Category Archives: Featured


Fluorescent cichlids – Taiwan Researchers Unveil Glow In The Dark Cichlids?

The Council of Agriculture in Taiwan surprised the world last week by stating that they had successfully created fluorescent cichlids. These cichlids were created by breeding  trangenic Convict cichlids and Angelfish.

The creation of this fish was the brain child of the Academia Sinica, Taiwan’s national research academy, and took just shy of 7 years to accomplish.

Some other innovative fish that this group has cooked up are the GloFish Zebra danio (Danio rerio) and the fluorescent Medaka (Oryzias latipes). These fish have been authorized for sale, and quite popular, since 2003 when they first hit the market in Taiwan as an aquarium fish.

Dr. Chih-Yi Chen, the head of the investigative team which created this cichlid, has stated that creating this cichlid took a lot of effort because of the lack of control they had over the spawning process, as compared to the smaller fish they previously tinkered with.

The scientists had to literally sit by the aquarium and wait for the fish to spawn so that the gene fragments could be immediately inserted into the Convict cichlid eggs. If it is not injected immediately, the results don’t seem to take.. This made the whole process very fickle.

An even greater obstacle was overcome, when they were in the process of spawning the fluorescent angelfish, as the couldn’t use micro-injection techniques in the same manner as with the Convict cichlids. In this case, they needed to apply an electric field to the cell membrane, in order to inject the gene fragments.

Well, they pulled it off.. The only question now is… What the heck is it good for? A fish nightlight?

Fluorescent Convict cichlid (Amatitlania nigrofasciata)

Fluorescent Convict cichlid (Amatitlania nigrofasciata) - Pic by JY Lin Co Ltd

Fish Have Good Memories and Can be Quite Cunning


Apparently, and hardly supprising for any one who kept fish for some time, the old belief that a fish only has a three second memory is complete balderdash. In fact scientists have discovered that fish actually do have quite a good memory, and can actually be quite smart. They have also been noted to be capable of working in a team, and even acting quite deviously.

One scientists, Dr. Kevin Warburton, who has been engaged in research on the subject for many years, has discounted the whole three second fish memory idea, as “absolute rubbish”.

Fish have been discovered to be far more clever, than was previously thought.

Dr. Warburton expounded, “’Fish are quite sophisticated. Fish can remember prey types for months. They can learn to avoid predators after being attacked once and they retain this memory for several months. And carp that have been caught by fishers avoid hooks for at least a year. That fish have only a three second memory is just rubbish.”

Dr. Warburton’s research has been focused on the freshwater fish of Australia, and has been taking a look at how Silver Perch actually learn how to handle the varying kinds of prey they come into contact with.

He has also said that the fish seem to exhibit human behavior in some instances. “Some behavioral traits that we think are very human, such as deception, fish have as well,” Dr. Warburton explains,

“Fish can recognize other individuals and modify their own behavior after observing interactions between other individuals. For example Siamese fighting fish will attack other members of the same species more aggressively if they’ve seen them lose contests with other fighters.”

It has been noted that in reef environments that cleaner fish remove and eat parasitic organisms off of larger “client” fish. “But what’s fascinating is that they co-operate more with clients when they are being observed by other potential clients.” Dr. Warburton added. ‘This improves their ‘image’ and their chances of attracting clients. Some cleaners co-operate with small clients to raise their image so as to deceive larger clients, which they then cheat on by biting them rather than removing their parasites.”

The fish even take a second look at potential predators to see how much of a risk they pose. “For added safety, they often do this as co-operating pairs, with the two fish taking the lead alternately. They will approach predators most closely when they have co-operated in previous inspections.” he explained.

Some minnows will even recognize a dangerous environment by associating a certain smell in the water with “alarm” chemicals that are released by other minnows who were felled by a predator.

This just goes to show you, that fish not only are not as affable as we once thought them to be, but actually have an intricate social structure, advanced forms of communication, and can literally swim circles around their prey. This we need to re-evaluate our entire conception of these creatures.

BP Facing Lawsuit to Stop Burning Sea Turtles

Green sea turtle

Green sea turtle - Picture by: Mila Zinkova

– BP is in some very hot water over their practice of burning sea turtles, while trying to clean up their mess in the Gulf of Mexico. The initiative is being headed by the Center for Biological Diversity and the Turtle Island Restoration Network.

