Aquarium Industry Research Articles

The noncoding trnH-psbA spacer, as an effective DNA barcode for aquatic freshwater plants, reveals prohibited invasive species in aquarium trade in South Africa

The negative effects of invasive alien aquatic plants raise concern globally. These effects are predicted to increase in the future due to a rapid development in transport modes (air, terrestrial, and water) that facilitate connection between continents, difficulties inherent to identification of potentially problematic species, and for aquatic systems, insufficiently regulated aquarium and ornamental pond industries. In this study, we aimed to assist traditional species identification methods with genetic methods and provide ways of verifying the status of alien plants (invasive or non-invasive) sold in aquarium market in South Africa. To this end, the best DNA barcode for South Africa's freshwater plants was identified; a DNA barcode library was assembled and aquarium plants sold in Johannesburg (South Africa) were screened using this DNA barcode. We found that trnH-psbA was a reliable single DNA barcode for freshwater plant species in South Africa. We therefore assembled a trnH-psbA library on BOLD (Barcode Of Life Database) to assist in future identification of unknown or taxonomically doubtful freshwater alien plants in South Africa. Using this region to screen aquarium species, we found surprisingly that some prohibited aquatic invaders are already in circulation in the local aquarium trade, including Hydrilla verticillata (L.f.) Royle, Egeria densa Planch., Myriophyllum spicatum L., and Echinodorus cordifolius (L.) Griseb. This raises concern and calls for a strict regulation of species traded in aquarium industries to be implemented, as well as a need for public environmental education on the threat posed by invasive and potentially invasive plants for South Africa's natural aquatic ecosystems.

English

The aim of is study was to determine the growth performance of Mexican A. franciscana Yucatan Peninsula strains in different salinity tests. Four populations from different habitats were studied: Real de las Salinas (RSAL), Cancun (CAN), San Crisanto (CRIS) and Celestun (CEL). Nauplii from each population were inoculated in 200 L plastic tanks with 160 L of dissolved rock salt water at 40, 60, 80, 100 and 120 g L-1. The organisms were fed with Tetraselmis sp. and Pinnularia sp. microalgae (500 x 103 cells mL-1 water concentration) during the experiment period. Biometry length was measured to obtain absolute growth rate (AGR), instantaneous growth rate (IGR), and length gain (LG) values. Variance test (ANOVA) analysis was applied to determine the significant differences (P <0.05) between final length and growth rates of four populations. The total length range was 6.675-9.589 mm; AGR values ranged between 0.395 and 0.571 mm per day. IGR percentage range was 17.623-18.91% increase per day, and length range gain values were 6.277 to 9.130 mm. No significant difference was shown between 100 g L-1 salinity test and 120 gL-1 test, and then between CEL and RSAL strains.  The salinity variable showed high percentage (62 to 93%) in the salinity tests or significant strains (p<0.05). Yucatan Peninsula has several salt ponds with natural Artemia franciscana sources that can be used for aquaculture or aquarium industry. It is important to know growth performance of species in specific salinity concentration. This will help one to understand the adaptation of Artemia populations cultured in laboratory and also ensure better culture system management for producing biomass for use in aquaculture or aquarium industry or academic laboratory centers.   Key words: Artemia franciscana, survival, growth rates, length gain, salinity.

About the Cover.

