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Spatial and temporal variation in macroparasite communities of three-spined stickleback
- REBECCA E. YOUNG, ANDREW D. C. MACCOLL
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- Journal:
- Parasitology / Volume 144 / Issue 4 / April 2017
- Published online by Cambridge University Press:
- 20 October 2016, pp. 436-449
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Patterns in parasite community structure are often observed in natural systems and an important question in parasite ecology is whether such patterns are repeatable across time and space. Field studies commonly look at spatial or temporal repeatability of patterns, but they are rarely investigated in conjunction. We use a large dataset on the macroparasites of the three-spined stickleback, Gasterosteus aculeatus L., collected from 14 locations on North Uist, Scotland over an 8-year period to investigate: (1) repeatability of patterns in parasite communities among populations and whether variation is consistent across years, (2) whether variation between years can be explained by climatic variation and progression of the season and (3) whether variation in habitat characteristics explain population differences. Differences in relative abundance and prevalence across populations were observed in a number of parasites investigated indicating a lack of consistency across years in numerous parasite community measures; however, differences between populations in the prevalence and abundance of some parasites were consistent throughout the study. Average temperature did not affect parasite community, and progression of the season was only significant for two of 13 community measures. Two of the six habitat characteristics investigated (pH and calcium concentration) significantly affected parasite presence.
Consistent differences in macroparasite community composition among populations of three-spined sticklebacks, Gasterosteus aculeatus L.
- JOB DE ROIJ, ANDREW D. C. MacCOLL
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- Journal:
- Parasitology / Volume 139 / Issue 11 / September 2012
- Published online by Cambridge University Press:
- 19 July 2012, pp. 1478-1491
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Parasite ecologists are often interested in the repeatability of patterns in parasite communities in space and/or time, because of implications for the dynamics of host-parasite interactions. Field studies usually examine temporal and spatial variation in isolation or limit themselves to a small number of host populations. Here, we studied the macroparasite communities of 12 populations of three-spined stickleback, Gasterosteus aculeatus L., on North Uist, Scotland, separated by small geographical distances, during the breeding season in 2 consecutive years (2007 and 2008) to determine: (1) the extent of spatial variation in macroparasite communities, (2) whether this variation is consistent across years, and (3) whether habitat characteristics can explain differences in macroparasite community composition among populations. We found substantial variation in parasite communities among populations. Generally, measures of parasite community composition were higher in 2008 than in 2007, but this effect of year was consistent across populations, such that the relative differences in these measures among populations changed little between years. These data suggest that there is short-term stability in the spatial variation in macroparasite communities of North Uist sticklebacks. However, none of the 5 habitat characteristics measured explained spatial variation in any measure of parasite community composition.
2 - The sheep of St Kilda
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- By T. H. Clutton-Brock, University of Cambridge, J. M. Pemberton, University of Edinburgh, T. Coulson, University of Cambridge, I. R. Stevenson, University of Stirling, A. D. C. MacColl, University of Sheffield
- Edited by T. H. Clutton-Brock, University of Cambridge, J. M. Pemberton, University of Edinburgh
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- Book:
- Soay Sheep
- Published online:
- 07 December 2009
- Print publication:
- 18 December 2003, pp 17-51
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Summary
Introduction
Sheep were domesticated in the Near East around 10 000 years ago and spread into Western Europe from there (J. Clutton-Brock 1981). Sheep similar to Soays had reached the Orkneys by 4000 bc and the sheep population of St Kilda may have originated around that date. In many aspects of their anatomy and physiology, they appear to be intermediate between contemporary domestic sheep and wild sheep (Boyd and Jewell 1974; Jewell 1986).
To understand the unusual dynamics of Soay sheep and their consequences for selection and adaptation, it is important to know something of their history as well as of the human inhabitants of St Kilda. The first two sections of this chapter describe the islands of St Kilda (section 2.2) and their history (section 2.3). Subsequent sections describe the appearance and anatomy of Soay sheep (section 2.4), their feeding ecology (section 2.5) and their reproductive system (section 2.6). Since variation in fecundity and neonatal survival affect the growth rate of the population, we describe the factors affecting the early development of lambs (section 2.7) as well as the factors affecting winter survival in juveniles and yearlings (section 2.8). Finally section 2.9 reviews the costs of reproduction and other factors affecting mortality in adults.
The islands of St Kilda
The four main islands of the St Kilda archipelago lie 160 km to the north-west of the Scottish mainland (Fig. 1.1).
3 - Population dynamics in Soay sheep
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- By T. H. Clutton-Brock, University of Cambridge, B. T. Grenfell, University of Cambridge, T. Coulson, University of Cambridge, A. D. C. MacColl, University of Sheffield, A. W. Illius, University of Edinburgh, M. C. Forchhammer, University of Copenhagen, K. Wilson, University of Stirling, J. Lindström, University of Glasgow, M. J. Crawley, Imperial College London, S. D. Albon, Centre for Ecology and Hydrology, Banchory: UK
- Edited by T. H. Clutton-Brock, University of Cambridge, J. M. Pemberton, University of Edinburgh
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- Book:
- Soay Sheep
- Published online:
- 07 December 2009
- Print publication:
- 18 December 2003, pp 52-88
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Summary
Introduction
A conspicuous feature of many naturally limited populations of long-lived vertebrates is their relative stability. Both in populations that are regulated by predation or culling and in food-limited populations, population size can persist at approximately the same level for decades or even centuries (Runyoro et al. 1995; Waser et al. 1995; Clutton-Brock et al. 1997a; Newton 1998). The persistent fluctuations shown by Soay sheep and by some other island populations of ungulates (Boyd 1981; Leader-Williams 1988; Boussès 1991) raise general questions about the causes and consequences of variation in the stability of populations (see section 1.2). How regular are they? How are they related to population density? What are their immediate causes? To what extent do fluctuations in food availability, parasite number or predator density contribute to them? And what are their effects on development and on the phenotypic quality of animals born at contrasting population densities? And how much do changes in phenotype contribute to changes in dynamics?
As yet, there are very few cases where we understand either the ecological causes or the demographic consequences of persistent fluctuations in the size of naturally regulated populations of mammals (Hanski 1987; Saether 1997). Since we are able to monitor the growth, movements, breeding success and survival of large samples of individuals as population density changes, the Soay sheep offer an opportunity to investigate the causes and consequences of changes in population size with unusual precision (see Chapter 1).