Rock pools are the great example of the small biological diversity. So we need to know about it and conserve it to save our environment and ecosystem.

1. ROCK POOL ECOSYSTEM
SUBMITTED TO : DR. R. SRINIVASAN
SUBMITTED BY : TANMOY JANA
M.SC. 1ST YEAR [I SEMESTER]
DEPT. OF FISHERIES SCIENCE
REGESTRATION NUMBER : 2020547018
ALAGAPA UNIVERSITY

2. INTRODUCTION
Rock pools (or 'tide pools') are rocky pools by the sea. They are mainly found in
the intertidal zone. They are filled with seawater during high tide, and exist as separate
pools at low tide. Rock pools are habitats of uniquely adaptable animals that have engaged
the special attention of naturalists and marine biologists. Sometimes due to heavy rain
salinity falls down and it become freshwater in nature. And some time rock pools may
present near the rivers or streams then it is called freshwater rock pool.
WHAT IS ROCK POOL?

3. ECOLOGICAL IMPORTANCE OF ROCK POOL
 As the tide recedes, not all of the coast is left behind dry. Depending on the type of rock, one can
find shallow or deep rock pools. They offer better survival chances for animals and plants that need
to be submerged all the time. Because each rock pool is different, they invite different communities.
Deep rock pools near the low tide, have few survival problems, whereas shallow rock pools near the
high tide, have many. Thus the pool's placing on the shore as well as its depth and size are important
factors.
 Deep rock pools provide shelter from waves, allowing fragile organisms to live on an otherwise
exposed rocky shore. Fragile animals are: sea slugs, shrimps, camouflage crabs, sea eggs, small
fishes. Fragile sea weeds are: Neptune’s necklace, pillow weed, cystophora, sea lettuce and many
others.
 For the snails that are able to survive in between high and low tide (periwinkle, nerita, melagraphia,
cats eye) a rock pool is not necessarily a better place because their predators are found there (dark
rock shell, white rock shell, trumpet shell). Large fish and octopus may find the rock pools too small,
lacking oxygen for breathing. Rock pools may collect fresh water during rain storms, which is worse
for shallow rock pools high up the shore where organisms must wait longer for the tide to return.
 Many small fishes use the rock pool as a shelter against the low tide, but as soon as the new tide
moves in, they leave the pool to wander around their much larger territories outside the pool, where
they find their daily food. Recent scientific research has shown that most of these small fishes stay
in the same pool all their lives. It is important to these fishes that they can hide inside the pool, in a
crevice, under an overhang or under a large stone.

4. This diagram shows four different rock pools. No 2 is a shallow high tidal pool in Leigh, where very few species survive:
slimy green algae and tiny Stiliger sea slugs. Pool 3 is an upper mid littoral splash pool in which the Neptune's necklace
seaweed survives. Pools 4 and 5 are deep lower mid littoral pools from Ocean Beach, near Whangarei Heads. They are
rich pools with many surviving plant species and sensitive species such as Cystophora torulosa and Pterocladia
capillacea.

5. DIFFERENT FACTOR INFLUENCING THE ROCK POOL
ECOSYSTEM
A. ABIOTIC FACTORS
TEMPERATURE: During the day, rock pools are
heated by the sun and warm up, but during the night they
are cooled. When water warms up, it does not pass the
warmth downward easily. A thermocline develops, which
is a sharp boundary between the warm water above and
the cool water deeper down.
SALINITY: As water evaporates from shallow pools, it leaves the dissolved minerals behind in the
remaining water. The sea's most common mineral is salt. So, every rock pool becomes saltier as its
water evaporates, but shallow pools towards the high tide, more so than others. Some pools show
salt crusts. Very few if any animals or plants can live there.
When it rains, fresh water drains into the rock pools and depending on its volume, a rock pool can
become too fresh for marine life. Fortunately, fresh water floats on top, being lighter than salt water.
Because it mixes only when stirred vigorously, animals and plants can often survive deeper down.

6. OXYGEN: Animals need oxygen for breathing, but
plants also need oxygen at night when they cannot make
their own. So the low tide at night is the most critical.
Fortunately most animals are inactive at night, using the
least possible amount of oxygen.
During the day, the plants may produce more oxygen than
is used by the animals and the oxygen level in the pool
may rise, rather than fall. See the graph on the right.
LIGHT: Light enters the pool on an angle from above. Deep pools may show a distinctly
shaded side, inviting a variety of red seaweeds. Narrow, steep pools may not get as much
daylight as wide ones, inviting shade-tolerant species to live near the bottom. Underneath
stones and inside crevices, where it is dark, one may find animals such as sponges and
seasquirts, that would otherwise not be able to compete with the plants on the sun-lit
surfaces

7. B. BIOTIC FACTORS
 COMPETETION FOR SPACE (SHELTER FROM SUN/ CAVE).
 COMPETETION FOR FOOD.
 ABILITY TO AVOID PREDATORS.
LOCAL PHYSICAL STRUCTURE AND ABIOTIC ENVIRONMENT
 In general, basins are filled with rain water, resulting in a highly diluted environment at the start
of the flood with conductivities below 10µS cm −1 (microsecond cm year−1), approaching those
of distilled water.
 The generally shallow rock pools, with water depth usually varying between 5 and 30cm, have
poor buffering capacity to environmental changes, closely follow air temperature, and also show
large diurnal fluctuations in pH and dissolved oxygen.

8. ROCK POOL FAUNA
 The Sea anemone, such as Anthopleura elegantissima, can clone to reproduce. The
process is called longitudinal fission, in which the animal splits in two parts along its
length. Some species, such as Anthopleura sola can fight for territory. The white
tentacles (acrorhagi) are for fighting. The acrorhagi contain stinging cells. The sea
anemones sting each other repeatedly until one (usually) moves.
 Some species of starfish have the ability to regenerate lost arms in time. Most species
must retain an intact central part of the body to be able to regenerate, but a few can
regrow from a single ray. The regeneration of these stars is possible because the vital
organs are in the arms.

9. ROCK POOL FLORA
Sea palms look much as palm trees. They live in the middle to upper intertidal zones in
areas with greater wave action. High wave action may increase nutrient availability and
moves the blades of the thallus, allowing more sunlight to reach the organism so that it
can photosynthesize. In addition, the constant wave action removes competitors.

10. CONCLUSION
MANY ROCK POOL NEAR POPULAR BEACHES HAVE LOST MOST OF THEIR SEAWEED AND
ANIMALS. THESE ARE SOME OF THE THINGS WE CAN ALL DO TO MAKE SURE THAT ROCK
POOLS KEEP SEAWEEDS AND ANIMALS :-
1. AVOID WALKING ON LIVING SEAWEED.
2. DO NOT PULL SEAWEEDS OR ANIMALS FROM THE ROCK.
3. NEVER REMOVE ANIMALS FROM THEIR HOME.
4. LEAVE INTERESTING SHELLS ARROUND THE ROCK POOLS AS MANY ANIMALS MIGHT
WANT TO USE THEM.

11. THANK YOU