International Journal of Marine Science 2015, Vol.5, No.13, 1-11
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61 specimens comprising about 19 % of the total
macroinvertebrates recorded. It was recorded in all the
experimental cages throughout the study months. The
species constituted about 29 % of the total individuals
observed in cage 1, 17 % in cage 2, 8 % in cage 3, 6 %
in cage 4 and 10 % in cage 5. The organism accounted
for about 31 % of the total macroinvertebrate
specimens recorded in the first month (February) of
study , 18 % of the total in the second month, 17 % of
the total specimens observed in the third and forth
months, and 13 % of the specimens recorded in fifth
month (July). Highest number of individuals of
M.
cumana
occurred in cage 1 and in the first month of
study, while least numbers were recorded in Cage 1
and in the month of July. The trend displayed by the
organism shows a quick rush to colonize the
experimental cages especially cage 1, with the number
of colonizing individuals varying with cage and time.
Table 3 Species recorded, time of appearance and cages of highest abundance. F = February, M = March, Ap = April, Ma = May, J = July
Phylum
Class
Family
Species
Month and Cage of
first appearance
Cage of highest abundance
and highest number
recorded
Total
Abundance
Mollusca
Gastropoda Melaniidae
Pachymelania aurita
F/All cages
1/23
56
Potamididae
Tympanotonus fuscatus
J/All cages
1/24
51
Neritidae
Neritina glabarata
Ma/1
½
3
Neritina kuramoensis
F/1
1/10
12
Bivalva
Tellinidae
Macoma Cumana
F/All cages
1/39
61
Tellinidae
Tellina nymphalis
F/All cages
1/10
32
Aloididae
Aloidis trigona
F/1
1/6
10
Avcidae
Mytilus edulis
Ma/1,3and4
Two individuals each in
cages 1,3 and 4
6
Arthropoda Crustacean Sesarmidae
Sesarma huzardi
Ma/1
An individual each in
cages1,2 and 5
3
Clibanaridae
Clibanarius africanus
F/All cages
5/10
33
Callinectis amnicola
F/Cages 1and4
4/3
4
Penaeidae
Penaeus notialis
F/All cages
3/7
23
Annelida
Polycheata Nereidae
Nereis lamellose
Ma/1,2and4
2/3
7
Nereidae
Nereis diversicolor
Ma/All cages
2/5
14
Nereidae
Nereis succinea
F/Cages 2 and 4
Two individuals each in
cages 2 and 4
5
Lumbrineridae
Lumbrinerides cingulata
Ma/Cage 4
Four individuals occurring
only in cage 4
4
Pachymelania aurita
ranked second in terms of
number of individuals recorded in the experiment and
accounted for 17 % of the total count. The organism
occurred in all the experimental cages throughout the
period of the study. It constituted about 17 % of the
total individuals observed in cage 1, 10 % in cage 2,
20% in cage 3, 12 % in cage 4 and 25 % in cage 5.
Overall monthly representation in the experimental
cages showed that the animal accounted for about
10 % of the total macroinvertebrate population
recorded in the first month (February) of study, 13 %
in the second month, 23 % in the third month, 17 % in
the forth month and 21 % in the fifth month. Highest
number of individuals of
P. aurita
occurred in cage 1
in the month of April, while least values were
recorded in Cage 2 in the second month (February).
The trend displayed by the organism is similar to that
of
M cumana
indicating a general preference for cage 1.
Tympanotonus fuscatus
was recorded in all the cages
throughout the study months. The 51 individuals
recorded accounted for about 16 % of the colonizing
macroinvertebrate population in the experimental
cages. Higher number of individuals occurred in cage
1 (24) and cage 5 (16), four individuals were observed
in cages 2 and 4, while three individuals were
recorded for cage 3. Monthly record of the total
number of individuals of the species in all the cages
indicates that the number of individuals increased
from eight in February to 12 in July. Ten individuals
