World Congress of Malacology Antwerp ... - Unitas Malacologica

Pest snails in Australia: current management strategies and challenges for the future
Lush, Angela L. 1,2 ; Baker, G.H. 3
1. Current address: 4/24 Hill Ave, Cumberland Park, SA 5041 Australia,
Email: angelalush@gmail.com
2. SARDI, GPO Box 397 Adelaide 5001 Australia,
3. CSIRO Entomology P.O. Box 1700 Canberra ACT, Australia,
Email: geoff.baker@csiro.au
Several terrestrial snail species cause significant economic losses across a wide range of agricultural
industries in Australia. Losses can occur through a decrease in production, downgrading and/or
cleaning of produce, management, monitoring and inspection costs, and in some cases loss of export
markets. This paper reports on the strategies currently used to manage these problems, with a
particular focus on the broad-acre cropping and citrus industries.
Theba pisana, Cernuella virgata, Cochlicella acuta, and Prieoticella barbara are all pests of grain
crops in south-eastern Australia. A substantial research program has been undertaken over ~ 20 years
to provide management options to farmers. These options include chemical and cultural controls such
as burning, cabling, rolling and grain sieving, and more recently, a biological control agent,
Sarcophaga penicillata, has been introduced into Australia against C. acuta.
In the citrus industry, Cantareus aspersus and Microxeromagna armillata are responsible for the
majority of the economic losses. M. armillata has been found contaminating export fruit, which has
threatened market access of Australian fruit. Research has focused on understanding the basic
biology and ecology of M. armillata in addition to evaluating both chemical and cultural control
methods.
All of the aforementioned snails are introduced to Australia and, while the impacts of these species
on agricultural production are well documented, the influence of these species on the native flora and
fauna is not known. Understanding their impact and developing management strategies for these
pests in national parks and bushland is a substantial challenge for the future. Possible incursions of
other pest snails such as Achatina fulica and the aquatic Pomacea canaliculata are also of significant
concern and are discussed in this context.
Effects of a thermal effluent on the rocky intertidal molluscan assemblages
Maestre, Manuel J.; González, Alexandre R.; Espinosa, Free; Ruiz, Aurora; Gordillo, Ismael;
García-Gómez, Jose C.
Laboratorio de Biología Marina, Departamento de Fisiología y Zoología, Facultad de Biología,
Universidad de Sevilla, Avda. Reina Mercedes 6, 41012 Sevilla, Spain,
Email: Free@us.es.com
Thermal stress has been considered to be among the most important factors of organisms distribution
in the rocky intertidal zone. However, there are few studies that have been conducted in order to
evaluate the influence of thermal effluents on rocky intertidal communities.
Spatial-temporal distribution of rocky intertidal species affected by a thermal effluent was monitored
during one year. This study was carried out in Algeciras Bay (South of Spain). An increase on water
temperature of 10 ºC was found at the stations countinously exposed to the effluent. For molluscs, a
decrease on Shannon diversity index and species richness in the affected area was detected. The most
common species in the control area such as Patella caerulea, Cymbula safiana and Patella rustica,
were absent or scarce in the affected zone. However, the false limpet, Siphonaria pectinata, was the
most abundant mollusc, and its vertical distribution range was higher in the influenced area. On the
other hand, macrophyte communities also presented a lower species diversity and richness in the
stations closest to the thermal effluent. The seaweed Titanoderma pustulatum var. confine, almost
absent in the control area, was the dominant species in the thermal zone. The mollusc S. pectinata
was displaced by this algae in the area with the highest coverage.
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