Journal of Threatened Taxa | www.threatenedtaxa.org | 26 August
2019 | 11(10): 14309–14317
Palynological analysis of faecal matter in
African Forest Elephants Loxodonta cyclotis (Mammalia: Proboscidea: Elephantidae) at Omo Forest Reserve, Nigeria
Okwong John Walter 1,
Olusola Helen Adekanmbi 2 & Omonu Clifford 3
1,2 Department
of Botany, Faculty of Science, University of Lagos, Akoka,
Lagos, 100213, Nigeria.
1,2 Center for
Biodiversity Conservation and Ecosystem Management, University of Lagos, Akoka, Lagos, 100213, Nigeria.
3 Forestry
Research Institute of Nigeria, P.M.B 5054, Jericho, Ibadan, Nigeria.
1 okwong56@gmail.com
(corresponding author), 2 helen_olu@yahoo.com, 3 clifford.omonu@gmail.com
Abstract: The factors affecting African Forest Elephants include
food availability, demand for ivory and changes in land-use. In order to
survive, they tend to traverse considerable distances in search of food; on
such occasions they are trapped and killed for their ivory. This present study is aimed at assessing the
faecal matter of elephants, and at providing information on the season of
ingestion and foraging preferences of these elephants. Faecal matter was collected at nine different
locations for one year before being processed and subjected to standard
palynological laboratory procedures. The
analyses showed that the samples had moderately abundant and diversified
palynomorphs. A total of 27 palynomorphs
belonging to 22 families with a total count of 2,895 accounting for 94.34% were
found to be eaten, while other plant fragments (epidermal cells, xylem vessel
elements, and seeds) accounted for 5.66%.
The wet and dry seasons accounted for 73.26% and 26.74% respectively. Epidermal cells and xylem vessel elements
recorded (70.76%) and (29.2%) during the dry and wet seasons,
respectively. In the palynological
analysis, pollen of Balanites wilsoniana, Desplatsia subericarpa, Chrysophyllum albidum, among others were recovered in the faecal
matter. Pollen analysis of faecal
matters provided no information about the quantitative composition of the
natural vegetation of elephants, but rather valuable information about their
diet. It is recommended that these preferentially foraged parent plants should
be cultivated on a large scale. This
would potentially reduce competition for food and movement of these animals to
other greener areas, consequently leading to poaching.
Keywords:
Diet, ivory, palynomorph types, pollen, sampling, southwestern Nigeria,
vegetation
doi: https://doi.org/10.11609/jott.4639.11.10.14309-14317
Editor: Analinda C. Manila-Fajardo, University of the Philippines Los Banos, Laguna, Philippines. Date of publication: 26 August 2019 (online &
print)
Manuscript details: #4639 | Received 16 October 2018
| Final received 29 July 2019 | Finally accepted 02 August 2019
Citation: Walter, O.J., O.H. Adekanmbi & O. Clifford (2019). Palynological analysis of faecal matter in African
Forest Elephants Loxodonta cyclotis (Mammalia: Proboscidea:
Elephantidae) at Omo Forest
Reserve, Nigeria. Journal of Threatened Taxa 11(10): 14309–14317. https://doi.org/10.11609/jott.4639.11.10.14309-14317
Copyright: © Walter et al. 2019. Creative Commons Attribution
4.0 International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by adequate credit to the author(s)
and the source of publication.
Funding: Research work
was funded by Princess Kaylani’s foundation, and the respective authors.
Competing interests: The authors declare no competing
interests.
Author
details: Mr. Okwong John
Walter is a PhD Student at the Department of Botany, University of
Lagos, Nigeria. He is also a scientist at Botanical society of Nigeria,
Palynological association of Nigeria and Center for Biodiversity Conservation
& Ecosystem Management, University of Lagos, Akoka,
Lagos, Nigeria. Dr. Olusola Helen Adekanmbi is a Senior Lecturer, working on
environmental management and pollution monitoring and is the research adviser
to number of PhD students. She is also
the Deputy Director Research & Innovation at the University of Lagos. Mr. Clifford Omonu
is a Research Officer at the Forestry Research Institute of Nigeria. He is
currently heading an out station in Omo Biosphere
Reserve, Ogun State. A UNESCO site managing the Strict Nature Reserve SNR. His
research interest include general wildlife management, protected area community
advocacy and environmental education with focus in Elephant conservation in
Nigeria.
