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Diet breadth variation and trophic plasticity behavior of the African bonytongue <i>Heterotis niloticus</i>(Cuvier, 1829) in the SôRiver-Lake Hlan aquatic system (Benin, West Africa): Implications for species conservation and aquaculture development

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Natural Science 2013年第12期5卷 1219-1229页

作者： Alphonse Adite Adam Gbankoto Ibrahim Imorou Toko Emile Didier Fiogbe Département de Physiologie Animale Laboratoire de Pharmacologie Faculté des Sciences et Techniques Université d’Abomey- Calavi Cotonou Bénin Faculté d’Agronomie Université de Parakou (UNIPAR) Parakou Bénin PRECOB Unité de Recherches sur les Zones Humides Département de Zoologie Faculté des Sciences et Techniques Université d’Abomey-Calavi Cotonou Bénin

The African bonytongue, Heterotis niloticus (Pisces: Osteoglossidae), is an omnivore foraging mainly on aquatic insects, microcrustacea, seeds and detritus. We examined the diet breadth and the trophic plasticity behavior of this species (1461 specimens) in the S? River and Lake Hlan water system located in the southern Benin (West Africa). Overall, the mean diet breadths of the two populations of Heterotis from both habitats were not significantly (p ≥ 0.05) different and were not associated with seasons. However, in Lake Hlan, mean diet breadths tended to increase with size (r = 0.81) and gut length (r = 0.82) indicating that bonytongues ingest a broader range of food resources as they grow. In both habitats, the positive correlation of both standard length (Log SL) and gut length (Log GL) with the volumetric proportions of detritus and with the volumetric proportions of seeds suggests that the consumption of these two food resources increased with the size of Heterotis and with the development of the digestive tract. Likewise, the negative correlation of both (Log SL) and (Log GL) with the volumetric proportions of aquatic insects and with the volumetric proportions of microcrustacea suggests that the consumption of these two food categories decreased as the size and the gut length of Heterotis increased. The differences in the consumption of microcrustacea (13.77% in Lake Hlan versus 2.63% in S? River) and mollusks (0.73% in Lake Hlan versus 4.91% in S? River) evidenced that Heterotis shifts his trophic structure according to resource availlability in the habitat. This foraging behavior suggests a degree of trophic plasticity in Heterotis. The specialized morphological structure of Heterotis, mainly the presence of a relatively high number of gill rakers (42 - 94 rakers on the first branchial arch) during its whole life, allowing sieving of zooplankton and other microcrustacea, and the presence of the gizzard favored this trophic plasticity. The broader diet bre

关键词： African Bonytongues Aquaculture Conservation Diet Breadth foraging Behavior Gill Raker Omnivore Trophic Plasticity

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Variations in Patch Use by Ruminant and Non-ruminant Herbivores in a Tropical Wildlife Reserve, Ghana

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Journal of Resources and Ecology 2022年第6期13卷 1143-1151页

作者： Godfred BEMPAH Joseph KAFRIFA Moses ANARTEY LU Changhu College of Forestry Nanjing Forestry UniversityNanjing 210037China Department of Conservation Biology and Entomology University of Cape CoastCape Coast CC-145-8669Ghana Department of Animal Science University of Energy and Natural ResourcesSunyani BS-0061-2164Ghana College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037China

Food processing and consumption by herbivores are affected differently by the availability of forage quality and quantity per unit of time. This demonstrates the “Allometric response concept”, and it is considered a significant determinant in habitat use for foraging by grazers. The relevance of this approach has comprehensively been applied to herbivores of different body sizes, but little is known about its demonstration to explain patch use in herbivores with different digestive physiology and body size. We explain the use of patches by grazing herbivores of different digestive physiology and body sizes, Hippopotamus amphibius(hippopotamus, mega non-ruminant) and cattle(ruminant), by integrating foraging relationship herbivores. We analysed the significant relationships between species dropping densities and environmental variables across forty-eight 100 m×100 m plots in Bui National Park,Ghana, during the wet and dry seasons. We found that both species utilised areas closer to the river in the wet season, but the H. amphibius foraged further away from the river during the dry season. Sward height also determined patch use by both species, with the H. amphibius utilising shorter swards than the cattle. Considering the quality of food resources, the study revealed that patch selection of ruminants(cattle) was significantly influenced by nitrogen content. In contrast, acidic detergent fibre content was positively related to non-ruminant species(***). The high seasonal effect of sward height and food quality on patch use is primarily due to the species digestive physiology and body size of hippopotamus and cattle at the Bui National Park.

