“An old pond
A frog jumps in
The sound of water”
Basho, “Matsuo”, c.1689
Exciting underwater exploration this time, with miniature dragons and fish in armour, as we look at fish and amphibians in Spring. Picture 9 contrives to show a pond scene with three fish species (three- and nine-spined sticklebacks and a minnow), some great crested newts and the spawn of frogs and toads. As an aquatic biologist, I am happy to be able to talk about fish and amphibians as part of this series of posts.
As a child in the 1970’s, I was an avid fisher (and then liberator) of both three-spined sticklebacks and minnows. In both cases, they were captured with a home-made funnel trap which my Dad showed me how to make out of an old wine bottle. We took a bottle with a concave base, filled it with dry sand and then gently knocked out the round base of the concavity by tapping gently with a nail and hammer until it came out. Empty out the sand, tie on a string, add some bait - it was ALWAYS white bread – and fill with water and with the bottle top still screwed on or the bottle corked), place in the river or burn with the new funnel entrance opening facing downstream, tie the string to a big stone or a branch and just wait for half an hour to an hour. It nearly always ended up with lots of fish in it. I realise now that the white bread, while it probably wasn’t very good bait for these species, made it easy to see from the bankside when there were fish in the bottle, as they swirled it around.
The minnow (Latin name: Phoxinus phoxinus), the uppermost of the three fish pictured, is a small member of the carp family, the Cyprinids, and is very widespread in freshwaters across most of Europe and Asia, as it says in Peter Maitland and Niall Campbell’s book, “Freshwater Fishes”: “from the Atlantic coast of Ireland to the Pacific coast of China.” In the British Isles, it is absent only from the Western Isles, Orkney and Shetland. Minnows live in a wide range of waters, from small, fast upland burns and streams, to lochs, reservoirs and large rivers in the lowlands and often form huge shoals in the shallows (my childhood memory is of (relatively) massive shoals in the Whiteadder, a river in the Scottish Borders, where I used to go bottle-trapping for them). According to Professor Maitland in “Scotland’s Freshwater Fish. Ecology, Conservation and Folklore”, it is perfectly likely that minnows arrived in Scotland without human intervention, although there is no doubt that they have also been moved around extensively by anglers, principally through their use as live bait. It is likely that the minnow’s distribution in Scotland has increased since the Spring book was published in the period 1959-61, as it continues to expand its range in northern Scotland. Professor Maitland concludes that, while the minnow receives no special protection in Scotland, it is in no need of any as it is a widespread and successful species. I can only concur with his thought that, “Like other small fish, it deserves to be spared from the despicable practice of livebaiting.”
There are two stickleback species featured here, the three-spined (the middle fish) and the nine-spined (the lower one). There is another species found in Britain, the 15-spined, but that is wholly a sea fish. Both species in this picture share the ability to live in waters spanning the range from freshwaters to the brackish waters of estuaries and, in the case of the three-spined stickleback, in full-strength seawater. The name stickleback refers, of course, to the spines that have formed from modified fin rays, with, on the three-spined species, spines to the side and on the underside too. Also, it seems that the more that it lives in saline conditions, the greater the three-spined stickleback develops armoured bony plates around the outside of its body. Apparently the spines and armour plating don’t offer as much protection against being eaten as was originally thought so, perhaps the spines are more important for courtship displays, or signalling in the sizeable shoals in which these fish are often found.
