Effect of Environmental Stressors on the Distribution and Abundance of Macroinvertebrates in Upper Awash River at Chilimo Forest, West Shewa, Ethiopia

Ethiopia is experiencing deterioration in river quality resulting in adverse effects on human health and hydrobionts. This study aimed to analyse the effects of specific environmental stressors on the distribution and abundance of macroinvertebrates in the Upper Awash River. The study was conducted from January 2018 to March 2018. Macroinvertebrates were collected from five sites using standard handheld nets. Physicochemical parameters including electrical conductivity, dissolved oxygen, total phosphorous, nitrate-nitrogen, pH, dissolved oxygen and water temperature that can affect the distribution and abundance of macroinvertebrates were assessed. A total of 14,465 individuals belonging to 33 families of insects and 5 families of the noninsect group were identified. Among all recorded taxa, Diptera was the most abundant and diversified order. Macroinvertebrates among the five sites showed variation in species evenness, richness, and Shannon Diversity Index. Values obtained from biotic indices and environmental parameters indicated the presence of organic pollution at different levels. The impacted downstream site paper mill waste (Walgata) had the relatively highest H-FBI index followed by Osole (more agricultural activities) indicating that Walgata and Osole were poorer in benthic faunal diversity than other sites. In addition, as habitat and water quality degradation increased, the number and percentage of Plecoptera, Ephemeroptera, and Trichoptera (EPT) decreased. The selected metrics will be also useful for the monitoring and assessment of the riverine systems and to access the impact of different stressors. As perturbation increased, species diversity, ETHbios index, Average Score Per Taxon, and family richness decreased, while the percentage of Chironomidae, Diptera, Dominant Taxa, and Hilsenhoff Family-Level Biotic Index increased indicating that tolerant species become abundant in degraded river bodies. Environmental protection agencies of governmental and nongovernmental organizations should make awareness for the local people so that they reduce activities that affect the river. Paper factory should also monitor its effluent from directly discharging into the Upper Awash River.

The Biology of the African Bonytongue Heterotis niloticus (Cuvier, 1829) from the Lower Niger River at Agenebode in Edo State, Nigeria

Background. The African bonytongue, Heterotis niloticus, is readily accommodated in the fresh water of the Niger River. It is available all year round with a large population of juveniles and adults due to its fast growth and versatile feeding habits. This commercial fish is a highly preferred source of food because of its high protein content and hardy flesh, thus forming a very important component in the diet of many Nigerians. It is highly valued because of its socioeconomic importance and benefits. Hence, this research is designed with the aim of studying the biology of the African bonytongue, Heterotis niloticus, and providing viable information about its importance in fish culture in order to make an available added variety of culturable and affordable fish species in Nigeria. Results. The oesophagus is a muscular organ that is short and distensible. The oesophagus leads to the gizzard-like stomach, a reddish bilobed organ that is muscular and tough. H. niloticus is an omnivorous macrophage detritor, consuming a wide variety of bottom-dwelling food items. The histology of the gastrointestinal tract reveals four conspicuous layers from the inside to the outside: mucosa, submucosa, inner circular layer and outer longitudinal layer of muscularis, and serosa. The presence of numerous mucus glands and longitudinal folds with a prominent columnar epithelium provides durable length or an extension of the gut mucus to aid lubrication and easy passage of food materials, protecting the mucosal epithelium from mechanical or chemical injuries arising from interactions with digestive tract contents or enzymes. In addition, the presence of absorptive cells helps in the absorption of valuable nutritive substances. Conclusions. The anatomy of the mouth and gut and the aforementioned histology are modified to accommodate the feeding habits. H. niloticus has a single ovary that rests on the right side of the fish; it is reproductively active as the flood plains rise and peaks at the peak of the rains, being a moderately fecund fish. The high fecundity is complemented with peaks of GSI observed during the months of September, October, and November, which reveals spawning periods. Hence, the aforementioned attributes of H. niloticus make the fish a viable fish species for culture.

