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News 1N Editorial The principal role of this journal is to pro- IPM. The risk is that biotechnologies will plant resistance provided by transgenic vide information on scientific research in ultimately fail if insufficient attention is crops were wasted through a failure to biological control. Through its News, paid to ecological processes such as resist- integrate their use with biological control however, it has focused on some impor- ance development, non-target effects and and other components to make locally sus- tant issues in the periphery of biological the dynamics of pest complexes as we tainable IPM systems. In this issue, we control, but of considerable relevance to it. move from a pesticide-based to a biotech- announce the creation of a new interna- One of these has been biotechnology. Bio- nology-based control system for just one tional working group to examine the technologies for plant protection, epitomized pest species. integration of biotechnology with biolog- by Bt crops, will particularly influence ical control in IPM. We hope that biological control through their impact on Biological control shares with plant resist- biological control practitioners will the development of regulatory procedures, ance (and hence with these biotechnologies) respond through this and other activities to their effect on the production and use of the desirable feature that it can be self- the challenge to study, understand and biopesticides, and through the way they renewing and potentially free to the share the opportunities and threats which are incorporated into IPM systems. One farmer. In principle, and politics aside, this transgenic crops pose to improving sus- current concern is that these technologies allows these two key components of IPM tainable pest management. will, indeed, not be treated as components to benefit both the wealthy and the poor. It of IPM at all, but as hi-tech alternatives to would be a great pity if the new capacity in General News Aliens Make Waves impact studies made, and it is then tacitly predation and/or competition. The Wash- accepted that nothing can be done. But ington Department of Fish and Wildlife Biocontrollers may soon be heading for there are signs that the tide is on the turn. has enacted emergency regulations in a the beach. Invaders from across the sea are From the Pacific Coast of the USA, probably futile attempt to try and halt its giving marine biologists around the world through the Mediterranean, to Australia, onward spread to Puget Sound. abadfitofmal-de-mer as they see native marine biologists are seriously consid- A native of the Atlantic coasts of Europe fruits-de-mer put at risk by alien species. ering the introduction of exotic natural and northern Africa, in its home range the The marine environment offers fewer bar- enemies for a range of pests. green crab is found in protected rocky, riers than found on land to the regional Barnacle May Fit the Bill sandy and tidal habitats. It feeds vora- spread of invasive organisms. Ocean cur- ciously, often on bivalve molluscs and rents speed dispersal within a region, but The European green crab, Carcinus particularly mussels, and has a significant help from the planet's most invasive spe- maenas, was introduced to the eastern sea- impact on populations of these. Prelimi- cies – Homo sapiens – is necessary to board of the USA some 200 years ago and nary results suggest that it has a similar transfer species to new regions where they is frequently held responsible for deci- and perhaps more substantial impact in its may become noxious pests. There are sev- mating the soft-shell clam industry in the introduced range: dramatic declines in eral important vectors – the aquarium 1950s in Maine and the Canadian Mari- other crab and bivalve species have been industry, aquaculture, the bait industry, times. It was first recorded on the West measured in California and Tasmania. In and shipping. In any one week, 10,000 or Coast from San Francisco Bay in 1989/90, the summer of 1996, Carcinus' predatory more species may be transported around and since then has moved northwards at an activities led to the loss of almost one-half the world attached to the hulls or in the sea alarming rate of well over 100 miles (160 of the Manila clam stock under culture in chests and ballast water of ships. This km) a year, and this, says Kuris, represents benthic mesh bags in one shellfish opera- latter source has been identified as one of the fastest marine expansion of any marine tion in a central Californian bay. Native the major culprits of alien marine intro- animal, anywhere, ever. It escaped from shore crab population declines are greater ductions – an average-sized tanker carries San Francisco Bay in 1994, reaching than 90% in some areas. an estimated 244 million large planktonic Bodega and Tomales bays, about 50 miles individuals (7000 per cubic metre) during (80 km) north of there. Then it exploded The crab has many of the classical periods of high plankton productivity. into Humboldt Bay in 1995, Cocos Bay in attributes