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Dying Coral May Threaten Island Population

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The coral on the sea floor around the Pacific island of Kiritimati, sometimes called Christmas Island, looked like a boneyard in November stark, white and lifeless. But there was still some hope. Video provided by AP

Source: https://www.sciencedaily.com/videos/b130de92a531453c9d04038a20af8921.htm

Posted April 18th, 2016.

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WATCH: Ensnared Porcupinefish’s Pal ‘Keeps Vigil’ As Snorkeler Sets It Free

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Photo Courtesy: iStockphoto

A video of a porcupinefish trapped in a net in Chaloklum Bay, Thailand, being freed by snorkelers who happened upon it got lots of traction last week.

But it’s not just this act of kindness that’s driving the video to be viewed. There’s something special about the two-minute clip, even beyond this — even beyond the porcupinefish’s ability to puff up.

Have a look: http://youtu.be/JtgEtUIu4Q0

How striking that the second fish hovers so closely near the trapped one, even as the humans intercede! This, I think, is why the video has more than half a million views on YouTube.

The snorkelers were associated with Core Sea, the group devoted to marine research and conservation that first posted the video, filmed March 20.

I reached out to Core Sea this week in search of some details. For instance: Is the fish that was trapped a male and his companion a female, as I strongly suspect? I haven’t heard back.

What I do know is that this species (Diodon liturosus) is the black-blotched porcupinefish. Not only can these fish swallow water and raise their spines to make themselves look bigger and fiercer, but they also harbor in their bodies a neurotoxin that contributes to self-defense.

Jonathan Balcombe, author of many books on animal behavior and emotion, including the forthcoming What a Fish Knows: The Inner Lives of Our Underwater Cousins, had this to say:

“This touching video shows virtuous behavior in two distantly related vertebrates. A porcupinefish bravely keeps vigil for his entrapped comrade, while a kindhearted snorkeler gingerly negotiates the situation with an improvised cutting implement — the bottom of a broken bottle.

“A skeptic might think the bystander fish is just curious, but if that were the case, the fish would have fled the scene when the large ape approached. Like many fishes, pufferfishes (of which the porcupinefish is a member) can live a decade or more and can form lasting bonds with others of their kind or with human caregivers.”

Increasingly, animal behavior researchers recognize lasting bonds in animals beyond mammals and birds. Animal friendship is a real phenomenon. For my definition to apply, we would have to see these two porcupinefish hanging around together for a while before invoking “friendship.” If they stay close together only during mating, then separate — which according to my reading is a probable explanation — then their filmed togetherness wouldn’t qualify as a friendship.

But it would qualify as a strikingly close bond, and as yet more evidence that fish have a lot of fascinating things going on in their lives.

Barbara J. King

Originally published here: http://www.npr.org/sections/13.7/2016/03/31/472500225/popular-video-of-porcupinefish-rescue-hinges-on-his-companion

Posted April 4th, 2016.

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Fish With Rainbow-Colored Cells Shows Scientists How Skin Heals Itself

Rainbow Fish

https://www.sciencedaily.com/videos/78d4b6342727b4b791b38bc563ab45b2.htm

The genetically modified zebrafish, aptly named “skinbow,” could go on to help scientists understand how skin reacts to medications or disease.

Video provided by Newsy

Posted March 22nd, 2016.

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R.O.E. (Real Oceanic Eggs™) – For Fish and Invertebrates

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R.O.E (Real Oceanic Eggs™) – For Fish and Invertebrates

A Reef Nutrition® feed for fish, LPS & NPS Corals, & other invertebrates such as Anemones, Zoanthids & Palythoa. Super-concentrated, marine fish eggs harvested from cold water fish in the North Atlantic Ocean, the source of the richest nutrients. Unique Benefits: richest in natural fatty acids of all roe products, no coloring agents; intact eggs means all nutritional value is available to aquarium animals; easily dispersed; longest shelf life of any refrigerated, marine-sourced roe product. www.ReefNutrition.com

 

Posted March 17th, 2016.

