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    The effect of dietary microalgae on the fatty acid profile, fecundity and population growth of the calanoid copepod Pseudodiaptomus hessei (Mrázek 1884) (Copepoda: Calanoida)
    (University of Fort Hare, 2016) Siqwepu, Oyama
    This study compares the efficiency of different dietary microalgae on the fatty acid profile, especially the essential fatty acids Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) of the calanoid copepod Pseudodiaptomus hessei (Mrázek 1884), a potential live food for finfish larvae in aquaculture. The effect of different dietary microalgae on fecundity and population growth was also investigated. Two mono-algal diets, the Tahitian strain of Isochrysis galbana (Parke) and Rhodomonas salina (Wislouch) and a 50:50 binary diet of the two were fed to copepods. Wild caught copepods were used as a baseline reference point. Copepods fed I. galbana had the highest DHA: EPA ratio and DHA content; although it was not significantly different from those fed the 50:50 binary diet, it significantly differed from those fed R. salina. The EPA content was similar for all three diets. Copepods were collected and preserved in 10 % buffered. The membrane sac was dissolved in a 5 % solution of sodium hypochlorite and gently agitated to dissolve the egg sac. Copepods fed R. salina produced the highest number of eggs per female (34.60 ± 5.97 eggs/female (mean ± standard error)), and were significantly different from those fed I. galbana (22.8 ± 5.44 eggs/female) and the 50:50 binary diet (23.30 ± 6.77 eggs/female). Copepods were counted under a microscope and each stage of development was identified. The highest population was obtained when the copepods were fed I. galbana (709 ± 92.23 individuals/treatment), and was significantly different from R. salina (433 ± 78.08 individuals/treatment) and the 50:50 binary diet (437 ± 40.02 individuals/treatment) populations. The results of this study show that the fatty acid composition of P. hessei can be altered by feeding a variety of dietary microalgae and that the copepod can accumulate fatty acids from their diet, especially DHA and EPA. It is also evident that diet has an effect on fecundity and population development. This makes P. hessei an ideal live food candidate for marine finfish larvae as its nutritional composition and productivity can be manipulated to suit the needs of marine finfish larvae. Based on this study, it is suggested that a 75: 25, I. galbana to R. salina treatment be tested in order to improve both fecundity and population growth.
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    The influence of mite predation on the efficacy of the gall midge, Dasineura sp., as a biocontrol agent of Australian myrtle, Leptospermum laevigatum (Myrtaceae) in South Africa.
    (University of Fort Hare, 2010) Mdlangu, Thabisa L.H.
    Dasineura sp. is a gall forming midge that was introduced into South Africa for the biocontrol of the Australian myrtle, Leptospermum laevigatum. It causes galls on both the vegetative and reproductive buds of the plant. Although Dasineura sp. was initially regarded as a potentially successful agent, galling up to 99% of the buds of the host plant, it has been preyed on by native opportunistic mites, which caused a decline in the performance of the midge as a biocontrol agent of L. laevigatum. This raised a concern about whether this fly will be able to perform effectively in the presence of its new natural enemies. Therefore, the objectives of this study were to: 1) ascertain whether mite abundance has seasonal variations; 2) determine if plant density and plant size have an effect on midge predation by the mites; and 3) determine if midge predation varies in different locations. The study was conducted at three sites in the Hermanus area, Western Cape Province. Every three weeks for thirteen months, galls were collected and dissected so as to count and record the numbers of midge larvae, pupae, adults and mites that were found. Data collected showed that predation varied with season, and the mites were scarce during the flowering season. Predation also varied among the study sites and plant density had an effect on midge predation. Midges in smaller plants (saplings) were more vulnerable to predation than those in the bigger plants (plants from isolates and thickets). It was concluded that although mites have an effect on midge populations, they do not prevent their establishment on the plant. Therefore, a survey should be done in two to three years time to check if the midges are still persisting on the plant, and recommendations are that a new agent should be released to supplement the midges.
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    Identification and documentation of ethnobiological methods used by rural farmers to control stalk borers on maize in the Eastern Cape province of South Africa.
