The Natural and Unnatural History of the Koi Pond at the Brooklyn Botanical Gardens

Hello, Frank Indiviglio here.

Brooklyn Botanical Gardens OverviewI have always looked to public aquariums and botanical gardens for inspiration in my own work.  I have visited koi ponds in many places, including some of the famed beauties in Kyoto, Japan (I plan an article on these shortly), but my favorite is, oddly enough, located in the heart of Brooklyn, NY. 

Koi and Cherry Blossoms

The 52-acre Brooklyn Botanical Gardens, opened in 1910, houses a huge, spectacular pond, home to some of the largest and oldest koi to be found anywhere.  The surrounding grounds are planted with 42 varieties of cherry trees, all of which bloom in April and May…seeing this spectacle in combination with schools of colorful koi is an experience of a lifetime (the garden hosts the largest cherry blossom festival, or Sakura Matsuri, to be found outside of Japan).

A rainy spring day many years ago granted me my first look at a koi breeding frenzy…I had previously observed hundreds of carp spawning in the Bronx River, and was suitably impressed (some of these lunkers topped 40 pounds in weight!) but the roiling, colorful koi put their drab ancestors to shame.

An Urban Legend Revealed

I was first drawn to BBG in search of the huge soft-shelled turtles which were said to inhabit the koi pond.  Less cynical than most of my fellow New Yorkers, I had since childhood followed up on any and all reports of urban wildlife, however fanciful.  I had some pleasant discoveries – copperhead snakes did indeed live under the George Washington Bridge and sturgeon still swim the East River, and some disappointments – Flushing Meadow’s “lungfishes” turned out to be American eels.

I found 135 red-eared sliders and several snapping turtles in the pond, but the soft shells eluded me for decades.  Then, while having lunch near the pond (I was working at the nearby Prospect Park Zoo at the time) I spied two huge spiny soft-shelled turtles (Apalone spinifera) basking on a small island.  They remain the largest I’ve ever seen (fish a favorite food!), and must have been living there for upwards of 50 years.  Although native to New York State, spiny soft-shells are quite rare here, and never seen anywhere near NYC. 

Piranha, Osprey and Other Visitors

I enjoy visiting areas that serve as retreats for urban wildlife, and have had many wonderful surprises along the way.  BBG is an important resting place for migrating birds, with over 200 species having been recorded.  The koi pond also yields some surprising visitors from time to time – including “transplanted” bass, sunfish, eels and red-bellied piranha!

Ospreys have made a major comeback in the USA, and are now seen quite near New York and other coastal cities.  Last spring a pair under camera surveillance in Norwalk, CT (The Maritime Aquarium) were regularly observed to bring quite large (and expensive!) koi to their chicks…I’m sure it’s just a matter of time until these huge “fish hawks” visit Brooklyn! 

 Further Reading

You can learn more about the Brooklyn Botanical Garden’s koi pond and amazing plant collection (10,000 species at last count) at http://www.bbg.org/.

Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

A Word About Water Hyacinth

water hyacinchPatty here. Just about anyone with an ornamental pond has either heard of water hyacinth or has a personal experience with hyacinth to share.  I find it to be an interesting and useful plant, and here in PA we don’t have to worry about its invasive tendencies and notorious reputation like those of you in warmer climates.  I thought I’d give a little background on this floater to help you get to know it better.

Water Hyacinth Cross SectionWater Hyacinth (Eichhornia crassipes) is native to tropical South America where it forms vast mats on the water’s surface.  It is sun and heat loving and can reproduce at a ridiculous rate by producing long runners and stolons, which is why it is cosidered a noxious and invasive species in many states and countries.  They can double in population within about two weeks if the conditions are right!

hyacinth root structureIt has unique structure.  Each leaf has a spongy bulb which allows it to float on the surface, and the leaves have a waxy, waterproof feel.  The root system hangs in a long-stranded cluster beneath each plant, and the roots are white to dark purple-brown and very hairy.  These plants also produce beautiful flowers in the peak of summer, a cluster of light purple flowers with six petals each and a violet and yellow accent on the top petal of each flower.

