Zoological Sciences

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Abundance of Rodent on Different Land Management Intervention in Simien Mountains National Park, North Ethiopia
(Addis Ababa University, 2018-10-04) Deksios Derbe; Jebessa Habte (Professor)
This study deals with the abundance rodents in different land management intervention. Overgrazing is one of the conservation challenges of the Simien Mountains National Park . Overgrazing has been devastating the fragile afro-alpine Ecosystem. The objective of this study was to identify habitat quality and abundance of rodent by recording the new rodent hole and the common mole rat hill between May, 2017 (wet season) and January and February 2018 (dry season), assessed thirteen transect lines in average 2-4 km each. In more rodents captured were investigated in six major sites (within twelve) sub sites and the grids were established within representative vegetation covers.During dry season, five species of rodents Lophuromys flavopunctatus, Arvicanthis abyssinicus, Stenocephalemys grisiecauda, Otomys typus,Mus mahomet and one species of insectivores, Crocidiura baileyi, were recorded. There was significance variation in habitat quality among different land management intervention fresh rodent holes and common mole rat hills (p<0.002 and P<0.003), respectively. ANOVA analytical test result also indicated that rodents’ distribution were significantly different with different land management such as moderate, slightly grazed and overgrazed habitats across afro-alpine ecosystem of Simen Mountains National Park. There was also variation in species abundance in grazed, unglazed and completely grazed land management system. The highest abundance was Arvicanthus abysinicus 56% six major sites; in twelve subsets no rodent was recorded in overgrazed Wezahla one low abundance C.baileyi 0.6%. Density of rodents highest in Alchemilla plant species 8/km2and 0 in overgrazed Hypericum revolutum plant species. There was significant different in rodent abundance (P<0.04) in different land management intervention. In general, grazing pressure were negatively affected the habitat quality of rodent and common mole rats' abundances. . Therefore, to reduce overgrazing, it is recommended to strength habitat conservation to gain habitat quality. To follow participatory conservation reduce overgrazing allowing rotational cut and carry system with limited time bound exclude core area and it should be applied in local bases.
Assessing Invertebrate Biodiversity in Gullele Botanic Gardenduring Wet Season.
(Addis Ababa University, 2019-09-09) Abdissa, Shoma; Mengistu, Seyoum (Professor)
Gullele Botanic Garden contains diverse types of invertebrates. The diversity, distribution, frequency, density and abundance of these invertebrates were investigated using 28 quadrats which were located at different habitat types. The study found that Gullele Botanic Garden support the presence of invertebrates in large quantity in mixed forest habitat. A total of 2854 invertebrate specimens belonging to 42 families were collected and recorded in the Gullele Botanical Garden. Higher diversity and evenness of invertebrates were observed in the mixed foresthabitat. On the other hand, the least evenness and diversity of invertebrates was observed in the grassland forest habitat in the study season. Based on jaccard's similarity index, the highest similarity was observed between mixed forest and grassland forest habitats.. The lowest similarity was observed between natural forest habitat and artificial forest habitat. Abundance of food on species of vegetation, stability of the habitats, human activities and settlement inside determined invertebrate diversity in the study areas.During data collection in Gullele Botanic Garden, careful observation showed that invertebrates had both positive and negative effect for humans, animals and insects. The positive effects were increasing soil fertility(earthworms),nutrient cycling(ants),increasing the rate of soil nutrient cycling(beetles) and indicators of environmental change and habitat disturbance(insects). Conversely, the negative effects were plant drying(termites) and attacking roots,trunks,stems,leaves, flowers ,seeds ,fruits and saps of vascular system(phytophagous invertebrates).
Avian Diversity and Abundance in Addis Ababa Abattoirs, Addis Ababa Ethiopia
(Addis Ababa University, 2019-09-09) Bekele, Rahel; Afework, Bezawork (PhD)
Study on Avian diversity and abundance in Addis Ababa Abattoir was carried out from February 2019 to July 2019. The Addis Ababa abattoir is a home to different kinds of birds due to the presence of scraps of animals in abattoirs. Point count method, was employed to record the diversity and relative abundance of individual bird species. The site supports eight species of birds that are grouped under three orders and four families. Know a day six of them are common in the area. Themost commonly observed avian species were hooded vulture, (Necrosyrte monachus), Marabou stork, (Liptoptilos crumeniferus) Wattled Ibis, .(Bostrychia carunculata) pied crow, (Corvus capensis) African white backed vulture (Corvus albus),and sacred Ibis ( Threskiornis aethiopicus) The abundant species were hooded vulture and African white backed vulture. Dry season had the highest species diversity and evenness (H=4.64), (E=0.59) and Species abundance (4557).The lowest species diversity, and abundance were recorded in wet season (H=2.4, E=0.18, and species abundance =1073, respectively). Feeding activity was from 10:30 – 11:30h at the mornning. The urbanization and cleared scrapes of animals or less amount of food availability affected bird community in depriving roosting trees. Most of the vultures were observed coming from south west direction of the study area.
