Australia - Introduction

AbstractThe Old World screw-worm fly, Chrysomya bezziana Villeneuve, occurs in Africa, the Middle East, Malaysia, Indonesia and Papua New Guinea, but it is not found in Australia. Introduction into Australia from any of these source areas would threaten the viability of much of the grazing industry in the northern part of the continent. Proposed control by the sterile insect release method (SIRM) would be compromised by the existence of sibling species within C. bezziana. This study examines the degree of genetic differentiation throughout the extensive range of the fly to assess if the degree of geographic differentiation indicates the existence of sibling species and, allows identification of the source of any introduced flies. Electrophoretic analysis of 23 loci from samples collected in southern Africa, the Middle East, Malaysia, Indonesia, and Papua New Guinea revealed 11 polymorphic loci. Overall, populations show remarkably little divergence given the geographic distribution of sample sites. None of the populations sampled were fixed for alternative electromorphs. There is no evidence from this study for the presence of sibling species within C. bezziana.

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The second Korean nuclear crisis and Australia: Introduction

Australian Journal Of International Affairs ◽

10.1080/10357710301749 ◽

2003 ◽

Vol 57 (2) ◽

pp. 259-260

Keyword(s):

Australia Introduction ◽

Nuclear Crisis

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The distribution of Carrichtera annua in Australia: introduction, spread and probable limits

The Rangeland Journal ◽

10.1071/rj10001 ◽

2011 ◽

Vol 33 (1) ◽

pp. 23 ◽

Cited By ~ 5

Author(s):

Julia Cooke ◽

R. H. Groves ◽

Julian Ash

Keyword(s):

Abiotic Factors ◽

Calcareous Soils ◽

South Australia ◽

Lag Phase ◽

Stable Range ◽

Long Distance ◽

Australia Introduction ◽

History Of ◽

The 1960S ◽

Accidental Introduction

Carrichtera annua (L.) DC. (Brassicaceae) or Ward’s Weed, a major weed of semi-arid rangelands of southern Australia, has been collected widely since its introduction early in the 20th century. Collated records were used to suggest a single site of accidental introduction in South Australia, evidence of a lag phase of ~30 years (probably due to edaphic restrictions) before rapid spread, involving infrequent long-distance human-aided dispersal across southern Australia and a relatively stable range since the 1960s. Climate and soil analyses suggest that abiotic factors limit the distribution of C. annua, with the species being restricted to areas with winter-dominated rainfall and calcareous soils. Documentation of the history of a successful invasion, including the spread and probable limits of the current distribution of a species, is important for managing invasions. This study also highlights that a single, accidental introduction can result in a long-lasting, widespread problematic weed.

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