Captive husbandry of Emydura species
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The
Emydura species is kept by breeders all around the world. The most
commonly kept are Emydura subglobosa subglobosa and Emydura
macquarii macquarii. Emydura subglobosa subglobosa is the
only Emydura with its natural habitat being out of Australia. It
inhabits the rivers of Irian Jaya and Papua New Guinea. This is one of the
factors why this particular species is available in pet stores and markets
across the world. Of course, the bright red, orange and pink colours add
a lot of attractiveness to this species which even increases the demand
for it. Emydura macquarii macquarii is also readily available (slightly
less than E. subglobosa subglobosa) because its natural habitat
is the biggest one out of all Emydura species’ habitats.
Outside of Australia, there is a lot of these turtles, but the majority
of them is captive born. All other Emydura species are not common in captivity
(unless you live in Australia and own a permit). Therefore this paper especially
addresses the former two Emydura species. The turtles kept under
scientifically wrong names, such Emydura signata or Emydura
krefftii, are one of the four currently recognized subspecies of Emydura
macquarii. For more information see the Emydura Taxonomy.
Both Emydura subglobosa subglobosa and Emydura macquarii macquarii
are relatively hardy. If you are an experienced turtle keeper and know a
bit about this particular species requirements, you should do fine. Be aware,
the information below is mainly based on my personal experience and may
vary from other sources to some extend.
The Emydura species require a relatively large aquarium or a pond because it is an excellent and fast swimmer. If you can provide your animals with an outdoor setup and your climate allows it, try to keep the species outdoors where they get some direct sun and have plenty of room to move around. If for some reason you have no other choice than keep your animals in a tank, make it big. The smallest size of a tank that I would advice to keep an adult pair of E. subglobosa subglobosa in would be 120 cm / 60 cm / 40 cm [L/W/H]. I recommend using even a bigger tank for Emydura macquarii as it reaches of bigger sizes than E. subglobosa subglobosa. The tank should have a fixed platform that serves two basic purposes. Firstly, females need an area where they can dig a nest in which they lay eggs. Secondly, the species (especially Emydura macquarii) get out of water to sunbathe(1).
(1) The
Emydura species have been observed to sunbathe, but this behaviour
is not uniformly common for all specimens. My Emydura subglobosa subglobosa
specimens do not climb out of water in order to sunbathe. I primarily relate
this to the water temperature they are kept in. As I keep my E. subglobosa
subglobosa with some Carettochelys insculpta specimens, the
water temperature is from 28°C to 30°C. This temperature is more
than sufficient for the turtles’ bodies to maintain appropriate body
temperature. The light, which is required to acquire vitamin D3 that is
needed for utilizing Calcium, can be absorbed by turtles without them having
to get out of water. I have observed E. subglobosa subglobosa with their
rear legs stretched out to lean against either floating water plants or
a shallow bottom of the tank – a behaviour which I consider as a form
of sunbathing.
Clean water in your tank is one of the main criteria for the Emydura species to thrive and stay in good shape. If a constant in-out-flow cannot be maintained, use a powerful filter(2) and change the water as frequently on a regular basis. The water quality for the Emydura species should be more or less the same as for the Carettochelys species, so view the Water Quality for detailed information. Emydura species optimal water temperature ranges from 23°C to 29°C. The species becomes lethargic at water temperatures of 15°C to 17°C but nevertheless still attempts to escape from a diver. Emydura species in Macleay drainage, NSW is slow but active throughout the winter temperatures of 4°C to 8°C (Legler, 1993).
The recommended water temperatures:
Emydura
subglobosa subglobosa 27-29°C Emydura
subglobosa worrelli 26-28°C Emydura
victoriae 26-28°C Emydura
tanybaraga 26-28°C Emydura
macquarii macquarii 23-26°C Emydura
macquarii krefftii 25-27°C Emydura
macquarii emmotti 24-26°C Emydura
macquarii nigra 25-27°C
If you notice there is something with your water that does not look right, the best advice is to change it as soon as possible.