Hyacinth does have its notorious side, and the reputation is well-deserved.  However, in cooler climates, and with responsible management this plant has carved out a valuable niche.  Because hyacinth grows and reproduces so rapidly, it makes a terrific solution to provide shade on ornamental ponds.  Two to three single plants is usually way more than enough to cover a broad area of water surface within a few short weeks, ad it will be necessary to prune the mat to keep the population in check.  The floating mat is a refuge for pond fish and frogs, a food source, and a form of natural, efficient biological filtration. 

The foliage and blossoms are as pretty as they are useful, but the roots are the real prize.  Not only do they provide a surface for fish to deposit eggs, but they serve as a safe haven for fry, tadpoles, and other organisms as they grow.   They have the ability to remove toxins, excess nutrients, and other compounds from the water and have even been used in industrial water treatment applications.  Hyacinth helps to oxygenate, and can even be placed in the filter’s sump as long as there is enough sun!

Hyacinth can be purchased for use in garden ponds in most aquatic garden and pond centers.  We sell it out of our retail location, but do not ship it. It is actually prohibited in many southern states.  If you choose to introduce hyacinth to your pond, don’t overdo it, purchase 2-3 plants, and see how they grow!  Provide them with plenty of sun, and protect the plants from your fish (who will think they are delicious) until they start to reproduce.  And as always, be careful and responsible if you need to dispose of extra hyacinth to ensure that they don’t find their way into natural ponds and waterways.

HR 669 Update

Hi Dave here, just wanted to post an update to Frank Indivigio’s blog about HR 669, the Nonnative Wildlife Invasion Prevention Act.  As many of you know, HR 669 was introduced into Congress this past January, and went to committee hearing on April 23rd.

As I listened to the hearings, it quickly became clear that the committee members had received a great deal of response from both the pet industry and pet owners regarding the bill.  I would like to thank all of those who have read our blog, and contacted the committee members, and those who put a great deal of effort into raising awareness for opposition to HR 669 as it is written.

Click here to actually see footage from within the government offices in deliberation.

Collectively our voices have been heard.  Marshall Meyers, Chief Executive Officer and General Counsel of PIJAC ( Pet Industry Joint Advisory Council), who was present and testified on behalf of the pet industry and pet owners before the committee, stated “It is clear that Committee members from both sides of the aisle heard from the pet owning public about their concerns with this bill.” And that the committee members received thousands of phone calls, letters, and emails from groups and individuals about their concerns over the current form of HR 669.  Meyers added, “We’re extremely grateful to the thousands of groups who galvanized their members leading up to yesterday’s hearing”

Check back with us on our blogs, we will update with any new news regarding HR 669.  And again, thank you for your support in opposition to HR 669

 

Dave

The Asian Shore Crab: Introduced Pest as Aquarium Animal and Food Source

Asian Shore CrabsIn 1988 a small crab showed up on the New Jersey shore, apparently discharged there along with bilge water from ships that had visited the Western Pacific.  Deceptively innocuous, by the mid 1990’s the Asian shore crab (Hemigrapsus sanguineus) was the dominant inter-tidal crab in an area stretching from Maine to North Carolina. In the space of 3-5 years, it became the most common crab at several estuaries that I visit…at one, hermit crabs and sand shrimp have virtually disappeared.

Asian shore crabs seem to co-exist more peaceably with one another than do native species…those pictured here were found under a single small rock.  I wonder if, in contrast to other crabs, newly-molted individuals are not attacked by neighbors. 

Making the Most of an Invader

There is, however, a silver lining to this environmental cloud…the crabs make a nutritious addition to the diets of many aquarium fishes and invertebrates.  Many fishes consume small crabs whole, and they can be broken up for smaller fishes.  Freshwater fishes ranging in size from guppies to peacock bass will enjoy an occasional crab meal as well.

Shore crabs thrive for weeks in damp seaweed under refrigeration and can be frozen for future use.

Collecting Crabs and other Marine Animals

Inshore Lizard FishAsian shore crabs inhabit tide-pools, jetties and salt marshes.  They forage as the tide recedes and are most easily collected at low tide, when they shelter below rocks and other cover.  A wide variety of sizes (please see photo), suitable for nearly any size aquatic pet, can be gathered in no time at all.

