The food and feeding habits of Polyprerus cncllicheri and Polypterus senegalus was carried out in the

months of September to October.

The food of 33 Polypierus endlicheri as observed include Tilapia species (89.3%), Eutropius niloticus

(28.6%), Mayfly nymph (39.3%), Dragon fly larva (56.6%) fish remains (21.4%) and detritus (7.1%). The

food of27 Polypterus senegalus as observed include Tilapia sp (88.4%), Eutropius niloticus (27.9%), may

fly nymph (23.3%), Dragonfly nymph (34.9%) remains (21.1%) detritus (23.3%). (9 page document)

The percentage occurrence of food item found in the stomach of Polypterus endlieheri is 93.3% while that

of Polyprerus senegalus is 67.4%. The dominance of Tilapia sp was establish in the study, and there is no

significant difference between the feeding habit of Polypterus endlicheri and Polyprerus senegalus

Maryam, Ahmed T.

Raji, Aminu

Saidu, Armed K.

English

Aquatic Commons

PREUMNARY STUDES ON FOOD AND FEEDNG HABTS
OFPOLYPTERUS NDUCHER AND
POLYPTERUS SENEGAWS N• LAKE CHAD
ABSTRACT
BY
AMINU RAJI; ARMED K SAIDU; AHMEI) T. MARYAM.
FEDERAL COLLEGE OF FRESHWATER
FISHERIES TECHNOLOGY BAGA
The food and feeding habits of Polyprerus cncllicherj and Polypterus senegalus was carried out in the
months of September to October.
The food of 33 Polypierus endlicheri as observed include Tilapia species (89.3%), Eutropius niloticus
(28.6%), Mayfly nymph (39.3%), Dragon fly larva (56.6%) fish remains (21.4%) and detritus (7.1%). The
food of27 Polypterus senegalus as observed include Tilapia sp (88.4%), Eutropius niloticus (27.9%), may
fly nymph (23.3%), Dragonfly nymph (34.9%) remains (21.1%) detritus (23.3%).
The percentage occurrence of food item found in the stomach of Polypterus endlieheri is 93.3% while that
of Polyprerus senegalus is 67.4%. The dominance of Tilapia sp was establish in the study, and there is no
significant difference between the feeding habit of Polypterus endlicheri and Polyprerus senegalus.
INTRODUCTION
Much of our current understanding of the
autecology's production and ecological role of fish
populations is derived from studies of the diet based
on analysis of stomach contents. Feeding is one of
the essential functions of any organisins, growth,
development and reproduction all take place at the
expense of energy, which is available in the
organism derived from the food they eat.
It is an established fact that animals including fish
perforni differently on different types of fbod. Fish
under the most favorable environmental conditions
will function and grow well if they get right quality
and quantity of food.
The type of food found in an area influences the
distribution, abundance and rate of growth of the
fish. Knowledge of the food of fish is very
important not only for the understanding of the
186
relationship between fish and its environment but
also to provide answers to the practical problems,
which arise in relation to human exploitation.
Considerable biological studies have been
undertaken and documented on some wild but
economically important tropical families in Lake
Chad e.g.
No such detailed and studies have been carried out
on Polypteridae.
The limited available biological information on
J'oiypterus species in the wild by Holden (1963)
was not enough. The aims and objectives of this
project work are to determine the type of food
takcii by Polypterus endlicheri_and Polypterus
senegalus found in Lake Chad and also to study
the degree of overlap in terms of food between the
two-sypatric species.
MATERIAL S AND METHODS
A total number of sixty specimens of genera
Polypterus were worked on from the catches of
local fishernien with the use of Malian trap and