Diversity, Distribution and Conservation Status of Small Mammals of Chilalo-Galama Mountains Range, Southeastern Ethiopia
(Addis Ababa University, 2018-03-04) Kasso Mohammed; Bekele Afework (Professor)
A study on diversity, distribution and conservation of small mammals was conducted in Chilalo-Galama Mountains Range from August 2013 to December 2016. The main objective of this research was to make ecological assessment on diversity, distribution, relative abundance, habitat association of small mammals and on their prevailing conservation challenges. Data on diversity, distribution, abundance, habitat association, pest status, possible conservation challenges of small mammals and their habitat were collected. A total of 40 grids from eight representative habitats were selected. A 5x5 Sherman Live trapping grid with 15 m spacing was employed for three consecutive days per each intensive grid. Overall, 230 mist net net-nights were employed during 60 nights. For chromosomal and molecular analysis tissue samples from each representative species were collected. For survey of local communities perception on small mammals conservation and pest status 370 households were selected. Sherman live traps, mist nets and mole rat traps were used to capture small mammals. Overall 36 species of small mammals were recorded of which at least 20 species or 55.56% were endemic to Ethiopia. Trap success ranged from 27% to 85.71% with overall trap success of 44.6%. Out of the 4302 captured individuals 4074 were rodents and 228 were shrews. In addition, 219 bats were captured of which 197 (89.95 were new captures, 16 (7.31%) were recaptures and the 6 (2.74%) were unidentified. The overall netting success and capture rate were 0.95 bats/net-night and 0.83 bats/net-h, respectively. The highest relative abundance was recorded for L. brevicaudus (21.36%) followed by S. griseicauda (17.50%) and S. albipes (16.44%). The least relative abundance was recorded for D. nikolausi and M. imberbis each having 0.03%. Capture per trap night was highest (55) for moorland habitat and least (16) in plantation habitat. Stenocephalemys griseicauda and L. brevicaudus were the most widely distributed species whereas C. fumosa, C. lucina, C. olivieri and M. imberbis were recorded from limited sites. More individuals of small mammals were captured during the wet season. The overall mean of reproductively active individuals was 38.17% and 20.02% and 18.15% during wet and dry seasons, respectively. The capture per trap night showed variations among the age of burnt Erica. Small mammals showed variation in distribution and abundance along altitudinal zonation. Results on chromosomal and molecular analysis of the representative species show similality with its previously described from different parts of the country and showed close affinity with the Bale Mountains. A total of 1993 individuals of ectoparasites that belonged to 24 taxa from examined 204 individuals of small mammals with the overall prevalence rate of 73.53% were recorded. All respondents perceived rodents as principal pests that cause great damage to their agricultural and household items. Overpopulation, uncontrolled hunting, poaching and deforestation, habitats destruction and degradation by agricultural expansion and settlement were perceived as major threats for the conservation of the area. Community based conservation strategies were supported by nearly all of respondents. As Chilalo-Galama Mountains Range had high diversity of fauna and flora, proper conservation measures have to be implemented.
An Ecological Study on Hamerkops (Scopus Umbretta) Along Lake Hawassa, Ethiopia
(Addis Ababa University, 2018-06-04) Asrat Zebib; Bekele Afework (Professor)
A study on population status, foraging nest building and breeding behaviour of hamerkops (Scopus umbretta) was carried out along the shore of Lake Hawassa, southern Ethiopia. Data were collected during the wet and dry seasons. Point count method was employed to estimate the population. Direct observation by the help of binoculars and necked eyes was used to record data on foraging, breeding and nest building. Data were analyzed using SPSS version 20 descriptive statistics and paired t test. The mean number of hamerkops in the study area was 168 during the wet season and 314 during the dry season. Hamerkops build huge nest and they spend most of their time in building their nest during the wet season. They breed during the late rain season and early dry season. Cultch size range from minimum three to maximum five. The mean clutch size was 4.3. The mean egg length and width was 45.9 and 34.0 mm, respectively. The mean weight was 27.1 g. Egg laying interval varied between 24 and 48 hours. Incubation started 24 hours after the laying of the first egg. Fledging time depended on the hatching period. Hamerkops feed on different food items at different sites, like fish, fish scraps, frogs and worms. Most of the time they feed on fish scraps during the dry season obtained from the fish market. They frequently feed worms at Fiker Hayiq during the wet season. The feeding pattern significantly differed based sites (p> 0.05) in the current study. Further detailed study should be carried out to get more exhaustive information on hamerkops.