    (University of Fort Hare, 2014) Mlanjeni, Nolitha Leonora
    Maize contributes substantially to food security in the Eastern Cape province of South Africa. It is a staple food to many of the province’s rural and urban inhabitants. Insect pests are one of the factors that hamper its productivity and as a result, deprive farmers of good yields. The adverse effects of insecticides and the high cost associated with them and the cost of transgenic seeds are some of the challenges faced by small-scale farmers in rural areas. Alternative control methods which include the use of indigenous techniques to control pests are now sought. A study to identify and document ethnobiological means used by rural farmers to manage insect pests of maize was conducted in the rural areas of the Eastern Cape Province. A total of 217 participants were interviewed on the matter, using semi-structured but detailed questionnaires. Rural farmers due to their linkage to agriculture activities and the fact that they are considered as custodians of agricultural indigenous knowledge were selected as respondents. Only maize producing and IsiXhosa speaking people were chosen to contribute. Main focus was on the demography of respondents, crop production activities and insect pest control. Pretesting of the questionnaire in order to assess the appropriateness of questions and comprehension by both farmers and enumerators was done. Data was analysed using descriptive statistics. Fifty five percent (55 %) of the respondents were females and the highest number of participants was from the Chris Hani District Municipality. Majority of the people were unemployed or pensioners. Most had only attended primary school and the mean age was 59 years. Apart from maize, respondents were cultivating other crops such as cabbage, Swiss chard, potatoes etc. Stalk borers followed by cutworms were the main pests of maize in these areas. Respondents used mainly insecticides, followed by alternative substances, which also included cultural control methods such as planting date manipulation. Few respondents used iv plants as control agents for insect pests. Some people did not control pests even though they were a problem in their fields. The most used plant was Chenopodium ambrosiodes L, while the most used substance was Madubula (a detergent). The most used insecticide was carbaryl from the carbamite family. Respondents listed different preparation techniques for all the control methods mentioned. These techniques revealed different times of preparation, quantities of ingredients, amounts applied on plants, modes of application and intervals of application. Rural farmers in the study areas used different atypical methods which may play a significant role in pest management today. Some of the products may have a positive influence on agriculture, while some are dangerous to humans and environmental health. Further research which will investigate their potential use in pest control needs to be done.
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    A comparative evolutionary approach to gum-feeding in Galago moholi and Microcebus griseorufus.
    (University of Fort Hare, 2014) Andrews, Curswan Allan
    Gums are soluble plant exudates rich in complex carbohydrates. In primates, the consumption of gum (gummivory) has been described as a primitive, fall-back diet exhibited when other food sources become scarce, particularly during dry periods. In apparent support for this interpretation, gummivory is often observed in nocturnal strepsirhines (tooth-combed primates) believed to have retained many primitive features. The complex carbohydrates in gums, however, are also known to be difficult to digest, and require particular alimentary adaptations. The hypothesis of a primitive diet predicts that gummivorous strepsirhines should use homologous digestive strategies, while the presence of different digestive adaptations in different lineages would suggest convergent evolution. I compared the digestive adaptations to gummivory in two small strepsirhine taxa, African lesser bushbabies (Galago moholi) and Malagasy reddish-grey mouse lemurs (Microcebus griseorufus). Both taxa digest gum primarily by fermentation, and have enlarged caeca for this process, but only G. moholi has an ansa coli in which digestion can be continued. In captive feeding experiments, the faeces of wild-caught G. moholi and M. griseorufus showed no significant difference in their digestive efficiency of gum compared with a control food (banana), and the banana and gum samples showed no significant difference in nutrient concentration and overall composition. To gain a broader understanding of the origins of gummivory in strepsirhines, I used a phylogenetic method to reconstruct their dietary evolution. My results indicate that gummivory evolved convergently in several primate lineages, apparently in response to environmental hypervariability. I conducted biochemical analyses of the secondary compounds found in gums that are regularly consumed, and preliminary results show that Commiphora spp. have a number of compounds, while Acacia spp. show no such traces. The absence of secondary compounds from M. griseorufus faeces suggests that the animals have physiological means for either converting them into digestible products or detoxifying and excreting them in their urine. Finally, I compared the distribution patterns of G. moholi and M. griseorufus with climatic parameters; both study taxa inhabit regions in which the dry season is characterised by little to no rainfall, a drought that may persist for months. Similar climatic regions are occupied by other gum-feeders, including the marsupial gliders (Petauridae) of Australia.
