Overgrowing Pond Plants and Invasive Species

It’s starting to get warm. Really warm in the U.S. And, for many of you, you’re starting to notice your pond plants are starting to kick it into overdrive.

Pond Plants, more than most other plants in my opinion (probably because they always have access to water) can really kick into growth once the water temperature goes up. I’ve been one of the folks who literally starts throwing  away the water hyacinths I paid 4 bucks for a few months earlier because I have no where to go with them. I’ve seen the dwarf moneywort in my pond run out of room within and establish itself OUTSIDE the pond. Even hardy pond lillies, while beautiful, can go to town in a mud bottomed pond.   

It is these rapidly growing plants which form some of the most environmentally invasive species available. Imagine, what’s happening in your pond allowed to carry on unabated in a large lake? Unless you can properly dispose or trade them, do not introduce them back into the wild. The threat of serious ecological impact is particularly strong from these seemingly unstoppable plants.

Many local garden clubs or websites will be happy to share and swap out plants with you. You may even be able to pick up a new species or 2 for your water garden. As in all things, consider the impact before you act…..

For more information on invasive plant species within the US, check out invasivespeciesinfo.gov.

Freshwater Stingrays: Points to Consider Before Your First Purchase

Hello, Frank Indiviglio here. Stingrays – mysterious, beautiful and odd – are difficult to resist, and therein lies their main drawback as aquarium fishes. While not particularly delicate, experience with other fishes does not always serve one well where stingrays are concerned. Their husbandry is not well known, and there are a number of special considerations which must be borne in mind.A marine species (the little skate, Leucoraja erinacea) was the first ray to catch my attention. I was about 7 years old, prowling the stalls of NYC’s famous Fulton Fish Market in the pre-dawn light. Accompanied by my grandfather, we were seeking new pets – octopus, turtles, eels and such – that rarely appeared in pet stores at the time. The skates, while living, were in bad shape, but I vowed to give them a try someday. Eventually, freshwater rays appeared in Manhattan aquarium shops, and I was off and running.

Following are some points to consider before purchasing your first freshwater stingray. Having a handle on these matters beforehand will greatly increase your chances of succeeding with these spectacular fishes.

Medical Precautions
Stingrays are venomous animals. While no freshwater species are known to have caused human fatalities, we know very little about the nature of the toxins they produce, and individual sensitivities may be a concern.

Speak with your doctor and arrange for medical care in the event of an emergency before purchasing a stingray.

Selecting an Individual: Size
The small stingrays that appear in the pet trade are not adults but rather are babies of a variety of large species. Even those sold as “teacup rays” will reach at least 18 inches in diameter when mature (2-3 years), and will require a tank measuring 4′ x 2′ x 2′ if they are to thrive. Adults of several trade species approach 3 feet in diameter.

Furnishing the Aquarium
Stingray skin is easily damaged by ornaments that are safe for other fishes; they do best in a sparsely-furnished aquarium. Even small specimens will quickly uproot plants and dislodge filter tubes, aerators and heaters.

Use smooth stones as a substrate. Typical aquarium gravel is too rough and may cause skin lesions. Substrates designed for marine aquariums raise the pH to dangerously high levels and sand, while acceptable, poses water quality problems (please write in for further details).

Stingrays often alight upon aquarium heaters, but seem not to respond to the high temperatures generated. Heaters must always be shielded by a PVC sheath or heavy rocks.

Personal Observations in the Field
While on a field research assignment in Venezuela, I was happily situated within the range of 4 species of freshwater stingrays. The animals spread out onto the flooded grasslands during the rainy season, and were rather easy to find.

The largest individual I observed was dead and floating down the Orinoco River. Spanning nearly 4 feet across, it easily supported the weight of the black vulture that was feeding upon its carcass.

A Hands-On Experience with Stingrays
Please be sure to visit That Fish Place/That Pet Place in Lancaster, PA (the world’s largest pet store) for a chance to hand feed our friendly marine stingrays.

More to follow next week. Until then, please write in with your questions and comments. Thanks, Frank Indiviglio.

Further Reading
Please check out the book Freshwater Stingrays.

An interesting article on the conservation of South American stingrays is posted at http://www.cites.org/common/com/ac/20/E20-inf-08.pdf.

Image referenced from Wikipedia and originally published by Raimond Spekking.

Fish Geek TV – River Monsters

So there are those of us out there that find ourselves channel surfing on a Sunday night in a desperate attempt to find something worthwhile to watch. I usually turn to the educational /animal/nature side of things, History, Discovery, you know, not just mindless drivel that pollutes the airwaves. A few weeks ago, I came across a fun series on Animal Planet, and as a “fish geek” I became captivated.

The show is called River Monsters, and if you haven’t seen it you may want to check it out. It may not be up the level of Blue Planet or Planet Earth, but it does capture some amazing footage of the host catching and releasing some of the more monsterous (if not in behavior, certainly in size) fish in the world’s rivers and lakes. These are the kind of fish that inspire Sci-fi writers!

Being in the business, I am familiar with most of the species the host, angler Jeremy Wade seeks out, but it is pretty amazing to me to see adult specimens alive and in their native habitat from the comfort of my sofa. Some of these fish are even common imports, and the show is great proof that most home aquariums are not and will never be large enough to accommodate such species comfortably, a whole new meaning to “this fish gets big.” If you’re looking for some entertainment on Sunday night, check it out, or take a look at the site:

And check out “Natures Most Amazing Events” on Discovery if you like the Blue Planet and Planet Earth series.