Fish Diversity and Production in Tekeze Reservoir, Tekeze Basin, Ethiopia
(Addis Ababa University, 2020-11-15) Gebru, Shibabaw; Getahun, Abebe (Professor); Teferi, Mekonnen (PhD)
Ethiopia has several freshwater systems from where plenty of aquatic foods could be produced. However, due to poor management practices, the contribution of the fishery to the country’s economy is by far little. Tekeze Reservoir has potential in fish production, but little or no detailed and documented scientific information is available about the fish biology and fishing activities. Consequently, the fishery of the reservoir is poorly understood and its sustainability is unpredictable. Therefore, this study aimed to contribute to the management of the reservoir fishery by providing scientific information for sustainable utilization of the aquatic resources. Data was collected using various methods over a period of two years and analyzed using various statistical tools and methods. Fifteen fish species were identified in the present study. The index of relative importance (%IRI) of the key species in the reservoir includes Oreochromis niloticus, (35.5%), Bagrus docmak (22.6%), Labeobarbus intermedius (20.5%), Labeo niloticus (10.6%) and Labeo forskalii (10.2%). However, Clarias gariepinus, Labeobarbus nedgia, Raiamas senegalensis, Labeobarbus crassibarbis, Hetrobranchus longifilis, Garra dembeensis, Bagrus bajad, Labeobarbus bynni, Labeo cylindricus and Labeobarbus beso constitute below 1% of the total catch. The river mouth habitats contributed the most catch composition, while the pelagic habitats contributed the least. Length-weight relationship of O. niloticus, L. intermedius and B. docmak were best expressed by the equations TW = 0.014TL3.054 (r2 = 0.9743, P = 0.0001), TW = 0.0196SL2.9493 (r2 = 0.9609, P < 0.0001) and TW = 0.0098SL3.0819 (r2 = 0.9678, P < 0.0001), respectively. The overall mean condition factor was found to be 1.44±0.01 for O. niloticus, 1.88±0.02 for L. intermedius and 0.94±0.01 for B. docmak. The feeding habit of O. niloticus, L. intermedius and B. docmak indicated that both plant and animal origin food items were consumed by the species. However, phytoplankton for O. niloticus, detritus for L. intermedius, fish and fish remains for B. docmak were the most important food types. Although the proportion was different, the studied fish species consumed all food items in all seasons of the study period. In some size classes of O. niloticus and B. docmak, complete ontogenic shifts were observed, but all food items in different proportions were ingested by L. intermedius. The overall sex ratio (female: male) of O. niloticus and B. docmak was significantly deviated from the hypothetical distribution of 1:1(P iv < 0.001). However, the sex ratio of L. intermedius did not significantly deviated. Size (TL) at first maturity of O. niloticus was 24.2 cm for females and 24.87 cm for males. The size at maturity for L. intermedius and B. docmak (SL) were 20.84 and 27.42 cm for females and 22.05 and 26.79 cm for males, respectively. The mean absolute fecundity of the species was 1,513, 4,788 and 92,321 eggs for O. niloticus, L. intermedius and B. docmak, respectively. The studied species had extended spawning period, from July to October with peak spawning in August for O. niloticus and B. docmak and in September for L. intermedius. Labeobarbus intermedius preferred riverine habitats while O. niloticus and B. docmak prefer the littoral habitat for breeding. The catch per unit effort of the fishery ranged from 15.98 kg/boat/day to 3.26 kg/boat/day. The extent of immature fish harvesting by the commercial catch indicated that O. niloticus (33.32%), L. intermedius (37.72%) and B. docmak (42.17%) were caught before they attain their first sexual maturity. A total of 48 fishery associations with 3,174 members were distributed in the reservoir. The average age of the fishers was close to 30 and about 94% of them were males. The majority (67%) of the fishers were full-timers with the average fishing experience of 4 years and 64% of them had taken formal education. Gillnets and longlines were the commonly used fishing gears and operated for 24 hours in the reservoir. Addis Ababa and Mekelle were the major market destinations for filleted fish, but Shire and Humera towns were for the gutted and sun-dried fishes. The fishery contributed to the rural communities as source of nutrition and food security, employment opportunity and source of income. However, due to poor management practices, illegal fishing activities and overexploitation of the resources, the fish production and fishery business have declined. Therefore, to sustain the production and productivity as well as the socio-economic contribution of the reservoir fishery, the federal government and the two regional states such as Tigray and Amhara Regional States should take a responsibility to address the major problems that cause the depletion of the stock in the reservoir.