longlines at the Dumba fishing village on the shore
of the Lake Chad between the periods of September
to October.
The fish were brought to the College Fish
Processing' Laboratory where the morphornetric
measurements were taken. They were then
weighed individually with the aid of beam balance.
The fish were dissected using dissecting sets, their
gut length was measured and the stomach contents
of the fish species were examined.
In analyzing the food the abundance of various
food items that were found in the stomach of these
fish was studied. The condition factor was
calculated according to Bagenal and Tesch, (1978).
K 100W
Where K = condition factor
W weight in gramine
L length in centimeter
DESCRIPTION OF THE STUDYAREA
Lake Chad present a large expanse of eutrophic
water body with tremendous living aquatic
resources that play significant roles in the socio
economic lives of the individuals and communities
within and outside its immediate regions of
location. The Lake lies within a semi arid
environment between Lat. 12° 140 20 N and long.
13° 15° 30E where water constitutes the most
limiting resource to development including food
production. The Nigerians share of the lake,
situated in the extreme North-East zone of the
187
country at a distance of about 230km from
Maiduguri, the Borno State capital city, lies
between Lat. 12018 i3048 N and Long.
13°18ç E 14°48c B, covering about 6660km2
'when the lake stabilizes at normal size of the lake
has been greatly subject to the influence of rainfall
and volume of water flowing the major rivers that
feed the basin (but it is believed that the
hydrological condition of the lake has improved
within the past one decade).
Lake Chad is among the richest fishing grounds in
the world and the Chad fisheries (comprising also
the lower reaches of the Chari and the Logone
with their flood plains as well as minor rivers
flowing into the lake) constitute one of the most
important inland fisheries in Africa.
There have been considerable studies on many
aspects of the fisheries of Lake Chad as an entity
or parts in the four countries (Chad, Nigeria,
Carneroon and Niger) that share the Lake.
Neiland (1990) presents a considerable review of
the available research materials on the fisheries of
the lake from pre 1960 to 1989. He revealed that
out of the 194 research works within the period,
26% were on the biology of the specific fish
species. 14% each were on general works and fish
resources and production while 12, 9, 8 and 1%
were on fisheries ecology, fishing practices and
technology processing and post harvest and
sociology/anthropology, respectively. Details of
some of these works are also contained in
the publication ofNeiland (1991).
RESULTS AND DISCUSSION
A total of 60 fish comprising of 33 spedmens of
Polypterus endlicheri and 27 Polypterus
senegalus were examined. Appendix 1 and 2
show the weight of fish in grains, the length in
centimeter. and the condition factor (k).
The average weight of Poljpterus endlicheri is
255.67g while that of Polypterus senegalus is
38.22g and the average condition factor of
Polvpierus senegalus is 0.96 while that of
Polypterus senegalus is 0.79 and condition factor is
higher in Povpierus senegalus, this might be as a
result of the bigger size of Polypierus endlicheri.
When the condition factor is 1 or nearer to 1, it
means that the fish are in good condition.
Table I shows that list of food items found in the
stomach of Polypierus endlicheri. Out of 33
specimens of Polypterus endlicheri only 3 have
empty stomach.
The various food items found in the stomach of
Polypterus endlicheri. in terms of number are
Tilapia constituting the highest food item
encountered in stomach 89.3% followed by