They officially notified the U.S. Coast Guard and BP of their intent to launch a lawsuit for them to stop burning endangered sea turtles alive, and have given an ultimatum of 60 days in order to do so. If the action is not stopped a lawsuit will be filed under the Endangered Species Act.

Todd Steiner, biologist and executive director of the Turtle Island Restoration Network has this to say on the subject “BP is burning turtles alive and it is cruel, heartless and a crime we can’t and won’t allow to continue, sea turtles were critically endangered before BP created America’s worst environmental catastrophe, and every effort possible must be taken to rescue endangered turtles from this oil spill. BP needs to reverse course and help double our efforts to rescue sea turtles, not prevent their recovery.”

The spill really did happen at an inopportune time, as the rare Kemp’s ridley sea turtles started to nest in the Gulf of Mexico.

BP wound up in this mess, as they started a burning process, as they didn’t allow enough time for rescue boats to make a search, and get the sea turtles out of harms way.

Is the Perfect Prawn here at Last?

Tiger prawn

Tiger Prawn

The boys in white lab coats over at CSIRO and in the prawn industry have managed to breed and improve upon Black Tiger Prawn, and they are producing bumper crops in aquaculture farms and have been winning awards.

These prawns are so good in fact, that they have even won FIVE gold medals at the Sydney Royal Easter Show for the past two years running, including “Champion of Show” which happens to be the most decorated award possible.

The boys in white over at CSIRO’s Food Futures Flagship have tweaked the Black Tiger Prawn DNA, to make sure that the breeding program they have running captures the elite of the group and boost performance of their stocks every breeding season.

For the past several years, about fifty percent of all the prawns sold in Australia were imported from other countries such as Vietnam and China, so developing a local prawn which breeds in captivity is an extraordinary gain for both the local prawn industry and hungry consumers wanting to buy local seafood.

Dr. Nigel Preston, leader of the CSIRO Food Futures Flagship, had this to say about this exquisite prawn. “The new prawn’s yield has exceeded all our expectations. The average industry productivity for farmed prawns is only five tones per hectare, so this year’s average yield of 17.5 tones per hectare is a major leap forward, these huge yields can be replicated year after year which means consistent supply of a reliable and high quality product – all vital factors for the long-term growth and prosperity of the Australian prawn farming industry.”

Aquaculture has yielded approximately 17.5 tones per hectare, more than double the average production in the industry, all thanks to Dr. Preston’s super prawn. Several of the ponds produced 20 tones per hectare, and one even produced a record breaking yield of 24.2 tones per hectare.

Theorists say that if the rest of the Australian Black Tiger Prawn industry followed suit, and adopted this new DNA tweaking technology, Australia’s production could more than double, adding a $120 million boost to the annual value of the industry by the year 2020.

Mr. Nick Moore, general manager of Gold Coast Marine Aquaculture, had this to say about this revolutionary new prawn, and about Dr. Preston’s work.. “Thanks to outstanding work by the staff here, aided by close collaboration with our partners at CSIRO, we have just finished a prawn breeding season that can only be described as staggering, not only have we achieved national and international yield records with no reduction in quality or taste, these prawns are grown in a specially designed, environmentally sustainable production system. This production system and the new breeds have produced a perfect prawn with beautifully textured meat, rich color, robust size and a great taste. The awards (Sydney Royal Easter Show) are professionally judged on many criteria including size, color, taste and texture, so the results speak for themselves.”

With predictable output, and supped up prawn.. Australia is set to make its mark on the prawn industry.

Grown tired of you fish? Drop in the mail box!

fishmailbox

Sounds weird? If so you haven´t heard about the ”fish mail box” in Inada Park, Kawasaki, Tama River in Japan near Tokyo. The ”fish mail box” is a 7 meter by 4 meter large concrete water tank that have been placed along the river to give people a place to drop unwanted fish. The goal of the fish box is to prevent people from releasing fish into the river, since foreign species can wreck havoc with local ecosystems.