关键词： digestive physiology herbivore mammals foraging hippopotamus

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Feeding ecology of the mangrove oyster, <i>Crassostrea gasar</i>(Dautzenberg, 1891) in traditional farming at the coastal zone of Benin, West Africa

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Natural Science 2013年第12期5卷 1238-1248页

作者： Alphonse Adite Stanislas P. Sonon Ghelus L. Gbedjissi Laboratoire de Parasitologie & Ecologie Parasitaire Département de Zoologie Faculté des Sciences et Techniques Université d’Abomey-Calavi Cotonou Bénin PRECOB Unité de Recherches sur les Zones Humides (URZH) Département de Zoologie Faculté des Sciences et Techniques Université d’Abomey-Calavi Cotonou Bénin

Wild collection management and farming of the mangrove oyster (Crassostrea gasar) occurring widely at the Benin (West Africa) coastal zone require knowledge on the feeding ecology to explore energy sources and nutritional needs. Six hundred thirty (630) individuals of C. gasar have been sampled in the rearing site at the Benin coastal lagoon to investigate on the trophic ecology of this cultivated bivalve. The diet analysis revealed that C. gasar is a filter-feeder foraging mainly on phytoplankton (72.70%) and substrate particles (22.95%). This trophic specialization results from anatomical structure, mainly the presence of gills which facilitate the filtering of number of plankton taxa. Dominant phytoplanktons ingested comprised of Diatomophycea (33.52%), Chlorophycae (17.19%), Scenedesmacae (13.80%), Dictyosphaeriacae (3.79%), and Pleurococcacae (2.75%). Eight genuses of phytoplankton, Polycystis, Coelosphaerium, Protococcus, Botryoccocus, Crucigenia, Melosira, Cyclotella, and Gyrosigma dominated the diet of C. gasar with aggreated volumetric proportions reaching 69.06% of the diet. Higher occurrences were recorded mainly for Melosira occurring in 263 (41.75%) stomachs, substrate particles in 211 (33.49%), and Polycystis in 151 (23.97%). C. gasar exhibited a high niche breadths varying from 4.54 to 5.78, suggesting that this bivalve consumed a high variety of food items, thus exhibiting a degree of trophic plasticity. Diet overlaps (?jk) among different size classes were high and varied from 0.71 to 0.98, indicating an ontogenetic diet shift pattern in C. gasar. Probably, to adapt to the benthic-muddy environment and to increase survival, C. gasar has evolved a specialized feeding mechanism and strategy to retrieve only needed nutrients for growth and to reject awful and nondigestible foods. Also, at the oyster rearing grounds, there is an evidence of shift in the food web structure leading to an increase of the biological productivity at the coastal zone. The out

关键词： Conservation Crassostrea Diet Overlaps Farming Filter-Feeder Food Web foraging Strategy Phytoplankton

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Habitat Selection by Large Mammals in South Luangwa National Park, Zambia

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Open Journal of Ecology 2017年第3期7卷 179-192页

作者： Harry Chabwela Chansa Chomba Gilson Kaweche Ackme Mwenya Department of Biological Sciences University of Zambia Lusaka Zambia School of Agriculture and Natural Resources Disaster Management Training Centre Kabwe Zambia Department of National Parks and Wildlife Service Chilanga Zambia

An assessment to determine habitat selection by large mammals was carried out in South Luangwa National Park, eastern Zambia. We divided Habitat types into five groups based on physiognomic classification as: savannah wood-land, back swamp, Combretum thicket, Mopane woodland, and Terminalia-Erythrophleum. Road count method was used to sight animals across the four identified habitat types. Results showed that puku, impala, elephant, and zebra were highly selective of habitat types. Puku occurred mainly in back swamp habitat (86.6%) followed by water buck (75.0%), elephant (72.3%) and zebra (65.7%). Impala were more abundant in Terminalia-Erythrophleum woodland (69.50%) while buffalo was mainly sighted in Mopane-woodland (45.07%). Other species were more cosmopolitan. It was suggested that foraging behaviour, season and security with respect to predation were the factors singularly or collectively that influenced the observed pattern of habitat selection by large mammals.

