Reef Ramblings

The International trade in live corals may help preserve wild  corals and coral reefs.

In the wake of the recent proposal by the National Ocean and Atmospheric Administration (NOAA) to list 66 species of coral under the Endangered Species Act (ESA) and Sea Shepherd adding the elimination of the aquarium hobby to its aims, it is heartening to see a study published this week showing that the reef aquarium trade may be having a positive influence on coral reefs.

The study, ‘Long-term trends of coral imports into the United States indicate future opportunities for ecosystem and societal benefits’ by Rhyne, Tlusty, and Kaufman, was published in the December issue of the journal Conservation Letters. The team of researchers from Roger Williams University, Boston University, Conservation International, and the New England Aquarium, suggest that the trade in live corals may help to preserve wild corals and coral reef ecosystems.

Whereas trade in corals was once primarily a trade of dried skeletons as curios, it is now concentrated on supplying live corals for the reef aquarium hobby in a trade that is continually evolving, with the introduction of species new to the hobby.

The authors analysed 21 years of US import data, finding that the coral trade had increased over 8% per year between 1990 until the mid-2000s, and has since reduced by 9% annually. The timing of the peak and decline varies between species, and is a result of the rising popularity of the reef aquarium hobby, global financial issues, and an increase in domestic aquaculture production, with the decrease mostly owing to the current economic climate.

The live coral trade is viewed by some critics as a threat to the high biodiversity ecosystems that make up the coral reefs, however, supplying the aquarium trade with locally cultivated corals offers opportunities for reef conservation, provides sustainable economic benefits to coastal communities, along with an incentive to protect the reefs from which the mother colonies are obtained.

Recent changes in the trade of live corals for the reef aquarium hobby are resulting in new opportunities for conservation. “The trade has moved from a wild harvest to mariculture production, a change sparked by long-term efforts to produce a sustainable income to small island countries such as the Solomon Islands and also by the government of Indonesia,” says Andrew Rhyne, lead-author and Roger Williams University assistant professor of marine biology and research scientist at the New England Aquarium. This shift from a wild fishery to a mariculture product poses new opportunities and challenges for conservationists.

The rapid evolution of the trade with new species waxing and waning in value makes effective management difficult. “New species in the live coral trade initially command high prices, but as they become common the price drops with feedback effects to the trade,” said Les Kaufman, Boston University professor of biology and research fellow at Conservation International.

“The live coral trade offers opportunities for coral reef ecosystem conservation and sustainable economic benefits to coastal communities,” says Rhyne. Michael Tlusty of the New England Aquarium, adding that “the realization of these externalities will require effective data tracking.”

Coral reefs are subject to numerous anthropogenic threats including the global threat of warming oceans that are becoming more acidic, and local threats such as improper land use resulting in increased nutrient loading, and over-fishing, which can trigger an ecological cascade resulting in blooms of seaweed that inhibit coral growth.

Trade can be a strong incentive for conservation, but this emerging local conservation tool may be at risk from well-intended restrictions to trade such as ESA listing, and similar prohibitions, intended to protect corals and coral reefs. Restrictions such as these may eliminate the benefits of the trade revealed by the study. These benefits include putting a value on intact coral reefs, and providing a greatly needed income for many in the island nations where hundreds of millions of people rely on the reef for subsistence. A more selective regulatory approach that allows local efforts to sensibly manage reef resources may be preferable.

Editorial comment

It is refreshing to see a study that emphasises the value of the reef aquarium hobby to those living in supply countries who rely on the reefs for their meagre livelihood. Putting greater value on the reefs locally would, hopefully, bring about a reduction in destructive fishing methods such as dynamite fishing and the use of cyanide

In recognising the value of the trade in corals as a positive tool for reef conservation it would seem appropriate if some way could be found for these mostly poor, subsistence fisherman to gain greater benefits from the aquarium trade, acknowledging their role in managing the reef environment.

