THREE-SPINED STICKLEBACK AND NEST.
Here we are at the pond, how clear it is, and how beautifully green are the few patches of star-wort in the water! As the grass is quite dry we can all sit down so as to get our eyes as near to the water as possible; never mind a few crawling ants, May; if they bite you, I shall not feel it. Ah! do you see that little fellow with crimson breast and eyes like emeralds? He sees us, for look how disturbed he seems; now he darts away and hides under a weed, but soon returns to the same spot; it is pretty certain he has a nest close by. I will put my walking-stick into the water near him. Well, actually, the brave little fellow is not the least frightened; see, he bunts his nose against the stick, and is very angry; he is afraid of some danger to his nest—this makes him so bold. Now I have made out where the nest is, it is close under him; do you see a few small holes in the mud at the bottom of the water? No, you don't see anything; well, then, give me my stick and I will point them out. There now, do you see what I mean? Yes, you do; that is all right. "Let us get the nest out of the water," said Jack. Have patience; let us watch what the fish is doing; see, he is busy fanning away with his tiny fins directly over the nest. "What is he doing that for?" said Willy. The quick movements of his fins bring fresh currents of water to the eggs or little fry that may be within. Ah! did you see that? another fish came near the nest; how furiously our brave "soldier" charged him; how quickly the intruder retired! I do not think he will dare to approach so near again for a long time, for those sharp spines on the under side of the soldier are like a couple of bayonets and can inflict serious wounds. Let us leave this nest for a time and try to find some more. Now that you have once seen a nest, you will not have much difficulty in finding others. Willy soon found another nest; "just look," he said, "there are a lot of the tiniest little things close to the nest." Yes, indeed, so there are; the eggs have hatched, and these are the little fry; there is Father Stickles quite proud of his numerous family, and quite ready to fight for them should any enemy be rash enough to intrude, for you must know that sticklebacks, like many other fish, do not object to eat the young fry of their neighbours, and if the parent there—it is the male only that is the protector—were to be removed, a hungry pack of other sticklebacks would crowd around and make sad havoc amongst that happy little family. I remember some years ago having once taken a father stickleback away from his nest, and, after putting him in my collecting bottle, I sat down to watch the result. Soon an invading army of other sticklebacks approached and attacked the nest for the purpose of getting at the clusters of eggs it contained. They pulled it about sadly, till I began to be sorry for what I had done. I returned the captive-parent to the water; at first he hardly knew where he was, and seemed confused, the result, no doubt, of his confinement in the bottle; but he was not long in coming to himself—he remembered his nest and the treasures it contained; he saw that devastating army all around it, and, summoning all his courage, the soldier-parent began an attack, now rushing at one and now at another enemy, till he was left alone on the battle-field, having thus gained, single-handed, a glorious victory indeed.
Well, we will take this one home, with nest and eggs it contains. You see the nest is a mass of tangled grass roots and other weeds; now that it is out of the water it is a shapeless mass. However, here is a cluster of pinkish eggs, and if you look closely you will see two little specks in each egg; so that the fish is being formed, for these are the little thing's eyes. You can see, too, the tiny things jerking their tails about every now and then. It is most interesting to watch the care the parent takes of his little ones when hatched. Some few years ago I put a male stickleback in a basin of water in charge of his nest. When the young ones were hatched it was most curious to notice his anxiety for their welfare. Of course young sticklebacks, like young children, are of an inquisitive turn of mind, and apt to play truant too occasionally; but should some little fellow wander too far from the nest, Father Stickles hurries after him, takes the little truant in his mouth, and spits him out right over the nest. This I repeatedly witnessed myself, and I have no doubt you will be able to see the same thing yourselves.
"Are not sticklebacks quarrelsome little fish?" asked Willy. Yes, they are very fond of fighting, and they are so bold that they do not fear any enemy, whatever his size. I once kept a small pike, about ten inches long, in an aquarium, into which I also introduced five or six sticklebacks. I suppose the pike did not much like the look of the prickles or spines, for he did not eat the fish. Once I saw him make the attempt, but after getting Master Stickles into his mouth, he quickly threw him out again, not relishing, I suppose, the sauce piquante of the spines. The sticklebacks were really masters; they tormented Mr. Pike dreadfully; first one would take a bite at his tail, and then another, till the tail had a woful expression indeed; so I turned the pike into a pool of water, and I dare say the retail business has long ere this been completed.
"Are there any other kinds of fish," asked Willy, "that make nests and take care of their young ones like the three species of sticklebacks?" Yes, there are several kinds of fish which do so, but no other British fresh-water kinds, I believe. There is the salt-water Lumpsucker, a fish of strange form and brilliant colour—you know the pickled specimen in my study—whose young soon after birth fix themselves to the sides and on the back of their male parent, who sails, thus loaded, away to deeper and more safe retreats. There are the long pipe-fishes, the males of which possess each a singular pouch on the tail; in this the eggs of the female are deposited and matured; the young ones occasionally leave their strange abode, and after swimming about for a time return to it again, reminding us in this respect of the kangaroos and opossums amongst mammalia. There are also fish which inhabit the rivers of Demerara which make nests and show great attachment to their young ones, and I dare say several other fish will be found to do the same.
SNAIL LEECH.
"Oh! papa, do look here; as I was turning over this bit of flat tile I saw in the water I found a creature something like a leech, and on raising it up I saw what looks like a quantity of the animal's eggs, and she seems to be sitting upon them as a hen upon her eggs." All right, Jack; let me look, I dare say it is one of the snail-leeches. Yes, to be sure it is, and here are the eggs which the creature carefully covers with her body, and upon which she will sit till the young ones are formed; the small brood, sometimes one hundred and fifty or more in number, then attach themselves to the under surface of the parent, and are carried about wherever she goes. There are various species of this interesting family; all are inhabitants of fresh water; some incubate or sit upon their eggs, others carry them about in a hollow formed by the contraction of the sides. They have a long tubular proboscis, by means of which they suck out the juices of pond-snails and other water creatures. These snail-leeches move along in the same way as the common horse-leech and the medicinal leech, namely, by fixing the head-part on to the surface of some substance in the water and then drawing the hinder part up to it; they then extend the head-portion and fix it upon another spot, again drawing up the other extremity. But the leeches, properly so called, have all red blood; that of the snail-leeches is colourless.
"Is the leech used to bleed people when they are ill ever found in the ponds of this country?" asked Willy. I believe it is rarely met with now-a-days; most of the leeches used in medicine are imported from Spain, Hungary, the south of France, and Algeria; many millions are brought every year to this country. The medicinal leech, was, however, once pretty common in the lakes and pools of the north of England. The poet Wordsworth introduces us to an old leech-gatherer lamenting the scarcity of the animals in the following lines:
"He with a smile did then his words repeat
And said that gathering leeches far and wide
He travelled; stirring thus about his feet
The waters of the pool where they abide.
Once I could meet with them on every side;
But they have dwindled long by slow decay;
Yet still I persevere and find them where I may."