Next article FreeAbout the CoverPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreCoverWhale sharks (Rhincodon typus) are the largest fish of any kind, and yet relatively little is known about their sensory ecology. Their sheer size makes them intractable subjects for experimental laboratory research, and manipulative studies in the field remain practically impossible. Developments in the public aquarium industry, however, mean that several collections of whale sharks are now available to the research community for investigations under at least quasicontrolled conditions.A compelling question about filter-feeding sharks is how they find suitable patches of food. Mechanisms suggested for the more typical predatory type of shark are less applicable in whale sharks, which feed on plankton. The surface suction-feeding illustrated in the cover image is the most common mode of feeding. During this behavior, the animal adopts a tail-down posture and the top jaw and, importantly, the nares protrude above the water surface where they may be exposed to volatilized chemical cues. Whale sharks have large olfactory lobes in the brain and well-developed nares, which suggests that chemical stimuli (smell or taste) may still play an important role.In seabirds, the volatile chemicals dimethylsulfide (DMS) and dimethylsulfoxide (DMSO) have been shown to initiate food-searching behavior through their positive correlation with plankton abundance and therefore forage fish abundance. In the experiment by A. Dove, described on pages 65–74, plumes of filtered krill extract and DMS were created in an aquarium to investigate whether these chemical cues may also operate in whale sharks. The Georgia Aquarium in Atlanta houses four whale sharks in a 6.3-million-gallon tank with thousands of other fish. The whale sharks responded most strongly to the krill juice mixture, but also showed significant behavioral responses to DMS alone, which suggests that this chemical may play a role in their feeding ecology. With a diverse known diet, however, it is unlikely that a single chemical mediates all feeding responses in whale sharks, and so the quest for deeper understanding of feeding behavior in the world's biggest fish continues.Credits: Photo, Alistair Dove, Georgia Aquarium; layout, Beth Liles, Marine Biological Laboratory. Next article DetailsFiguresReferencesCited by The Biological Bulletin Volume 228, Number 1February 2015 Published in association with the Marine Biological Laboratory Article DOIhttps://doi.org/10.1086/BBLv228n1cover © 2015 by Marine Biological Laboratory. All rights reserved.PDF download Crossref reports no articles citing this article.

Hydrellia fly parasitic wasp Trichopria columbiana Ashmead (Insecta: Hymenoptera: Diapriidae)

Trichopria columbiana is a parasitoid of Hydrellia fly species. Depending on the ecological role of the host species, it can have a positive or negative effect on biological control. Some Hydrellia species feed on the invasive aquatic weed hydrilla. After its introduction into the U.S. by the aquarium industry in the 1950s (Langeland 1996), various control methods, including biological control, were developed and used to manage infestations. Classical biological control studies were initiated in the 1970s, which led to the release of four insects in the U.S., two of which were the leaf-mining ephydrid flies, Hydrellia pakistanae and Hydrellia balciunasi. Despite successful establishment and range expansion of the Asian hydrilla leaf mining fly, Hydrellia pakistanae, population levels of the insect and associated plant damage have remained low. One of the potentially limiting biotic factors is parasitism by the native endoparasitic wasp Trichopria columbiana. This 6-page fact sheet was written by Byron R. Coon, Nathan E. Harms, Michael J. Grodowitz, Emma N.I. Weeks, and James P. Cuda, and published by the UF Department of Entomology and Nematology, June 2014. EENY597/IN1040: Hydrellia Fly Parasitic Wasp Trichopria columbiana Ashmead (Insecta: Hymenoptera: Diapriidae) (ufl.edu)

Presence of prohibited fishes in the Brazilian aquarium trade: effectiveness of laws, management options and future prospects

Regulations applied to the importation of ornamental nonnative fishes vary from country to country. In the U.S., it is possible to import many species of aquaria fish with the exception of the snakehead Channa and Parachanna spp. (Courtenay and Williams, 2004). In Brazil, at the end of the 1990s, the National Environmental Crimes Act No. 9605 of 1998 was passed to regulate the management of non-native species. This act emphasizes the trade regulation of nonnative aquatic species through vectors such as fish importation and the aquarium industry (Sampaio and Ostrensky, 2013). To reduce the likelihood of future invasions in Brazil, certain specific aquarium species were placed on the Federal Normative Instructions No. 202 and No. 203 of 2008 for saltwater and freshwater fish species, respectively (Table 1). These laws were passed by the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA), which determined the import of these non-native fishes into the Brazilian aquarium trade as illegal due to: (i) irrelevance to the hobby (Lutjanus sebae, Pangasianodon hypophthalmus, Channa argus, Channa striata, Clarias batrachus, Osphronemus gourami, Trichopodus pectoralis); (ii) aggressive behavior (C. argus, Channa lucius, Channa micropeltes, C. striata, C. batrachus); and (iii) history of invasions in other countries (Centropyge flavissima, T. pectoralis, O. gourami, C. micropeltes, C. striata, C. batrachus) (Brasil, 2008a,b). Despite the Brazilian government ruling the importation of the above nonnative species as illegal, the efficacy of the regulatory policies has never been evaluated. This paper examines the ban effectiveness on the importation of ten non-native fish species by aquarium stores in Brazil for the first time.

