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Extinction of an introduced warm-climate alien species, Xenopus laevis, by extreme weather events.

Tinsley RC, Stott LC, Viney ME, Mable BK, Tinsley MC - Biol. Invasions (2015)

Bottom Line: In 2010, only a single individual was captured at each locality and further searching failed to record any others in repeated sampling up to 2014.We conclude that both populations are now extinct.The extinction of X. laevis in these areas indicates that even relatively long-established alien species remain vulnerable to rare extreme weather conditions.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ UK.

ABSTRACT

Invasive, non-native species represent a major threat to biodiversity worldwide. The African amphibian Xenopus laevis is widely regarded as an invasive species and a threat to local faunas. Populations originating at the Western Cape, South Africa, have been introduced on four continents, mostly in areas with a similar Mediterranean climate. Some introduced populations are also established in cooler environments where persistence for many decades suggests a capacity for long-term adaptation. In these cases, recent climate warming might enhance invasion ability, favouring range expansion, population growth and negative effects on native faunas. In the cool temperate UK, populations have been established for about 50 years in Wales and for an unknown period, probably >20 years, in England (Lincolnshire). Our field studies over 30 and 10 years, respectively, show that in favourable conditions there may be good recruitment, fast individual growth rates and large body size; maximum longevity exceeds 23 years. Nevertheless, areas of distribution remained limited, with numbers <500 in each population. In 2010, only a single individual was captured at each locality and further searching failed to record any others in repeated sampling up to 2014. We conclude that both populations are now extinct. The winters of 2009-2010 and 2010-2011 experienced extreme cold and drought (December 2010 was the coldest in 120 years and the third driest in 100 years). The extinction of X. laevis in these areas indicates that even relatively long-established alien species remain vulnerable to rare extreme weather conditions.

No MeSH data available.


Related in: MedlinePlus

Fieldwork area in North Lincolnshire, centred on 53°37′30″N, 0°40′14″W, north of Scunthorpe. Red triangles show localities of trapping in 2003–2010 where Xenopus laevis was never recorded (most sites trapped repeatedly in successive years). Data on the right of the map record habitats in which X. laevis occurred and results of surveying in 3 years, 2009–2011, showing numbers of trap-sessions at each site (arrows to a–h) and numbers of X. laevis caught
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Fig2: Fieldwork area in North Lincolnshire, centred on 53°37′30″N, 0°40′14″W, north of Scunthorpe. Red triangles show localities of trapping in 2003–2010 where Xenopus laevis was never recorded (most sites trapped repeatedly in successive years). Data on the right of the map record habitats in which X. laevis occurred and results of surveying in 3 years, 2009–2011, showing numbers of trap-sessions at each site (arrows to a–h) and numbers of X. laevis caught

Mentions: The habitats of X. laevis lie on an escarpment, mostly around 50 m a.s.l., north of Scunthorpe. The area is divided into two landscape types with an abrupt border along Lodge Lane (Fig. 2). Land use north of this road is agricultural, principally arable farmland and woodland; land to the south was previously dominated by a steelworks but has undergone major re-development as an industrial park. Parts of the steelworks site were heavily contaminated by chemical waste and re-development included removal of toxic soil. During our fieldwork, the ‘reclamation site’ had extensive spoil heaps and temporary ponds but the less-disturbed margins formed wetland habitats with reedbeds. The angling pond and ditch (Fig. 2a, b) had deep permanent water but most ponds on the reclamation site had shallow water, drying out during drought. There was no flowing water at any sites occupied by X. laevis and no direct connection with rivers. Water temperatures in the ditch, monitored during 2004–2008, were comparable with those recorded in Wales.Fig. 2


Extinction of an introduced warm-climate alien species, Xenopus laevis, by extreme weather events.

Tinsley RC, Stott LC, Viney ME, Mable BK, Tinsley MC - Biol. Invasions (2015)

Fieldwork area in North Lincolnshire, centred on 53°37′30″N, 0°40′14″W, north of Scunthorpe. Red triangles show localities of trapping in 2003–2010 where Xenopus laevis was never recorded (most sites trapped repeatedly in successive years). Data on the right of the map record habitats in which X. laevis occurred and results of surveying in 3 years, 2009–2011, showing numbers of trap-sessions at each site (arrows to a–h) and numbers of X. laevis caught
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4581400&req=5

Fig2: Fieldwork area in North Lincolnshire, centred on 53°37′30″N, 0°40′14″W, north of Scunthorpe. Red triangles show localities of trapping in 2003–2010 where Xenopus laevis was never recorded (most sites trapped repeatedly in successive years). Data on the right of the map record habitats in which X. laevis occurred and results of surveying in 3 years, 2009–2011, showing numbers of trap-sessions at each site (arrows to a–h) and numbers of X. laevis caught
Mentions: The habitats of X. laevis lie on an escarpment, mostly around 50 m a.s.l., north of Scunthorpe. The area is divided into two landscape types with an abrupt border along Lodge Lane (Fig. 2). Land use north of this road is agricultural, principally arable farmland and woodland; land to the south was previously dominated by a steelworks but has undergone major re-development as an industrial park. Parts of the steelworks site were heavily contaminated by chemical waste and re-development included removal of toxic soil. During our fieldwork, the ‘reclamation site’ had extensive spoil heaps and temporary ponds but the less-disturbed margins formed wetland habitats with reedbeds. The angling pond and ditch (Fig. 2a, b) had deep permanent water but most ponds on the reclamation site had shallow water, drying out during drought. There was no flowing water at any sites occupied by X. laevis and no direct connection with rivers. Water temperatures in the ditch, monitored during 2004–2008, were comparable with those recorded in Wales.Fig. 2

Bottom Line: In 2010, only a single individual was captured at each locality and further searching failed to record any others in repeated sampling up to 2014.We conclude that both populations are now extinct.The extinction of X. laevis in these areas indicates that even relatively long-established alien species remain vulnerable to rare extreme weather conditions.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ UK.

ABSTRACT

Invasive, non-native species represent a major threat to biodiversity worldwide. The African amphibian Xenopus laevis is widely regarded as an invasive species and a threat to local faunas. Populations originating at the Western Cape, South Africa, have been introduced on four continents, mostly in areas with a similar Mediterranean climate. Some introduced populations are also established in cooler environments where persistence for many decades suggests a capacity for long-term adaptation. In these cases, recent climate warming might enhance invasion ability, favouring range expansion, population growth and negative effects on native faunas. In the cool temperate UK, populations have been established for about 50 years in Wales and for an unknown period, probably >20 years, in England (Lincolnshire). Our field studies over 30 and 10 years, respectively, show that in favourable conditions there may be good recruitment, fast individual growth rates and large body size; maximum longevity exceeds 23 years. Nevertheless, areas of distribution remained limited, with numbers <500 in each population. In 2010, only a single individual was captured at each locality and further searching failed to record any others in repeated sampling up to 2014. We conclude that both populations are now extinct. The winters of 2009-2010 and 2010-2011 experienced extreme cold and drought (December 2010 was the coldest in 120 years and the third driest in 100 years). The extinction of X. laevis in these areas indicates that even relatively long-established alien species remain vulnerable to rare extreme weather conditions.

No MeSH data available.


Related in: MedlinePlus