Author
contribution: OJW
designed and conducted the present study.
CO assisted in the collection of samples, while OHA supervised the
research work with technical inputs as research adviser.
Acknowledgements: The authors would like to express sincere thanks to
Princess Kaylani’s Foundation and the Nigerian
Conservation Foundation towards ensuring the success of the project. We sincerely thank the staff of the
Department of Botany, especially those in the Palaeobotany and Palynology unit.
INTRODUCTION
The studies of faecal matter allows one to determine a
wide range of biological information about a creature, including its diet,
environment, health, and infections such as tapeworm. In combination with the analysis of pollen,
an abundance of information about diet, disease, and general health can be
acquired from such archaeological materials (Reinhard 1994). Not all faecal matter have the same potential
information due to taphonomic conditions. Seasonal changes in the diets of African
Forest Elephants Loxodonta cyclotis are difficult to quantify because of the
difficulty of observing the same animal regularly on a long-term basis. Using their trunks, elephants are skilled at
manipulating food and show strong preference for specific plant parts (i.e.,
bark, roots, leaves, and fruits; McKay 1973).
This selection is driven by factors like palatability, nutrient
composition, secondary and toxic plant compounds, physical defenses,
and handling time (Sukumar 1989).
Understanding the diet of elephants requires detailed information on the
specific plants they consume, but this information is rarely reported. This ideology instigated the study on how
pollen grains and other macro elements of plants could be used to reveal the
foraging preferences and period of ingestion of plants by African Forest
Elephants. These will provide
significant insights into ecological requirements relevant for the management
of wild elephant populations and their habitats and for the mitigation of
human-elephant conflicts, since their existence has been threatened as a result
of increased human population and anthropogenic activities. They are sometimes the only disperser of some
tree species, such as Desplatsia subericarpa and Balanites
wilsoniana.
The rate of seed germination of many forest plant species increases
significantly after passage through an elephant’s gut (Barnes et al. 1991). It is worth stressing that the pollen in
elephant coprolites gives a regional perspective of the palaeo-environment
since these animals travel long distances in search of food. Elephants’ coprolites reflect more regional
pollen sources than sediment analysis.
Also, elephants play a significant role in seed dispersal and
maintaining plant diversity (Campos-Arceiz &
Blake 2011). In spite of their
uniqueness and key role in forest ecosystems, African forest elephant
populations have depleted over the years owing to a number of factors including
ivory poaching and trade across the globe, habitat loss through the conversion
of land to agriculture and increasing competition for resources with growing
human populations (Maisels et al. 2013). In southwestern Nigeria, Loxodonta
cyclotis have become in danger of extinction in
many ecological zones while the remnant fragile population remains at risk of
been endangered. As the human population
increases more rapidly, the elephant kingdom is currently being broken down
into smaller units traversed by roads, human settlement and infrastructures,
thereby bringing elephants into conflict with humans. This is with a view to assisting people in
management to make strategic decisions for the effective conservation of our
forest reserves and animals. A better
understanding and knowledge of grazing behaviour and foraging preferences of
some plants by elephants will make it possible to develop a coherent strategy
for the conservation and management of the forest reserve.
MATERIALS AND METHODS
Description of the Study Area
Omo Biosphere Reserve is located between 6’35’09.90
–7’05’04.94 0N and 4’19’21.28–4’40’21.16 0E (Fig. 1) in
the south-west of Nigeria, about 135km north-east of Lagos, about 120km east of
Abeokuta and about 80km east of Ijebu Ode (Ola-Adams 1999). The reserve shares a common boundary in its
northern part with Ago Owu and Shasha
forest reserves in Osun State. It also
has a common boundary with Oluwa Forest Reserve in
Ondo State (Karimu 1999); and covers 130,500ha of
land (Ojo 2004).