DNA barcoding of commercially important catfishes in the Philippines

Many species of catfish are important resources for human consumption, for sport fishing and for use in aquarium industry. In the Philippines, some species are cultivated and some are caught in the wild for food and a few introduced species have become invasive. In this study, DNA barcoding using the mitochondrial cytochrome c oxidase I (COI) gene was done on commercially and economically important Philippine catfishes. A total of 75 specimens belonging to 11 species and 5 families were DNA barcoded. The genetic distances were computed and Neighbor-Joining (NJ) trees were constructed based on the Kimura 2-Parameter (K2P) method. The average K2P distances within species, genus, family and order were 0.2, 8.2, 12.7 and 21.9%, respectively. COI sequences clustered according to their species designation for 7 of the 11 catfishes. DNA barcoding was not able to discriminate between Arius dispar and A. manillensis and between Pterygoplichthys disjunctivus and P. pardalis. The morphological characters that are used to distinguish between these species do not complement molecular identification through DNA barcoding. DNA barcoding also showed that Clarias batrachus from the Philippines is different from the species found in India and Thailand, which supports earlier suggestions based on morphology that those found in India should be designated as C. magur and those in mainland Southeast Asia as C. aff. batrachus “Indochina”. This study has shown that DNA barcoding can be used for species delineation and for tagging some species for further taxonomic investigation, which has implications on proper management and conservation strategies.

Aquarium Industry Threatens Biodiversity

The aquarium industry is a major source of aquatic invasions, especially in terms of the number of species and potential sites of species release (1, 2). The introduction of species to foreign ecosystems occurs through intentional release of adults from aquaria into the environment, accidental release from breeding facilities (common in areas where the captive stocks are raised in outdoor farms), and unnoticed release of juveniles in discarded water (1). Regulatory and legal mechanisms that rely on accurate species-specific data are critical to preventing biological invasions and mitigating the consequences of those that occur (3).

Regeneration as a novel method to culture marine ornamental sabellids

Collection of live invertebrates from coral reefs has increased dramatically over the past two decades in response to the growing marine aquarium industry, and currently, more than 500 species (excluding corals) are traded globally. Aquaculture of ornamental species is deemed a priority solution in mitigating the effects of wild collection but expanding the range of species is limited by bottlenecks at key life history stages. A novel culture method for ornamental sabellids, which utilises their outstanding regenerative capacity in a process similar to coral ‘fragging’, has been developed and survivorship after regenerative development assessed. Sabella pavonina, a temperate species found around the UK, was used as a model to develop a culture technique which was subsequently transferred to a tropical species of Sabellastarte. Survivorship of S. pavonina was high (≥80%) in individuals which had been cut into as many as eight fragments and all fragments completed regenerative development within a four week period. Sabellastarte species exhibited ≥75% survivorship when cut into just two fragments, but higher mortality was recorded with increasing number of cuts, with only 20% of fragments from individuals cut into eighths surviving the duration of the experiment. Both test species were capable of regenerating cephalically and caudally within a four week period. Caudal regeneration involved the healing of the cut surface, reconstruction of the pygidium and subsequent segment addition, while cephalic regeneration was a more complex process of wound healing, reconstruction of a new mouth and the development of the branchial crown structure. It is concluded that differences in survivorship between S. pavonina and Sabellastarte sp. could be attributed to either infection due to sub-optimal water quality in the test tanks, or species-specific differences in the area of wound size in relation to the length of the fragment. Optimisation of survivorship and the speed of regenerative growth could be improved with the enhancement of the culture system.