of a successful invasive species. Although notable successes have been 1996, and Willapa Bay and Grays Harbor Kuris identifies its outstanding dispersal recorded for biological control in fresh- in Washington State in 1998. It is consid- and recruitment abilities as key to its suc- water systems, it has never before been ered to be a serious threat to the fisheries cess as an invader. It also has high attempted in a marine environment. and mariculture industry of the Pacific reproductive and growth rates, and wide Armand Kuris from the University of Cal- Northwest (with an estimated value of environmental tolerances. It is omnivo- ifornia at Santa Barbara argues that there US$45 million/year) and wildlife. Native rous and opportunistic, capable of learning has been a fatalistic attitude to marine birds and Dungeness crabs have been sin- and improving its prey handling skills. Its pests: alien species are detected and gled out as particularly at risk, from body and claws are well armoured, ena- Are we on your mailing list? BiocontrolNews and Information is always pleased to receive news of research, conferences, new products or patents, changes in personnel, collaborative agreements or any other information of interest to other readers. If your organization sends out press releases or newsletters, please let us have a copy. In addition, the editors welcome proposals for review topics. 2N BiocontrolNews and Information 1999 Vol. 20 No. 1 bling it to crush bivalves unavailable to aquarium: dense mats of giant stolons pro- so the seaslugs can produce their own food other crabs, and potentially increase its duce tangled masses of fronds up to 80 cm by photosynthesis. resistance to predation. In some areas it in height. Not only is it vigorous and inva- has relatively novel predatory abilities as it sive, but it colonizes the seabed from the The potential of seaslugs for controlling is larger and more agile than native crabs. shoreline down to 100 m depth, and can Caulerpa was originally suggested to These attributes make it, according to give 100% cover of the seabed down to 50 Alexandre Meinesz of the University of Kuris, a worst-type case of introduced m. It thrives in both clean and polluted Nice–Sophia Antipolis in France by Kerry Clark of the Florida Institute of Tech- pest. water, in exposed and sheltered sites, nology in Melbourne, who died in January grows on rocks, sand and silt, clogs the A study that compared populations of this year. There are three sacoglossan sea- native seagrass beds, and survives far green crabs from Europe with those from slugs native to the Mediterranean that feed colder temperatures than the conventional all areas of the world where the green crab on the local Caulerpa prolifera. However, form would survive. Another peculiarity: has been introduced, found that the intro- although they have begun to eat C. taxi- unlike the conventional form, no sexual duced populations seemed to be folia also,theymaynotbeeffectivein reproduction has been observed in the experiencing a release from their natural controlling it because of their reproductive Mediterranean weed. Instead it reproduces enemies. Green crabs in introduced popu- characteristics. Their eggs hatch into vegetatively, spreading by fragmentation. lations lacked any parasitism that had planktonic larvae that disperse widely These oddities of growth and form have direct effects on reproduction, and they from where they hatch. However, led some to speculate that it is a particular reached larger sizes and lost fewer limbs Meinesz’ interest was rekindled when he strain, while recent evidence from genetic than their European counterparts. received a shipment from the Caribbean of studies supports the view that it is an C. taxifolia that had been partially eaten in aquarium escapee, a clone of a single A team led by Kuris and Kevin Lafferty is transit by individuals of two seaslug spe- plant. assessing the prospects for introducing a cies, Oxynoe azuropunctata and Elysia rhizocephalan barnacle, Sacculina car- subornata. Two attributes of these tropical But whatever its true identity, the weed is cini, that parasitizes C. maenas in Europe, sacoglossan seaslugs are particularly sig- having a serious impact as it spreads its native range. This species blocks nificant: they reproduce fast (1000 eggs/ relentlessly through the Mediterranean, its moulting of its host, and acts as a parasitic week) and the planktonic larval stage is castrator, causing female sterility and fem- thick carpet smothering native algae. It absent. inizing the males. However, genetic work contains toxins (the terpene caulerpenyn) has shown that putative S. carcini from andisnotfedonbyfishorinvertebrates. Give the climatic differences, it is unlikely several portunid crab genera in Europe Firstspottedcoveringanareaofnomore that the Caribbean slugs would be able to cannot be distinguished genetically, than a square metre in front of the museum survive the Mediterranean winter, yet this (while they are genetically distinct from aquarium in Monaco in 1984, by 1990 it could be turned to initial advantage.