While searching for shore crabs, keep your eyes open for shrimps, worms, mussels and other small creatures.  All are useful aquarium foods, and many make very interesting display animals (shore crabs are unprotected, but check local regulations regarding others).

An Unusual Visitor from the South

Seining and setting out minnow traps will improve your catch, and the sea never fails to provide wonderful surprises.  Last summer an inshore lizardfish (Synodus foetens) showed up in my net (please see photo).  I’ve had only limited success with them in captivity and so released this one after taking some photos.

Shore Crabs in the Aquarium

As is my way, I tried my hand at keeping Asian shore crabs in captivity, and was pleasantly surprised.  Although in nature foraging is tied to the tidal cycle, captives abandon this strategy and soon appear at all hours (in contrast, native fiddler crabs that I have kept became active according to an internal clock – feeding and retiring in groups, despite the absence of a tidal influence).  Shore crabs feed ravenously on any and all plant or animal based fish foods.

I set up a group in a large estuary exhibit at the Brooklyn Children’s Museum, and they have done quite well there.  The crabs forage underwater and on rocks protruding above the surface, and co-exist with sand shrimp, striped killifish and other natives (in a small aquarium, they should be monitored closely for aggression).

Crab Alternatives

Please check out our extensive selection of frozen and freeze-dried  fish foods.  Many contain whole marine animals, and are an excellent addition to the diets of aquarium fishes and invertebrates.

Further Reading

Information about this and other introduced marine animals and plants is posted at http://www.seagrant.uconn.edu/INVID.HTM.

Please write in with your questions and comments. Thanks, until next time, Frank Indiviglio.

Koi: To Feed or Not to Feed and A Matter of Extremes in the Spring

Anyone who keeps a koi pond in cooler temperatures has been there. You start getting a few warmer days in late March and your koi, who had been inactive all winter, begin to swim around and look for food. Being the “good” koi keeper you are, and just an all around nice person, you start feeding your hungry friends almost immediately. The feeding continues to increase, while your pond continues to get greener. Meanwhile the local garden store is getting in a load of excellent looking Asagi or Shiro Utsuri Koi direct from Japan next week, and though you already have a questionable number of little Koi in your 1000 gallon pond, one more couldn’t hurt, right?

Pond keepers are creatures of extremes and it’s nothing we’re ready to apologize for (I mean, koi are soooo cool!). But, from a biological balance perspective, it’s really easy to start tipping the scale in your pond in favor of algae and unfavorable health conditions, particularly in the cooler weather.  

Believe it or not, koi in an outdoor pond do not have to be fed to survive. Being the scavengers that they are, they’ll have no trouble finding the nutrients they need among the detritus, bugs, and general wild things that end up in your pond throughout the season. What this means to you is everything you add to the pond, whether it be more fish, fish food or plants, adds to the nutrient load. In early spring, this nutrient load is particularly important for several reasons. First, your beneficial bacteria are not yet running full steam. This means ammonia takes that much longer to break down. When you combine that with the fact that your fish, and their immune systems, are still in slow motion due to the cooler water temperatures, a high nutrient load can cause problems. In addition, the natural “nutrient sucker-uppers,” your aquatic plants, are also struggling to gain a hold for the new season, so that part of your natural filtration is crippled as well.

Many koi keepers than ask, how can I get around this problem? I love my pond and I’m not going to stop feeding my koi, and I’ll probably add more fish to the nutrient load from time to time because they’re too awesome to pass up. Our response to you: avoid the extremes. Be sure to have the necessary test kits on hand to make sure levels remain nominal throughout the season. If you start to see problems, just like in an aquarium, try a water change, or add some bottled bacteria to help the chemistry settle. If your pond starts to get cloudy or full of algae, try adding more plants, or cutting back a few feedings. If you’ve tried all of these solutions and the problems are not going away, it may be time to consider a larger filter system or (gasp!) trimming your koi stock a little.

Good luck with your pond this season!