, abstract = {

The adaptive basis of plumage color has received much attention, including the finding that color can reveal information about parasite loads to potential mates. A related possibility, that color may be a direct defense against parasites, has received less attention. Melanin makes feathers tough and more resistant to wear and tear. Melanin may also make feathers more difficult for feather-feeding parasites to eat. We explored the role of melanin as a possible ectoparasite defense using Rock Pigeons (Columba livia) and their feather-feeding lice (Insecta: Phthiraptera). Rock Pigeons are an ideal species for such work because of the extreme variation in the feathers of different color morphs, ranging from melanin-rich black to melanin-free white individuals. We tested the effect of melanin on lice in several ways. First, we compared the natural louse loads of free-ranging pigeons to see whether the more melanistic color morphs had fewer lice. We also did laboratory assays in which we measured the survival and reproductive success of pigeon lice forced to feed on feathers with different amounts of melanin, and we compared the quantities of feather material consumed by these lice. Finally, we tested the habitat and feeding preferences of lice exposed to feathers with different amounts of melanin. None of our tests revealed any effect of melanin on lice. We conclude that melanin is not, at least in Rock Pigeons, a defense against feather lice.

}, keywords = {color, Columba, Columbiformes, ectoparasites, livia, Pigeon, plumage, preening, rock}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/46200.pdf}, author = {Sarah E. Bush and Kim,Dukgun and Brett R. Moyer and Lever,Jackson and Clayton,Dale H.} } @article {47029, title = {Risk that websites could break code of anonymity}, journal = {Nature}, volume = {413}, year = {2001}, month = {2001}, pages = {347}, keywords = {anonymity, manuscript, peer review}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/46114.pdf}, author = {David L. Reed and Brett R. Moyer and Clayton,Dale H.} } @article {45880, title = {Adaptive significance of avian beak morphology for ectoparasite control}, journal = {Proceedings of the Royal Society of London, Series B, Biological Sciences}, volume = {272}, year = {2005}, month = {2005}, pages = {811 - 817}, abstract = {

The beaks of Darwin\&$\#$39;s finches and other birds are among the best known examples of adaptive evolution. Beak morphology is usually interpreted in relation to its critical role in feeding. However, the beak also plays an important role in preening, which is the first line of defence against harmful ectoparasites such as feather lice, fleas, bugs, flies, ticks and feather mites. Here, we show a feature of the beak specifically adapted for ectoparasite control. Experimental trimming of the tiny (1-2 mm) maxillary overhang of rock pigeons (Columba livia) had no effect on feeding efficiency, yet triggered a dramatic increase in feather lice and the feather damage they cause. The overhang functions by generating a shearing force against the tip of the lower mandible, which moves forward remarkably quickly during preening, at up to 31 timesper second. This force damages parasite exoskeletons, significantly enhancing the efficiency of preening for parasite control. Overhangs longer than the natural mean of 1.6mm break significantly more often than short overhangs. Hence, stabilizing selection will favour overhangs of intermediate length. The adaptive radiation of beak morphology should be re-assessed with both feeding and preening in mind.

}, keywords = {adaptation, Analysis of Variance, animals, Beak/anatomy \& histology/physiology, Biomechanics, Columbidae, Comparative Study, Feathers/parasitology, Feeding Behavior/physiology, grooming, lice, Research Support, Non-U.S. Gov{\textquoteright}t, Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S., Utah, Video Recording}, isbn = {0962-8452}, url = {http://phthiraptera.info/sites/phthiraptera.info/files/45880.pdf}, author = {Clayton,Dale H. and Brett R. Moyer and Sarah E. Bush and Jones,T. G. and Gardiner,D. W. and Rhodes,B. B. and Goller,F.} } @article {43339, title = {An experimental test of the importance of preen oil in Rock Doves (Columba livia)}, journal = {Auk}, volume = {120}, year = {2003}, month = {2003}, pages = {490 - 496}, abstract = {

Most species of birds have a uropygial gland, also known as a preen gland, which produces oil that birds spread through their plumage when preening. The plumage of waterfowl deprived of uropygial oil becomes brittle and is subject to breakage. For other groups of birds, however, the importance of preen oil remains unclear. Previous workers have argued that preen oil may serve little or no function in Columbiforms (pigeons and doves). We tested that assertion by removing uropygial glands from Rock Doves (Columba livia) and assessing their plumage condition after several months. The results of that experiment showed significant degradation of plumage in the absence of oil. Our results are the first rigorous demonstration that preen oil is important for plumage condition in nonwaterfowl. We tested one possible function of preen oil\—that it has insecticidal properties and that reduction in plumage condition on birds without glands is due to an increase in ectoparasites. We tested that hypothesis for feather-feeding lice (Phthiraptera:Ischnocera) using both in vitro and in vivo experiments. Lice raised in an incubator died more rapidly on feathers with preen oil than on feathers without oil, which suggests that preen oil may help combat lice. However, removal of the preen gland from captive birds had no significant effect on louse loads over the course of a four-month experiment. Although the results of our in vivo experiments suggest that preen oil may not be an important defense against lice, further experiments are needed. We also consider the possibility that preen oil may protect birds against other plumage degrading organisms, such as bacteria and fungi.