Fish Diversity, Abundance, Socioeconomic Importance and the Status of the Fisheries of Lake Hayq, South Wollo, Ethiopia
(Addis Ababa University, 2016-06) Seid, Zuriash; Getahun, Abebe(PhD)
This study was conducted on one of the northern high land fresh water lake; i.e., Lake Hayq, and its surrounding fishing community. The current fish diversity in Lake Hayq comprises of 4 species namely, Nile tilapia (Oreochromis niloticus), Catfish (Clarias gariepinus), Common carp (Cyprinus carpio) and Garra (Garra dembecha). However; Garra sp. has no economical value in the research area and hence it is not targeted & presented by fishermen. The fish species that is more abundant in the lake as a whole, around the lake shore and during dry (Begga) season is Nile tilapia, followed by common carp. Whereas, catfish is more abundant in the rainy season (Kiremt) in Lake Hayq. The species of tilapia and catfish are currently being depleted and not adequately captured. Instead, it is been identified that Carp (C, carpio), which has been introduced in to the lake in the recent years, reproduce very well and become dominated the lake. Sustainable fish resource in the lake provides animal protein and means of livelihood to surrounding community. However, it is found that the fish resource in the lake is facing biological and economical challenges. The current socio-economic importance of fish resources in the lake are stressed by demographic and economical pressures. Majority of the fishermen who were engaged in this fishing activities are young ranging from 21 to 30 years old. Individual fishermen daily fish catch exceed 100-200 immature tilapia per individual. Which estimated around 3513.6 quintal in a year. This indicated that in the current situation large number of tilapia (mostly preferred by surrounding community) harvested from Lake Hayq when we compared from past trends, but, low in quality (tilapia sp. become stunted). Due to this reason, individual fishermen monthly income did not exceed 1000 Et. Birr. Majority of them have no other income source for their livelihood and they are totally dependent on the lake’s resources. Members of Logo Hayq-Ardibo fishermen association, on the other hand, found relatively in a better position as a result of their catching effort from Lake Ardibo in addition to Lake Hayq. The problem is aggravated due to little employment diversification opportunity and lack of government support or poor accountability. The major anthropogenic activities that aggravate fish resource destruction are overfishing practices of individual fishermen using non recommended gillnet with mesh size less than 8 cm and continuous fishing even during reproductive seasons of some fishes (eg. Nile tilapia). Moreover, environmental pollution, destruction of fish reproductive sites & water level reduction, further degraded the habitats of the fishes. Generally the absence of effective lake management system accelerated the decline of the fish resources in Lake Hayq. To overcome these adverse impacts on the fish resource, there should be continuous professional follow up, diversification of employment for youth, organization of individual fishers into fishermen association. Moreover, introduction of other systems of producing tilapia species (like aquaculture) to restock the lake is recommended. Furthermore, there is a need for further study about the cause of stunting tilapia in this lake during recent years. Key words/phrases: Lake Hayq, diversity, abundance, socio-economic importance, lake management.
