Archive for August, 2009
Feeding Canned and Live Insects to Marine and Freshwater Fishes – Part 2
Aug 31st
Hello, Frank Indiviglio here. I have always included insects in the diets of a great many fishes, including shallow-water marine species (in the accompanying photo, you can see a number of typical community aquarium species swarming around a cricket). Please see Part I of this article for further information on the role of insects in marine and fresh water fish diets.
My Experience with Wild Fishes
Whenever I have the opportunity, I toss insects into natural water bodies. Time after time, be I near a quiet pond in Ohio or a salt marsh on Long Island, the insects never last more than a few minutes before being consumed by resident fishes. Eventually, I came to believe that terrestrial invertebrates play a great role in the diets of numerous freshwater, brackish and even marine fishes (many insects fly far out over the ocean, especially on migrations, or are carried there by the wind).
Current Research
Just this month (August, 2009), biologists at the National Oceanographic and Atmospheric Administration published the results of a research effort which addressed this very topic. Surveys of fishes in lakes across North America have revealed that terrestrial insects comprise up to 100% of the diets of some fish species (my own casual observations are rarely validated in such a timely fashion!).
However, in lakes where development has eliminated shoreline vegetation, insects typically make up only 2% of the diets of the same fish species. The importance of insects is evidenced by the fact that fishes living in lakes with developed shorelines take in 50% less energy on a daily basis and grow slower than those in undeveloped lakes. Fortunately, re-planting even a narrow fringe of bushes and grasses along a lake can dramatically increase terrestrial insect populations.
Canned Insects for Aquarium Fishes
Both live and canned insects are eagerly accepted by many typical (and untypical!) aquarium fishes. Canned invertebrates may be better suited for most aquarists, who, unlike their reptile-keeping colleagues, are not often in the habit of maintaining live insect colonies. What’s more, they retain all the nutrition of live insects but are far more convenient to store and use.
Canned grasshoppers and adult crickets are ideal for large carnivorous fishes such as Oscars and other Cichlids, arowanas and many catfishes, and can also be crushed or chopped for smaller species. Other varieties of canned invertebrates include snails, mealworms, silkworms and young crickets . Freshwater shrimp , also available in cans, are eagerly taken by a wide array of fishes.
Further Reading
In some habitats, the availability of “junk food” is reducing the role of insects in fish diets. To learn more, please see http://www.sciencedaily.com/releases/2004/09/040928101517.htm.
Please write in with your questions and comments. Thanks, until next time, Frank Indiviglio.
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Loading ...That Fish Place Aquariums and Fish Recap – Week of 8/24
Aug 28th
Ah, Friday. Best day of the week! Though there is never a lack of interesting fish/aquarium/ocean related news to reinvigorate us and carry us through. Let’s take a look at the news and newbies!
The Grunion are running! AHHHHH! Actually, if you don’t know what grunion are and you’re concerned about why they are running, don’t worry, it’s actually a good thing. This might be something I would put on my bucket list of things to experience before I die. (I’m easily amused.) http://www.al.com/newsflash/index.ssf?/base/national-19/1250767015290200.xml&storylist=national&thispage=1
If anything could be more exciting than the running of the grunion, check out the image captured by Google earth!!! I always knew she was there somewhere, not even Nessie can escape the spying eyes in the sky! http://www.guardian.co.uk/theguardian/2009/aug/27/loch-ness-monster-google-earth
Everybody has an opinion on goldfish in the aquarium world, and sadly, the opinions are not always good. But when you see those bulging eyes and that bobbing, bulbous body, its hard not to smile. In case you didn’t know already goldfish do have some redeeming qualities, and they may be cause to consider them again as a new family pet. http://www.dailymail.co.uk/news/article-1209316/Gulp-Why-life-goldfish-bowl-lot-exciting-thought.htmlhttp://www.chucksaddiction.com/hitchworms.html
We get questions all the time from customers about something that emerged from their live rock or from a coral or from seemingly nowhere. Strange worms are often a fact of life in reef aquaria, and though you may not always see them, chances are there are some hiding away in the dim recesses of your rock. This little gem might help you ID or at least get closer to IDing the little surprises that come along with reefing.New and exciting this week at TFP:
Check the blog for pics of these guys.