dragonfly nymp 53.6%. mayfly nymph 39.3%,
Eutropius niloticus 28.6%, fish remains 21.4%
and detritus 7.1%.
However, a subjective observation in tenns of
weight shows that Tilapia constitute the highest
followed by Eutropius, fish remain, dragonfly
nymph, mayfly nymph and detritus.
Table 2 shows the various food items found in the
stomach of Polypterus senegalus in terms of
nurnber these are Tilapia 88.4%, dragonfly nymph
34.9%. Eutrolpius 27.9%. mayfly nymph
CONCLUSION
Preliminary studies on food and feeding habits of
Polypterus species was examined. Thirtythree
specimens of Polypterus endlicheri with average
weight of 255.67g and 27 Polyplerus senegalus
with average weight of 3 8.22g were worked on.
188
23 .3%mayfly nymph 23.3%, Detritus 23.3% and
fishremains 21.1%.
From the result above, it can be seen that Tilapia
from the main food item of Polypterus endlicheri
in Lake Chad, whereas the work of Shotter and
Medaiyedu (1977) on the same fish in River
G-alma, Zaria reported that Barbus species forms
the highest food items followed by Schilbe
mystus, Tilapia species, Heinichromis
bii-nacutalus and Syndontis species respectively.
These differences in food preferences may be due
to habitat, that is Lake and River, availability of
certain type of food in the habitat. However, the
Polypterus endlicheri seem to share the
preference for Synodontis with Polypterus birchir
lapradel as reported by Holden (1963) in Sokoto
River.
Comparing the food of Polypterus endlicheri and
Polypterus senegalus, it can be seen that they have
the same food preferences, which mean there
should be competition between them since they
are sympatric.
However, the account of the fishermen that
catches the fish indicates that Polyplerus
senegalus are found close to the shore while
P013pterus endlicheri are caught mainly offshore,
thus utilizing the food in different zones of the
lakes.
These fish species were observed to be
carnivorous predators feeding mainly on other
fish species like Tilapia and Eutrolpius niloticus
insect larvae and detritus respectively.
Polypterus endlicheri found in Lake Chad -feed
type of food, there is no competition between
them because Polypterus senegalus are found
close to the shore and Polypterus endlicheri are
found offshore.
Table 3: Mean, weight, mean length and mean condition factor of Polypterus endlicheri
and Polypterus senegalus.
189
chiefly on Tilapia sp while tho found in the River
feed mainly on Barbus sp.
Even though, Polypterus endlicheri and Polypterus
senegalus found in Lake Chad feed on the same
Table 1: The type and frequency of occurrence of the identifiable food items found on
stomach of Polypterus endlicheri from Lake Chad.
= Percentage of total number of stomachs with identifiable food items
the
ITEMS TOTAL NO. OF
FOOD ITEMFOUND
% TOTAL NO.
FOUND
FISH SPECiES TILAP1A 25 33.78
Eutropius niloticus 8 10.81
INSECTS dragonfly nymph 15 20.27
Mayfly nymph 11 14.86
OTHER ITEMS fish remains 6 8.10
Detritus 2 2.70
Table 2: The type and frequency of the identifiable food items found in the stomach of
Pplterus sene.galus from Lake Chad.
= Percentage of total number of stomachs with identifiable food items.
JTEMS TOTAL NO. OF
FOOD ITEM FOUND
% TOTAL N
FOUND
Tilapia 38 47.50
Eutropius niloticus 12 15
NSECTS dragonfly nymph 15 18.75
Mayfly nymph 10 12.5
OTHER ITEMS fish remains 10 12.5
Detritus 0
Polypterus endhcheri
Mean weight 255.67g
Mean length 29.2cm
Mean condition factor (K) 0.96
Polypterus senegalus 38.22g
Mean weight 16.9cm
Mean length 0.79
Mean condition factor (K)
REFERENCES
Bagenal, T. B. and Tesh, F. W. (1978) Age and Growth In: Methods for Assessment of Fish Production