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Scientists have discovered a ‘ghostlike’ octopus in deep water off Hawaii

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Scientists have discovered a ‘ghostlike’ octopus in deep water off Hawaii that appears to belong to a previously unknown species, researchers said. Video provided by AFP

http://www.sciencedaily.com/videos/74654ce35bd4e497e6197fd838608b4c.htm

Source: Scientists have discovered a ‘ghostlike’ octopus in deep water off Hawaii that appears to belong to a previously unknown species, researchers said. Video provided by AFP

Posted March 7th, 2016.

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Captive breeding could transform the saltwater aquarium trade and save coral reefs, biologists say

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Dr. Joan Holt is the associate director of the Fisheries and Mariculture Lab at the University of Texas at Austin Marine Science Institute in Port Aransas. She’s done pioneering work in the field of marine aquaculture, and has helped launch a movement to change the way that fish are raised and sold for saltwater fish tanks.

Credit: Scott Holt

Marine biologists at The University of Texas at Austin Marine Science Institute are developing means to efficiently breed saltwater aquarium fish, seahorses, plankton and invertebrates in captivity in order to preserve the biologically rich ecosystems of the world’s coral reefs.

These scientists believe their efforts, and those of colleagues around the world, could help shift much of the $1 billion marine ornamental industry toward entrepreneurs who are working sustainably to raise fish for the aquarium trade.

“It’s the kind of thing that could transform the industry in the way that the idea of ‘organic’ has changed the way people grow and buy fruits and vegetables,” says Joan Holt, professor and associate chair of marine science at The University of Texas at Austin. “We want enthusiasts to be able to stock their saltwater tanks with sustainably-raised, coral-safe species.”

Holt is a co-author of a recent article, “Advances in Breeding and Rearing Marine Ornamentals,” published in the Journal of the World Aquaculture Society in April.

The paper is a complement to Holt’s broad-ranging work over the past 10 years to promote captive breeding of ornamentals. She’s been a pioneer in developing food sources and tank designs that enable fragile larvae to survive to adulthood.

Holt has also been a vocal critic of the extraordinarily wasteful methods currently used to bring sea creatures from the oceans to the tanks.

“One popular method is to use a cyanide solution,” says Holt. “It’s squirted into the holes and crevices of the reef and it anesthetizes the fish. They float to the surface. Then the collectors can just scoop them up, and the ones that wake up are shipped out.”

This method, says Holt, has a number of unfortunate effects. It bleaches the coral. It kills or harms other species that make the coral their home, particularly those that can’t swim away from the cyanide. It can deplete or distort the native populations of the species. And it contributes to 80 percent of traded animals dying before ever reaching a tank.

Unlike the freshwater ornamental market, which relies mostly on fish raised in captivity, the saltwater ornamental market is 99.9 percent wild caught. Holt says this is largely because there’s less accumulated knowledge on breeding saltwater fish in captivity. Saltwater species also tend to spawn smaller, less robust larvae, which are harder to rear to maturity, and to rely on various foods, such as plankton, that are not readily available in mass quantities for breeders.

Yet all these difficulties, says Holt, are surmountable.

She and her colleagues in Port Aransas, where the Marine Science Institute is located, have successfully bred in captivity seven species of fish, seahorses and shrimp they’ve caught from the Gulf of Mexico and the Caribbean, including species that other biologists had tried but failed to rear before. Others have successfully bred popular species like clownfish, gobies, dottybacks, and dragonets, as well as coral, clams, invertebrates, and algae.

Several big aquariums, including SeaWorld, have committed to assisting in the breeding and egg collection effort, and to integrating into their exhibits information about how the aquarium trade impacts the coral reefs.

Holt and her colleagues envision, ultimately, is a “coral-safe” movement. The science, the economics and the social awareness could together result in a sea change in how saltwater aquariums are populated and how saltwater tank enthusiasts think of themselves and their passion.

As more tank-raised ornamentals percolate into the market, Holt believes people will see another advantage to buying sustainably. The fish will simply do better. They’ll live longer, be healthier and be easier to care for.

“Species that are bred in captivity should adapt much better to your tank than something that was just caught halfway across the world, in a different system,” says Holt. “Good retailers will want to sell these species, and consumers will benefit from buying them.”

Source: University of Texas at Austin

Posted June 2nd, 2015.