We got a Cave Bass this week! These guys aren’t available often but they are super neat. They’ll tend to hide out in shadowy caves in your tank, but you’ll be pleased just to know he’s there. (No Ratings Yet) Loading ...African Oddities – the Bichirs and Reedfish
Aug 26th
Hello, Frank Indiviglio here. I have always favored fishes that seem to straddle the line between the fish and reptile/amphibian kingdoms. Included among these are both marine and freshwater forms, including the toadfish, frogfish, lizardfish, lungfish, mudskipper (note the common names!) and others. The freshwater fish family Polypteridae, containing the bichirs and the reed or rope fish, has long fascinated me and seems very popular with visitors to the exhibits I have worked on at the Maritime Aquarium (Norwalk, CT) and the Bronx Zoo.
Few if any bichirs have been well-studied, and even the most commonly available species are rarely bred in captivity; much can be learned by the patient aquarist.
Description
The dorsal fin rays of these elongated, snake-like fishes are separated from one another, rising and falling in a series of humps and lending them the appearance of scaled-down dragons. This effect is most evident in the aptly named Senegal dragonfish (please see below). The pectoral fins are rimmed with fleshy lobes, and are paddle-like in shape and function.
Swimming takes the form of short bursts, but mainly these fish scull along the bottom. The largest, including the commonly sold reedfish, can reach 3 ½ feet in length, but most are considerably smaller. Although dissimilar externally, bichirs are believed related to sturgeons, paddlefishes and gars.
Range and Habitat
Bichirs are limited in range to tropical Africa and the Nile River system, and are usually associated with shallow, plant-choked waters such as marshes, swamps and the shores of slow-moving rivers.
Future Amphibians?
The amphibian-like qualities of the bichirs are not limited to appearance alone. The swim bladder has evolved into an accessory breathing organ, allowing them to breathe atmospheric oxygen and to survive out of water for some time…few species are rumored to voluntarily leave the water for short periods. The young of some species even sport external gills, much like salamander larvae!
Reed or Rope Fish, Erpetoichelys calabaricus
This brown West African native has a sinuous, snake-like body and a wide mouth. The reedfish hides under the mud by day, emerging at night to feed upon insects, fishes, worms and frogs. It can reach a length of 3 ½ feet, but rarely attains that in captivity.
Senegal Dragonfish or Cuvier’s Bichir, Polypterus senegalus
Rounded, widely-separated dorsal fin rays lend the Senegal dragonfish an uncanny resemblance to its mythical namesake…it really does look like a miniature dragon!
Senegal dragonfishes are distributed throughout the Congo Basin and reach 12 inches in length. They make hardy, interesting aquarium pets and often learn to anticipate feeding times. The effect of a large specimen in a well-planted aquarium is quite spectacular – they definitely deserve more attention from aquarists.
Ornate Bichir, Polypterus ornatipinnis
Swamps and marshes in West Africa are the home of this commonly imported bichir. Patterned with a lacework of black markings, the ornate bichir is one of the more attractive members of its family.
Unfortunately, due to its unique appearance, the ornate bichir is often purchased on a whim. Few realize that the youngsters sold in pet stores eventually grow to 18 inches in length, and are often aggressive towards tank mates. However, properly accommodated ornate bichirs make fascinating pets, and, as they are rarely bred in captivity, are ideal species to study.
Further Reading
You can read more about bichirs, and see a list of all recognized species, at http://www.fishbase.com/NomenClature/ScientificNameSearchList.php?crit1_fieldname=SYNONYMS.SynGenus&crit1_fieldtype=CHAR&crit1_operator=EQUAL&crit1_value=polypterus&crit2_fieldname=SYNONYMS.SynSpecies&crit2_fieldtype=CHAR&crit2_operator=contains&crit2_value=&group=summary&backstep=-2.
I’ll address captive care in more detail in the future. Until then, please write in with your questions and comments. Thanks, until next time, Frank Indiviglio.
Polypterus senegalus image referenced from Wikipedia and originally posted by Zhyla
Rope fish image referenced from Wikipedia and originally posted by Michael Zalewski
(No Ratings Yet) Loading ...Aquarium Fish Growth Myths
Aug 24th
Eileen here. Some myths and legends are universal. Almost every country has some version of a “bigfoot” legend. Nessie is one of Scotland’s biggest celebrities. People are abducted by aliens and UFO’s are spotted in the sky around the world. What does the aquarium hobby contribute to this list?