Latitudinal Variation into the Macrofaunal Assemblages Associated to Zostera noltei Seagrass along the Atlantic Coast of Morocco

Large-scale research on seagrass-associated benthic fauna is very important for future regional marine conservation. In our study, we investigated spatial and latitudinal variation of benthic macroinvertebrate assemblages associated to Zostera noltei Hornemann, 1832 beds from five semi-enclosed coastal systems (SECSs) ranging from 23°N to 34°N along the Atlantic coast of Morocco. Overall, 17,320 individuals were reported as belonging to 96 taxa. The ecological community descriptors differ significantly at the level of the site. Specific richness showed an inconsistent significant pattern with latitude. The multivariate analyses of the assemblage’s composition showed 57% of total variation observed in benthic assemblages, while the PERMANOVA analysis confirmed that this variation is significant at the level of the site. According to DistLM results, variations in belowground biomass, and percentage of mud, were the important predictor variables explaining this variation along the large scale of the studied SECS. However, such patterns could be related to other factors such as habitat heterogeneity and regional, biogeographic, and anthropogenic factors. The present study marked the first attempt on broad-scale ecological research of seagrass beds in Morocco and offers baseline data for planning the broad-scale conservation of biodiversity in seagrass beds that remain suffering from multiple human-induced threats such as coastal developments and climate change.

Diversity and Some Biological Aspects of Fishes in Lake Maybahr, Albuko Woreda, Ethiopia

Because fishes live in less-accessible habitats, their remarkable diversity is rarely appreciated. The fishery sector is growing rapidly worldwide with the intention of improving the livelihood in developing nations. Therefore, conservation and management of aquatic resources become eminent. Morphometric measurements of fishes are important tools in fish biology and fisheries assessment and conservation. Ethiopia is one of the developing countries with rich water resources. Although there are plenty of water bodies in the country, they are less explored for their ichthyofaunal documentation. Therefore, this study aimed to explore the diversity and some biological aspects of fishes in Lake Maybahr. The fish sample was collected from selected sampling sites using gill nets with varying mesh sizes. Fish identification was done in the field using relevant taxonomic keys. After identification, the total length (TL) and total weight (TW) of the specimens were measured to the nearest 0.1 cm and 0.1 g, respectively. After measurement, the samples were labeled and preserved in a 10% formalin solution. Two fish species were documented in the study area. The length-weight relationships indicated that both species (C. carpio and O. niloticus) exhibited allometric growth during the wet season. But C. carpio demonstrated an isometric growth in the dry season. The diversity index (H’ = 0.69) revealed that fish diversity in the current study is far less than the result reported in the other studies. The evenness index (J’ = 0.99) showed that each species is fairly represented by a number of individuals. The correlation coefficient value of length and weight parameters is statistically significant at a 1% significance level (s, R2 = 0.85). The mean FCF revealed that both fish species are in good health. Further study on local people’s perception, initiating fishing activities, and organizing and providing training to youth is recommended.

Species Composition, Diversity, and Habitat Association of Medium- and Large-Sized Mammals in Chimit-Kolla, Abay Gorge, Ethiopia

Identifying the species distribution, diversity, and habitat association provides input to launch proper conservation interventions. A survey of medium- and large-sized mammal species was conducted in Chimit-Kolla area to assess their distribution, diversity, and relative abundance in November 2019 to September 2020. Line transect sampling and focus group discussions were used for data collection. Shannon diversity index and Sorenson’s coefficient were used to compute the diversity and habitat utilization of species. The association of species among habitats was tested using the chi-squared test. In the survey, 18 species of medium- and large-sized mammals belonging to the order Artiodactyla (7 species), Carnivora (6 species), Rodentia (1 species), Primates (3 species) and Tubulidentata (1 species) were recorded. The association of mammalian species among the three habitats was not significant ( p > 0.05 ). However, the abundance of mammal species was significantly associated with forest habitats ( p < 0.05 ). There was a significant variation in abundance of medium- and large-sized mammal species observed in the dry season (157, 57.5%) as compared to the wet season (116, 42.5%) (χ2 = 6.17, df = 1, and p = 0.013 ). The most abundant species was olive baboon (Papio anubis), followed by grivet monkey (Chlorocebus aethiops) and crested porcupine (Hystrix cristata). While leopard (Panthera pardus), white-tailed mongoose (Ichneumia albicauda), and aardvark (Orycteropus afer) were the rarest mammalian species recorded. Forest habitat has the highest species diversity (H’ = 2.276) than riverine vegetation and wooded grassland. Mammal species showed a considerable similarity among habitats, and the highest similarity was recorded between forest and wooded grassland (S = 0.8). The study area relatively has considerable numbers of medium- and large-sized mammal species, and urgent conservation action is required to reduce the emerging threats (hunting, charcoal production, agriculture, and investment expansion) and ensure survival of mammal species.

