Discover Top Posts Tagged with #common bream

When I was a child, and nurturing my early fondness for natural history, I took an interest in European (or zoologically, Western Palaearctic) freshwater and sea fishes. I took an interest when I saw them in public aquariums, because they were different from the fish in tropical tanks. Because I didn't like to see animals injured, I never took up the sport of angling, which I reject as cruel, though I otherwise have mixed feelings about the sport, because anglers often respect fish and help to preserve their coasts and waterways. I say this because I am writing of a fish that are better known to freshwater anglers, than they are to the rest of the general public. However the fish in question, is an ecosystem engineer, and thus very important in habitats where it is indigenous.

Naturally fishes of such distributions are suited to garden ponds outdoors, but few native European species are traded regularly; orfe and tench are the only fishes of this nature that have ever been traded regularly, both in wild and domesticated color morphs, and their popularity lags behind those of goldfish and koi. I have never seen such a color strain of bronze bream, Abramis brama, though they too are British cyprinids. In a large aquarium, A. brama is an impressive animal and I wish to extol its virtues as an 'alternative' coldwater fish.

Bream commonly grow to lengths of between 25 centimeters or 10 inches long, up to 55 centimeters or 22 inches, but exceptional animals much longer than this length are certainly recorded. This species adjusts its growth when it lacks the opportunity to leave backwaters, by slowing its growth yet attaining reproductive age at smaller sizes, and continuing to consume more zooplankton as prey - an immature trait - relative to their similarly aged but larger conspecifics.

A. brama is native to a swathe of Europe, and has also been introduced into countries of Europe, that lay beyond its former, natural spread. Historically they were absent anywhere suth of the Alpine and Pyrenean mountain ranges, though they were and are present in the Black, Caspian, and Aral seas, and northwards into the Baltic region. The word 'bream' originally meant to sparkle or shine, and refered to the reflective qualities of the scales of some fish; in English the word has since come to be applied to any number of unrelated fishes with deep but narrow body shapes.

A. brama is sometimes referred to as the common bream, as well as the bronze bream; it actually is the fish reflexively associated with cognate names, in other Germanic countries such as the Netherlands and Denmark. The species is sometimes called the 'carp bream', thus pointing out a particular resemblance to the distantly related Cyprinus genus, but really, bream are themselves a kind of carp or barb. Sometimes they are called the 'freshwater bream' to distinguish them from coastal fishes popularly known as sea breams; however this is misleading due to other freshwater fishes also being known as breams, even within the same range as A. brama.

Bream are an omnivorous fish, and they are capable of switching between benthic foraging and midwater filter feeding when edible plankton are in abundance; the juvenile bream start off as planktivores, later switching to omnivorous benthivory. Their diets as adults include arthropods such as midge and caddisfly larvae, snails, bivalves, oligochaetes, and some plants, but more rarely other items - large bream may consume small fishes, which is not surprising given their size and the broad spectrum of their diet. In the aquarium, bream are not difficult to feed at all.

Bream are found in slow moving rivers, and also in natural lakes, and even man's reservoirs and canals. Although they are freshwater fish by nature, at least bream from certain populations can tolerate estuarine life. But in rivers, bream begin life in densely vegetated backwaters, before moving into the river channel as they age. Bream in rivers can be migratory, moving up and downriver by up to 10 kilometers a day, and they travel in large shoals. As a species, they associate with soft mud or sand bottoms in which they can forage easily, a preference which is something that ought to be replicated in aquarium environments, because such behavior is natural. Sediments are taken through their mouths and strained by gill structures, the ejecta then being spewed not through their mouths, but through their gill apertures.

Bream in the wild are known to switch their diets according to food availability, and throughout life they retain the ability to filter small arthropods from the water. The composition of bream diets leans towards the carnivorous, except for their feet which consume algae. However the exact proportions of the components of their diets, do vary by locality, reflecting the adaptability of A. brama to thrive in different environments, and alongside different competitors.

It is regularly observed that bream are able to tolerate life in brackish waters up to 13 ppt; experimentally, they appear to do well at water salinities up to 8 parts per thousand, whereas only adult fish tolerate a salinity up to 12 ppt. In such situations, the bream spawn in adjacent freshwaters, and the juveniles remain there before migrating downstream as they mature. Thus bream inhabiting brackish waters are actually anadromous, as are salmon, and cannot survive their whole life cycle in more than slightly brackish water.

In a similar vein, adult bream may survive in health where the pH of the water is as low as almost 5, but their reproduction is impaired in such acidic waters, and circumneutral values are more optimal for this species, adaptable though it certainly is. Bream are also recorded present in waters where the pH is above 9, yet these values too are outliers, and they are typically recorded where the pH is below 8.5. Such a broad tolerance makes bream suitable for the care of even novice aquarists.

Bream are well suited to life in an unheated aquarium, situated in a temperate living room with a temperature suitable for human comfort. In their wild habitats they may, in summer, experience higher temperatures than this, and they reportedly can survive water as high as 33 or 34 degrees centigrade, although this is obviously not a year round environmental condition in their range. Like koi and goldfish, they may be thought of as what they are; reasonably eurythermic freshwater fishes, optimised by natural selection so that they can well exploit warm summer temperatures as favorable.

Thus I think that the bream, like certain other Western Eurasian fishes and those from similar climates, should not remain so overlooked as it often is by fish fanciers. Although this species may grow large in our aquaria, they are far from the largest fish species to be encountered in our aquarium trade. And they do make an impressive sight, when aquarists are willing to provide them with living space in our homes. Should this fail, they do well in garden ponds and, as native fishes, they can appropriately be returned to the wild. No fish ought ever be euthanized because man makes a bad purchasing decision; in any case their flesh has a reputation as insipid.

#Abramis brama #common bream #bronze bream #European fishes #coldwater fishes #cyprinids