As an aside, it’s interesting to see that the decline in trade varies species to species and the comments regarding new species, suggesting that species popularity may be subject to fashion and whim rather than an desire to recreate a realistic portrayal of the wild reef in the home aquarium.

Tim Hayes

Reef Ramblings

©2012

The Florida Fish and Wildlife Commission (FWC) made several changes and clarifications to marine life management, defined as tropical ornamental species, at its September Commission meeting in Tampa on Wednesday, including a three-year ban on the collection of the giant Caribbean Sea anemone, Condylactis gigantea.

Photo Robin Hayes ©2012

The prohibition of the collection the giant Caribbean Sea anemone was at the request of the Florida Marine Life Association (FMLA), the organisation of collectors that supply fish and invertebrates to the aquarium industry, and has the aim of letting their dwindling population recover and rebuild. The FMLA said that the anemone has suffered a sharp decline in the past few years, possibly from excessive collecting and partly from the cold weather that blanketed southern Florida in 2010.

The ban takes effect on 1^st November. Up until now commercial divers have been able to take up to 200 anemones per trip, and recreational divers could take up to five per day but it has taken more effort for divers to reach these quotas over recent years. In the early 2000s Commercial divers noticed a decline in the number of anemones in the Middle and Upper Keys. Landings of the giant anemones dropped from 227,238 in 1994 to 28,656 in 2011.

The FWC will return to the issue within three years with a proposal for future management of this species.

Management is important given the central role of Condylactis gigantea in the local ecosystem, where it provides shelter to a variety of commensal species including fishes and Periclemenes species cleaner shrimp, and serves as fish cleaning stations. The decline in numbers of this anemone might have a knock-on affect adversely influencing many other species.

The ban will prohibit collection in Florida waters, but Condylactis anemones should still be available from other locations, as it has a wide distribution in the Caribbean Sea and the Western Atlantic Sea, ranging from southern Florida through the Florida Keys to as far south as Brazil and east as Bermuda.

Other changes and clarifications by the FWC include:

• Removal of unicorn filefish, sand perch and dwarf sand perch from what is considered marine life, which will allow these species to be harvested with traditional fishing gear, such as hook and line and cast net, and without the requirement that they be kept in an aerated live well. The recreational bag limit of five of each species per day will no longer apply.
• Clarifying that size limits for angelfish extend to any hybrid forms of the species.
• Clarifying that commercial size limits for angelfish and butterfly fish apply to all harvesters, including recreational.
• Clarifying that the reefs built by Sabellarid tubeworms are live rock and, therefore, cannot be harvested.
• Prohibiting the harvest of black corals, which are already prohibited from harvest in federal waters.
• Expanding the definition of snapping shrimp to include all marine life snapping shrimp species.

Further information:

Concern has been raised as early as 2001 about the status of Condylactis gigantea and its collection for the aquarium trade. see:

Chiappone M, Miller SL, Swanson DW (2001) Condylactis gigantea – A giant comes under pressure from the aquarium trade in Florida. Reef Encounters 30: 29–31.

More recent information on collection for the aquarium trade can be found here:

Crawling to Collapse: Ecologically Unsound Ornamental Invertebrate Fisheries

Tim Hayes

Midland Reefs

©2012

”

3rd September 2012

Over the last few days, starting Thursday 30^th August, we’ve been experiencing what appears to be a run of daily ostracod spawning events. I say ‘appears to be’, as I’ve been unable to find much in the way of details about marine Ostracod reproduction but have found reference to eggs hatching into nauplius larvae which already have a hard shell (Barnes). Otherwise descriptions of ostracod reproduction seems to be vague, describing eggs as being laid in the water as plankton or being attached to vegetation or to the substrate, with some species brooding the eggs inside the parent’s shell. With thousands of species of ostracod it makes identification difficult for anyone other than an ostracod specialist.