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Breeding Common Fish

By Mike Hellweg

As promised, I spent some time in a couple of local big box stores and a couple of local fish stores. In both big box stores the pickings were mighty slim for me— mostly big fish like cichlids. But there were a few nice small fish from which I selected some potential breeding stock.

The local fish stores were even better. I was able to go into one and find several pairs of tetras and barbs that were old enough for spawning. Even better, in one I was able to get them all on sale at a huge discount! And in the other, I was able to trade a bunch of young fish from the contest for several pairs and a couple of breeding groups that were almost ready to go. This illustrates one of the great reasons to support your local shop—I was able to trade in some of my breeders to one local shop and get a couple more species in exchange.

So in a couple of hours, with a couple of stops, spending only about $25, I re-homed a large number of fish and brought home enough fish to keep me busy for at least a couple of weeks in the contest.

Obviously, all of the fish, even those I get from friends, go into quarantine first. No sense introducing disease into an established tank.

Here are some of the fish I found:

Cichlids:

Pseudocrenilabrus philander

Livebearers and Killies:

Wild-type green swordtails Xiphophorus hellerii

Coral red platies Xiphophorus sp. domestic platy

Sunset variatus Xiphophorus sp. domestic variatus

Catfish:

Corydoras narcissus (marked as skunk cories – Corydoras arcuatus)

Corydoras paleatus

Egg Scatterers:

Pearl danio Danio albolineatus – these were on sale for just 11 cents each!

Zebra danio Danio rerio – 11 cents each!

Blue danio Danio sp. – 11 cents each!

Fireline danio Devario sondhi

Black skirt tetra Gymnocorymbus ternetzi

Silvertip tetra Hasemania nana

Glowlight tetra Hemigrammus erythrozonus

Head and tail light tetra Hemigrammus ocellifer

Pretty tetra Hemigrammus pulcher

Ember tetra Hyphessobrycon amandae

Columbian redfin blue tetra Hyphessobrycon columbianus

Sickle fin tetra Hyphessobrycon robertsi

Serpae tetra Hyphessobrycon serpae

Neon tetra Paracheirodon innesi

Tiger barb Puntius anchisporus

Melon barb Puntius melanampyx

Black ruby barb Puntius nigrofasciatus

Gold barb Puntius semifasciolatus or Puntius “sachsi”

White cloud mountain minnow Tanichthys albonubes

Penguin tetras Thayeria obliqua

Anabantoids:

Honey gouramis Colisa chuna

Pearl gouramis Trichogaster leeri

Gold gouramis Trichogaster trichopterus

Marine Fish:

Tank Raised Bangaii Cardinals Pterapogon kauderni

And a group of spotted loaches – no idea what species they are but they are easily sexable, so I’ll keep my fingers crossed!

Since Ted mentions it, I’ll stress again how important quarantine is to success with aquarium fish. Several of the neon tetras and fireline danios came down with ich soon after arriving home. It is likely the cold weather somewhere in transit, either at the airport here before they made it to the shop, or in the delivery truck stressed them and made them susceptible. Fortunately, I followed my normal procedure and put the new fish in quarantine tanks. The ich only affected two of those tanks. I was able to treat it immediately since I was watching for it, and only lost a couple of fish. The rest came through with flying colors. Of course this sets any breeding attempts with those two species back several weeks as they will need time to recover. But I’ve got plenty of fish to work with for the next few weeks.

Posted June 2nd, 2015.

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Sneaking Success

Neolamprologus pulcher. Photograph from TFH Archives.

By David E. Boruchowitz

Cichlids demonstrate extremely sophisticated reproductive strategies. One of the least common involves cooperative breeding in groups or colonies. Lake Tanganyikan Neolamprologus pulcher breed en masse, with the entire colony rising as one to fend off predators, and with non breeding individuals participating in the care and protection of the offspring.

Aquarists have long known about this behavior, which is more obvious in the wild, where hundreds of fish are involved, but which translates in captivity into breeding groups that avoid the typical predation on the fry by non parental adults in the same tank.