Comparative performance of light emitting plasma (LEP) and light emitting diode (LED) in ex situ aquaculture of scleractinian corals

Ex situ aquaculture of scleractinian corals is considered as a sustainable solution to fulfill the growing demand of these highly priced organisms by the marine aquarium industry. The economic feasibility of ex situ coral aquaculture is strongly dependent on the trade-offs achieved between coral production and energy costs, namely those directly resulting from the need to employ artificial lighting systems. In the present study, we hypothesize that light spectrum can influence the growth performance of cultured scleractinian corals when these are exposed to identical photosynthetically active radiation (PAR) intensities. To test our hypothesis we evaluated the effect of contrasting light spectra delivering an identical PAR of 250±10μmol quanta m−2s−1emitted by T5 fluorescent lamps (used as a control treatment), Light Emitting Plasma (LEP) and Light Emitting Diode (LED) on the photobiology, growth, and protein concentration of two commercially important scleractinian corals: Acropora formosa and Stylophora pistillata. Replicated coral fragments of both species were exposed to the three types of illumination for a period of 5months after which the following features were determined: maximum quantum yield of PSII (Fv/Fm) (monitored non-intrusively through Pulse Amplitude Modulation fluorometry, PAM), chlorophyll a content (also determined non-destructively by using the spectral reflectance index Normalized Difference Vegetation Index, NDVI), growth and protein content. Coral fragments of both species cultured under LEP lighting, presented significantly higher values of Fv/Fm when compared intraspecifically with coral fragments cultured with T5 or LED lighting. Fragments of S. pistillata cultured under LEP illumination presented significantly higher NDVI values than fragments grown with T5 or LED. No significant differences were found on the protein concentration of A. formosa under different light treatments, while fragments of S. pistillata grown with LED illumination presented a significantly higher concentration of protein than those cultured with T5 or LEP illumination. Both LED and LEP technologies have shown to be interesting alternatives to provide artificial lighting for coral aquaculture ex situ, with the blue light spectrum of LED promoting high growth performances for both coral species and a lower energetic cost per m2 of production area (0.71€m−2day−1 for T5, 0.38€m−2day−1 for LEP, and 0.28€m−2day−1 for LED).

Global challenges in freshwater‐fish conservation related to public aquariums and the aquarium industry

Fresh waters in lakes, ponds, rivers, estuaries and wetlands are only 0·3% of available global surface water yet support 47–53% (> 15 000) of all extant fish species. Freshwater fishes are globally valuable yet threatened everywhere through overfishing, pollution, habitat loss, damming, alien invasive species and climate change. Hence, they are in dire need of effective and sustained conservation action, including through zoo and aquarium programmes in the wild and ex situ. To address these challenges, zoo and aquarium staff need to be familiar with the substantial issues, develop greater expertise, and become better integrated in wider regional and global initiatives in freshwater‐fish conservation and sustainability. Resolving diverse issues requires knowledge of the many different values in the conservation of freshwater fishes, including sustainable commercial fisheries and the aquarium trade. It is necessary to assess and mitigate threats to fish survival through research and monitoring. An improved conservation‐orientated science of threatened fish species is also needed in terms of taxonomy and biology. From this, the implementation and dissemination of appropriate conservation policies, strategies and legislation can be developed. All these factors enable direct practical action for fish conservation, in conjunction with improved zoo education, training and public communication. Finally, review and evaluation of the efficacy of various conservation actions must be carried out in order to plan future undertakings.

Record Body Size for the Red Lionfish, Pterois Volitans (Scorpaeniformes), in the Southern Gulf of Mexico

Non-native species are those that have been transported, via human actions, from one continent and introduced into another (Lockwood et al. 2007). In the 1980s, red lionfish, Pterois volitans (Linnaeus, 1758), traded in the US aquarium industry from the Pacific Ocean, was introduced into the coral reefs off Florida's coast by aquarium hobbyists (Morris and Whitfield 2009). It is unknown how this introduction occurred, but after more than 20 years the red lionfish population is widespread, occupying a large portion of the Western Atlantic (Schofield 2010) where it represents a threat to the marine ecosystem (Green et al. 2012). The population appears impossible to eradicate since it can live to depths up to 100 m, where individuals consume native small crustaceans and reef fish (Morris and Akins 2009, Green et al. 2012).