“Fish only grow to the size of their aquarium.”
Like most of those other stories, this one likely started because people saw some truth behind it. They saw their fish grow large in relation to their aquarium, stop growing, then die. But, just like we now know that the Earth is not flat and we will not fall off the edge of it if we sail too far, we now know that the size of an aquarium does not dictate the size of a healthy adult fish.
The most common victim of this theory is the comet goldfish, the fish often sold as very inexpensive feeder fish or won in carnival ping-pong ball toss games. People win the fish or buy them as inexpensive pets, not knowing that the tiny fish they took home should be able to become an 8-10 inch adult with a lifespan of 10 years or more if well cared for. “Goldfish bowls” are sold almost everywhere that carries fish supplies. Small aquariums – 10 gallons or under – are often sold with pictures of small fancy goldfish on the box so it is no wonder that people may be unaware of the problems they are walking into.
Keeping any animal, fish or otherwise, in a habitat that is too small for it causes a number of problems that might not be obvious at first. The fish people win at carnivals or purchase as small juveniles might be fine for a short time in a small aquarium, but as the fish grows, so does its requirements. Looking at the same situation in terms of a person instead of a fish, it becomes more obvious. An infant, for example, doesn’t require much space for his needs to be met. He can feed and exercise within the area of his nursery and regular cleanings can keep his nursery healthy. But, as the infant grows into a toddler, his needs also grow. He requires more space to exercise so his muscles develop properly. He is growing and needs more food and so produces more waste as a result that the same regular cleanings the infant received cannot control. As he grows through his life, that boy can certainly grow into a man if never let out of the nursery that he was kept in as an infant, but that man will not be as healthy as he could be. His hygiene and development will have suffered from being kept in a confined space and not allowed to flourish and develop properly and he will probably not live as long as a man whose environment has been allowed to grow with him.
The same happens when a fish is kept in a small tank. As the body of the fish grows, so does the amount of waste it produces and the food it needs. This can affect the water quality of the aquarium and lead to disease caused by high ammonia levels, high nitrite levels, low dissolved oxygen content, low pH and other incorrect parameters. Just as a person kept in a small space cannot grow properly, the fish would also physically not be able to grow to its full size. Its body and skeletal structure may be stunted by the lack of space and ability to exercise and swim as it should, but the internal organs often continue to grow at a normal rate. The internal damage this causes, in combination with water quality issues, will lead to a premature death.
While a small tank can certainly affect the size of the fish, it is not the way that we once believed. There is no internal sensor in a fish that can detect the size of its environment and adjust its growth accordingly. The fish we keep are just as dependent upon us as small children to give them the proper care needed to keep them healthy so it is up to us to be aware of what their needs are and to do our best to make sure those needs are met throughout the fish’s life.
(+3 rating, 5 votes) Loading ...That Fish Place Aquariums and Fish Recap – Week of 8/17
Aug 21st
Patty here, and welcome to our Friday recap. Lots of fun and interesting stuff crop up both worldwide and right here at TFP over a week’s time, so we’ve decided to start hooking you up with sweet updates on these kinds of things. Be sure to let us know what you think of these posts (The little thumbs up, thumbs down at the bottom), and feel free to send us some of the excellent things you’ve read in the comments or on Facebook.
This week’s Noteworthy Fish stuff
http://www.macna2009.com/
The results of our first cross-Facebook/Fish Catalog photo contest are in, and Michael S. from McConnellsburg, PA is the winner with this sweet pic of a Black Misbar and a Derasa Clam. Michael will receive a $100 gift card, and have his photo featured in the Fall fish catalog. Check out Michael’s picture here, and if you’re interested in entering for the Winter Fish Catalog, send your high-res photo to petsonline@thatpetplace.com.Cool new stuff at That Fish Place this week
You can see where the Spanish Shawl Nudibranch gets its name, flamenco anyone? Very cool but they are specialized feeders like many other nudis!
This Hawaiian Cultured Blue Maxima is A-mazing!
Two sweet War Coral Frags…Get them while they’re here!Just a sampling, come see us and check out these and tons of other cool stuff!
Until next time,
Patty
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