The Latest Buzz: Freshwater Bee Shrimp (Full Article)Author: Amanda Wenger
Freshwater dwarf shrimp of the order Atyidae have exploded onto the hobby scene in recent years. Starting in the early 2000s with the global introduction of the red cherry shrimp (Neocaridina heteropoda var. “red”), breeders and importers all over the world have been bringing new and exciting species and color morphs to the market, with new strains now appearing on a near-monthly basis.
Of the many available species of shrimp, the bee shrimp (Caridina cf. cantonensis) is currently one of the most diversified, with over a dozen variants on the market today. The widespread popularity of this particular species is somewhat peculiar in that it thrives in a far narrower range of conditions than its more adaptable cousins in the genus Neocaridina (including the aforementioned red cherry shrimp).
Bees are not shrimp for the beginning invert keeper. New hobbyists who have done their research often start with commonly available Neocaridina species or Amano shrimp (Caridina japonica) and move on to bee shrimp only after they’ve had success in keeping the easier species. Apart from being less forgiving, bee shrimp generally carry a heftier price tag, which is reason enough to have some experience before investing in them.
Shrimp in general require very clean water, as they’re far more sensitive to toxins than fish. The bioload in the tank should accordingly be kept low, which is not as difficult as it may sound, since shrimp have a low impact on bioload. Only the smallest of fish, such as Otocinclus spp. catfish or least killifish (Heterandria formosa), are suitable as tankmates. For breeding purposes, however, shrimp should be kept in species tanks.
Since they are typically prey animals, shrimp like to have readily available hiding places. The addition of live plants provides shelter and helps remove ammonia from the water. Low-light aquatic mosses, such as Java moss, are wonderful additions to shrimp tanks. Another source of shelter the shrimp enjoy is cholla wood, the dried-out husks of the cholla cactus (often sold in pet stores for use with hermit crabs).
There is a general consensus among shrimp breeders that bee shrimp need cooler waters that do not exceed approximately 74°F. This is more or less true. Bee shrimp do thrive in cooler temperatures, but their failure to thrive in warmer environments most likely has just as much to do with oxygen saturation as the heat itself. Oxygen dissolves much better in cool water, and bee shrimp need well-oxygenated water. Keeping them in temperatures above 76˚ will require the addition of an extra airstone or air-operated filter. Even so, it’s not a good idea to keep them in temperatures above 78˚. As such, a heater is unnecessary in all but the coldest environments. I’ve had plenty of success with these shrimp in temperatures as low as 65˚F.
Temperature aside, bee shrimp also like their water soft and just slightly acidic, with a pH of 6.5 or so. Many breeders use reverse osmosis (RO) water to give the shrimp an ideal environment. However, pure RO water is deficient in minerals (particularly calcium) that are vital to shrimp exoskeletons. The addition of a mineral rock or a shrimp-specific GH booster will help replace the missing minerals without adding more than what is necessary. Another option is using a partial mix of RO and tap water. A GH of 4–6 with a carbonate hardness of approximately 2 is ideal.
Personally speaking, I use tap water combined with a pH-lowering substrate (such as the myriad of substrates designed for planted tanks) and a pinch of montmorillonite clay to provide calcium. Depending on your local parameters, this approach may or may not work for you.
The wild bee shrimp, native to China and Japan, has a rough pattern of broad, brown-black and white stripes on a clear body. A variant wild shrimp with a transparent body and thin dark bands, known as the tiger shrimp, also exists. All of the other strains of bee shrimp were derived from these two shrimp populations. Because these wild types are also the least inbred and fairly inexpensive, they make good first choices for a first-time keeper of bee shrimp.
Bring on the Colors
In the mid-1990s, a bee shrimp breeder in Japan by the name of Hisayasu Suzuki noticed that a handful of specimens in his wild-type population displayed slightly reddish coloration. Over the course of several years, selective breeding produced the first crystal red shrimp. Once these crystal red shrimp hit the market, other breeders refined the strain to improve the brightness of their color, delineation of their pattern, and overall coverage of the white stripes on the shrimp.
Today, a lettered grading system has been developed to describe the quality of the patterning on crystal red shrimp, ranging from C (the original red bee shrimp) to SSS (also known as mosura) grade. Oddly enough, despite being called a crystal red shrimp, the quality of the shrimp is determined by the amount of white it possesses, with the highest grades being almost entirely white. The grading system is also applied to the refined versions of the wild-type black coloration, known as crystal black shrimp.
A very recent addition to the hobby is the crystal white shrimp, which has thin, white stripes on a clear body. The most notable features of this shrimp are the eggs and ovaries of the females, which are an unusual minty, blue-green color. Crystal white shrimp have only started making their way to the United States in the past year or so. These new shrimp are not to be confused with the solid-white to yellow-white bee shrimp variety known as the golden bee, which has been around for several years now and a likely source of the increasing white coverage in higher-grade crystal red shrimp and crystal black shrimp.