Vegetation
The study locations are currently open vegetation that
comprise tree species such as Celtis zenkeri, Diospyros dendo, Cleistopholis patens, Anthonathia
macrophylla, Ficus exaserata,
Canarium scheveinfurthii, Brachystegia eurycoma, Albizzia ferruginea, Cola negrica, Aistonia boonei, Ricinodendron heudelotti, Cordia millenii, Diospyros nigerica, Desplatsia subericarpa,
Terminalia superba, Humeria
umbellate, Musanga cecropioides,
Entandrophragma angolense,
Diospyros monbuttensis, Celtis
brownie, Khaya ivorensis, Ficus mucuso, Macaranga barteri, Celtis mildbraedii, Pycanthus angolense, Paspalum viginatum, among others. The study area is also composed of herbs,
climbers, epiphytes, stranglers, saprophytes and parasites (Adamson 1996). The reserve is in the mixed moist
semi-evergreen rainforest zone. The
northern parts of the reserve are relatively dry with typical species such as Sterculiar hinopetala. Nauclea diderrichii and Balanites wilsoniana
are common in the wetter central parts (Ola-Adams 1999). As a result of continuous human activities,
mainly logging and farming for almost a century, the vegetation pattern in Omo has changed remarkably.
The reserve now carries monocultures of Gmelina
arborea, Tectona grandis, Theobroma cacao, and arable farmlands. Natural forests of varying degrees of
disturbance and a 460-ha strict nature reserve (SNR) which was established in
1946 as an inviolate plot but later designated an SNR also exist. The SNR is in Area J1 by Omo
River, just a few kilometers south of the confluence
of Omo and Owena rivers in
the north-central part of the reserve.
Sample collection
One-hundred-and-eight faecal matters were collected
monthly, from nine locations for a period of 12 months. The faecal matter was collected by removing
the upper surface as well as the lower surfaces to form a thin section, thereby
reducing the number of contaminants. The
fresh faecal matter was then placed into sterilized plastic bags and then
weighed and stored in tightly closed sterilized containers with a small amount
of alcohol (70%) to avoid microbial growth and then frozen in the
laboratory. This sampling period was
divided into the wet and dry seasons.
The strongest and the first wet period lasts between April and July
while the second and weaker wet period between September and November. In between these wet periods is a relatively
dry period in August to September commonly referred to as the ‘August
Break’. The main dry season lasts from
December to March and is usually characterized by harmattan winds from the
north-east trade winds during November.
Laboratory analysis
Samples were placed into 10ml test tubes and washed
using distilled water by centrifugation and decantation to remove alcohol. Potassium hydroxide (KOH) treatment was
conducted for 10g of each faecal sample to remove humic
materials and soften the other organic material. About 10ml of 5% KOH was added to each sample
in the beaker and heated for several minutes.
Samples were then sieved with a 1mm mesh to remove large organic
particles that were then discarded. The
remaining sample was placed in 15ml plastic screw-topped centrifuge tubes and
centrifuged. The sample was then rinsed
with distilled water and centrifuged multiple times. The residue was subjected to acetolysis method (Erdtman
1969). The acetolysis
mixture of nine parts of acetic anhydride and one part of sulphuric acid (H2SO4)
was prepared. This mixture was then
poured into the tubes containing the residue and, boiled in a beaker at
100 ͦC for five minutes and was stirred
occasionally with a glass rod. After
cooling, the mixture was centrifuged at 2000rpm for five minutes. The liquid supernatant was then decanted
leaving only the palynomorphs in the tube.
Samples were then stored in 100% glycerin to
prevent the palynomorphs from drying out.
From stock mixture, samples were collected and mounted on slides and
studied under 40x objective lens magnification using an Olympus BX43 light
microscope. A micropipette was used to
pipette two drops of the prepared residue into a well-labeled
slide and was stirred with the tip of the micropipette for even
distribution. The coverslip was placed
gently on the residue in a way to prevent the formation of air bubbles. The slide was sealed using a commercial nail
lacquer and to make a semi-permanent slide.
The prepared semi-permanent duplicated slides were then studied
qualitatively and quantitatively using an Olympus BX43 light microscope under
(400x magnification).
Taxonomic Identification
The identification of palynomorphs was made by
comparing with some pollen albums, relevant journals (Sowunmi
1995; Gosling et al. 2013), and pollen reference slide collection in the
Palynology and Palaeobotany Laboratory, Department of Botany, University of
Lagos. Photomicrography of some of the
identified palynomorphs was taken with the aid of a Motic
2300 digital camera. Pollen was
identified up to the family level and where possible up to the species
level. Those that were unidentifiable
due to their broken nature were referred as indeterminate.
RESULTS AND DISCUSSION
Analyses showed that the samples have moderately
abundant and diversified palynomorphs.
