Penaeus monodon Sightings in the Western Hemisphere

A Discussion from the Shrimp List

Craig Browdy (browdyc@dnr.sc.gov): We had an interesting visitor to South Carolina a couple of weeks ago.  A very large and healthy Penaeus monodon was caught by one of our shrimp trawlers.  A few more turned up in North Carolina a while later.  Does anyone know where these shrimp came from?

Osires de Melo (odmelo@uol.com.br): A couple of years ago, some P. monodon were caught in northeast Brazil, a region where no one farms them.  A plausible guess was that the monodon were released with ballast water from vessels that had been in Asia.

Leland Lai (lelandlai@aquafauna.com): So much for biosecurity and quarantine.  It’s bound to happen and I wouldn’t be surprised if monodon is eventually found off Hawaii and stylies [P. stylirostris] off New Caledonia and/or Tahiti.  And P. vannamei is in ponds all over the world, silently plotting escape plans!  It’s called the globalization of shrimp.  Sounds kind of like Atlantic salmon and Cobia doesn’t it!  Ok, Ok, I’m just having fun during my lunch break.

Josh Wilkenfeld (josh.wilkenfeld@gmail.com): I remember hearing or reading the stories of the mysterious appearance of monodon off the coast of Brazil, and the theory that they might have come in with the ballast water of large ships.  I don’t really know about the mechanics of ocean going vessels, but I wonder how these ballast tanks are filled and emptied, how clean they are kept (free of toxic substances) and how good of an environment this might be for shrimp to survive in for any length of time.  If the ballasts are filled and emptied by pump, it would surprise me if mature shrimp could survive the trip through a pump and impellor.  PLs might be able to make it through the pumps, but might still have a difficult time finding enough to feed on over a period of days or weeks in this environment, unless, of course, they were feeding on other dying organisms, which is possible.

Again, I know nothing about how these large ships work, but just thinking logically, I’m guessing that they draw water into the ballast tanks when they are moving away from harbor, and though their draft can be quite deep, they are probably not drawing water from areas where they are likely to suck up large shrimp that are bottom dwellers.  So I suppose the most likely case that can be made for transoceanic ballast transport of shrimp is by pulling in near-coast PLs that may be on their way into nursery grounds.  Interesting idea, but I still wonder about how well they would do in a ballast tank environment.

I assume that ballast tanks are very well painted with the same types of materials that are used to protect the outer hull from corrosion and fouling, and tanks may also include, in one form or another, substances meant to discourage the settling of barnacles on the inner surfaces of the tanks.  I wonder if, in order to reduce maintenance, there are other procedures or substances used by marine engineers to keep the ballasts clean and discourage survival of hitchhikers, and if such antifouling measures might also be toxic to shrimp.

Contrary to the above considerations, it does not seem to me at all far-fetched to think that monodon have made their way into culture systems in South America, both in the early days, when not much thought was given to regulating the introduction of nonindigenous species, or even today, when some aquaculturists are willing to move animals illegally, thinking this will somehow give them a business advantage.  I think it’s been correctly assumed (if not scientifically proven) that the origin of IHHN virus in the Western Hemisphere was from early importation of monodon, and more recently, it’s probable that the Taura virus made its way into Asia by the extralegal importation of non-SPF (specific pathogen free) vannamei, most likely from somewhere in Central or South America.  The point is that it never surprises me to hear that people are willing to ignore the risks to the environment and potential negative impact to their own livelihood to bring in animals illegally, using whatever form of rationalization is convenient for them at the moment.

Illegal importation of exotic species is much more difficult to do in the USA, though perhaps still not impossible.  And there certainly have been monodon in various places in mainland USA in the past.  There were monodon and stylirostris at the National Marine Fisheries Service facility in Galveston, Texas, when I first went to work there in 1980, and I would guess that there were monodon (and other species) at other research facilities at various times as well.  Certainly, less attention was paid in those days to accidental escapes, although I do recall that we eventually installed a rather primitive chlorinator for treatment of water discharged from the hatchery at the Galveston facility.

If monodon were inadvertently transported by ship, or accidentally released from research facilities or early commercial trials at one time or another, it would be interesting to know if they have been able to survive and reproduce in their “new” environment.  I have a few follow-up questions for Craig Browdy (above):

1. Were the specimens captured in North and South Carolina sexually mature, and if so, was there any sign of ovarian development and presence of spermatophores?