Breeding and Life Cycle of Neocaridina denticulata sinensis (Kemp, 1918)

Neocaridina denticulata sinensis (Kemp, 1918) or also known as red cherry shrimp (RCS) became popular in aquarium industry since its first introduction in 2003 until now. Little is known of this particular species since documented report is very scarce. Thus, this study was conducted to gather some information on its breeding behavior and life cycle until first maturity in laboratory condition. Fertilized eggs were found to be oval in shape with color varies from greenish to yellowish. The egg size was comparatively large, with an average diameter of 1.19 mm. Embryonic development of N. d. sinensis lasted for 15 days at 27°C. Newly hatched larvae look like a miniature version of the adult with an average total length of 2.3 mm. A female can produced about 21-51 larvae per hatching. Larger females produced more larvae. It takes 60 days for larvae to reach juvenile stage, where male and female were still undifferentiated. Juveniles become adults 15 days later. Females were obvious with the presence of orange colored ovary at the cephalothorax region. Within one to three days, these males and females are ready to spawn. During this study, N. d. sinensis cultured in freshwater were found to be susceptible to clitellate annelid (Holtodrilus sp.). Culture of this species in slightly saline condition between 5-10 ppt was an effective treatment for this annelid.

Comportamiento reproductivo del pez Opistognathus rosenblatti (Perciformes: Opistognathidae) en cautiverio

Reproductive behavior of Opistognathus rosenblatti (Perciformes: Opistognathidae) in captivity. The Blue Spotted Jawfish O. rosenblatti, is an endemic species from the Gulf of California, included in the local list of protected species. With few biological reports, this species is appreciated in the aquarium industry due to its coloration and digging behaviour, and has a considerable value. With the aim to generate valuable biological information, eight fishes were caught at Loreto Natural Marine Protected Area. Captured fishes were juveniles, and just three of them were kept in an aquarium conditioned with gravel, pieces of shells and coral as substrata. Temperature and photoperiod conditions were stable, and they were supplied with a variety of live and inert feeds. Fishes reached maturity in eight months, according to literature reports, displaying mature male courtship coloration and upward movements in the water column. Fishes spawned several times over more than two years in captivity. Presences of egg masses, or some evidence of egg shell or larvae, were registered in 50 occasions. Male took care of eggs in his shelter, but never in his mouth. Egg masses had an average of 3 592 eggs, with a hatching rate close to 99%. Eggs were apparently rounded having three diameter measurements with significant differences (1.17mm mean higher diameter, SD=0.054; 1.13mm mean lower diameter, 0.058; 0.99mm mean height, 0.045; n=125). Most of corion eggs had four, rarely six filaments; with a single oil drop (0.30mm mean diameter, 0.021, n=59). Incubation lasted 10.4 days (9-14), depending on water temperature (21.0-25.3°C). Egg hatching occurred after darkness, emerging newly hatched larvae of 4.51mm mean notochord length (0.082, n=30), with reserves exhausted, eyes pigmented and mouth opened, ready to eat. This study represents the first report on this species courtship displaying, spawning and some basic characteristics of eggs masses and larvae in captivity. Also, their flexibility and adaptability of individual behaviour to particular environment conditions, lead to consider worth their commercial culture, as already occur with other species of this family.

Species Management Benchmarking: Outcomes Over Outputs in a Changing Operating Environment

Species management has been utilized by the zoo and aquarium industry, since the mid-1990s, to ensure the ongoing genetic and demographic viability of populations, which can be difficult to maintain in the ever-changing operating environments of zoos. In 2009, the Zoo and Aquarium Association Australasia reviewed their species management services, focusing on addressing issues that had arisen as a result of the managed programs maturing and operating environments evolving. In summary, the project examined resourcing, policies, processes, and species to be managed. As a result, a benchmarking tool was developed (Health Check Report, HCR), which evaluated the programs against a set of broad criteria. A comparison of managed programs (n = 98), between 2008 and 2011, was undertaken to ascertain the tool's effectiveness. There was a marked decrease in programs that were designated as weak (37 down to 13); and an increase in excellent programs (24 up to 49) between the 2 years. Further, there were significant improvements in the administration benchmarking area (submission of reports, captive management plan development) across a number of taxon advisory groups. This HCR comparison showed that a benchmarking tool enables a program's performance to be quickly assessed and any remedial measures applied. The increases observed in program health were mainly due to increased management goals being attained. The HCR will be an ongoing program, as the management of the programs increases and goals are achieved, criteria will be refined to better highlight ongoing issues and ways in which these can be resolved.