The elephants consumed different plant species with varying degrees of
preferences. Twenty-seven palynomorphs
belonging to 22 families accounting for 94.34% were found to be eaten (Table
1). These Families include Zygophyllaceae which accounts for 882 (32.2%), Poaceae 410 (14.93%), Tiliaceae
295 (10.8%), Fabaceae 162 (5.91%), Irvingiaceae 135
(4.94%), Amaranthaceae 108 (3.95%), Lamiaceae 99 (3.62%), Asteraceae 85 (3.11%), and Calophyllaceae 69 (2.48%) while the least families are Sapindaceae 5 (0.18%) and Mimosaceae
4 (0.14%). Epidermal cells and xylem
vessel elements recorded (70.76%) and (29.2%) during the dry and wet seasons,
respectively. This has provided
information on the season during which this large terrestrial mammal debarks
trees more. Seeds were recovered in the
faecal matter during sample preparation.
The seeds recorded all-time high during the dry season (November–March),
but few were also recorded during the end of the wet season
(August–October). The occurrences of these
palynomorphs are displayed on a Tilia™ graph (Fig.
2).
Elephants browse and graze on a variety of plants but
the time spent foraging and the proportions of the plants consumed vary
depending on the season and availability (Fig. 2). The ratio of recovery of pollen grains in the
faecal matter between Poaceae (grass), herbs (Tridax procumbens),
and higher plants suggest that Loxodonta cyclotis spent more time browsing than grazing despite
the availability of grass in both the wet and dry seasons (Fig. 2). Also, the occurrences of Mangifera
indica, Desplatsia subericarpa, Balanites wilsoniana among others in their faecal matter conforms
to the assertion made by Amusa et al. (2017) in which
he reported that the African Forest Elephant is mostly a browser and frugivore
rather than the grazing and browsing habit exhibited by the Savanna Elephant.
The drastic increase observed in Poaceae, Asteraceae,
Zea mays, and Tridax
procumbens, however, indicate an obvious change
in feeding preference with grazing becoming more important during the wet
season. Browsing materials such as Zea mays, Parkia
biglobosa, Mangifera indica, Chrysophyllum albidum, among others were therefore abundant in the
dry season compared to the wet season (November–March).
The pollen analysis revealed that fruit was an
important component of the diet, while Balanites
wilsoniana is the most preferred plant for forage
by forest elephants especially in the dry season, despite its unpleasant
smell. Its recovery in these
studies may suggest that at this time of the year a maximum number of plant
species are flowering, while some are fruiting.
Fruits such as Irvingia gabonensis, Chrysophullum albidum, Parinari excelsa, among others are characterized
by firm, dry, dense flesh, and are therefore rich in lipids and proteins (Mckey 1975).
Furthermore, the analyses revealed that during the second half of the
main dry season, the lean season for most animals, there was a peak in fruiting
of animal-dispersed tree species.
Throughout this period forest elephants move from their preferred
secondary vegetation, as well as the logging sites in which the pollen of Zea mays (March–May) and Treculia
africana (July–December), ELaeis
guineensis (Febuary-May)
were used as a pointer, to denote the period at which the African Forest
Elephants encroaches on farmlands where fruiting trees and crops of favoured
species are to be found. This assertion
is also supported by Merz (1986), Barnes et al. (1991), and White (1994). According to Chapman et al. (1992) the tree species,
Balanites wilsoniana
substantiated this hypothesis with germination trials on fresh and ingested
seeds of eight trees and one species eaten by forest elephants. Such research has led to the understanding
that several tree species could become extinct in the absence of forest
elephants.
The family Poaceae were the
second largest group that were found to be eaten. Poaceae abundances
can be attributed to its ubiquitousness and their
ability to produce in large quantities.