Each morning we’ve encountered large numbers of ostracods floating on the surface of a single tank, part of a 1000+ litre, 12-tank critter system. Roughly one millimetre in length and half a millimetre in depth they are forming what I’d describe as an egg raft, with up to a couple of hundred individuals clumping together.

Ostracod ‘Egg Raft’
Midland Reefs ©2012

To be more precise, I should say that they are floating on the surface of the water. This is odd as most small organisms in this size range often have difficulty at the water surface owing to surface tension, a boundary that they are unable to cross, either water to air or air to water. Without intervention small organisms remained trapped by surface tension; localised stirring can breakdown this boundary enabling small organisms to penetrate it and enter the water column.

What is difficult to understand is why these ostracods are on the airside of the water surface as the feed to the tank is below the surface and I can see nothing about the layout of the system that would allow them to be just ‘poured’ onto the surface.

In the reef aquarium ostracods are most commonly seen close to the viewing pane moving around on (and in) the top layer of the substrate. Once harvested from the surface of the water of this single productive tank on the critter system, and mixed into the water column, they quickly settle to the substrate exhibiting the commonly observed behaviour as above.

If we can find out how to intentionally harness this form of reproduction it may prove to be useful in mariculture as another natural food for larval fishes or early juveniles.

I’ve been feeding a proportion of each day’s harvest to our resident population of young clownfishes who are eagerly consuming them.

If anyone out there has an explanation for what is occurring or has had any experience of this phenomenon, please get in touch.

To learn more about ostracods, see Reef Ramblings ‘Zooplankton in the Reef Aquarium – Ostracods’

Tim Hayes

Midland Reefs

©2012

27th July 2012

At the time of writing the UK is going through a period of very warm weather so it’s a good time to remind you about the danger that overheating can present to your reef tank. At this time of year reef aquaria can often reach potentially dangerous temperatures, bringing with it two distinct problems: heat induced coral bleaching and depleted oxygen levels.

Saltwater has a lower capacity for carrying dissolved oxygen than freshwater, as temperatures increase this carrying capacity reduces, in a reef with poor gas exchange the level of oxygen in the water can easily drop low enough for animals such as fishes and mobile invertebrates to asphyxiate.

I’d suggest checking that all pumps are working properly and efficiently and making provision for increasing your water movement in case of a prolonged period of hot weather. Making sure that the surface of the water is sufficiently agitated will both enhance gas exchange and aid temperature control via evaporative cooling. I’m currently recommending around a centimetre of “wave height” on the surface of the water, you’ll find that this will also enhance the effect of glitter lines, especially in an aquarium lit with fluorescent lamps.

Although you can mitigate the effects of high temperature induced oxygen depletion by increasing gas exchange, this will only go part way to helping corals to survive. This additional water movement can greatly enhance your corals chances of survival at higher temperatures and may be all that’s needed in some reefs, but ultimately you need to control the upper temperature reached in your aquarium.
It’s unfortunate that the cost of cooling a reef can often be as great, if not greater, than the cost of lighting it. Some reefs may need some form of cooling for the best part of the year owing to the way they’re lit. Your choice of methods of temperature control includes: refrigerant based chillers, evaporative cooling chillers, fans, air conditioners, and extractor fans.

Refrigerant based chillers and evaporative cooling chillers are the most expensive options.

Air conditioners are also expensive but they do have the bonus of controlling room temperature, which you and your family may well appreciate (it may also be a selling point to ”the significant other”, who may well have objected to the purchase of that expensive aquarium chiller!).

Extractor fans are useful to a degree but may make little difference once the room temperature is the same as outside.

Fans can be usefully employed to blow along the surface of the water to promote evaporative cooling, they’re cheap but do remember to take care in their placement as the last thing you want is a mains fan ending up in the aquarium! If possible choose a low voltage fan for safety.

Fans can also be extremely useful with enclosed aquariums and may improve how the tank runs on a daily basis, rather than just at times of high temperature, by improving gas exchange at the surface.

