Home | Aquariums and Fish in the News (page 3)

Category Archives: Aquariums and Fish in the News

Feed Subscription

Contains articles regarding fish and aquariums in the news.

New Fish Species in 2013 – Sharks, an Antarctic Monster, and More

Oarfish

Uploaded to Wikipedia Commons by LT DeeDee Van Wormer

Even considering that new fishes are discovered at the rate of nearly two per week, 2013 was a spectacular year for fish enthusiasts.  Included among the undescribed new fish species brought to light in 2013 were several relatives of common marine and freshwater aquarium fishes, numerous sharks (including a large hammerhead off South Carolina), a knife fish that utilizes a different type of electric current than all others, a bizarre beast from the depths of the Antarctic’s Ross Sea, one of the world’s smallest vertebrates, and one of the world’s largest freshwater fishes.  The diversity of these new species is staggering, and all seem to have amazing traits, so I was hard-put to select my favorites.  Please be sure to share information about those that caught your eye by posting below.

 

Giant Oarfish, Regalecus glasne

The Giant Oarfish is not a newly-discovered species…in fact, it has been inspiring tales of sea serpents for thousands of years.  But despite being the world’s longest boney fish, this 30+ foot-long behemoth is so rarely seen that I felt compelled to mention it here.  Fish-watchers were quite surprised when two individuals washed up off southern California in less than a week…and both were in great condition.  Measuring 14 and 18 feet long, one contained hundreds of thousands of eggs, while the other was infested with large tapeworm-like parasites.

 

Arapaima leptosoma

Uploaded to Wikipedia Commons by George Chernilevsky

Arapaima, Arapaima leptosome

At a weight of over 400 pounds, South America’s air-breathing, torpedo-shaped Arapaima is one of the world’s largest freshwater fishes.  It was not until 2013 that ichthyologists learned that a second species was “hiding in plain sight” (in commercial aquariums, even!).  Distinguishing the new species is important, as Arapaima have been hunted to near extinction across much of their range.  Slight differences in the natural histories of the two species may help us to understand how best to conserve them.

 

Blue-Bellied Night Wanderer, Cyanogaster noctivaga

The fish bearing this long name is, at 0.68 inches in length, one of the world’s smallest vertebrates; it misses being the world’s tiniest fish by a mere 7mm.  Size was not all that helped to keep this fish hidden for so long…it is also transparent and nocturnal, and “wanders” in the tea-colored waters of the Rio Negro.

 

Hopbeard Plunderfish, Pogonophryne neyelori

This fish’s appearance is stranger than its name.  Looking like a cross between an Oyster Toadfish and a tadpole, the Hopbeard Plunderfish was hauled up from 4,560 feet below the surface of the Antarctic’s Ross Sea by Ukrainian commercial fisherman.  As you can well imagine, we know nothing of its natural history (and, I’m guessing, may not for some time!).

 

Long tailed Carpet Shark

Uploaded to Wikipedia Commons by EurekAlert.org

Long-Tailed Carpet Shark, Hemiscyllia Halmahera

This 28-inch-long, attractively-marked shark is related to the Epaulette or “Walking” Sharks, several of which are popular in the aquarium trade.  A flexible body and leg-like pectoral and pelvic fins allow it to prowl about tide pools and submerged rocks in search of marine worms, crabs and shrimps.  Western Australian Museum ichthyologists discovered it off the East Indonesian island of Ternake, which is part of the Maluku Island chain.

 

Bluntnose Knifefish, Brachyhypopomus bennetti and walteri

Knifefishes, several of which are popular in the aquarium trade, are known to use electric currents to assist in navigation.  One species, the misnamed “Electric Eel”, also uses electricity to both hunt and defend itself.  The newly-described species emit electric currents from an organ in the tail.  Like all other electric-producing fish, B. walteri  releases alternating positive and negative pulses.  B. bennetti, however, is unique in that it produces only a direct, one phase current.  This fish lives below floating weed masses in Brazil, and seems especially prone to losing part of its tail to predators.  The navigational abilities of knifefishes that produce alternating currents are severely hampered if they lose a portion of the tail.  However, B. bennetti seems not to suffer when the tip of its tail is lost, as the direct current it produces functions just as well…an amazing adaptation if ever there was one!