The nine-spined stickleback (Latin name: Pungitius pungitius, which can actually have between 8 and 12 spines), although native to Scotland, is the less widely distributed of the two species. My excellent source for fish, Professor Maitland, reports that it has suffered a substantial decline over the last century, "disappearing from many of its former sites because of pollution and loss of habitat”. The three-spined stickleback (Latin name: Gasterosteus aculeatus) is one of the original fish species that colonised the post-ice Age Britain and in contrast to the nine-spined species is probably, other than for eels and brown trout, the most widely distributed fish species in the country. It is probably also the most studied fish species in zoological and evolutionary science, being easy to keep and breed in laboratories, and exhibiting many fascinating behavioural traits that have contributed much to animal behaviour science and evolutionary theory. The breeding behaviour of this species is particularly interesting, with the male aggressively holding a territory in which he builds a nest, attracting in a female with his special zigzagging dance, to lay her eggs, which he then fertilises. The female fish then leaves, playing no further part. The male guards the eggs until they hatch, then shepherds the young fish, gathering them in his mouth and spitting them back into the nest when they stray! Professor Maitland, in “Scotland’s Freshwater Fish. Ecology, Conservation and Folklore”, suggests that, other than for some rare spineless populations, the three-spined stickleback requires no special protection in Scotland as it is doing very well at present (and, so I surmise, it probably hasn’t declined since the Ladybird Spring book was published!). I could write about this wonderful little fish all day – but I’d better not...
Finally, to the amphibians – the newts and the spawn and its producers, common frogs (the big floating clump of spawn) and toads (the strings of spawn). This is the only picture in the whole series of four books where amphibians are a key element. A significant change has taken place in the status of amphibians since these four Ladybird books were first published (although not necessarily yet to the same extent in the UK). There is concern world-wide about a major decline in amphibian populations. See here and here for examples of this concern reflected in media coverage. A range of pressures – habitat destruction, disease, non-native invasive species and, perhaps increasingly, the effects of a changing climate, are all thought to be contributing to this decline. In the UK, it is difficult to find long-term information on trends for amphibians. There hasn’t been the same degree of rigorous survey and monitoring at national level for as long as there has been for, say, birds. I plan to talk about threats and conservation of ponds as habitats later in this series, when they are pictured again but, for now, it is enough to note that, according to Pond Conservation, the non-governmental organisation promoting the conservation and creation of ponds in the UK: “the common frog the facts are:
- from 2007 to 2009, surveyors taking part in the National Amphibian and Reptile Recording Scheme saw frogs in just over half of the ponds in the countryside.
- in 2009 Pond Conservation’s surveys of garden ponds suggested that Common Frogs are seen in practically all garden ponds and breed in around two-thirds of them.
There probably are fewer frogs than in the past but, at least for the time being, the Common Frog is still a common animal – there are probably millions of them.”
Scottish Natural Heritage has produced a good introductory guide to amphibians (and reptiles) in Scotland, which contains some great pictures. It suggests that: “The Common frog is widespread and is found in suitable locations throughout Scotland, except in the most well drained places. It also occurs on some of the islands of the Inner Hebrides and has been introduced to Shetland”. For the Common Toad, SNH says: “The species is widespread in Scotland but the more specific habitat requirements make it generally less common than the frog.” I have both species, as well as palmate newts, in my garden, although I only ever see the frogs and newts regularly in the garden and pond – I have no idea where the toads are most of the time.
The Great Crested Newt (Latin name: Triturus cristatus) is the mini-dragon of Britain’s amphibians, and a poster boy for the conservation movement in Britain. Scottish Natural Heritage (SNH) says of this species: “The Great crested newt is an impressive amphibian. It may grow to 16 centimetres long ... The skin has very fine warts, which is why it is also known as the Warty newt. In the breeding season, the male develops a jagged crest along the body to the base of the tail, and has a silvery stripe along the sides of the tail. The tail also develops a crest and the underside enlarges. The belly of both sexes is strikingly marked by irregular black blotches on a bright orange background.”
It is a truly striking beast in breeding colours. Courtship involves a waggling dance in mid-water, which you can see on the video here. SNH says: “The Great crested newt is rare in Scotland and about 100 breeding ponds are known, although new ones are frequently being discovered. Strongholds for this species are Dumfries and Galloway and the Central belt. There is also a cluster of populations in the Inverness area.” Due to previous losses of populations from, for example, development, pollution, dumping in or drainage of habitats, this species now has strict legal protection in Britain, and there are lots of local conservation projects aimed at creating new pond habitats close to existing populations.