Habitat Use and Characterization of Young-of-the-Year (YOY) Labeobarbus Spp. in Gumara River, Lake Tana Sub-Basin, Ethiopia
(Addis Ababa University, 2020-01-01) Erarto, Felegush; Getahun, Abebe (Professor); Mengist, Minwyelet (PhD); Anteneh, Wassie (PhD)
Information regarding habitat requirements of different fish species at early life stages plays important roles for monitoring, protecting or managing fish populations and their habitats. Although spawning migration of Labeobarbus species to Gumara River has been reported by various studies, organized information on abundance, distribution, habitat use and preference of young-of-the-year were not available. Such information is very important for the management of the declining endemic Labeobarbus species of Lake Tana. So, the aim of this study was to investigate abundance, habitat use and characterization of young-of-the-year of the Labeobarbus species. Habitat use and characterization of young-of-the-year of the migratory riverine spawning Labeobarbus species of Lake Tana were studied in Gumara River and its tributaries from November 2018 to April 2019. Physico-chemical parameters were measured using probes and there were significant variation (p<0.05) among sampling sites. Fish sampling was conducted using point abundance sampling by electrofishing across banks and mid-channel to cover all habitat types. A total of 3,880 fish specimens were collected from all sampling sites. Out of the total catch, about 24.36% of the contributions were from young-of-the-year of the Labeobarbus species. The abundance of fishes varied between sampling months and sites and this might be attributed to the differences in physico-chemical parameters, substrate type, altitude, depth and velocity of the water. The Shannon’s index (H'=1.21) and evenness value (J'=0.53) in Gumara River indicate moderate pollution and uniform distribution of individuals. Among the six sampling sites, the highest (H' = 1.30) and lowest (H' =0.94) diversity index were recorded at sites in the upstream near to Wanzaye hot spring and below the bridge, respectively. In terms of mesohabitat, the species diversity and evenness were higher in riffle (H' = 1.25, J' = 0.57) than run (H' = 1.15, J' = 0.55) and the pool (H' = 1.11, J' = 0.50). The result showed that the species prefer at a mesohabitat scale riffles and later pools in Gumara River and this is mainly due to the drying of riffle habitats during the dry season and hence forced to shift to pool habitats. At a microhabitat scale also juveniles prefer sites with moderate water depth, low to medium water velocity; gravel substrate type and vegetation cover. Pool habitat served as the only option until the next rainfall comes. Therefore, emphasis should be given to the factors which may lead to the collapse of the pool habitats, especially water abstraction through pumping for small scale irrigation. The detailed study on the habitat modeling and the habitat suitability index should be done for proper management of the Lake Tana fishery.
Population Status, Behavioural Ecology of Plains Zebra (Equus Quagga) and Human-Wildlife Conflict in Nechisar National Park, Ethiopia
(Addis Ababa University, 2021-01-16) Fekadu, Addishiwot; Bekele, Afework (Professor)
Plains zebra is the most abundant equid in the world. In Ethiopia, the total population size of this species was estimated to be around 2000 individuals. Nechisar National Park holds the largest populations of Plains zebra.The present investigation deals with population status, habitat preference, diurnal activity, feeding habit of Plains zebra (Equus quagga) and human-wild life conflict in Nechisar National Park. Data were collected for two consecutive years including both wet and dry seasons between December, 2017 and April, 2019. The entire study area was divided into five major habitat types. A total of 28 line-transects on five major habitats such as open grassland (7), wooded grassland (6), bushland (7), riverine vegetation (4) and lakeshores (4) were determined. Based on the observability of the animals 700 to 1000 m strip width was considered and fixed. Adjacent transects were at least 1.5-2.0 km apart. The average length of the line-transect was 9.84 km. Counting was carried out through direct observations with naked eye and/or by using binoculars. Diurnal activity pattern of plains zebra was also carried out through direct observations on major activity pattern using a 5 minutes focal animal sampling period. Feeding habit determination was carried out through direct focal animal observation. Semi-structured interviews and focus group discussions were also held with the local people. Data were analyzed using population density estimation parameters. A total of 716 individuals of Plains zebra were recorded from the study area. On average 272.25 (38.0%) and 443.75 (62.0%) were recorded during the dry and wet seasons, respectively. The distribution and abundance of the animals varied among habitats and between seasons. Plains zebra showed high preference for grassland followed by wooded grassland and bushland. The record showed maximum diurnal activity pattern for grazing (56.5%) and minimum for grooming (6.6%). From observations of foraging activities, six grass, four herbs and three shrubs species were identified as their common food items. During both seasons, Plains zebra preferred grasses species to others and didn‟t show significant difference (F(5,10)=5.865, P>0.05). Herbs and shrubs were consumed more during the dry season than the wet season. They showed statistically significant variation in the consumption of Herbs (F(3,6)=44.38, P<0.05) and Shrubs (F(2,4)=19.42, P<0.05). On average, they proportionally consumed grass (70.0%), herb leaves (19.7%) and shrubs (10.3%). A total of seven species (five herbivores and two omnivores) were recoded as major hazards of crop damage, whereas seven species (six carnivores and one omnivore) were recoded as major predators. Crop damage, livestock loss and human impact such as overgrazing, illegal settlement, and resource exploitation were the major problems (60.2%) encountered between human and wildlife in the study area. Relatively, 51% of the respondents had a negative attitude towards conservation areas and wildlife. Responsible bodies and concerned stakeholders should integrate to resolve the challenges of conservation threats and protection of the wildlife in the study area.