 

More Sharks Discovered in 2013

The 8-12-foot long Carolina Hammerhead, Sphyrna gilbert resembles the better-known Scalloped Hammerhead, but is genetically and structurally distinct.  It is the largest fish to be found in such a developed area (inshore, off South Carolina) this year.

 

Sawsharks resemble sawfishes.  Their “saws”, which bear barbels at the half-way point, are used to disable the fishes upon which they feed.  The new species discovered in 2013, Pristiophorus lanae, hails from the Philippines.  Little is known of its natural history.

 

Further Reading

2012’s New Fish Species

2010’s Most Unique New Fishes

 

Actinic Light vs. Blacklight – Highlighting Fluorescent Livestock and Decor

Glo tetrasWith the growing popularity and availability of fish like GloFish and GloTetras and decorations like our own Pure Aquatic Glow Elements line, “glow-in-the-dark” and fluorescent aquariums are becoming more and more common. Most of these animals and decorations are brightly colored in any light but under special lighting, the colors will really glow. There are two main kinds of light that are used in these aquariums: “blacklights” and actinic lights. Knowing the difference between these two can play an important role in making your tank really stand out, as well as in keeping it healthy. For this blog, we will be focusing in general terms only for community aquariums. Aquarium with invertebrates and corals will have different needs since their light requirements are much more specific and extensive.

First, the science…

The colors we see around us come from the light’s wavelength, measured in Terahertz (THz) or nanometers (nm). Most people can see light ranging from about 700nm (reds) to about 400nm (purples). Blacklights and actinic lights both produce light from the bottom of the visible light spectrum (the BIV in ROY G BIV). Most actinic lighting for aquariums has a wavelength of about 420-460nm. The higher end of this range (460nm) produces a more blue color light, while the color shifts to purple approaching the lower end (420nm). This type of lighting is still well within what we are capable of seeing. “Blacklights” emit a light below what we as humans are able to see known as ultraviolet or UV light. Yes, this is the same UV light that we wear sunscreen to protect ourselves against! UV lighting is separated into three major ranges. Blacklight bulbs are UV-A bulbs (315-400nm), the spectrum which causes our skin to tan. For comparison, the UV Sterilizers popular in aquariums for eliminating algae, diseases and parasites are UV-C bulbs (200-280 nm), a destructive spectrum that is mostly filtered out by Earth’s atmosphere and the UV-B range in between is the more damaging rays from the sun that causes sunburn and other harmful conditions. Read More »

Reef Destruction – Molasses Spill Causes Near Total Destruction in Honolulu Harbor

September was a bad month for Honolulu Harbor and all of the fantastic fish, corals and wildlife that called it home. On September 09, 2013 over 233,000 gallons of molasses spilled into the harbor, sinking to the sea floor and suffocating everything in it’s wake. The cracked pipe that allowed the mess to flow into the harbor was repaired within days, but the damage caused by the viscous mess has been rapid and devastating.

You think of molasses and you don’t think of widespread death, but flood a pristine marine environment with sugary syrup and that’s the result. The heavy fluid ends up being lethal in several ways.  The goop clogs gills, suffocating fish quickly. It coats corals and inverts, robbing them of light, oxygen and water flow vital to their ability to thrive. The sugars are also a rich food source for marine bacteria which reproduce in massive numbers, depleting dissolved oxygen as their numbers grow.  The dissolved sugar alters the pH of the water and also creates what’s called an osmotic effect, basically dehydrating marine organisms whose living cells expel water in an attempt to equalize with their external environment. Within hours the death toll began to rise, and to date thousands upon thousands of fish, inverts, corals and even other animals like sea turtles have perished. 

Unlike oil spills that may be wicked off of the surface of the water, the nature of this spill means that cleanup of the molasses itself is not an option. The syrup will dissolve and nature will slowly eat it up and wash it out of the harbor and into the sea. Clean-up in this case means fix the leak, monitor the progress of the damage, and collect the carnage of dead sea creatures that wash up on shores and pile up in shallow areas so that predators like sharks and barracuda aren’t attracted to area. While some creatures may bounce back and return to the harbor pretty quickly, it may be years until the coral reefs, vital to the economy and ecology, in the harbor recover.