2. Were the specimens in good enough condition so that tissue could be used for testing by PCR to see if they were carrying any known pathogens?

3. This is probably expensive, but I wonder if it might be possible to determine the origins of these mystery animals by communicating with someone from Moana Technologies, High Health Shrimp, or other groups that have done significant genetics work with monodon, to see if certain loci or markers could be used to characterize specific populations from different regions?

I started this reply much earlier in the morning, but had to drop it for a while, so just now saw Leland’s comments (above), which I agree with completely.

Patrick Wood (patrickjwood@yahoo.com): At the end of the day, does it make any difference?  The world is too complex to regulate everything.  The rules are bound to be broken, naturally or unnaturally, voluntarily or involuntarily.  The sum total of the earth is what one should look at—not man-made boundaries.

Josh Wilkenfeld (josh.wilkenfeld@gmail.com): I don’t know, Patrick.  I can agree that the planet and evolution set up their own set of rules, which if left untouched by humans, would have kept things running just fine.  As you pointed out, it’s probably impossible to reverse damage already done by thoughtless and sometimes inadvertent movement of exotic species from place to place, but that doesn’t mean that we should give up completely on attempting to do a better job of minimizing the environmental impact of our activities.

You are correct in pointing out that even the movement of SPF (specific pathogen free) animals poses risks, since accidental and/or intentional release of animals is almost impossible to prevent.  We would be tilting at windmills, however, if we attempted to completely eliminate the movement of exotic species throughout the world.  I think that some progress has been made in terms of educating people about the need to move animals in a responsible and safe manner (SPF and strict quarantine rules for non-SPF seems to be the only logical way).  We should continue to emphasize the importance of using SPF animals when working with exotic species, as well as working to improve performance of endemic species, so that they will be as commercially and economically attractive to use as foreign species may be, in this case, vannamei.

Regulations and laws are often ineffective because they are too difficult to enforce, and getting people to cooperate for the good of their environment or the planet as a whole, just doesn’t seem to fly.  The only thing that seems likely to work is economic incentives (or penalties).  The goal should probably be to make it as easy and preferably even more profitable for hatchery and farm operators to work either with SPF animals when using exotic species, or with SPF and/or SPF/SPR (specific pathogen resistant) local species, as it is to work with “illegal” and potentially dangerous imports.

At this point, I’m not really concerned about who may be responsible for the appearance of monodon on the Atlantic Coast of the USA.  These animals may be illegal immigrants (if they were released from a USA-based installation), but there is no deporting them at this point.  Like Craig, however, I am very curious to know their geographical origin and, if possible, the approximate time and location of their release or escape, so that we can begin to learn about and keep track of their progress, both in terms of movement and assimilation and their health.  After all, not all immigration is bad, and now that they are here, we should know as much about their past and future as possible.

Victor Suresh (avsuresh9@yahoo.com): Does anyone know of adult vannamei in fisheries off the coasts of Brazil or Venezuela?  Vannamei is an exotic species in these two countries, but I have not seen reports that it is established in the local fisheries there.

I was recently in Brazil and heard a comment similar to what Osires de Melo said (above) about the whitespot virus in southern Brazil being attributed to ballast water.  Hard to believe, but the Brazilians swear on it, saying that there has been no live shrimp importation into southern Brazil for a long time.

Stephen Newman (sgnewm@hotmail.com): It is my understanding that the animals off the coast of Brazil were there as a result of a failed shrimp farm several decades ago.  It is also my understanding that wild monodon are routinely caught off the northern coast of Brazil and have established themselves off the coast of Guyana (northeast coast of South America) as well.  There is no practical way to restrain the movement of animals as long as there is a value to someone for doing so.  There will be a strong trade in illegal animals and the movement of pathogens will continue to be an issue.  Tight regulation and extreme consequences for getting caught will deter some, but the existence of a thriving global black market ensures that these practices will continue to some degree.