Opportunities for Public Aquariums to Increase the Sustainability of the Aquatic Animal Trade

The global aquatic pet trade encompasses a wide diversity of freshwater and marine organisms. While relying on a continual supply of healthy, vibrant aquatic animals, few sustainability initiatives exist within this sector. Public aquariums overlap this industry by acquiring many of the same species through the same sources. End users are also similar, as many aquarium visitors are home aquarists. Here we posit that this overlap with the pet trade gives aquariums significant opportunity to increase the sustainability of the trade in aquarium fishes and invertebrates. Improving the sustainability ethos and practices of the aquatic pet trade can carry a conservation benefit in terms of less waste, and protection of intact functioning ecosystems, at the same time as maintaining its economic and educational benefits and impacts. The relationship would also move forward the goal of public aquariums to advance aquatic conservation in a broad sense. For example, many public aquariums in North America have been instrumental in working with the seafood industry to enact positive change toward increased sustainability. The actions include being good consumers themselves, providing technical knowledge, and providing educational and outreach opportunities. These same opportunities exist for public aquariums to partner with the ornamental fish trade, which will serve to improve business, create new, more ethical and more dependable sources of aquatic animals for public aquariums, and perhaps most important, possibly transform the home aquarium industry from a threat, into a positive force for aquatic conservation.

Effectiveness of the California State Ban on the Sale of Caulerpa Species in Aquarium Retail Stores in Southern California

The invasion of the aquarium strain of the green alga Caulerpa taxifolia and subsequent alteration of community structure in the Mediterranean Sea raised awareness of the potential for non-native seaweeds to impact coastal communities. An introduction of C. taxifolia in southern California in 2000, presumably from the release of aquarium specimens, cost ~$7 million for eradication efforts. Besides C. taxifolia, other Caulerpa species being sold for aquarium use also may have the potential to invade southern Californian and U.S. waters. Surveys of the availability of Caulerpa species in southern California aquarium retail stores in 2000-2001 revealed that 26 of 50 stores sold at least one Caulerpa species (52 %) with seven stores selling C. taxifolia. In late 2001, California imposed a ban on the importation, sale, or possession of nine Caulerpa species; the City of San Diego expanded these regulations to include the entire genus. To determine the effectiveness of the California ban, we resurveyed Caulerpa availability at 43 of the 50 previously sampled retail stores in southern California in ~2006, ~4 years following the ban. Of the 43 stores, 23 sold Caulerpa (53 %) with four stores selling C. taxifolia. A χ(2) test of frequency of availability before and after the California ban suggests that the ban has not been effective and that the aquarium trade continues to represent a potential vector for distributing Caulerpa specimens, including C. taxifolia. This study underscores the need for increased enforcement and outreach programs to increase awareness among the aquarium industry and aquarium hobbyists.

La acuariofilia de especies ornamentales marinas: un mercado de retos y oportunidades

The aquariums industry is a trade that is expanding. Although there is no accurate information regarding the figures of the aquarium industry in the international scenario, it is estimated to generate revenues over US$ 300 million with an annual growth rate of 14%. Approximately US$ 28 to 44 million of this amount is generated by the ornamental marine fish trade. However, the trade in marine species has aroused controversy regarding the extraction of almost all traded marine organisms from wild populations and, in many cases, illegally. This paper presents a review that includes: the ornamental marine fishkeeping history, the species of commercial importance, the international trade scenario, risks of the aquarium industry, conservation strategies, and the current situation of this trade in Mexico. The last section focuses on describing the development and market prospects of the marine aquarium trade. Additionally, some initiatives from academic and private institutions aimed at developing sustainable aquaculture on ornamental marine fish species of commercial importance in Mexico are provided.

