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. 2010 Dec 23;6(6):777-80.
doi: 10.1098/rsbl.2010.0373. Epub 2010 Jun 9.

Are snake populations in widespread decline?

C J Reading  1 , L M Luiselli, G C Akani, X Bonnet, G Amori, J M Ballouard, E Filippi, G Naulleau, D Pearson, L Rugiero
Affiliations

Are snake populations in widespread decline?

C J Reading et al. Biol Lett. .

Abstract

Long-term studies have revealed population declines in fishes, amphibians, reptiles, birds and mammals. In birds, and particularly amphibians, these declines are a global phenomenon whose causes are often unclear. Among reptiles, snakes are top predators and therefore a decline in their numbers may have serious consequences for the functioning of many ecosystems. Our results show that, of 17 snake populations (eight species) from the UK, France, Italy, Nigeria and Australia, 11 have declined sharply over the same relatively short period of time with five remaining stable and one showing signs of a marginal increase. Although the causes of these declines are currently unknown, we suspect that they are multi-faceted (such as habitat quality deterioration, prey availability), and with a common cause, e.g. global climate change, at their root.

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Figures

Figure 1.
Figure 1.
Annual total number of individuals found for each declining snake species population. Axis 1: filled left-pointed triangles, Va1; filled circles, Va2; filled squares, Va3; filled triangles, Vu1; filled inverted triangles, Vu2; cirlces with crosses, Ca; filled diamonds, Hv1. Axis 2: open circles, Bg; open squares, Bn; open triangles, Pr; open diamonds, Zl1. Values shown for Va1 are one-third of true values. See table 1 for key to snake species abbreviations and country of origin.
Figure 2.
Figure 2.
Annual total number of individuals found for five stable and one increasing snake species population. Filled circles, Nn1; filled squares, Nn2; filled triangles, Zl2; filled inverted triangles, Dj; open circles, Hv2; filled diamonds, Ns. Linear regression analyses of the change in the number of individuals of each species present over time. Stable populations: Nn1-nos = −684 + 0.350 year, p = 0.476, r2 = 0.052, n = 12; Nn2-nos = 6 + 0.04 year, p = 0.987, r2 = 0.0, n = 15; Zl2-nos = −522 + 0.290 year, p = 0.814, r2 = 0.005, n = 13; Dj-nos = −237 + 0.136 year, p = 0.548, r2 = 0.031, n = 14; Ns-nos = 2936–1.40 year, p = 0.537, r2 = 0.039, n = 12. Increasing population: Hv2-nos = −3813 + 1.93 year, p = 0.037, r2 = 0.339, n = 13. See table 1 for a key to species abbreviations.
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References

    1. Alford R. A., Dixon P. M., Pechmann J. H. K.2001Global amphibian population declines. Nature 412, 499–500 (doi:10.1038/35087658) - DOI - PubMed
    1. Andersen T., Carstensen J., Hernández-García E., Duarte C. M.2008Ecological thresholds and regime shifts: approaches to identification. Trends Ecol. Evol. 24, 49–57 - PubMed
    1. Collins J. P., Storfer A.2003Global amphibian declines: sorting the hypotheses. Divers. Distrib. 9, 89–98
    1. Feyrer F., Nobriga M. L., Sommer T. R.2007Multidecadal trends for three declining fish species: habitat patterns and mechanisms in the San Fransisco estuary, California, USA. Can. J. Fish. Aquat. Sci. 64, 723–734 (doi:10.1139/F07-048) - DOI
    1. Gibbons J. W., et al. 2000The global decline of reptiles, déjà vu amphibians. Bioscience 50, 653–666

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