David Griffith (dgriffith@caribbeanshrimp.com): I understand that monodon was imported into Venezuela and other parts of the Caribbean in the late 1970s and early 1980s.  About three years ago a couple of monodon were caught in Lake Maracaibo by artesanal fisherman (I saw one of these and have photos if interested), and I know of at least one monodon being caught off the Península de Paraguaná (Venezuela).  The issue was discussed on the Shrimp List (see Source below) a few years ago; the general consensus was that while monodon may be occasionally found, it hasn’t been caught in sufficient numbers to suggest established populations.

Alain Michel (alainhenri@aol.com): It is well known that monodon has extended its range to the west coast of Africa where it is frequently found in the trawler catches.  This new population is clearly a result of the escapement from shrimp farms in West Africa.  Maybe they got to the Americas by following logs across the Atlantic.  Concerning a potential settlement of all the exotic species that have been imported and reared as captive broodstock in Tahiti, it has never occurred just because there is no continental shelf.  The lagoon is very small and the slope out of the barrier reef goes straight down to a thousand meters.

In the South Pacific, monodon has just extended its range to Fiji, where there are enough mangrove areas suitable for them to make a living.

Mario Aguirre (mario.aguirre@spcorp.com): David Griffith’s comments are correct except that monodon was imported in the late 1980s by the Aquacam (now closed) shrimp farm in the Cariaco Gulf in Venezuela.  Also, three monodon have been caught on a shrimp farm in Venezuela.

Victor Suresh (avsuresh9@yahoo.com): Do you know of any vannamei caught from the ocean by fishermen in Venezuela or the Caribbean?  The reason I am asking this question is that one of the concerns expressed in using nonnative stocks is the possibility that the stocks will escape into the wild, become established and compete with local species.  Has the long presence of vannamei in countries like Venezuela and Brazil shown the potential of vannamei getting established in the wild?

Hervé Lucien-Brun (hlub@wanadoo.fr): Monodon is now relatively common on the west coast of Africa.  A monodon fishing industry has developed in West Africa, especially in Nigeria.  Several people think the origin of the West African monodon was a farming project in Gambia.  The farm failed and the technicians released the stock into the sea.  I don’t know if it’s true because several other monodon projects were initiated in the same area, the Ivory Coast, for example, without success.  After failing, the Gambian project was reborn, and it is now in operation again, this time with wild-captured monodon broodstock from Gambian estuaries.

Juan Aguirre (jxaguirre58@yahoo.com): In Ecuador, the Morrison group (Fincacua, Semacua) brought in monodon in the early 1980s and tried it in farms.  It wasn’t very successful and no sightings have been reported.  There are others (Phil Boeing, Bobby Padua) who should know the full story.

Camaxdron (camaxdron@yahoo.com): Monodon are in Guyana, Trinidad, Venezuela and Colombia (Caribbean side).  They are breeding and surviving with no apparent harm to wild shrimp.  They are entering and growing in vannamei ponds, being caught by trawler fleets, and increasingly, appearing at shrimp processing plants.  They’ve been here a long time.  They command better prices and grow faster than vannamei, and they may have acquired some resistance to our Vibrios and viruses.  How did they get here?  It doesn’t matter.  They may help us escape the current plague of low prices—and help us compete with the millions of tons of vannamei that are coming in from Asia.  Let's turn the “tortilla” on them.

See: Who's Got the Biggest Monodon?

Source: The Shrimp List (a mailing list for shrimp farmers, “shrimp-subscribe@yahoogroups.com”).  Subject: [shrimp] Monodon culture in the Americas.  October 16-25, 2007.

Country Reports

Australia

Gold Coast Marine Aquaculture

Nick Moore, general Manager of Gold Coast Marine Aquaculture, a shrimp farm in southeast Queensland that has its own PCR machine (polymerase chain reaction) to check for shrimp viruses in wild broodstock, says the recent ban on raw shrimp imports is great news for shrimp farmers.

Source: FisheNews (an email supplement to Austasia Aquaculture magazine, www.austasiaaquaculture.com.au).  Editor, Tim Walker (austasiaaquaculture@netspace.net.au).  Prawn/Gold Coast Marine Aquaculture to Expand.  October 12, 2007.

Bangladesh

Floods

In September and October 2007, heavy rains caused floods that breached levees and flooded much of southwest Bangladesh, the country’s primary shrimp farming area.  At least 256 shrimp ponds were washed away.