Hands-On Volunteer Opportunities in Native Fresh Water Fish Conservation

Hello, Frank Indiviglio here.  Involvement in exciting and important conservation work need not be limited to those select few fortunate enough to have turned their hobbies into careers.  Especially in today’s economy, many vital research and recovery efforts rely heavily upon the work of volunteers.  Getting out in the field (or pond, river and swamp, as the case may be!) is a wonderful way of expanding your fish-keeping horizons.  Today I’d like to focus on fresh water species; I’ll cover marine fishes in the future.

Conserving Desert-Dwelling and other Rare Fishes

The North American Native Fish Association http://www.nanfa.org/ sponsors a number of conservation initiatives, all of which utilize volunteers.  Particularly active in the conservation of desert spring fishes and others in similarly precarious habitats, current initiatives include assisting the US F&W Service in removing introduced plants, fishes, crayfish and bullfrogs from critical Moapa spring fish habitat, training university and government researchers in fish sampling techniques and participating in reintroduction efforts. 

NANFA members also get to indulge their fish-keeping interests, establishing native fish aquariums in schools and nature centers and advising caretakers on husbandry and breeding techniques.

A Wide Range of Field and Captive Care Opportunities

The Native Fish Conservancy maintains an extensive collection of articles on native fishes and fish conservation.  If you are unsure of where to start, a review of these would be invaluable in jump-starting the process and providing numerous options. 

Through their “Adopt-A-Tank” program, NFC members also help schools set up and maintain native fish aquariums and assist students in sampling local fish populations…the best of both worlds!

Native Fresh Water Fishes in the Aquarium

Some of our smaller sunfishes have long been popular with aquarists in Europe, but in the USA native fish-keeping is a lost (or barely developed!) art.  I do not quite understand why, as many are interesting, brilliantly colored and little-studied.  Species diversity here is quite high…even over-crowded New York State boasts nearly 150 freshwater fishes, many of which do quite well in captivity (interesting note: more species of fish have been identified in the Amazon River than in the entire Atlantic Ocean!).

North America is populated by a wide variety of gorgeous sunfishes of all sizes (our massive large-mouth bass is, technically, a sunfish).  With colors rivaling those of any tropical species and providing extensive care to their eggs and young, these are, along with yellow perch (please see photo), long-time aquarium favorites of mine.  Another neglected species, the American eel, lived in my collection for 17 years, and a pair of brown bullheads that I bred in an outdoor pond provided a notebook-full of observations that I treasure to this day (males are unbelievably protective of their tadpole-like fry, herding them about for quite some time).

I’ll cover the care of various native fresh water fishes in future articles.  Until then, please write in with your observations, experiences and questions.  Thanks, Frank Indiviglio.

Further Reading

The US Fish & Wildlife Service currently lists nearly 150 species of native freshwater fishes as threatened or endangered.  Information on each, along with links to recovery plans (some of which encourage volunteer participation), is posted at www.fws.gov/endangered/wildlife.html#Species.

The Cold Spring Harbor Fish Hatchery  http://www.cshfha.org/ houses an extensive collection of fresh water fishes, amphibians and reptiles, and is well-worth a visit by native fish enthusiasts.

Dealing with Pond Plant Pests

Patty here.

It’s inevitable. Just when you think your pond is looking its best and all is right with the world, they invade. Aphids, weevils, moths, beetles and others descend onto those beautiful lilies, floaters, and marginals like a summertime scourge.

So what are some solutions to these nasty little pests? Being that your pond is most likely home to other inhabitants like koi, goldfish, frogs and other desirables, you’ll have to consider safe treatments, and the factor will rule out most chemical solutions.

Aphids are one of the most common invaders, sucking the life out of lilies, water lettuce and other soft-leaved aquatic plants. To avoid or minimize their foothold, prevention is the first step. Remove yellowing or damaged leaves from plants, they serve as beacons for the little suckers to home in on. Resist the urge to blast them off of leaves with a hose, as it usually serves more as high speed transport to other plants than as an eradication method. If only a few are present, you may be able to dunk the leaves or pull out putted plants and spray them away from the pond, at least as a temporary fix.
For more serious infestations there are some other methods to consider. You can try natural predator introduction. Ladybugs and green lacewings are natural aphid predators and though you may have a couple of these arrive on their own, you can purchase them online or at many garden centers and introduce them to feast on your pests. Orfes, minnows and guppies may also eat those that you can rinse into the pond. There are increasingly available herbal sprays for pond plants that will not harm fish, but be sure to read labels carefully. These sprays are usually formulated with herbal extracts, so they’re natural and mild, but sometimes too mild to really handle the situation. If you have the means you may even be able to formulate a similar spray by making a strong tea of rosemary, garlic, thyme, chrysanthemum or mint. Some suggest adding a cup of vegetable oil or a dash of dish soap to the mixture as well, but especially in the case of the soap, be sure to spray and rinse the plants well outside of the pond.

Other common pests include mosquitos, Leaf miners, and aquatic moth larvae. Prevention of infestation of these pests consists mainly of good maintenance of the pond and surrounding area, good water movement and the absence of dead leaves and debris in and around the pond. The natural predators mentioned above as well as others like predator wasps and dragonflies that are drawn to flowering plants and water may help, as may the small insect-eating fish mentioned above. Mosquito dunks are effective for the control of many waterborne insects, but they will also affect beneficial water insect larvae, so if you like those dragonflies, they may not be the best option. They are safe for use with fish.
Even though these pests can create a real headache for those of us with a love for aquatic plants, the overall aesthetic and health of a well- planted pond is worth the hassle. If you have any questions about a pest plaguing your water feature or you have a remedy that has worked for you to share, please let us know!

Image referenced from MorgueFile here.