关键词： Assessment foraging Road Count Occurrence Physiognomic Classification

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Study on the Hierarchical Route Planning Underthe Emergent Threats

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计算机科学与技术汇刊（中英文版） 2017年第1期6卷 1-7页

作者： Caikun Zhang Zhongfu Xu Ying Cheng Danhui Sun Luoyang Electric Equipment Test Center Luoyang 471003 China

Hierarchical route planning method under the emergent threats is put forward for the emergent threats in the route planningproblem. First, the basic ideas and framework of hierarchical planning are put forward on the basis of constraints of routeplanning. Then, the primary flight corridor planning of the bacterial foraging algorithm based on Gaussian distribution estimationalgorithm and secondary optimal route planning based on heuristic A ＊ algorithm are put forward in this paper. The primaryplanning effectively reduces planning domain, and the secondary planning is based on the primary planning. Real-time routeplanning can be carried out quickly and efficiently and the emergent threats can be effective to deal with. Finally, the simulationresults prove that this method is not only scientific and reasonable, it also can effectively narrow the domain range and plan theroute in real-time to avoid emergent threats.

关键词： Route Planning Bacterial foraging Algorithm Gaussian Distribution Estimation Algorithm Heuristic A*Algorithm

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Evolutionary MPNN for Channel Equalization

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Journal of Signal and Information Processing 2011年第1期2卷 11-17页

作者： Archana Sarangi Bijay Ketan Panigrahi Siba Prasada Panigrahi Department of AEIE ITER SOA University Bhubaneswar India Department of Electrical Engineering IIT Delhi India Department of Electrical Engineering KIST Bhubaneswar India

This paper proposes a novel equalizer, termed here as Evolutionary MPNN, where a complex modified probabilistic Neural Networks (MPNN) acts as a filter for the detected signal pattern. The neurons were embedded with optimization algorithms. We have considered two optimization algorithms, Bacteria foraging Optimization (BFO) and Ant Colony Optimization (ACO). The proposed structure have the ability to process complex signals also can perform for slowly varying channels. Also, Simulation results prove the superior performance of the proposed equalizer over the existing MPNN equalizers.

关键词： Channel Equalization Probabilistic Neural Network Bacteria foraging Ant Colony Optimization

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Comparisons of Group-Size, Composition and Movement of Herbivorous Reef Fish in Jamaica and Grand Cayman Island

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Open Journal of Marine Science 2020年第1期10卷 1-15页

作者： Layla Al-Shaer Andrew Bloch Matthew Draud Brandon Baumann Murray Itzkowitz Department of Biological Sciences Lehigh University Bethlehem PA USA College of Arts and Sciences Siena Heights University Adrian MI USA

The decline in herbivorous fishes is an important contributing factor to the degradation of coral reefs, because their reduction contributes to macro algae overgrowth, which can have harmful effects on corals. Herbivorous fish often form mixed-species groups to locate foraging sites and for defense. The movements and compositions of these groups are dependent on the relative numbers of different species present. Some species, such as the striped parrotfish (Scarus iserti) and ocean surgeonfish (Acanthurus bahianus), serve as core species that lead mixed-species groups. Others, such as the redband (Sparisoma aurofrenatum) and stoplight parrotfishes (Sparisoma viride), follow core species as their associates. Despite the potential importance and abundance of mixed-species groups on reefs, little attention has been given to their composition and movements. Our intent was to determine whether the social dynamics of mixed-species groups in Jamaica were similar to those of Grand Cayman. The overall sizes of mixed-species groups were smaller in Grand Cayman. Focal striped parrotfish in Grand Cayman formed smaller groups, changed composition less, and moved less frequently than in Jamaica. Although probably more abundant than striped parrotfish, the ocean surgeonfish in Grand Cayman did not function as a core species but rather attached themselves as associates to the smaller striped parrotfish groups. Redband parrotfish moved less often in Grand Cayman, and appeared to be more dependent on striped parrotfish groups than stoplight parrotfish. While previous studies on herbivorous reef fish have shown that changes in foraging patterns can change with location, perhaps related to structural heterogeneity and resource distribution, this study illustrates that social interactions between common members of mixed-species groups also change. We suggest that the intra and interspecific social interactions in Grand Cayman are less attuned to finding erratically located high quality

关键词： Coral Decline foraging Behavior Algae-Grazing Herbivore Scaridae Acanthuridae

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