in Freshwater, 3 end. (T.B. Bagenal ed). Pp 101 136. Oxford, U.K. Blackwell Scientific
Publications.
Holden. M. J. (1963) The Populations of fish in dry season pools of Sokoto River Col. Off. Fish Pub.
London.No. 1965.
Neiland, A. E. (1990) Artisanal Fisheries of Chad Basin inAfrica. An information crisis. University
of Portsmouth, Portsmouth, U.K.
Neiland, A. E. (1991) An overview of fisheries research in Chad Basin ofAfrica 1920 1988. Including
a partially annotated bibliography CAMERA Respap. No.45 1991.
Shotter, R. A. and Medaiyedu, J. A. (1977) The parasites ofPolypterus endlicheri HECKEL from
River Galma at Zaria, Nigeria with a note on its food.
APPENDIX 1
MORPHOMETRIC MEASUERMENT AND
POLYPTERUS ENDL1CHERI
CONDITION FACTOR OF
SPECIMEN STANDA
NO. LENGTH
(CM)
RD WEIGHT
(GM)
GUT
LENGTH
CONDITION
FACTOR (K)
1. 29.6 247.6 23,3 0.9
2. 28.8 210.7 23.2 0.88
3. 30.0 290 24.2 1.01
4. 31.w 350 28.4 Lii
5. 30.0 240 24.1 0.88
1.016. 31.2 320 24.3
7. 26.5 250 21.5 1.31
8. 26.2 200 21.5 0.12
9. 29.8 240 23.4 0.9
10. 30.4 250 24.2 0.88
11. f 33.5 390 30.0 1.03
1.0512. 1 30.5 300 25.2
13. 31.5 390 - 286 1.2
14. 25.6 170 20.1 .01
15. 29.2 270 23.1 .08
1.35
1.27
16. 24.5 200 19.2
[17. 28.0 280 21.3
18. 29.5 280 23.2 1.09
19. 30.5 340 24.4 1.19
20. 30.0 250 24.2 0.92
21. 28.3 220 21.4 0.97
22. 28.5 250 22.1 1.07
23. 31.5 260 24.8 0.83
24. 35.5 400 29.4 0.89
0.8525. 28.1 190 23.0 -
26. 27.3 190 22.3 0.76
27. 27.0 150 22.0 0.76
28. 27.6 • 160 22.5 0.95
29. 27.6 201.8 22.5 0.76
30. 28.2 180 22.4 0.95
31. 28.0 210.6 • 21.4 0.8
32. 30.0 250 24.2 1.07
33. 30.5 300 25.2. 1.05
AVERAGE 255.67g 29.2cm 0.96
190
APPENDIX 2
MORPHOMETRIC MEASUREMENT AND
POLYPTERIJS SENEGALUS
CONDITION FACTOR OF
S/NO STANDARD
LENGTH
n)
WEIGHT
(gm)
GUT
LENGTH
CONDITION
FACTOR (k)
1. 16.6 34.2 11.7 0.74
2. 20.9 73.7 . 19.5 0.80
3. 17.2 46.6 12.1 0.91
4. 15.2 36.5 10.0 - 1.03
5. 17.5 34.7 12.4 0.64
6. 14.8 -. 23.0 9.2 0.70
7.
—
18.0 41.5 13.0 0.71
8. 18.1 44.4 13.1 0.74
9. 17.8 42.4 12.6 0.75
10. 17.0 44.1 12.0 0.89
11. 17.2 40.9 12.1 0.80
12. 17.4 35.0 12.3 0.66
13. 16.2 33.5 11.5 0.28
14. 15.4 27.3 10.1 0.76
15. 16.1 34.8 . 11.5 0.81
16. 16.5 26.9 10.2 0.73
17. 17.5 30.8 11.3 0.73
18. 14.7 38.9 11.6 0.86
19. 15.3 37.5 12.4 0.69
20. 17.4 22.1 9.1 0.69
21. 18.0 24.9 10.1 0.69
22. 19.1 46.3 12.1 0.87
23. 18.9 42.6 13.1 0.73.
24. 17.4 49,5 14.2 0.71
25. 17.8 45.1 13.8 0.66
26. 17.4 37.2 12.2 0.70
27. 17.8 43.4 12.5 0.76
Average 38.22g 16.5cm . 0.79
191
3.5
30
25
20
5I
10
5
0 n(0U)
Wc
>,-c0
>'
C -
VARIOUS FOOD ITEMS
Fig. 1. Relative abundance of various food found in the stomach of polypterus
endlicheri from Lake Chad
H
VARIOUS FOOD ITEMS
Fig. 1. Relative abundance of various food found in the stomach of polypterus
senegalus from Lake Chad
192
U)c,)
.o_0
-2Wc£.-. )Q.cE
(0
z0
Cl)C
FISH AND FISHERIES OF NORTHERN NIGERIA
Fig. 205. The Nigerian part of Lake Chad
193
I
HA
5LAt'US 10 THE
17H AND WEST
'(
•1•' ,.f Yt.
•. Y7i
'1 -
f J.,c
I 1f).4 1I.4t.v
'—..
41
.
I •1I \ - •' " 13
\•'\
N '\ G
._
4ff r fA1 0q)3
.
•
L
f:-..
• ' '-'1
' ••METE
•
\
• • ALAGUP
''
.
—. . ui) nor
('N(
- - :AKE :\
•1
.
. i4;• ' •' \ \ I
V
.
#• .i " '
i.it .t r
/WA1WA {c1.
• C
1 .ç';
•' 1:
— iAoG0 w t)i ¶
\( i,\
i: ti K!
NGE1
iic;i fl/\
Ek:AMA
t
•!'('. r
•:
1'
1 1kv
.4 . f
01
Legend
•j i PAPYPU9
9; fiAif
T.( fULGO
—. .. c $uA U)rJAL
—
' flOAt)C,
(J -rowti v;LLA(E
BOUt DM(
r \PY1W. AND SLAHDS
I4 - 12 0



Preliminary studies on food and feeding habits of Polypterus endlicheri and Polypterus senegalus in Lake Chad

http://aquaticcommons.org/1265/1/FISON2003_186-193.pdf

Preliminary studies on food and feeding habits of Polypterus endlicheri and Polypterus senegalus in Lake Chad

Abstract

Similar works

Full text

Available Versions

Aquatic Commons