04 - Within the Deep by R. Cadwallader Smith - Some Strange Nurseries

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Episode Transcript

Speaker 1 (00:01):
Lesson for of Within the Deep by R. Cadwalader Smith.
This LibriVox recording is in the public domain. Lesson for
some strange nurseries. As a rule, nests or nurseries are
unknown in the world of fishes. They lay their eggs
and leave them, and the young ones have to fight

(00:22):
their own battles in a sea full of fierce and
hungry enemies. Indeed, it often happens that a parent fish
is eager to make a meal of its own children.
The codfish lays about nine million eggs. You would hardly
expect the female codfish to make a nursery for such
a family. She would be much worse off than the

(00:42):
old woman who lived in a shoe. As a matter
of fact, the eggs are laid in the open sea,
and the cod shows no interest in them, but leaves
them to become food for many a roving enemy. Those
cousins of the shark, the skate, and the dogfish are
more careful of their eggs. Have you ever found their

(01:03):
empty eggs on the seashore? Children call them mermaids purses,
but they are more like little horny pillow cases than purses.
When first laid, the dogfish's egg has a very long
string or tendril at each corner. As the fish lays
the egg, she winds these tendrils round and round a

(01:23):
sea plant. Thus the egg is fixed firmly until the
young one is ready to escape from within. The skate's
egg is much the same, only there is no tendril,
but a curved hook at each corner. These hooks, of course,
serve as anchors to hold the egg, no doubt they
catch in weeds and stones. One fish you see ties

(01:45):
her eggs with strings, the other uses anchors. These large
purse eggs are like cradles, and the baby's skates do
not slip out of them until they are quite ready
to look after themselves. In the ocean, there are fish
in the sea which take great pains to save their
eggs and babies from harm. They will even defend them

(02:06):
at the risk of their own lives. Of course, these
careful parents do not have huge families like the cod. No,
the fish that care for their young have small families,
but the babies have a much better chance of living
than the baby cod. It is one of nature's wise laws.
Our common stickleback tiddler or red throat as boys call

(02:29):
them builds a nest in ponds. He has a seaside cousin,
the fifteen spined stickleback, who is also a nest builder.
This little fish is fairly common round our coasts, living
in weedy pools by the shore, where it devours any
small creature unlucky enough to come near. It is about

(02:50):
six inches long. This sea stickleback with a long snout,
and its body is very thin near the tail. To
build his nest, this little fish chooses a quiet corner,
then gathers pieces of green and purple seaweed. He takes
the pieces in his mouth, pushing them about until the
shape is to his liking. Having got his nursery to

(03:12):
the right size and shape, the little builder next fastens
it together. How can he do this? What mortar can
he find in the sea? It is quite simple. He
uses threads, which come from his own body. He swims
round the nest again and again, and each time a
thread is spun, binding the clump of wheat into a safe,

(03:33):
tight nest for the eggs. When the task is done,
there is a weed nursery about the size of your fist.
Now all is ready for the eggs to be laid
by the female stickleback. You would expect them to be
kept in a hole amid the nest, would you not.
Instead of that, they are tucked a few here, a
few there in the weed. Then the father stickleback mounts guard.

(03:59):
Woe betid any small fish looking for a dinner of
stickleback eggs. The gallant little sentry will rush at him
with spines as stiff as fixed bayonets, ready to do
battle to the death. When the young are hatched out,
he still keeps guard. They are not allowed out of
the nursery for some time. The watchful parent forces them

(04:20):
back if they try to wander out into the perils
of the shore pool. Let us look at another nest builder,
the sand goby or spotted goby. He is common enough
in the pools at low tide, but not easy to find.
You can look at him yet not see him, for
he takes the same color as the rocks and sands

(04:41):
of his home. Amid the glinting lights and shadows of
his rock pool. With the background of sand, rock and weed,
this little fish is nearly invisible. Of course, it is
a dodge, and a useful one to escape the eye
of the enemy. Perhaps you will not think the spot
uded goby so clever at nest building as the stickleback.

(05:04):
He likes to use a ready made house, whereas the
stickleback finds his own bricks and mortar. In the pools
off the shore. There is no lack of houses to
let the empty homes of shell fish are there in plenty.
So the little goby, when nesting time comes, hunts round
for the empty shell of a cockle, lying with its

(05:24):
hollow side to the sand. This shell is to be
used as the roof for the nursery. The goby's next
task is to make a hole beneath the shell. He
sets to work, and, by scooping out the sand, makes
a hole about as large as a marble. To keep
the sand from tumbling in, he smears the hole with slime,
which soon binds hard like mortar. Now the nursery is

(05:48):
nearly ready, but a passageway is made passing under the
edge of the shell, and then, to make things quite safe,
the whole roof is covered with sand. It then looks
more like a bump in the sand than a fish nursery.
The female goby enters the nest and leaves her eggs
in it, and then the little father fish is left
in charge. He rests on the sand near the entrance.

(06:12):
When the little ones appear, he seems to think he
has done his duty, so away he swims, not staying
like the father stickleback to guard the youngsters. Again we
see that the father, and not the mother, is the
builder and nurse. That very strange creature, the pipefish, has
the most peculiar nursery of all. He uses no building material,

(06:37):
no made up nest of weed or sand for him. No,
he prefers to carry his eggs in his pocket. To
be more exact, there is a small pouch under his body,
and there the eggs are kept until they hatch. Meanwhile,
the pipe fish goes about his affairs in the pool
as if nothing particular had happened. You will see more

(06:58):
about this funny little fish when we come to our
lesson on the fish of our rock pools exercises One
what are the eggs of the skate and the dogfish like? Two?
How does the sea stickleback build his nest? Three? Where
would you find the sand goby, the pipefish and the

(07:21):
sea stickleback? Four? How does the sand goby build its nest?
End of less than four