(2) The usage of a powerful filter does not exclude regular water changes
no matter what filer media is used.
If a constant in-out-flow cannot be maintained, a powerful filtration system is a must. Of course the best way of keeping the water clean is to change it as frequently as possible, but this activity can get really time consuming and expensive. A good filtration system does not substitute regular water changes, but at least it expands the intervals between them. No matter whether you decide to use an up-flow or a down-flow filter system, what really counts is the size of the main chamber and the medium used for filtration. The filters which are readily available in pet shops are no good for turtle setups(3) and with a bit of knowledge you can build an effective filter system on your own(4). Basically all you need is a water pump, some kind of chamber (for example a used barrel), a few rubber or plastic pipes and some kind of effective filter medium. As for the choice of the most appropriate and effective medium, there is no medium which could be singled out as a winner as a proof of which there are on going debates among both scientists and public on the pros and cons of various media. It is not an objective of this project to touch these debates in any way, so let's just list most frequently used filter media: carbon, ceramic rings, synthetic wool, sponge, peat, etc.
(3) These filters are mainly designed for fish setups. They have small
chambers (which can take up only a limited amount of the filter media) thus
the expected effect is reduced. Remember that defecating of turtles species
is much greater then that of fish.
(4) On the Internet, there are numerous manuals and tips on how to build
a pond/tank filter on your own.
Appliances and additional material
If you want your captive Emydura specimens thrive, you will need a set of appliances which are used in order to imitate the natural conditions as much as possible. Here is a list of appliances(5).
- Tank [see the Tank section]
- Small plastic/glass tank - This serves two purposes. First, it can be
used as a temporary place or your turtles while you are cleaning the big
tank. Secondly, it can be used for your newly acquired specimens that should
undergo a quarantine period during which they should be placed separately
from your other specimens. The size of the quarantine tank should be chosen
according to the number of specimens (and their size) you are planning to
keep in it.
- Filter System [see
the Filter system section]
- Water Heater - The water temperature should be maintained between 23°C
and 29°C, depending on the Emydura species you keep in your
tank [see the Water section for water temperatures required by particular species]. For details
on temperature please see the Water section. The rule of thumb says the
night temperature can drop 2-4 degrees below the daily temperatures. If
possible, try to keep the heater out of turtles' way, especially the electric
wire should be somehow hidden so that turtles do not have access to it.
- Thermometer - To monitor the temperature in your tank, you need a thermometer.
There are too types, one being internal, which is attached to a tank wall
by a pair of suckers, and one external one, which can be applied to tank
wall from the outside as a sticker. I prefer the latter one as it is not
an extra obstacle in the tank and it is accurate enough.
- Light system – Emydura species need either day light (applies
for outdoor setups) or a full-spectrum light (applies for indoor setups).
When I write 'Full Spectrum', I mean all the wavelengths, so do not get
cheated for there are many products who's manufacturers claim they produce
full spectrum light while they do not. The light is required in order to
acquire vitamin D3 that is needed for utilizing Calcium, an essential mineral
for the skeleton, carapace and plastron.
- Incubator - You can either buy one or make one yourself.
- Sand - Pre washed river sand can be used as a bottom layer in your tank
setup. It also is used as a nest medium(6).
(5) We avoid mentioning any particular brand as this project is purely
scientific and serves no commercial purposes.
(6) Sand is not the only material a turtle female can lay eggs in. Many
breeders advice to use coarse vermiculite instead.
There is a special section dedicated to this topic; just follow this link.
As long as they are kept in clean water, get enough of full-spectrum light and are fed proper foods, the Emydura species are relatively hardy.
This section is still under construction. It is going to be discussed in detail in the Breeding section.
With the information above, you should provide your Emydura specimens with proper care - under which they should thrive. If you have any comments or questions regarding the captive husbandry of the Emydura species, please contact us. We will be more than happy to assist you. Watch out for updates of this care-sheet because it is meant to be a live document and new stuff will be added as you ask new questions which are not already answered in the paragraphs above.