Source: The Daily Star.  Fresh flood in Satkhira (http://www.thedailystar.net/story.php?nid=7388).  October 10, 2007.

Canada

Advice Wanted on Drain Mesh Size

I need information on drain mesh size in postlarvae (PL-18 to PL-25) tanks with bottom drains—and don’t want to restrict water flow or suck shrimp into the filter system.

Information: John Tremblay (tremblar@telus.net), Alberta Shrimp Farms, Inc.

Source: The Shrimp List (a mailing list for shrimp farmers, “shrimp-subscribe@yahoogroups.com”).  Subject: [shrimp] PL drain mesh sizes.  From: Tremblay.  October 3, 2007.

China

Antibiotic Use Decreasing

Rohana Subasinghe, senior fishery resources officer for aquaculture at the United Nations’ Food and Agriculture Organization, says: “In my opinion and experience, the use of banned antibiotics and fungicides in Asia has decreased considerably....  I do not deny that farmers use banned antibiotics and fungicides.  But the usage has reduced significantly.”

Small farmers produce about 80 percent of the world’s farmed seafood, and most of those who use illegal veterinary drugs are unaware that they’re using them, notes Subasinghe.  “These people are not necessarily very well educated,” he says.  “So it is our responsibility to empower them to do a better job.  It’s extremely important to make them aware of global food safety requirements and international trading standards—what’s supposed to be used and what’s not supposed to be used.  Extension is a must.  However, many governments are becoming increasingly incapable of providing good extension.”

“In many countries, you can buy fish feed containing illegal veterinary drugs on the open market,” adds Subasinghe.  “When it’s freely available, you’re basically setting a precedence for increased usage.”

Bill More, director and VP of the Aquaculture Certification Council in Kirkland, Washington, USA, puts some of the responsibility on feed manufacturers because antibiotics are administered mostly through feed.  “Unscrupulous salesmen sell farmers feed containing illegal veterinary drugs and don’t tell them what it really is”, says More.  “You’ll see products like ‘Make Your Shrimp Grow Faster’ and ‘Happy Shrimp,’ but they don’t tell you what’s in the product; the government doesn’t always require it.  Small farmers, especially, have been taken advantage of.”

More also believes that the use of illegal veterinary drugs in Asia is falling.  “It’s very rare now that we find a product that tests positive,” says More.  “This year, we’ve taken over 1,000 tests from China alone from the two plants that we certified.  We’re making them submit tests through third-party labs every week.  These two facilities have been completely clean for almost two years now.  But these...plants...sell to companies like Darden and Wal-Mart,” he adds.  “So you really don’t expect to find tainted product in plants like that.  It’s the other plants you have to worry about.  Most conscientious farms, especially those integrated with processing plants, don’t use illegal antibiotics and fungicides anymore.”

George Chamberlain, president of the Global Aquaculture Alliance in St. Louis, Missouri, USA, says: “Fishmeal prices have been quite high.  So every feed manufacturer in the world is looking for ways to minimize the fishmeal inclusion level by utilizing alternate sources of proteins and fats.  In China, what would normally be typical alternatives, for example, rendered animal products, are huge red flags because they can’t be sure that they are absolutely free of all illegal antibiotics.”

“The whole point is to test upstream and reduce the need to test at the end of the pipeline,” explains Chamberlain.  “With end-of-the-pipeline testing, where millions of pounds of product are emptying into ports of entry, attempting to understand the history of a product with a few spot tests is futile.  It’s much more productive to test at the point of origin.”

The ACC recently added fluoroquinolones—including ciprofloxacin, enrofloxacin, sarafloxacin, flumequine and oxolinic acid—to the list of antibiotics that private labs are required to test for when it certifies shrimp farms.

Information: Bill More, Aquaculture Certification Council, Inc., 12815 72nd Avenue, Northeast, Kirkland, WA 98034 USA (phone 425-825-8634, fax 425-671-0146, email wrmore@comcast.net, webpage http://www.aquaculturecertification.org).

Information: George Chamberlain, Ph.D., President, Global Aquaculture Alliance, 5661 Telegraph Road, Suite 3A, St. Louis, MO 63129 USA (phone 314-293-5500, fax 314-293-5525, email georgec@gaalliance.org, webpage www.gaalliance.org).