A new study reveals that about 10 percent of the fry produced in these colonies are sired by subordinate males, and that those males are more diligent in protecting the young.

http://www.sciencedaily.com/releases/2011/10/111012185628.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29

This is reminiscent of the situation in several Xiphophorus swordtails, where smaller, inconspicuous males rely on sneaking rather than courtship to father a small percentage of fry. In both cases subordinate males father a small but significant number of offspring, though in the case of the swordtails it is a matter of genetic castes among the males, not just one of dominance.

Posted June 2nd, 2015.

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Colony-breeding Cichlids Finally Come Through

By Ted Judy

Twenty years ago I kept and bred a lot of Lake Malawi cichlids.  It is hard to beat the riot of color in a well-stocked Malawi community.  Matthew (my 7-year-old fish fanatic in the making) discovered this colorful genre about a year ago, and has been slowly taking over tank space in the house ever since.  We are up to three Malawi community tanks: a 42-gallon bow front in Matthew’s room, a 55-gallon in the family room, and a 40-gallon breeder in the fish room.  I decided to take advantage of these three tanks for the contest by converting the tanks from purely aesthetic communities into breeding colonies.

What is the difference between a community and a breeding colony?  A community can be any mix of fish regardless of sex ratio, age and compatibility (though I would hope they all can get along).  A breeding colony is a group of fish set up to encourage breeding.  There is some cross over.  Purists and serious breeders will usually set up single-species colonies with only one or two males and many females.  These large colonies will usually produce a lot of fry, but only of one species.  Matthew and I chose to sacrifice large numbers of fry in hopes of getting multiple species to breed in the same tank.

The trick is to set up groups of fish that are compatible, but are not so similar that hybridization is likely to occur.  Luckily there are so many different Lake Malawi cichlids that finding a good mix is not too hard to do.  The two main breeding tanks are the 42-gallon bow front and the 55-gallon.  The 40-breeder in the fish room has one species old enough to spawn (Labeotropheus trewavasae “Mphanga”) and a bunch of young fish that are growing up to be the next groups to go into the spawning tanks.

Labeotropheus trewavasae Mphanga.

Labeotropheus trewavasae “Mphanga.”

The 42-gallon tank has a quad (one male  and three females) of adult Aulonacara stuartgranti ‘Ngara’ peacocks, a trio of Metriaclima sp. “white top Hara” and a trio of the electric blue “johanni” Melanochromis cyaneorhabdos.  We had to get rid of a few single males of different species and find some females to fill out the colonies.  We also added a lot more hiding places, which we did very inexpensively by asking the local plant nursery for any large damaged flower pots.  Matthew is very good at getting free broken pots, which we broke more until they would fit in the tank.  A big pile of the curving terra cotta pieces is perfect for these cichlids.

Aulonacara stuartgranti Ngara.

Aulonacara stuartgranti “Ngara.”

The 55-gallon has a quad of large  OB Labeotropheus fuellebourni, a group of eight (two males, six females) Metriaclima sp. “Msobo,” and a trio of Pseudotropheus sp. “red cheek.”  I am a little concerned about hybridization between the Pseudotropheus and Metriaclima, but I have not seen any evidence of it happening.  In my experience, if there are suitable mates of the same species for all the fish in the tank hybrid breeding rarely occurs.  I will hope for the best and pay careful attention to the fry.

Labeotropheus fuellebourni; offering a suitable number of mates of the same species is often a good way to prevent hybridization.

Labeotropheus fuellebourni; offering a suitable number of mates of the same species is often a good way to prevent hybridization.

Metriaclima sp. Msobo; pay careful attention to the colors and patterns on the fry to check that hybridization has not occurred.

Metriaclima sp. “Msobo”; pay careful attention to the colors and patterns on the fry to check that hybridization has not occurred.

The colonies were set up before the contest started, but we only had one species spawn right away: Metriaclima sp. “Msobo.”  Nothing else spawned in the next two months.  I started feeding more heavily and doing large water changes more frequently.  Once every two weeks I would do a really large water change followed by a 4-day fast.  Sometimes the lack of the diversion of food will trigger fish to spawn.  The weather started to get cooler, and that is not conducive to getting Malawi fish to breed, so I was worried that I would not see any success until spring.  So the first week of December I added a big heater to each tank and jumped the temperature up to 82F in hopes of heading off a winter lull.  I normally do not keep my tanks much above 74F.  I believe that cooler water is better for the health of the fish (assuming the fish are not ‘hot water’ species).  I also went out onto my local club’s forum and asked for advice.  Everyone said to split the communities up and go back to one species per tank.