The clear preference for grass over browses exhibited by the elephant in
the wet season (April–October) is probably related to the protein content of
the food available, as a result of high nutrient content, low toxins, and fibre
contents (Lindsay 1994), it also provides a return per unit time feeding that
is higher than browse. It lacks certain
essential nutrients, however, and at maturity its nutrient content becomes very
low. Their low recovery in the dry
season could be linked to the reduction in moisture content which becomes more
fibrous and abrasive, hence causing increased wear on teeth and a decline in
digestive efficiency. This supports the
view of (McCullagh 1969) that there is a decrease in the digestibility of
protein when the protein content of a food item is low and the fibre content
high. These support the claim made by
Sinclair (1975) that this is apparently a limiting factor in any
herbivore/resource relationship. This may account to some extent for the large
amounts taken, as the elephant at the start of the wet season, may have been
choosing the component with the highest protein level. The elephants graze throughout the year but
grazing activity becomes unimportant when grass becomes dry and coarse. It could also be argued that elephants are
primarily grazers because large quantities of grass are eaten even when large
quantities of browse are available. It
does not seem that elephants have been forced to adopt a primarily grazing
habit, as asserted by Sikes (1971), but have in fact always been grazers, and will
always graze when large enough quantities of grass are available; yet factors
such as digestibility, quality of food and ease of gathering also have to be
taken into consideration. Laws (1970)
stated that elephants when feeding on large quantities of young grass take bark
as a form of roughage. The increasing
number of epidermal cells and xylem vessel elements recovered in the month of
May and (November–February) supports the assertion made by Laws (1970). The elephants debarked trees both in wet and
dry seasons, but more particularly during the dry season, possibly because of
the increased translocation of food substances from the roots to the new
flushing leaves.
Desplatsia subericarpa Bocq. was the third most foraged species and was found to
be abundant during the end of the wet season and the beginning of the dry
season. It bears large fruits with a
hard seed coat. The pollen analysis
revealed that the African Forest Elephants are attracted to large fruits, as a
result of their body size. Furthermore,
there was a positive correlation between herbivore body size, the size of food
intake and dietary breadth, but still dependent on the diversity and
composition of the plants available.
These highly frugivorous diets make them particularly formidable
dispersers of seeds which could be referred to as ‘megafauna-syndrome’, i.e.,
plants with large fruits and seeds that may have evolved to attract large
herbivores to consume and disperse them.
Crops which include Amaranthus sp., Zea mays, Mangifera indica, Elaeis guineensis, and Fabaceae were also found
to be eaten and intensively used by the rural population. Their abundances in the faecal matter
indicate farmland incursion by the African Forest Elephants during the months
of February–May. Despite the large array
of plants available for forage in the reserves, forest elephants still consume
and destroy farm produce. This attests
to the fact that the African Forest Elephants are species specific when it
comes to their foraging preferences.
Therefore, it should come as no surprise that elephants have an
attraction for crops which are found to be nutritious and palatable, thus
resulting in human-elephant interactions and sometimes death for both parties.
Habitat fragmentation, however, increases the contact between elephants and
agriculture, and the intensity of crop-raiding is usually higher in more
fragmented habitats.
Pollen grains of Callophyllum
inophyllum, were also recovered, this plant has
been reported by several authors as toxic.
Their presence in the faecal matter signifies that the African Forest
Elephants take in toxic plants to balance their nutritional requirements. Therefore, detailed studies should be carried
out on the nutritional value vs toxicity, and the mechanisms behind these
choices. Some plants appeared to be fed
on only incidentally, perhaps when the species was being browsed. The plants—Acacia sp., Pancovia turbinata,
Mimosaceae, Parinari exelsa, Pinus caribaea, Pentadesma butyracea, and Omphalocarpum ahia—were
less than one percent in representation.
These were mostly the smaller sized fruits which were commonly eaten by
other animals, thus they may form a valuable supplement to the diet, and also
mainly for their water content. This
usually happens when they traverse a considerable distance in search of food in
areas where there is little or no presence of water.
The presence of xylem fibers
in the samples supports the claim made by Sukumar (1989) that the consumption
of bark helps to cover the calcium needs of elephants, and may consequently
serve more than just for satisfying hunger.
Furthermore, there was an abundance of fungal spores recovered. This denotes that the Feacal
matter may have retained some moisture during defecation by the African forest Elephants
which favours fungal growth. The high
relative humidity in the study location may have allowed for greater moisture
retention, making it ideal for fungal invasion.
The information obtained from the faecal matter using
the palynological method helped to describe the diet of Loxodonta
cyclotis and to understand the paleo-environment
of the study location. Therefore, these
selected plants should be cultivated on a large scale in our forest reserves to
restrict the movement of African Forest Elephants in search of food, which can
lead to poaching as well as human-elephant interactions. Our forest reserves without the African
Forest Elephants would be less in species richness and less structurally
diverse. Likewise, the African Forest
Elephants affect the complexity of the forest by spreading ingested seeds
during defecation and help maintain open areas for the reflection of high light
intensity near the forest floor, leading to the proliferation of grasses,
climbers, shrubs, and young trees to spring up.