Managing the Marine Aquarium Trade: Revealing the Data Gaps Using Ornamental Polychaetes

The marine aquarium industry has great potential to generate jobs in low-income coastal communities creating incentives for the maintenance of a healthy coral reef, if effectively managed. In the absence of current monitoring or legislation to govern the trade, baseline information regarding the species, number and source location of animals traded is missing despite being critical for its successful management and sustainability. An industry assessment to establish the number and provenance of species of ornamental polychaetes (sabellids and serpulids) traded was undertaken across UK wholesalers and retailers. Six geographical regions exporting fan worms were identified. Singapore contributed the highest percentage of imports, but of only one worm “type” whereas Bali, the second largest source, supplied five different worm “types”. Over 50% of UK retailers were supplied by one wholesaler while the remainder were stocked by a mixture of one other wholesaler and/or direct imports from the source country. We estimate that up to 18,500 ornamental polychaetes (16,980 sabellids and 1,018 serpulids) are sold annually in the UK revealing a drastic underestimation of currently accepted trade figures. Incorrect identification (based on exporting region or visual characteristics) of traded animals exacerbates the inaccuracy in market quantification, although identification of preserved sabellids using published keys proved just as inconclusive with high within-species variability and the potential for new or cryptic species. A re-description of the polychaete groups traded using a combination of molecular and morphological techniques is necessary for effective identification and market quantification. This study provides the first assessment of ornamental polychaetes but more importantly highlights the issues surrounding the collection of baseline information necessary to manage the aquarium trade. We recommend that future management should be community based and site-specific with financial and educational support from NGOs, local governments and industry members.

Coral diseases in aquaria and in nature

Many reef coral diseases have been described affecting corals in the wild, several of which have been associated with causal agents based on experimental inoculation and testing of Koch's postulates. In the aquarium industry, many coral diseases and pathologies are known from the grey literature but as yet these have not been systematically described and the relationship to known diseases in the wild is difficult to determine. There is therefore scope to aid the maintenance and husbandry of corals in aquaria by informing the field of the scientifically described wild diseases, if these can be reliably related. Conversely, since the main driver to identifying coral diseases in aquaria is to select an effective treatment, the lessons learnt by aquarists on which treatments work with particular syndromes provides invaluable evidence for determining the causal agents. Such treatments are not commonly sought by scientists working in the natural environment due the cost and potential environmental impacts of the treatments. Here we review both wild and aquarium diseases and attempt to relate the two. Many important aquarium diseases could not be reconciled to those in the wild. In one case, however, namely that of the ciliateHelicostomasp. as a causal agent of brown jelly syndrome in aquarium corals, there may be similarities with pathogenic agents of the wild coral diseases, such as white syndrome and brown band syndrome. We propose thatHelicostomais actually a misnomer, but improved understanding of this pathogen and others could benefit both fields. Improved practices in aquarium maintenance and husbandry would also benefit natural environments by reducing the scale of wild harvest and improving the potential for coral culture, both for the aquarium industry and for rehabilitation programmes.

Prospects for the Biological Control of Submerged Macrophytes in South Africa

Historically, biological control efforts against aquatic plants in South Africa have focused on floating species, and as a result, there has been a dearth of research into the invasion and control of submerged macrophytes. With numerous submerged invasive species already established in South Africa, thriving horticultural and aquarium industries, nutrient-rich water systems, and a limited knowledge of the drivers of invasions of submerged macrophytes, South Africa is highly vulnerable to a second phase of aquatic plant problems. Experience gained in the U.S.A. on biological control against submerged weeds, such as hydrilla, Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae) and spiked/Eurasian watermilfoil, Myriophyllum spicatum L. (Haloragaceae), have provided South African researchers with the necessary foundation to initiate programmes against these weeds. Research in South Africa is currently focused on pre-release studies on the biological control of H. verticillata, using an undescribed fly, Hydrellia sp. (Diptera: Ephydridae) and a weevil, Bagous hydrillae O'Brien (Coleoptera: Curculionidae); and on M. spicatum using a North American weevil, Euhrychiopsis lecontei Dietz (Coleoptera: Curculionidae). Feasibility studies into biological control of some incipient submerged weeds are also being conducted, including Brazilian water weed, Egeria densa Planch. (Hydrocharitaceae), Canadian water weed, Elodea canadensis Mitch. (Hydrocharitaceae) and cabomba, Cabomba caroliniana A.Gray (Cabombaceae). Progress with, and potential constraints that may limit these programmes, are discussed.