What a sad situation. Unfortunately, the only real course of action is to allow nature to clean up another man made mess. On the bright side, nature knows how to take care of herself, and despite the scope of the problem, this particular spill is in many ways still better than oil or some other chemical deluge. Now all anyone can really do is wait and see…

 

 

GloFish – It’s All in the Genes

Electric Green Tiger BarbsGloFish are some of the most popular, colorful and controversial fish to enter the aquarium trade in a long time. Their easy care, small size, peaceful nature and neon bright colors make them appealing to aquarists of all ages, but the modifications that cause these bright colors cause some debate among aquarists, scientists and environmentalists alike.

The original “GloFish” were not created for the aquarium trade. They came from a popular fish used in many different fields of research, the Zebra Danio (Danio rerio). Zebra Danios have been used in research for environmental studies, cancer research, genetics, reproductive biology, neuroscience and applications to other fields as well. They even made the trip to space in 1975 on the Russian “Salyut 5” space station. So what makes them such good research subject? Zebra Danios are easy to breed and it only takes hours for the internal organs to develop after the eggs have been fertilized (about 24-36 hours, depending on temperatures and conditions). During this time, it is easy for researchers to monitor the development of the embryo since the “shell” around the eggs is a clear membrane. The eggs can hatch about 12-36 hours after that (again, depending on the conditions). These variable time frames also mean that, while the development is being studied, conditions can be adjusted to slow down or speed up the development, depending on what exactly the researchers are trying to determine. The genetic sequence involving the structure of the Zebra Danio’s DNA and RNA is very well-known at this point and is comparable enough to our own that, by understanding how changes in this structure affect the fish, researchers are gaining more understanding into how changes in our genetic structure can affect our own health.

Originally, GloFish were being developed for two major fields: cancer research and pollution detection. In the late 1990’s/early 2000’s, researchers thought to develop a fish that would change colors when a certain pollutant was found in their water. The thought was to develop a fish that would appear normal in “ideal” conditions but when a specific chemical or type of chemical was present in the water, a “trigger” would be set off to cause the fish to “glow” with a fluorescent protein in their bodies. As a step in this direction, they began to develop a fish that would always have this flourescent “glow” in a reproducible and hereditary way that wouldn’t affect the ecosystem around them. To do this, scientists turned to a fluorescent protein naturally found in jellyfish, corals and anemones rather than potentially harmful chemical dyes. Around the same time, similar projects were using a fluorescent protein to “mark” specific genes that were thought to be a cause or sign of cancer. By pairing the fluorescent protein with the cancer-related gene, researchers could see the fluorescence increase or decrease along with the other gene and see if an increase or decrease in that gene was related to the cancer. Since the genes (and cancers) in these fish behave in much the same was as they do within ourselves, researchers are using this to develop a way to track, diagnose and treat cancer in people. Read More »

Dangerous Beauty – The Ongoing Threat of Invasive Lionfish Along the East Coast

Caught in the Virgin IslandsHow can something be so beautiful and yet so dangerous and destructive? Invasive lionfish are making headlines again, continuing their viral spread in the Atlantic and decimating native species as they explode in population. Lionfish are quickly becoming the poster species for the horrible things that can happen when a non-native species is introduced to a new region or habitat, left without predators to keep populations in check.

This isn’t a new story, just a continuing saga conveying the sad consequences of accidental or intentional introduction of non-native species. The story is believed to have begun sometime in the 80’s with lionfish being sighted between Florida and the Caribbean. Within 15-20 years the population exploded and at this point any hope of stopping the invasion has all but fizzled.  No one will ever know how they were introduced or where to place the blame. Some believe careless aquarists are at fault, releasing the fish into waterways if they became to large or otherwise unable to be kept. One popular theory is that the fish made their way into the Atlantic after a coastal hurricane destroyed a home or homes with aquariums that contained the Indo-Pacific natives, which miraculously found their way safely into east coast waters. Others believe it’s possible that juvenile or larval lions hitched a ride in ship ballast waters as other species have before, finding themselves in a new world when the waters were pumped out. Regardless, lions are here and here to stay, with only we humans as their predators. Read More »