Nevertheless, conservation concepts based on strictly intellectual or
aesthetic values understandably may have little meaning to local villagers who
have to struggle for their existence (Nepal & Weber 1995). In order to end the negative interactions
between African Forest Elephants and the human populace in rural areas,
multidisciplinary approaches must take into account the requirements needed for
both elephants and humans so as to achieve sustainable forest management goals.
CONCLUSION
Feeding and nutritional ecology is key to elephant
conservation. There is a need for the
conservation and management of certain species of trees and grasses for the
continued existence of forest elephants in the concerned forest reserves. It is recommended that these preferentially
foraged parent plants should be cultivated on a large scale. This would potentially reduce competition for
food and movement of these animals to other greener areas, consequently leading
to poaching. Also, for a qualitative and
quantitative assessment the habitat characteristics, techniques and data from
many different disciplines must be combined; however, there is a need for
continuous sensitization, support and empowerment of members of the host
communities through community social responsibility initiatives to make sure
they take part in the conservation and afforestation. Furthermore, nature conservation issues must
be dealt with by considering also the needs of humans, since the existence of a
native human population in any place involves complex interactions of ethnic,
social, economic, political, historical, and biological aspects that exceed a
strictly ecological approach. These will
pose a positive outcome for the African Forest Elephants in the days ahead.
Table 1. The frequency and percentage composition of
palynomorphs recovered from faecal matter of Loxondata
cyclotis.
|
Palynomorph
types |
Family |
Jan |
Feb |
Mar |
Apr |
May
|
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Total |
% |
1. |
Amaranthus
sp. |
Amaranthaceae |
6 |
5 |
41 |
31 |
3 |
4 |
8 |
6 |
1 |
2 |
1 |
0 |
108 |
3.95 |
2. |
Mangifera indica L. |
Anacardiaceae |
0 |
6 |
10 |
12 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
29 |
1.06 |
3. |
Elaeis guineensis Jacq |
Arecaceae |
0 |
21 |
4 |
0 |
7 |
0 |
3 |
2 |
1 |
0 |
0 |
0 |
38 |
1.39 |
4. |
Tridax procumbens L. |
Asteraceae |
0 |
0 |
0 |
6 |
5 |
4 |
1 |
16 |
0 |
0 |
0 |
3 |
35 |
1.28 |
5. |
Asteraceae type |
Asteraceae |
0 |
0 |
0 |
0 |
9 |
22 |
11 |
0 |
1 |
3 |
4 |
0 |
50 |
1.83 |
6. |
Calophyllum inophyllum L. |
Calophyllaceae |
0 |
0 |
0 |
21 |
19 |
15 |
11 |
0 |
0 |
0 |
2 |
0 |
68 |
2.48 |
7. |
Parinari excelsa Sabine |
Chrysobalanaceae |
8 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
2 |
10 |
0.36 |
8. |
Pentadesma butyracea Sabine |
Clusiaceae |
0 |
0 |
0 |
14 |
0 |
0 |
2 |
0 |
0 |
0 |
0 |
0 |
16 |
0.58 |
9. |
Parkia biglobosa(Jacq) R. ex Don-H.C |
Fabaceae |
0 |
6 |
11 |
9 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
27 |
0.98 |
10. |
Acacia
sp. |
Fabaceae |
0 |
1 |
2 |
2 |
1 |
0 |
1 |
1 |
0 |
0 |
0 |
0 |
8 |
0.29 |
11. |
Senna
hirsuta L. |
Fabaceae |
0 |
0 |
0 |
0 |
0 |
0 |
10 |
0 |
4 |
15 |
4 |
1 |
34 |
1.24 |
12. |
Fabaceae |
Fabaceae |
0 |
1 |
7 |
0 |
4 |
8 |
28 |
36 |
2 |
0 |
3 |
4 |
93 |
3.40 |
13. |
Sacoglottis gabonensis (Baill.)