Don’t be tempted to turn aquarium heaters down or off as this will have no influence on water temperature during a warm period, indeed it can be detrimental to your reef when normal temperatures resume if you forget to turn them back on; if you see that a heater is turning on when your tank is running at an elevated temperature it is faulty and needs to be replaced.

Tim Hayes

Midland Reefs

©2012

Today while I was doing some house keeping on the Reef Ramblings website I was surprised to discover that it has now been going for five years.

The first Reef Ramblings online was published on the 10^th February 2007 at 17.05 and entitled, ‘Reef Ramblings Revived!’ and featured the following subtitle…

Reef Ramblings.

or …

A philosophy of sorts, on all things reef …

Reef Ramblings was originally a print column in Practical Fishkeeping magazine at a time when I provided the bulk of its reef content, offhand I can’t recall the date of the first column, probably sometime during 2004 or 2005, and ran until late 2006.  I then had numerous queries about what had happened to the column so, as a result of the interest shown, decided to resurrect the column online.

Over the last five years more than 220 articles of one sort or another have been published here, that’s around 44 per year, considerably more than the 60 columns that would have appeared in print over that time.

It remains a fairly eclectic mix of content with news about the natural environment, issues concerning reef keeping, talking about new equipment, commenting on different ways of running a reef, and now features a lot more coverage of the ethics and responsibilities of the hobby.

I don’t know how many of you out there actually read these articles but I hope you have enjoyed them to date and found some value in them, I also hope that you’ll agree that I’ve stayed true to my introduction in the first ever column where I promised an occasional series of incoherent ramblings on all things reef! I just hope its not been too incoherent…

Tim Hayes

Midland Reefs

©2012-02-12

Since its launch in 2005 the magazine Amazonas, edited by Hans-Georg Evers, has been widely considered to be one of the finest aquarium hobby publications in the world.  Up until now it has only been published in German. This year, 2012, sees the launch of the long-awaited English version with Volume 1, Issue 1, dated January/February 2012.

Amazonas issue 1, January/February 2012.

It’s fair to say that no better publication currently exists for dedicated freshwater hobbyists. Each issue featuring cutting-edge articles on fishes, invertebrates, aquatic plants, field trips to tropical destinations plus the latest in husbandry and breeding breakthroughs by expert aquarists, all accompanied by excellent photography throughout.

From the publishers of Coral magazine, this is a freshwater-only magazine with the same excitement and cover-to-cover excellence as Coral. Richly illustrated with high quality colour images and packed with in-depth articles by renowned authors, Amazonas appears every two months.

Coverage includes: new species, new ideas, new expert accounts on keeping and breeding freshwater fishes and invertebrates, planted tank aquascaping, travel to tropical source countries, visits to the fish rooms of legendary home aquarists and breeders, aquarium practice, biological background reports, aquarium technology and chemistry, interviews and much more. All printed on high-quality, sustainably harvested papers and non-toxic, soy-based inks.

The name ‘Amazonas’ is derived from the native Portuguese and Spanish name for the Rio Amazonas, the river that the Western world calls the Amazon.

I have a pre-publication sample issue and have to say that it lives up to the reputation of Coral magazine with amazing photography and in depth articles of a quality not seen elsewhere. If you are a serious fish keeper and value information, rather than the same old aquarium magazine content, you will not be disappointed.

Following the lead of Coral, the cover subject is dealt with in detail through extensive photo-reportage, accompanied by several in-depth accompanying articles.

As with the early issues of Coral, this first issue of Amazonas is sure to become a collector’s item.

See Midland Reefs: Amazonas

Retailers, if you are interested in stocking Amazonas, please contact us at Midland Reefs.

Tim Hayes, Midland Reefs, January 2012.

A recent piece of research delivered as a poster presentation at the annual American Geophysical Union meeting during December 2011 brings into question the formulation of the aquarium foods with which we feed our fish. See LiveScience for the original story that prompted me to write this article.