Species Composition and Abundance of Mosquitoes in Selected Areas of Gobu Sayo District, West Oromia, Ethiopia.
(Addis Ababa University, 2018-09-09) Dugasa, Mekonnen; Dugassa, Sisay (PhD)
Prior to implementing vector control, it is always important to have baseline information about the species present and their densities. This study was conducted in selected areas of Gobu Sayo district East Wollega Zone, West Oromia, Ethiopia between September and August; 2018. It was intended to identify mosquito species present and estimate their abundance. Hand collection, spray sheet collection and hand net collection methods were used. It was investigated that Anopheles; Culex and Aedes mosquitoes are widely found in the study areas. The mosquitoes belong to Family Culicidae ;- ( subfamily anophelinae and culicinae). Those mosquitoes were morphologically identified by using identification key under compound microscope based on their morphological characteristics. Anopheles were 600, the most predominant in all the selected areas. The second most abundant was culicine mosquitoes 260 followed by Aedes 40. Generally, 900 individual adult mosquitoes were sampled from the three kebeles. The main rainy season usually extends from June to August and short rainy season occurs in March to May. The mosquitoes appear abundantly following the short rainy season (March to May) and the main rainy season (September to December). The principal malaria vectors, female Anopheles mosquitoes are abundant in the district.
Species composition, Abundance and Activity Pattern of Birds of Addis Ababa Abattoirs Enterprise
(Addis Ababa University, 2007-04) Hibste Hiwot; Bekele Afework (Professor)
Studies on species composition and abundance of birds in Addis Ababa Abattoirs Enterprise were carried out from March 2006 to February 2007. The presence of food, scraps and offal, increased the species richness and abundance of birds in the area. In addition to the abundant supply of food, the availability of resting and perching structures has made Addis Ababa Abattoirs Enterprise a favorable area for different species of birds. Point count method was employed to record the relative abundance of individual bird species. The piles of bones although has unpleasant odors, it is a marvelous place for viewing vultures as well as wetland birds. The site supports 21 species of birds, including the endemic species – Wattled Ibis, White-collared Pigeon and Thick-billed Raven. The species composition decreases during wet season due to the departure of migratory birds. From the total species recorded, 57.14% were regular. The most abundant species were Hooded and African White-backed Vultures. The Vultures were usually observed flying over the study area, roosting on the roof of the slaughter house, and also on the ground either being around of feeding. Feeding activity was from 06: 00 – 18:00 h during the dry season. The fresh dumping site is intensively disturbed by human activities and thus affected the normal feeding time of birds. The urbanization level of the area affected bird community in depriving roosting trees. Most of the vultures were observed coming from southwest direction of the study area. Key words: abundance, composition, dumping site, perching, raptors, roosting, scraps, urbanization
Species Diversity and Abundance of birds of Addis Ababa bole International Airport
(Addis Ababa University, 2011-07) Dessalegn Tsigereda; Bekele Afework (Professor)
Ecological investigation of species diversity and abundance of birds was conducted from August 2010 to March 2011 in Addis Ababa Bole International Airport. Transect count and point count methods were used to investigate the abundance of birds. Observation was conducted by periodically walking along the study area early in the morning and late in the afternoon. Different diversity indices and statistical methods (Chi-square test and correlation) were used to analyze data collected during the field survey. Movement patterns, seasonal and temporal bird distribution as well as birds strike records were investigated. A total of 74 bird species grouped under 13 orders and 31 families were recorded. August had the lowest species diversity (H’=3.71), species evenness (E=0.61) and species richness (41). The highest species diversity, evenness and richness were recorded in December (H’=4.06), January (E=0.74) and September (61), respectively. Variation in abundance of birds was statistically significant between seasons and months. Abundance score of uncommon bird species was high both during the wet and dry seasons using encounter rate. Appropriate management of bird attractant sites is very important to discourage birds from the airport. Key words: Abundance, bird strike, management, species diversity
Studies on Insect Diversity and Abundance at Belette-Gera Forest, South Western Ethiopia
(Addis Ababa University, 2016-05) Beyene, Belay; Getu, Emana(PhD)