Urb. |
Humiriaceae |
6 |
0 |
0 |
0 |
0 |
0 |
15 |
11 |
2 |
2 |
0 |
0 |
36 |
1.31 |
14. |
Irvingia gabonensis (Aubry
Lecomte) |
Irvingiaceae |
10 |
42 |
12 |
19 |
6 |
10 |
9 |
9 |
12 |
2 |
1 |
3 |
135 |
4.94 |
15. |
Vitex
sp. type |
Lamiaceae |
0 |
11 |
23 |
50 |
0 |
0 |
15 |
0 |
0 |
0 |
0 |
0 |
99 |
3.62 |
16. |
Mimosaceae
type |
Mimosaceae |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
4 |
0.14 |
17. |
Treculia africana Decne. |
Moraceae |
0 |
0 |
2 |
0 |
0 |
0 |
3 |
8 |
7 |
12 |
7 |
0 |
39 |
1.42 |
18. |
Pinus
caribaea Mor. |
Pinaceae |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
0 |
8 |
0 |
0 |
10 |
0.36 |
19. |
Poaceae |
Poaceae |
0 |
2 |
5 |
18 |
125 |
55 |
42 |
38 |
30 |
9 |
3 |
0 |
327 |
11.9 |
20. |
Zea
mays L. |
Poaceae |
0 |
0 |
15 |
26 |
42 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
83 |
3.03 |
21. |
Borreria sp.
|
Rubiaceae |
0 |
0 |
1 |
15 |
5 |
0 |
2 |
3 |
1 |
1 |
0 |
0 |
28 |
1.02 |
22. |
Nauclea diderrichii (De Wild. & Th. Dur.) |
Rubiaceae |
0 |
4 |
12 |
1 |
0 |
7 |
2 |
12 |
4 |
18 |
0 |
0 |
60 |
2.1 |
23. |
Pancovia turbinata Radlk. |
Sapindaceae |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
2 |
1 |
0 |
0 |
5 |
0.18 |
24. |
Chrysophyllum albidum G.Don. |
Sapotaceae |
0 |
5 |
24 |
29 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
60 |
2.19 |
25. |
Omphalocarpum ahia A.Chev. |
Sapotaceae |
0 |
0 |
3 |
7 |
0 |
4 |
5 |
0 |
0 |
0 |
0 |
0 |
19 |
0.69 |
26. |
Desplatsia subericarpa (Bocq) |
Tiliaceae |
0 |
0 |
1 |
0 |
21 |
1 |
145 |
104 |
15 |
4 |
3 |
1 |
295 |
10.8 |
27. |
Balanites wilsoniana Dawe & Sprague |
Zygophyllaceae |
1 |
65 |
271 |
494 |
32 |
0 |
0 |
2 |
6 |
4 |
5 |
2 |
882 |
32.2 |
28. |
Pollen Indeterminate |
Pollen Indeter. |
0 |
0 |
0 |
0 |
0 |
0 |
15 |
0 |
0 |
0 |
1 |
0 |
16 |
0.58 |
|
|
Total pollen count |
31 |
169 |
445 |
755 |
280 |
131 |
330 |
251 |
89 |
164 |
34 |
52 |
2731 |
94.3 |
29. |
Xylem fibers |
Plant Fragment |
13 |
16 |
0 |
0 |
20 |
0 |
0 |
0 |
0 |
0 |
17 |
11 |
78 |
2.84 |
30. |
Seeds |
Plant Fragment |
1 |
7 |
4 |
0 |
0 |
0 |
0 |
9 |
3 |
13 |
11 |
19 |
53 |
2.82 |
Total plants fragments |
14 |
23 |
4 |
0 |
20 |
0 |
0 |
9 |
3 |
13 |
38 |
30 |
154 |
5.66 |
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REFERENCES
Adamson, K.Y. (1996). Towards an environmental action plan for Ogun State,
Draft Final Report. World Bank Assisted Project, 139pp.
Amusa, T.O., C. Omonu & N.J.
Newton (2017). Population status and distribution
of Forest Elephants (Loxodonta cyclotis Matschie, 1900)
in Okomu National Park and Omo
Forest Reserve. Journal of Research in Forestry, Wildlife & Environment
9(2): 44–56.
Barnes, R.W., L. Barnes, M.T. Alers
& A. Blom (1991). Man determines the distribution of elephants in the
rain forests of northeastern Gabon. African
Journal of Ecology 29: 54–63. https://doi.org/10.1111/j.1365-2028.1991.tb00820.x
Campos-Arceiz, A. & S.
