The creatures in and near the pond
In addition to the fish we add intentionally, animals we didn’t put in settle in all ponds sooner or later. We generally don’t mind, as it brings life into the pond and makes it much more interesting. There are only a few animals we really don’t like: parasites, such as fish leeches, predatory dragonfly larvae (which can be dangerous for fry) and a few more.
Aquatic plants can also be „introduced” into your pond by water birds. So don’t be surprised if you find things you never planted growing in your pond!
Water birds, wind, rain and even animals drinking from your pond can introduce animals too. Snail eggs and plankton, as an example, can migrate when you add aquatic plants. Fish are even happy to eat the water striders (Gerris lacustris) you see on the water surface, which can be up to 3 cm long. These water striders can travel far on land to “access” your pond.
The most common dragonfly species are the southern hawker (Aeshna cyanea) and the broad-bodied chaser (Libellula depressa). Dragonflies don’t sting and they enrich our pond life. They prey on other insects, e.g. mosquitoes, in the air. But their larvae are highly predatory and catch EVERYTHING they can fit in their strong jaws. This includes small fish, newts and young frogs.
Water boatmen, great diving beetles and dragonfly larvae can also be dangerous for fry. However there is nothing you can do. You just have to accept that these predators may enter your pond. The only solution is to try catching these villains by hand.
Frogs and toads like to use your pond as a retreat and for reproduction. The grass frog (Rana temporaria), the edible frog (Pelophylax esculentus) and the common toad (Bufo bufo) are the most common species there. All anurans feed on insects and worms. The male animals of various species croak at different volumes. Green frogs can croak so noisily that they disturb your neighbours. Luckily your neighbours can’t take legal action against “your” frogs. Anurans sometimes hibernate in the mud of your pond. Then it’s better when the water surface is not completely frozen over. Here an ice preventer with aeration ( JBL PondOxi-Zestaw ) can help. Newts, like the smooth newt (Lissotriton vulgaris), live in the water from March to August. The eat anything they can fit in their mouth.
Mosquitoes lay their eggs in the pond (and in any other patch of water). Fish living in the pond regard mosquito larvae as a delicacy which helps keep their numbers down. Ponds without fish stock definitely have a lot more mosquitoes!
Did you know that the JBL remedy JBL ArguPond Plus helps combat mosquito larvae? This could be a solution for anyone who has a pond with no mosquito larvae eating fish.
Pond mussels which are often offered on the market are live mini-filters. But please don’t expect a few pond mussels to replace the pond filter!
In order to reproduce, bitterlings need pond mussels to spawn inside.
You can find all sorts of water snails in your pond: big-ear radix, great ramshorn, pond snails and great pond snails. Their gelatinous clutches are mostly introduced by water plants. All native snail species are harmless and feed on algae.
You are welcome to add your turtle to your pond in summer, assuming the turtle can’t just escape and migrate to natural waters. This would lead to a disturbance of fauna and possibly jeopardise the native pond terrapin.
The least welcome visitor to your pond is the grey heron! It is beautiful to look at but is a real danger for your fish! If you notice wounds on the fish’s back, this may be caused by the grey heron. There are quite a few remedies for them, but only a few really work. The plastic heron is quite comical as a solution. The heron thinks: I’ll go and see what my pal is up to and keep it company. Deterrent effect: zero! An electric fence might work well, but it looks unsightly. Sprinklers, triggered by light barriers, also work, but they need to be repositioned now and then because herons are fast learners.