Belette-Gera Forest is one of the Afromontane rain forests in south western Ethiopia. The diversity and abundance of insect communities within the forest are not studied and there is no documentation of the insect fauna of the forest.Iinsects is ecologically important and play valuable role in the ecosystem of Belette-Gera forest. This study identified insect species within the forest and assesssed thier diversity, abundance and distribution among habitats and seasons. Habitat distribution of insect fauna was catagorized into three habitats having different land uses/cover and varying degrees of disturbance; Natural forest habiat, Plantation forest habitat and Wetland habitat. Seasonal distribution of insect fauna was also studied in three seasons; long rain season, long dry season and short rain season. Insect species richness and abundance of insect communities of Belette-Gera forest was investigated along a line transect of 100m × 100m starting from the bottom of the valley to the top of the ridge with sample quadrats of 10m ×10m laid for sampling insects. A total of 1560 insect specimens from 14 orders and 120 families were collected from September 2013 to August 2015 using sweep net trap, beating cloth, pitfall trap and hand picking. Shannon-Wiener diversity index and Evenness were used to measure diversity and abundance of the insects at the family level. The highest insect diversity was observed in the order Coleoptera with Shannon diversity index, Hʹ value of 1.77 and evenness, E value of 0.37. Dermaptera, Ephemeroptera, Mecoptera and Neuroptera were the raret insect orders. Similarly, diversity was measured in each habitat III using Shannon-Wiener species diversity index and Evenness. A total of 620 specimens (39.74 %) in the Natural forest habitat, 472 specimens (30.26 %) in the Wetland habitat and 468 specimens (30 %) in the Plantation forest habitat, were collected. These insects were used to determine the richness of the insect fauna in each habitat type. The highest insect diversity was observed in the Natural forest habitat with (Shannon’s, Hʹ= 2.36) and (Evenness, E = 0.49) followed by Plantation forest habitat (Hʹ= 1.84; E = 0.38) and the lowest were recorded in the Wetland habitat (Hʹ= 1.78; E= 0.37). In addition, the influence of season on the diversity and abundance of insects was computed for two different years (2013/2014 and 2014/2015). Shannon-Wiener species diversity index (H’) and Evenness (E ) were used to measure species diversity and abundance in each season. Paired sample T test was computed to determine the significant differences in insects collected in the rainy and dry seasons. Insect abundance and diversity were significantly different between seasons and in 2013/2014 the highest diversity was recorded in the long rain season with (Hʹvalue of 2.563; E value of 0.563). On the other hand, the lowest diversity was recorded during the short rain season (Hʹ value of 1.234; E value of 0.271). Furthermore, in 2014/2015 the highest diversity was recorded in long rainy season with Shannon’s Hʹvalue of 1.868 and with E value of 0.417. The lowest insect diversity was recorded from short rainy season with Shannon’s Hʹ value 1.57. The diversity and abundance of insect communities varied with respect to habitat type and season. As a result, Wet land habitat, Plantation forest habitat and Natural forest habitat were varied in increasing order with respect to diversity and abundance of insect communities. In addition, Short rainy season, Long dry season and Long rainy season varied in increasing order with respect to of diversity and abundance in the study forest. The variation of insect species diversity and abundance in the habitat types and seasons were the result of IV environmental variation (both biotic and abiotic factors), human interference; and the responce of insects to thesef actors influenced the diversity and abumdance of insect communities residing in these habitats in different seasons. Therefore, knowledge on the identity of insect species and factors which influence their diversity and abundance is important as baseline information for further study to assess the different aspects of the insect founa adapted in Belette-Gera forest. Key words: Diversity, abundance, insects, habitat, season
Studies on the Status of Chilo Partellus (Swinhoe) (Lepidoptera: Crambidae) and its Natural Enemies, and the Effect of Botanicals and Cow Urine Against the Pest and Natural Enemies
(Addis Ababa University, 2019-05-20) Nega, Adem; Getu, Emana (Professor)