Blake (2011). Mega gardeners of the forest –
the role of elephants in seed dispersal. ActaOecologica
37: 542–553. https://doi.org/10.1016/j.actao.2011.01.014
Chapman, l.J.,
C.A. Chapman & R.W. Wrangham (1992). Balanites
wilsoniana: elephant dependent dispersal. Journal
of Tropical Ecology 8: 275–283. https//doi.org/10.1017/s0266467403003638
Erdtman, G. (1969). Handbook of Palynology:
Morphology-taxonomy-ecology: An Introduction to the Study of Pollen Grains and
Spores. Hafner Publishing Co, New York, 486pp.
Gosling, W.D., C.S. Miller &
D.A. Livingstone (2013). Atlas of the tropical West African pollen flora. Review of Palaeobotany
and Palynology 199: 1–135. https//doi.org/10.1016/j.revpalbo.2013.01.003
McKay, G.M. (1973). Behavior
and ecology of the Asiatic elephant in southeastern
Ceylon. Smithson Contribution Zoology 125: 1–113. https://doi.org/10.1007/s1184-008-0466-4
McKey, D. (1975). The ecology of coevolved seed dispersal systems. In: Gilbert, L.E. & P.H. Raven (eds.)
Coevolution of Animals and Plants. University of Texas Press, Austin, 246pp.
Karimu, S.A. (1999). The role of surrounding communities on the management
of Omo Forest Reserve. Consultant report for FORMECU,
Federal Departmentof Forestry, Abuja, Nigeria, 47pp.
Laws, R.M. (1970). Biology of African Elephants. Science Progress
Oxford 58: 251–262.
Lindsay, W.K. (1994). Feeding ecology and population demography of African
elephants in Amboseli, Kenya. Ph.D. Dissertation, Cambridge University, 244pp.
Maisels, F., S. Strindberg, S. Blake, G. Wittemyer,
J. Hart & E. Williamson (2013). Devastating Decline of Forest Elephants in Central
Africa S-O Kolokotronis, PLoSONE
8(3): e5946. https://doi.org/10.1371/journal.pone.0059469
McCullagh, K.G. (1969). The growth and nutrition of the African elephant II:
the chemical nature of the diet. East African Wildlife Journal 7: 91–97.
Merz, G. (1986). The status of the Forest Elephant Loxodonta
africana cyclotis, Matschie, 1900, in the Gola Forest Reserves, Sierra Leone.
Biological Conservation 36: 83–94. https://doi.org/10.1016/0006-3207(86)90103-5
Nepal, S.K. & K.E. Weber (1995). Managing protected areas under conditions of conflict:
selected case studies from China, Myanmar, Nepal, Philippines and Thailand.
Asian Institute of Technology, Bangkok, HSD Monograph, xvii+225pp.
Ojo, L.O. (2004). The fate of a tropical rainforest in Nigeria: Abeku sector of Omo Forest
Reserve. Global Nest 6(2): 116–130. https://doi.org/10.30955/gnj.000247
Ola-Adams, B.A. (1999). Biodiversity Inventory of Omo
Biosphere Reserve, Nigeria. Country Report on Biosphere Reserves for
Biodiversity Conservation and Sustainable Development in Anglophone Africa
(BRAAF) Project, 351pp.
Reinhard, K.J. (1994). Sanitation and parasitism at Harpers Ferry, Virginia.
Journal of Historic Archaeology 28: 62–67.
Sikes, S.K. (1971). The Natural History of the African Elephant. Weidernfeld and Nicolson, London, 397pp.
Sinclair, A.E. (1975). The resource limitation of trophic levels in tropical
grass land ecosystems. Journal of Animal Ecology 44: 497–520.
Sowunmi, M.A. (1995). Pollen of Nigeria plants: woody species. Grana 34:
120–141. https://doi.org/10.1080/00173139509430002
Sukumar, R. (1989). The Asian Elephant: Ecology and Management. Cambridge University Press, Cambridge, 255pp.
White, L.J.T. (1994). Sacoglottis gabonensis fruiting and the seasonal movements of
elephants in the Lope´ Reserve, Gabon. Journal of Tropical Ecology 10:
121–125.