The tiger shrimp, on the other hand, have mostly been bred to become darker. A strain with a blue body and orange eyes—appropriately called the orange-eyed blue tiger shrimp—was introduced to the hobby a few years ago. A combination of the dark blue body and increased coverage of the black stripes produced a near-black version of the shrimp, referred to as the black diamond or black tiger shrimp. Other breeders have focused on the coloration of the stripes, producing red-striped shrimp known (unsurprisingly) as red tigers.
Meanwhile, in Taiwan
In Taiwan, a group of highly selected strains of crystal bee shrimp, apparently all caused by the same mutation, have been introduced to the hobby in the past couple of years, carrying such creative names as red ruby, blue bolt, and black King Kong shrimp. Collectively, these variants are referred to as Taiwan bee shrimp, a reference to the location where breeders first developed the mutation.
Taiwan bee shrimp are the rarest and most fragile variants of the species. Being highly inbred, they are also prone to genetic defects and deformities and tend to be smaller than their wild-type counterparts. Because of the difficulties they present, they also command the highest price among bee shrimp, often in the hundreds of (US) dollars for high-quality specimens. Hopefully, with a few generations of outcrossing and stabilizing, these breeds will become less specialized and more readily available in coming years.
The other difficulty with bee shrimp, and shrimp in general, is keeping track of what variations can be kept together without hybridizing or muddling the genes of two different strains. The easiest solution to the problem is to just give each type of shrimp its own tank, but this, of course, is not feasible for most hobbyists, so who can be with whom?
Since the bee shrimp discussed are all the same species, Caridina cf. cantonensis, crossing strains does not technically result in a hybrid shrimp. However, it can undo all the careful selective breeding and produce a shrimp that is not nearly as attractive as either of its parents. Crystal variants, including the golden bee and Taiwan bee shrimp, can be kept together without fear of corrupting the appearance of future generations. The Taiwan gene is recessive to normal crystal appearance, whereas golden bee genes tend to merely increase the white coverage in the shrimp, a desirable trait. Tiger shrimp, however, cannot be kept with crystals—crossing crystal black shrimp and tigers will produce a kind of vaguely stripy, splotchy result known in slang as a tibee. Since the crystal white shrimp is so new to the hobby, it’s not yet clear what other, if any, bee shrimp it’s compatible with.
As a member of the genus Caridina, the bee shrimp can also be kept with a colony of a strain from the genus Neocaridina (for example, blue pearl or red cherry shrimp) and/or a member of the genus Paracaridina (which are less readily available to hobbyists).
Other members of the genus Caridina, such as the bumblebee shrimp (C. breviata) and C. hodgarti, should not be kept with bee shrimp to avoid hybridization. However, Caridina species that do not breed in fresh water, also known as low-order breeders, are acceptable tankmates. Examples of low-order shrimp include Amano shrimp and ninja shrimp (C. serratirostris).
Breeding bee shrimp is not much more difficult than keeping them alive and happy and, of course, having shrimp of both sexes. Females are more robust, having more convex underbellies and being slightly larger than males. In non-opaque varieties, they can also be determined by the presence of their saddle-shaped ovaries, located just behind the head of the shrimp.
Assuming both sexes of shrimp are present, when the female has just molted and is fertile, she produces pheromones that cause the male shrimp to swim in frenzied circuits around the tank, seeking her out. After their eggs are laid and fertilized, the females carefully stick them to their pleopods (swimmerets), located on the underside of the tail. A female with fertile eggs is referred to as “berried” due to the berry-like appearance of the egg clusters. The female proceeds to carry the eggs for the next month, diligently fanning her swimmerets to ensure a flow of oxygenated water, until they hatch.
On hatching, baby bee shrimp are miniature replicas of their parents and are left to fend for themselves. Since adult bee shrimp do not bother their babies, a species-only tank ensures a lack of predation on the shrimplets. Combined with clean water and ample food, a high survival rate is not difficult to achieve.
Where to Start
Should you decide to try keeping bee shrimp, start with the basics. Wild-type and early strains, such as low-grade crystal reds or crystal blacks, are the best choices. Start with a group of ten to a dozen and see how they do—once you’ve got a knack for keeping these shrimp happy, you can begin exploring the more costly strains if you so choose.
Since almost all dwarf shrimp find their way to the US from Asian exporters and are fairly new to the hobby, they are still far more readily available on the Pacific Coast than on the Atlantic. The most common bee shrimp to appear in local fish stores are the crystal reds. Procuring more exotic variants is still most easily accomplished through Internet retailers. You may also want to check with your local aquarium club to see if a freshwater invert breeder is in the area.
Bee shrimp are a diverse and fascinating group of invertebrates and well worth keeping if you’re up to the challenge. For hobbyists who want to move beyond the basics, these shrimp are a great place to look.
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