I was about to do that when everything started to spawn.  Within three days we had holding females of the L. trewavasae “Mphanga,” L. feullebourni, A. stuartgranti “Ngara,” Melanochromis cyaneorhabdos, and Metriaclima sp. “white top Hara.”  Five out of seven is not bad, and since the M. sp. “Msobo” spawned early in the competition we are left with only one species of breeding-age Malawi cichlid to spawn.

The plan now is to rotate the species that have spawned out and new species in.  Matthew is excited… he LOVES to shop for fish (the apple does not fall far from the tree).

Posted June 2nd, 2015.

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A Basic Strategy for Spawning Tetras, Barbs and Danios

By Ted Judy

There are many species of tetras, barbs and danios that are not difficult to spawn.  A good rule of thumb to figuring out a species’ difficulty is to compare prices at a fish store.  Fish that are common and inexpensive are most often farm raised and easy to breed.  The poster-fish for this group is the zebra danio Danio rerio.  There are two challenges for the hobbyist breeder when working with these species.  First, collecting the eggs can be impossible if the breeding tank is not set up to catch eggs.  Second, raising the very small fry can be a challenge without the right foods ready when they are needed.

I breed most of the tetras, barbs and danios in 2.5 gallon tank.  When the fish are very small, and lay a lot of eggs, I usually put a lot of yarn mops in the tanks.  After a few days the fish have deposited plenty of eggs in the yarn.  Some will get eaten, but there are enough hidden in the mops to meet my modest requirements (I do not really need or want more than a dozen fry).  Larger species tend to be better at eating their eggs, so I use a false bottom in the tank made from a piece of plastic needle-point mesh cut to fit into the 2.5-gallon tank.  I cut the screen so that it drapes in the bottom.  I use a couple pieces of PVC to hold the plastic off of the glass.

A spawning mops hides the eggs from the parents so they do not get eaten.

A spawning mops hides the eggs from the parents so they do not get eaten.

Creating a false bottom using a screen is another way to separate parents from their eggs, and works best with larger species that tend to eat eggs off the spawning mop.

Creating a false bottom using a screen is another way to separate parents from their eggs, and works best with larger species that tend to eat eggs off the spawning mop.

Once the screen is in place I add plants or yarn as a place for the fish to spawn.  The eggs filter through the plants and then fall through the plastic mesh.  Since the bottom of the tank is bare the eggs easily seen.  After the eggs are laid I remove the fish, screen and pvc.  I leave the plants and add a drop or two of methylene blue.  I cover the top of the tank with a piece of cardboard to block the light.  Most species’ eggs hatch in less than three days, and the fry are ready to eat a day later.

The first food I use is paramecium.  If you do not have a paramecium culture there are products on the market, called fry foods, which are designed to provide small particles for baby fish.  A good supplement to a food product is ‘sponge grunge’.  Squeeze a well established sponge filter into the tank with the fry and some plants.  The microorganisms in the sponge will start a colony that will feed to fry.  After a few days the fry can eat microworms.  One trick I use is to keep my microworm cultures very wet, about the consistency of a thick soup.  The media in the culture contains all different sizes of the nematodes.  When I feed from the culture, I scoop a little of the media onto my finger and swirl it into the tank with the fry.  Yes, it clouds the water… but the fry do not care, and they are getting very small food.

After a week most fry can eat baby brine shrimp and they are off to the races.  With lots of food and frequent water changes they will grow fast.

I have ten 2.5-gallon breeding tanks in my fish room.  From spawn to relocating the fry to a growout tank tanks about 10 – 15 days.  If everything works out perfectly I could breed 20 – 30 species of ‘easy’ tetras, barbs and danios in thirty days.  Plans rarely work out perfectly, however, and I am happy to be successful with 5 – 10 successful spawns each month.

Posted June 2nd, 2015.

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