Source: SeaFood Business (www.seafoodbusiness.com).  Editor, Fiona Robinson (frobinson@divcom.com).  Import Alert.  Steven Hedlund (shedlund@divcom.com).  V-26, N-10, P-24, October 2007.

India

New Tiger Prawn Research Center

India’s Agriculture and Fisheries departments are jointly setting up a tiger prawn (Penaeus monodon) research center on a 100-acre site in the state of Andhra Pradesh at a cost of about $13 million.  The agencies think the center will be operational by December 2008.

Source: Newindpress.com.  Southern News/Andhra Pradesh/Centre to help produce better quality tiger prawn (http://www.newindpress.com/NewsItems.asp?ID=IEA20071011013524&Page=A&Headline=Centre+to+help+produce+better+quality+tiger+prawn&Title=Southern+News+-+Andhra+Pradesh&Topic=0).  V. Kamalakara Rao.  October 11, 2007.

India

Surat

Shrimps farms in Surat (a port city in the state of Gujarat, northwest India) have been hit by whitespot.  Some 40% of the farms around Olpaad have been affected.  The loss has been estimated at $7.6 million.  The farms in the area export 2,000 tons of shrimp annually.  The outbreak may wipe out the entire crop, resulting in losses of $18 to $20 million.

This is the first time that farmers in Olpaad have faced whitespot.  In April 2007, however, 85 shrimp ponds in Samapur Village in the Navsari District were hit.

Low-quality, inexpensive seedstock from Mumbai may have caused the outbreak.

Source: The Economic Times.  Killer disease hits shrimp exports hard (http://economictimes.indiatimes.com/Markets/Commodities/Killer_disease_hits_shrimp_exports_hard/articleshow/2458380.cms).  Melvyn Thomas.  October 15, 2007.

India

Import Bonds and “Zeroing” Unfair

In a verdict that could prompt more Indian shrimp exporters to seek markets in the USA, the World Trade Organization’s (WTO) disputes panel ruled that the USA practice of collecting cash deposits in the form of bonds from Indian shrimp exporters was against international trade practices.

With the abolition of the bonds, Indian shrimp exporters to the USA will only have to pay the 7.22% dumping duty.  There are 75 Indian traders exporting shrimp to the USA.  In 2006-2007, their exports to the USA fell to $297.08 million from $372.62 million in 2005-2006.

Next India will take the USA practice of “zeroing” [a statistical procedure that leads to artificial and inflated dumping duties] to the WTO, an action that could reduce India’s duties dramatically.  Both Ecuador and Thailand have won cases against zeroing at the WTO.

Source: Livemint.com.  US shrimp import bonds unfair: WTO (http://www.livemint.com/2007/10/12014539/US-shrimp-import-bonds-unfair.html).  Ajayan.  October 12, 2007.  2. Bob Rosenberry, Shrimp News International, October 22, 2007.

Taiwan

Whitespot

 Lo Chu-fang, a researcher at National Taiwan University (NTU), says that genetic analysis is yielding new insights into the workings of the whitespot virus.  Her team is working on a way of inoculating shrimp against the dreaded virus, but added that there was much Taiwanese shrimp farmers could do to overcome the disease through better aquaculture practices.

“We found that during periods of stress, the level of WSSV increases in the shrimp’s body at an astonishing rate,” Lo said.  “For instance, we have observed virus levels increasing 100,000-fold during spawning, which is a stressful event.”

Local shrimp-rearing methods put a lot of stress on shrimp stocks because local shrimp farmers tend to adopt a very intensive approach, Lo said.  “We are talking about keeping up to a million shrimp per hectare whereas abroad 300,000 to 400,000 is the norm.”

“WSSV did not appear in Taiwan until 1992,” said Lo, who has been working on the virus for many years.  “Our research found that previously the virus was an obscure and largely harmless one affecting certain species of crab.”

Source: Taipei Times.  NTU researchers gain understanding of shrimp virus (http://www.taipeitimes.com/News/taiwan/archives/2007/10/12/2003382756).  Angelica Oung.  October 12, 2007.