The exotic stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) is the most important pest of sorghum in East Africa. The insect infests sorghum crop throughout its growth stages. It has also been recorded and documented from wild host plants. C. partellus has several native and exotic natural enemies. Field and laboratory studies were conducted to know the status of C. partellus and its natural enemies and assess the efficacy of botanicals and cow urine against C. partellus and their effect on the natural enemies. Surveys were conducted in 2016/17 and 2017/18 in three districts and nine farmer fields of Kalu, Bati and Dawa Chefa districts, Ethiopia. Sampling was done both randomly and purposively. Analysis of variance (ANOVA) was carried out to determine if there were any significant differences across the locations and between the plant growth stages. Laboratory evalution of plant and animal-based insecticides and optimum concentration on C. partellus was conducted in 2016. The experiment was laid out in completely randomized design in three replications for each rate. The rates were 2g, 2.5g, 3g of powder and 1ml, 1.5ml and 2ml w/v of the solutions. The most effective biopesticides were further tested in 2017 in farmer’s field. The trial was designed in a randomized complete block design in factorial arangment in three replications. The treatments were at two levels of frequencies (2 & 3 times application) and three rates of powder (1g, 2g and 3g) and three rates of solution (5%, 10% and 15%). The study revealed that C. partellus constituted 90.3 & 91.2% on sorghum and 45.4 & 69.2% on wild hosts in 2016/17 and 2017/18, respectively. Significant differences were observed among the host plants and sorghum growth stages. In sorghum, C. partellus density were found to be significantly higher than on wild hosts (P<0.05). Relatively higher numbers of larvae (5.02±0.5) per plant were recorded from Bati at seedling stage and the lowest; (3.32±0.3) was from Kalu. Significant difference was observed in incidence of C. partellus (F=11.8; d.f.=2;P<0.008). C. partellus was significantly (F=60.3;d.f.=2; P<0.000) different at the three plant growth stages across the locations. Similarly, significant (F=24.75; d.f.=2;P<0.001) difference was recorded at vegetative stage in terms of exit holes. Natural enemies’ abundance showed significant difference among sorghum growth stages. C. flavipes (Cameron) recorded abundantly at maturity stages of sorghum. The highest number (0.48) was recorded from Bati at the vi maturity stage with the relative abundance of 33.8%. Cotesia flavipes parasitism varied across the locations and host growth stages. The highest (61.5%) parasitism was recorded from Bati at maturity in both seasons. Ants were highly abundant at maturity and lower at early stages at Bati, while (83.7%) relative abundance was recorded from Kalu. Earwigs were highly abundant in Dawa Chefa district, while the maximum number was found from Bati at maturity stage with the relative abundance of 26.3%. Laboratory study showed that Millettia ferruginea seed powder and aqua extract caused 100% mortality at the highest rates after 24 hrs exposure. Cow urine, Phytolacca dodecandra aqua extract and its mixture with cow urine were found effective. Results of field trial showed that all pesticides formulations significantly (P<0.01) reduced C. partellus damage at the highest rates with two times applications compared to untreated check. Likewise, their effect on the main natural enemy of C. partellus was minimal. C. partellus was found attacking by several natural enemies at each stages of sorghum, thus it is suggested that use of plant and animal-based insecticide can be regarded as suitable alternative to synthetic insecticides for the management of C. partellus in the field.
Wildlife Density, Distribution and Abundance With Emphasis on Cheetah Prey in Machakos and Makueni Districts, Kenya
(Addis Ababa University, 2008-06) Musya Cosmas; Bekele Afework (Professor)
More than half of Kenya’s wildlife is found outside protected areas. However, its continued existence in these areas is threatened by changes in land-use patterns. The present study investigated wildlife density, distribution, abundance, and factors influencing settlements in ranches that have been partially sub-divided, completely subdivided and the ones that have not undergone any sub-division in Machakos and Makueni districts, Kenya. Data on density and abundance by day and night was collected over a six month period in two seasons by means of transect counts, covering a distance of 1182 kilometers and analysed using DISTANCE software programme. Data on settlements was obtained by digitizing survey plans for four farms in ArcView 3.2 programme revealing 5456 smallholder plots of land ranging from 2 to 30 acres. Distribution of wildlife species was also obtained by means of the same programme. In total, 32 wild animal species were recorded in the study area, out of which eight were categorised as preferred cheetah prey. The results show that settlements in the subdivided parts of the study area are influenced by the availability of water and transport infrastructure. Wildlife density was lowest in the partially sub-divided ranches and highest in the unsubdivided ones. Although density varied significantly between day and night, there was no seasonal variation. The total sub-division of two ranches and continued settlements will have an effect on the wildlife as farming and settlement take place. It is suggested that monitoring of wildlife and settlement patterns be continued and strategies developed to encourage wildlife conservation. Key words: Abundance, conservation, density, protected area, seasonal variation, settlements, wildlife.

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