People are encourage to call before they drop off their pets as fish can die from the shock if not acclimatized correctly, but it is is permitted to just drop off fish as well. People are also encouraged to drop off tropical invasive species they catch in the river in the fish box.

The fish left in these fish boxes are cared for by Mitsuaki Yamasaki, 51, the head of a local river fish association, before they are placed in new homes. The box is receiving about 10,000 fish a year ranging from small fish to large gars.

The Tama River has seen a lot of new species released in it in recent years during which the aquarium hobby has become even more popular in Japan than before. This has in no small part to do with the movie “Finding Nemo”, even if the increase in popularity started before the movie was released. More than 200 species of foreign tropical fish have been found in the Tama River ranging from typical aquarium fish such as guppies and angelfish to less frequently kept creatures like piranhas and arowanas, earning it the nick name the Tamazon River. Some of the tropical species have established breeding populations while others haven´t, but most species can survive the winters by staying near water treatment areas along the river.

Mitsuaki Yamasaki and other members of the local river fish association are afraid that breeding populations of gars will establish themselves in the river since more and more gars are sold and they have been found in the river. Gar species are predatory fish that could have a severe negative impact on native fish such as sweetfish . Gars are likely able to establish breeding populations in a river with the conditions of the Tama River.

It can not be denied that with over 10,000 fish received by one of these fish boxes since it opened the initiative could aid the struggle to prevent invasive species from getting a foothold in local waters, and it might be an idea that deserves being tried in other problems areas around the world, such as Florida. The only question is if projects like this could work with out the devotion and support from people like Mitsuaki Yamasaki, people who are really passionate about what they do.

Any one interested in or planning to start a similar project somewhere else is very welcome to contact us here at AquaticCommunity as we would love to document your work getting the project of the ground and running it. Leave a comment in the commentary field or send an e-mail to admin@aquaticcommunity.com.

BP-oil threatens cold-water corals

Oil spill

Photo by: Igor GOLUBENKOV

Thousands of barrels of oil continue to leak into the ocean from British Petroleum’s Deepwater Horizon each day, and as we have been able to see in countless news reports a lot of it reaches the surface.

Less well known is that a significant portion of the oil never make the full 1 502 meter (4928 feet) journey to the surface. Instead, the stratified waters of the Gulf of Mexico capture the oil or slow down its ascent, and this oil is now threatening numerous life forms far below the surface.

According to Dr Gregor Eberli, Dr Mark Grasmueck and Ph.D. candidate Thiago Correa – all three from the Marine Geology & Geophysics division of the University of Miami (UM), the oil that fails to reach the surface is a serious threat to planktonic and benthic life throughout the region, including many species of cold water coral. Planktonic life is all the tiny living creatures the drift around in the ocean, while benthic life is life confined to the sea floor.

The deep water communities within the Gulf of Mexico and in the Straits of Florida are well hidden from us, but they include many species of cold-water corals that live in water at depths of 600 — 1500 m. (1969 -4921 ft.) in waters as cold as 3° Celsius (37.4°F),” Eberli explained.  “Unlike their more familiar shallow-water counterparts, these corals do not live in symbiosis with unicellular algae called zooxanthellae, but are animals that feed on organic matter floating through the water column. We know that most of the food consumed by the cold-water corals is produced in the surface waters and eventually sinks down to the corals.”

To make the problem even worse, the large plumes formed as a result of the oil spill has placed themselves between the deep-water corals and their food source. Some of these plumes are several miles long, and organic material – i.e. animals and plants – that sink through the plumes will become contaminated by micron-sized oil droplets. These droplets might not look as dramatic as a sea surface filled with crude oil, but they are equally damaging.

It is most likely that the delicate cold-water corals are not able to digest these oil-laden food particles and will perish in large numbers,” said Eberli. “We are especially concerned because the migrating oil plumes have the potential to destroy or greatly diminish these deep-sea coral communities as they are carried by the currents. These corals are important because they are the foundation of a diverse ecosystem that at last count includes over 1,300 marine species, according to Dr. Thomas Hourigan at NOAA.”