United States

Mississippi—Freshwater Prawn Meat Yields

Most freshwater prawns produced in the USA are sold at the pond bank, or at farmers’ markets and other niche markets.  Generally, they are offered “whole, on ice” at the time of harvest, avoiding the costs of freezing and storage.  Customers frequently ask the following questions:

Question: If I buy whole prawns, what loss do I have to expect when they are deheaded?

Answer: In the table below, take a look at the “tail yield” column.  If you purchase 10 pounds of medium whole prawns, the tail yield will be 52.5%, or 5.25 pounds.

Question: What percent of this whole product is actually edible meat?

Answer: If you want to know how much meat you are purchasing when you buy medium whole prawns, take a look at “meat yield”.  The same 10 pounds of medium whole prawns provides 42.9% or 4.29 pounds tail meat.

Question: If I purchase shell-on tails, how much meat am I left with?

Answer: For a 10-pound purchase of medium, shell-on tails, you would get 81.6% meat or 8.16 pounds of meat.

The next table describes the time required to dehead prawns.  Calculations are based on average sizes.  This information is especially useful when calculating labor costs.

Source: Prawn Tales (the newsletter of the U.S. Freshwater Prawn and Shrimp Growers Association).  Editor, Mike Frinsko (Aquaculture Area Agent NC Cooperative Extension).  Freshwater Prawn: Tail Yield and Deheading.  Volume 6, Issue 1, Page 6, Late Summer 2007.

Vietnam

Grobest

In Asia, the Grobest Group is involved in a wide range of aquaculture operations, from hatcheries and farms to feed mills and processing plants.  In Vietnam, in partnership with I-Mei Industrial, it produces fish and shrimp feeds, operates a processing plant and runs a research hatchery/farm.

Shen Yen Ling, vice general manager, said Grobest feeds are traceable and its processing plants have received HACCP (Hazard Analysis and Critical Control Point, a USA/FDA program) and European Union accreditation.

Shen said: Culture of Penaeus vannamei is picking up in central Vietnam, around Da Nang, and in northern Vietnam, around Halong.  Selling prices have been attractive in comparison to the cost of production.  In June 2007, vannamei were at $3.15 for 100-count, whole animals per kilogram.  Recently that price declined to $2.50.  The food conversion ratio is low at 0.98.  At a stocking density of 200/m², the cost of production is $2.20 for 70 to 100-count, whole shrimp.

GroBest plans to set up a domestication center for P. monodon in An Giang Province (southern Vietnam, adjacent to Cambodia) that will become the center of its domestication program in Asia.

Grobest supplies SPF vannamei postlarvae and quality monodon postlarvae to shrimp farmers from its new hatchery in Nha Trang.

Grobest will also construct a new feed mill in southern Vietnam, near the Cambodian border, that will produce fish and shrimp feeds.  It will be in addition to the current feed mill in Dong Nai outside Ho Chi Minh City, which produces feeds for shrimp, grouper, catfish and tilapia.

Farmers culturing vannamei in the Nha Trang region use feed formulated for black tiger shrimp, but those in Da Nang use feeds specifically formulated for vannamei.  Shen said: “From our research, we know that when the feed is not cooked enough, feces are white.  This does not happen with our feed.  Feed formulation is also adjusted depending on salinity, seasonal changes (rainy versus dry season) and availability of raw materials.  No changes are made in the premix.  To maintain the quality of the shrimp feed, we raised prices twice in 2006 and once in 2007 because of large increases in raw material prices.  ...In Vietnam, our strong point is that we can assure feed quality quickly by using a NIR machine (near infrared analysis) to check feed composition, which is only possible if there is a large enough database on ingredients.  Each sample analysis takes three minutes.”

Grobest’s research and development on aqua feed production is carried out in Taiwan and transferred to the mill in Vietnam.  Consultants from the head office in Taiwan provide technical support to mills in China, Vietnam, India, Thailand and Indonesia.  Grobest has 120 salesmen and 8 technical staff for its shrimp and fish feeds.

Source: Aqua Culture AsiaPacific (Editor/Publisher, Zuridah Merican, email zuridah@aquaasiapac.com, webpage www.aquaasiapac.com).  Grobest I-Mei: Upstream Expansion.  Volume 3, Number 5, Page 39, September/October 2007.