Contact Toxicity Effects of Selected Organic Leaf Extracts of Tithonia diversifolia (Hemsl.) A. Gray and Vernonia lasiopus (O. Hoffman) against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

Maize weevil (Sitophilus zeamais) infestation results in a substantial reduction in the quantity and deterioration of the quality of stored maize. Most farmers control weevils using conventional pesticides which are usually associated with several human health risks as well as intoxication of the fauna and flora. However, bioinsecticides form an alternative intervention since they possess fewer side effects on human health, are ecofriendly, and are readily available. This study sought to validate and document, in a systematic way, the pesticidal properties of the species Tithonia diversifolia and Vernonia lasiopus used for many years by many people of the world on S. zeamais. The plant leaf samples were obtained from Embu County, Kenya. Dichloromethane and ethyl acetate solvents were used to extract active phytochemicals from the dried plant sample powder. The GC-MS analysis of the obtained extracts was performed at ICIPE laboratories to identify their phytochemical compositions. Twenty grams of maize grains were put in 50 ml plastic vials and admixed with different treatments. The positive control group was treated with Actellic Super™, while the negative control was treated with the respective extracting solvent only. The experimental groups were separately treated with the plant leaf extracts at doses of 25, 50, 75, and 100%. After treatment, each of the six groups was infested with 10 male S. zeamais and weevil mortality as a result of contact toxicity of the treatments was assessed at 6, 24, 48, 72, and 96 hours after the insects were exposed to the extracts. Results of the study indicate that the selected organic leaf extracts of T. diversifolia and V. lasiopus possessed significant contact insecticidal effects that ranged between 1.67 to 99.98%. Furthermore, the GC-MS analysis revealed several active biocompounds in T. diversifolia and V. lasiopus extracts, which are known for their considerable insecticidal effects. Our data suggest that the organic leaf extracts of T. diversifolia and V. lasiopus have considerable insecticidal properties and would, therefore, be a valuable bioprotective agent for stored maize grains against S. zeamais.

Przewalski’s Horses (Equus ferus przewalskii) Responses to Unmanned Aerial Vehicles Flights under Semireserve Conditions: Conservation Implication

Recent technological innovations have led to an upsurge in the availability of unmanned aerial vehicles (also known as drones and hereafter referred to as UAVs)—aircraft remotely operated from the ground—which are increasingly popular tools for ecological research, and the question of this study concerns the extent to which wildlife responses might allow aerial wildlife monitoring (AWM) by UAVs. Our experiment tests the hypothesis that the wildlife-UAVs interaction depends strongly on flight altitude that there may be a lowest altitude range for which the ungulates are not exceedingly disturbed, dictating a practically achievable level of discernibility in flight observation, for this question might influence the future viability of the UAVs in the study and protection of the other wildlife in China’s semiarid ecosystem. We examined the behavioral responses of a group of enclosed Przewalski’s horses (Equus ferus przewalskii) to the presence of different in-flight UAVs models by conducting flights at altitudes ranging from 1 to 52 meters and recorded the heights at which each horse reacted to (noticed and fled) the UAVs. All horses exhibited a stress response to UAVs flights as evidenced by running away. The results suggest strong correlations between flight altitude and response across the different subjects that adults generally noticed the UAVs at the larger heights (20.58 ± 10.46 m) than the immature (4.67 ± 0.87 m). Meanwhile, reaction heights of females (15.85 ± 6.01 m) are smaller than that of males (26.85 ± 18.52 m). Supported by their biological roles in herds (e.g., males must give protection to his entire herd while females are purely responsible for their offspring), our results also show that age, closely followed by gender, are the two most significant elements that determine a horse’s level of alertness to the UAVs. This research will help future scientists to better gauge the appropriate height to use a drone for animal observation in order to minimize disturbance and best preserve their natural behavior.