Severe damages might not be limited to the Gulf of Mexico

The Loop Current transports water from the Gulf of Mexico to the Atlantic Ocean, passing through numerous significant coral sites on its way from the eastern Gulf of Mexico through the Straits of Florida and northward to the Blake Plateau off North Carolina. The water enters the Straits of Florida to form the Florida Current and further north the Gulf Stream. Tiny droplets of oil suspended in the water could therefore wreck havoc with ecosystems far away from British Petroleum’s Deepwater Horizon.

While several (albeit not perfect) methods do exist for cleaning crude oil from the surface of the ocean, we know hardly anything about how to rid the water column from oil plumes.

The sound of reefs essential for corals

Reefs

We tend to think about corals as stationary animals, almost plants, but they do have a free-swimming stage when they are very young. A team of scientist working in the Caribbean Sea has now found that during this stage, the tiny corals find their way to suitable homes by listening to the distinctive sounds produced by reef dwelling animals.

The big question is now if the increasing noise pollution of the ocean brought on by human activities will affect the corals’ ability to find suitable spots for colonization. If free-swimming corals do not find a spot soon enough they die, and promptly being able to locate a fitting surface is therefore of outmost importance for them. Numerous human endeavours pollute the sea with various sounds, from boating and shipping to drilling, pile driving and seismic testing.

A few years back, Dr Steve Simpson, Senior Researcher in the University of Bristol’s School of Biological Sciences, was able to show that reef fish utilize sound to locate coral reefs in the ocean. The Carmabi Foundation Team working in Curaçao in the Dutch Antilles wanted to see if this was true for corals as well, and therefore set up a ‘choice chamber’.

A choice chamber is a device where small invertebrates, such as corals, are given the option to choose between two or more different conditions. The Carmabi choice chamber was filled with coral larvae belonging to the species Montastraea faveolata, the main reef building coral in the Caribbean Sea. The scientist then played recordings of a coral reef, and the corals turned out to very much favour moving in the direction of the sound.

Free-swimming corals are tiny and look a bit like miniscule hairy eggs. How they manage to detect sounds remains unknown.

At close range sound stirs up water molecules, and this could waggle tiny hair cells on the surface of the larvae, providing vital directional information for baby corals,” said Dr Simpson.

The results of the study, which was headed by Dr Mark Vermeij, has been published in PLoS ONE.

http://www.plosone.org/home.action

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0010660

The research was funded through a fellowship to Dr Simpson by the Natural Environment Research Council (NERC, UK) and by the National Science Foundation and Scripps Institution of Oceanography (USA).

More information can be found at

Why does the thresher shark have such a large tail?

Tresher shark

The long caudal fin has puzzled marine biologists, since it has been difficult to see any use for this enlarged fin. Recent research has however unveiled that the sharks’ tail seems to play a vital role when the thresher shark hunt small prey fish. Thanks to its large tail, the thresher shark can easily swat and stun small fish in the water. This is probably also why thresher sharks often get their tails caught in long-line fishing equipment baited with small fish – the sharks are trying to stun the bait but end up captured instead.

The new findings doesn’t come as a surprise; there is for instance a report dating back to 1923 in which a thresher shark is described using its tail to catch food. The new study is however the first one to show exactly how it works.

The research, headed by Dr Chugey Sepulveda, has been carried out by biologist from The Pfleger Institute of Environmental Research in Oceanside, California, USA and the University of Massachusetts in Dartmouth.

While filming hunting sharks in the ocean, the research team was able to identify two distinct techniques for stunning prey. The thresher shark could waggle its body and surge forward, effectively forming a wave down its body ending in a tail flick, or the shark could simply position itself alongside the prey and make a sideways strike.

The common thresher is for now, the only species that this feeding behaviour has been documented for. But we hypothesise that all three actively pursue prey with their elongate caudal fins,” said Dr Sepulveda.

There are three species of thresher shark:

  • Common thresher (Alopias vulpinus)
  • Pelagic thresher (Alopias pelagicus)
  • Bigeye thresher (Alopias superciliosus)

The thresher shark study has been published in Journal of Fish Biology.

http://www3.interscience.wiley.com/journal/118483233/home?CRETRY=1&SRETRY=0

The research was supported by the National Science Foundation, the George T. Pfleger Foundation, the William H. and Mattie Wattis Harris Foundation, and the National Oceanic and Atmospheric Administration Bycatch Reduction and Engineering Program.