The poster by Greg Michalski, an assistant professor at Purdue University, highlights a quirk of science that although amusing, may be of concern to aquarists wanting to ensure their fish are fed an appropriate diet.

The poster presentation was a report on research based on chemical analysis of nitrogen isotopes in the food chain. The heavier isotope nitrogen-15 accumulates with each level on the food chain whilst the lighter form, nitrogen-14, tends to be excreted. An animal retains the heavy nitrogen from the animals it eats, while losing some of the lighter nitrogen. With each step up the food chain, the ratio of heavy to light shifts in favour of nitrogen-15. So, a plant would have the lowest levels of heavy nitrogen, and a top predator, say a shark or a tiger, would have the highest. This is a similar mechanism to the accumulation of the toxic element mercury in animals higher up the food chain

Michalski, who uses isotopes to study pollution and nitrogen cycling, had his students test seafood as a training exercise. Not surprisingly, they found that filter-feeding animals, like clams, came up with relatively low nitrogen-15 levels. Fish at the top of the food chain, like tuna and swordfish, had the most. However, as they studied a wider range of subjects they discovered an anomaly when they found some of the highest levels of heavy nitrogen ever recorded in …

 … the common guppy!

Tim Hayes Midland Reefs ©2007-11

The nitrogen enrichment being studied is expressed as the ratio of heavy to light nitrogen in the air. In the guppy, however, they found an increase in heavy nitrogen of 0.149 percent relative to that ratio. By comparison, they analyzed a sample from a thresher shark, a predatory shark, and found it had a 0.143-percent enrichment. Comically this turns the humble guppy into a predator at the very top of the food chain.

The reason for the anomaly turns out to be the aquarium fish food fed to the guppies. Their analyses revealed that fish food is positioned in the middle of the food chain, in the vicinity of salmon, mahi mahi, octopus or cod. Generally fish food comprises the leftovers from commercial fisheries: fish heads, guts and fins, the heavy nitrogen contained in it becomes further concentrated when eaten by the top predator, aquarium fishes, in this case, specifically the common guppy.

Although we don’t know what make of aquarium food was being fed to the guppies in the study it does open up questions about the formulation of fish foods and how appropriate they are for the species that they are being fed to.

In nature guppies are fairly low in the food chain, digestive tracts of wild guppies, Poecilia reticulata contain mainly benthic algae and aquatic insect larvae, a diet far different to the one rich in fish represented by the aquarium food in the above study.

For some time now I’ve been pointing out that the majority of fishes kept by reefkeepers are not fish eaters, rather they have a diet comprised of small zooplankton. Similarly the majority of the popular small fishes in the freshwater hobby are not fish eaters.

When you choose a food for your fishes do some research, examine the manufacturers literature and the content on food labels to ensure that you are feeding your fish an appropriate diet. You may find that you need a variety of foods to accommodate the diets of the different species that you keep.

Tim Hayes

Midland Reefs

©2011

Marine aquarium fish collector Steve Robinson was sentenced to 45 days in prison on Thursday15th December for smuggling dozens of exotic fish from a small island near Mexico. He is facing prison after pleading guilty to smuggling a rare species of fish that can worth up to $10,000 per animal by claiming they were a more common species.

© D Ross Robertson, Smithsonian Tropical Research Institute

Federal prosecutors accused Robinson of collecting 52 Clipperton angelfish in April 2009 off Clipperton Island. The Clipperton angelfish Holacanthus limbaughi is endemic to the area, growing to 25 cms total length, and is listed by the IUCN as Near Threatened (NT). Clipperton Island is an uninhabited atoll southwest of Mexico under French authority where fishing requires permission from the French government.

Federal fish and wildlife investigators found that Robinson then imported the fish into the United States while falsely claiming to authorities that they were a different, more common species.

Robinson pleaded guilty in August and is scheduled to begin serving the sentence January 30. The presiding United States Magistrate also ordered Robinson to pay a $2,000 fine and a one-year period of supervised release.

Tim Hayes,

Midland Reefs

©2011