}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/41856.pdf}, author = {Brett R. Moyer and Alex N. Rock and Clayton,Dale H.} } @inbook {43342, title = {Avian defenses against ectoparasites}, booktitle = {Insect and Bird Interactions}, year = {2004}, month = {2004}, pages = {241 - 257}, publisher = {Intercept}, organization = {Intercept}, address = {Andover, U.K.}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/41859.pdf}, author = {Brett R. Moyer and Clayton,Dale H.}, editor = {vanEmden,H. F. and Rothschild,Miriam} } @article {43336, title = {Impact of feather molt on ectoparasites: Looks can be deceiving}, journal = {Oecologia}, volume = {131}, year = {2002}, month = {2002}, pages = {203 - 210}, doi = {10.1007/s00442-002-0877-9}, url = {https://phthiraptera.myspecies.info/sites/phthiraptera.info/files/41853_0.pdf}, author = {Brett R. Moyer and Gardner,David W. and Clayton,Dale H.} } @article {43337, title = {Low humidity reduces ectoparasite pressure: Implications for host life history evolution}, journal = {Oikos}, volume = {97}, year = {2002}, month = {2002}, pages = {223 - 228}, abstract = {

A parasite\’s potential effect, or \‘\‘pressure\’\’, can influence the life history strategy of its host. In environments with high parasite pressure, hosts invest more in anti-para- site defense, which may limit their investment in other life history components, such as survival. This tradeoff is difficult to study in natural populations because pressure is hard to quantify. Pressure is not necessarily correlated with the abundance of the parasite. A host population can be under high pressure, yet have few parasites, because members of the population have invested heavily in defense. Therefore, the extent to which parasite pressure varies among host populations, and the cause of such variation, remain largely undocumented. In this paper we show that birds in arid regions have fewer ectoparasitic lice than birds in humid regions. We show experimentally that low humidity reduces the number of lice on birds, even when host defense is held constant. Comparisons of ambient humidity to humidity beneath the plumage demonstrate that plumage does not provide a buffer for lice against low humidity. Our results confirm that an abiotic factor can cause substantial variation in parasite pressure among host populations. We suggest that humidity may influence host life history evolution through its impact on ectoparasites.

}, url = {https://phthiraptera.myspecies.info/sites/phthiraptera.info/files/41854_0.pdf}, author = {Brett R. Moyer and Drown,Devin M. and Clayton,Dale H.} } @article {43338, title = {Influence of bill shape on ectoparasite load in Western Scrub-jays}, journal = {Condor}, volume = {104}, year = {2002}, month = {2002}, pages = {675 - 678}, abstract = {

Populations of the Western Scrub-Jay (Aphelocoma californica) have bills specialized for feeding in their respective habitats. Populations in oak habitat have hooked bills, whereas those in pinyon habitat have pointed bills with a reduced maxillary overhang. Work on other bird species shows that the bill overhang is essential for efficient preening to control ectoparasites. Given the importance of this overhang, we predicted that louse-infested jays with pointed bills would have higher louse loads than those with hooked bills. We compared the number of lice on 65 pointed-billed (4 infested) and 105 hooked-billed (17 infested) birds. Despite their lower incidence of louse infestation, pointed-billed birds had significantly more lice than hooked-billed birds, supporting our prediction. While pointed bills enhance feeding in pinyon habitat, our results suggest that they may incur a cost of reduced preening efficiency. Evolution of bill shape has traditionally been interpreted mainly in terms of foraging. Our results suggest that selection for efficient preening may also play an important role.

Also: https://academic.oup.com/condor/article/104/3/675/5563150

}, doi = {https://doi.org/10.1093/condor/104.3.675}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/41855.pdf}, author = {Brett R. Moyer and Peterson,A. T. and Clayton,Dale H.} } @article {40220, title = {Sunning by Black Noddies (Anous minutus) may kill chewing lice (Quadraceps hopkinsi)}, journal = {Auk}, volume = {112}, year = {1995}, month = {1995}, pages = {1073 - 1077}, keywords = {coloniality, cost, ecology, ectoparasite, host, parasitism, reproduction, swallows}, url = {https://phthiraptera.myspecies.info/sites/phthiraptera.info/files/38551.pdf}, author = {Brett R. Moyer and Wagenbach,Gary E.} }