Breeding Performances of the European Blackbird (Turdus merula) in Morocco: Habitat Selection, Breeding Phenology, and Breeding Success

The European Blackbird (Turdus merula) is a widespread species. In Morocco, available knowledge on this species is limited to a few descriptive pieces of information with no detailed data provided. With climate change and the intensification of agricultural activities, the study of the breeding performances of this species is indispensable for management purposes. This study investigates breeding biology, nesting habitats, breeding chronology, and reproductive success of the European Blackbird in both apple orchards and surrounding woody vegetation at Ait Ayach (Morocco) between March and August 2016. We monitored weekly nest status, nesting sites, breeding dates, and failure factors. Results showed that the European Blackbird nests mainly in apple orchards, on Golden Delicious and Starkrimson Delicious trees. Nest height above the ground was 214.15 ± 0.09 cm. Blackbird nests were cup-shaped with medium size dimensions and built from twigs, including dry leaves, stems, and roots walled by the mud. Breeding activities started firstly by nest construction during the last week of April, secondly by egg laying during the first week of May, and thirdly by hatching during the second week of May. Among the 74 surveyed nests, 100% were active during the nesting phase and 88.38% of eggs have succeeded during the incubation phase. In total, 69.03% of chicks have been emancipated. In short, 15.9% of clutches were attacked by predators, 14.35% of clutches were failed due to nest desertion, and 8.75% of chicks were dead. Our study provides the first and only detailed data on reproductive parameters of the European Blackbird in Moroccan ecosystems. Data collected from this study provide valuable information for long-term monitoring of the Moroccan Blackbird population. Additionally, our data offer a possibility of large-scale comparative studies of the reproductive ecology of the Blackbird species.

Species Composition, Relative Abundance, and Habitat Association of Avifauna in Zegie Peninsula Forest Patches and Associated Wetlands, Bahir Dar, Ethiopia

Introduction. Ethiopia is one of the most avifauna rich countries in Africa. Avifaunal surveys are required to inform conservation decisions and enhance land management for biodiversity. Avifaunal surveys from Ethiopia are lacking. This study examines species composition, relative abundance, and habitat association of avian fauna in Zegie Peninsula forest patches and associated wetlands from surveys carried out from August 2018 to March 2019, covering both the wet and dry seasons. Data Collection. Forest, shrub, lakeshore, and wetland habitats were identified as ecologically relevant habitats in the study area for data collection. Data were collected using point count and line transect methods, for 24 days in total for both seasons in the morning and afternoon. Results. A total of 96 species of birds were identified during the whole study period. Out of the total, 40 species were observed during the wet season, 13 during dry and 43 species in both seasons. There was significant variation of species distribution among habitats. During the wet season, the highest species diversity was recorded in the wetland habitat followed by forest habitat. During the dry season, avian diversity was the highest in the lakeshore followed by wetlands. The highest evenness was observed in the shrubland during both the wet and dry seasons. During the wet season, the highest species similarity was recorded between wetland and lakeshore habitats, and during the dry season, the highest species similarity was recorded between forest and shrub habitats. Based on encounter rate data, 64 (66.66%) of the avian species were uncommon. Conclusions. Compared to previous studies conducted in the study area, species diversity was lower. This might be due to various anthropogenic activities such as deforestation of trees for timber and cutting trees for firewood. Therefore, awareness creation should be given to the local community to reduce habitat destruction due to various human-induced factors.

Culex (Diptera: Culicidae) Mosquitoes in Jazan Region, Saudi Arabia, and Their Molecular Identification

Morphological characteristics have been the gold standard method to identify mosquito species. However, morphological identification has many limitations including lack of expertise and damaging of external characters due to improper specimen handling. Therefore, we used the polymerase chain reaction technique (PCR) as an integrated tool to identify Culex mosquito species to establish a more precise and reliable identification system related to their spatial distribution in Jazan region. We identified Culex mosquito species and subspecies using taxonomic keys, and then we used the polymerase chain reaction technique (PCR) as an integrated tool to confirm and refine the list of Culex mosquito species in the region. Phylogenetic trees were constructed for the identified species, and their distinctive clustering was compared with their reference’s species in the GenBank. We identified 7026 adult Culex mosquitoes belonging to 4 species. Culex tritaeniorhynchus was the predominant species (45%), followed by Cx. quinquefasciatus (32%), then Culex sitiens (20%), and Cx. pipiens (3%). The most infested areas by Culex in the region were Gizan and Sabya. The PCR achieved 100% success in identifying the four Culex mosquito species. We also report the molecular identification of Cx. quinquefasciatus and Cx. pipiens species for the first time in Jazan region while the molecular identification of Cx. tritaeniorhynchus and Cx. sitiens was reported for the first time in Jazan region and the whole Saudi Arabia. This study utilized for the first time PCR to identify Culex mosquito species in Jazan region. The PCR is a complementary and integrated taxonomy-based identification tool for mosquito species. This integration has the capacity to promote and enhance vector surveillance and control programs, as well as defining the genetic diversity of species in the region.