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    Morphological and genetic variation in samango monkeys (Cercopithecus albogularis) in southern Africa
    (University of Fort Hare, 2013) Makhasi, Ntuthuzelo
    My aim was to resolve the taxonomy of the South African forms of Cercopithecus albogularis by exploring morphological and genetic variation in the two samango subspecies described for the region: C. a. erythrarchus and C. a. labiatus. In addition, I estimated their geographic distributions and habitat requirements from the provenance data I collected during my study of museum specimens. My analysis has shown clear morphological differences between C. a. labiatus and C. a. erythrarchus. The two subspecies differ in pelage coloration, but also in cranial shape and tail lengths. Furthermore, C. a. labiatus is slightly smaller, shorter-tailed and stocky compared with the long-tailed slender northern forms of C. albogularis, which may be adaptations to cold environments like montane forest. The northern C. albogularis subspecies are distinguishable from the southern taxa with a high degree of reliability (98.5%), suggesting that C. albogularis consists of more than one species. The most appropriate name for the southern species is C. labiatus. My genetic study did not detect variation among the 10 animals sampled in Hogsback; while it clustered the different taxa, it could not resolve relationships between them, with the exception of the outgroup. The lack of resolution of the deeper nodes could be a result of the fact that our sequence was very short (274 bp). The mt 12S rRNA gene was not an ideal gene for this study, which should have involved a less conserved section of the mtDNA molecule, like the rapidly evolving D-loop. More genetic work is clearly needed to resolve the phylogenetic relationships within the C. mitis supergroup. However, preliminary genetic data indicate that the southern samangos are distinct from the C. mitis of West Africa, while my morphometric study suggests they may also be distinct from C. albogularis in East Africa. Molecular and karyological studies comparing the genomes of Hogsback “C. a. labiatus” with the neighbouring “C. a. erythrarchus” and Zanzibar C. albogularis would be extremely enlightening.
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    Diet and microhabitat use of the woodland dormouse Graphiurus murinus at the Great Fish River Reserve, Eastern Cape, South Africa
    (University of Fort Hare, 2014) Lamani, Siviwe
    The diet of the woodland dormouse Graphiurus murinus was studied in a riverine Combretum forest at the Great Fish River Reserve (Eastern Cape, South Africa). Food remains were collected seasonally from a maximum of 45 different nest boxes between December 2010 and November 2011. An overall mean of 1.32 } 0.51 food categories (range 1–4) were identified in each nest box used as “larder” during the year. Dietary diversity and standardized diet breadth were low to intermediate, with a peak in summer and a nadir in winter. In terms of percentage occurrence, arthropods were dominant (99%) in all seasons, followed by molluscs (16%) and fruits (14%). When relative percentage occurrence and percentage weight were considered, arthropods were still dominant, but a slight decrease was observed in summer. Besides spiders (order Araneae), nine arthropod families were found in the diet of the woodland dormouse; Tenebrionidae (40%), Spirostreptidae (30%), Carabidae (15%) and Blattidae (14%) were the most dominant families in terms of percentage weight. Grewia robusta and Ziziphus mucronata were the only fruit species present in the diet. Pianka’s diet overlap indices were very high (>0.93), indicating that the diet of the woodland dormouse was similar between pairs of seasons. This study also investigated whether woodland dormice Graphiurus murinus positively select or avoid specific microhabitat types or structures, and whether a set of predictor variables related to microhabitat characteristics can explain the presence and rates of visits to specific trapping stations. Trapping was conducted seasonally, over 5 days, between June 2011 and April 2012. A grid of 96 stations (16 rows × 6 lines) was established. Trap stations were set at 10-m intervals. At each station two Sherman traps were placed. The 192 traps were distributed relatively equitably among four height categories (0–0.5 m, 0.51–1 m, 1.01–1.5 m, and 1.51–2.5 m). On average, trapping success was 4.70 +- 4.17 dormice per 100 traps. Dormice were trapped at an average height of 136 +- 64 cm, which was significantly higher than the average height at which traps were set (99 +-75 cm). Bonferroni Z tests indicated that dormice positively selected areas with high canopy cover and connectivity, possibly to decrease predation risk. Generalized Linear Models showed that trap use and numbers of visits and different animals caught were positively associated with a high arboreal connectivity, hence supporting the hypothesis that woodland dormice may depend on wooden “corridors” for their movements.
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    Diet of the yellow mongoose (Cynictis penicillata) in the Albany Thicket Biome of South Africa.
    (University of Fort Hare, 2014) Bizani, Mfundo; Do Linh San, E.
    The dietary habits of the yellow mongoose Cynictis penicillata were studied in the Albany Thicket Biome of South Africa (Great Fish River Reserve, Eastern Cape). The diet was investigated through the analysis of 1,056 scats that were sampled over a period of 7 years (2005−2009 and 2011−2012) mainly in three similar sites (Kelarny, Grasslands and Junction 10) that were used by at least three families or groups of yellow mongooses. Scats were collected near latrine sites, labelled and stored in a freezer. In the laboratory, scats were ovendried for a period of 24 hours at 50 C. Diet was determined by identifying undigested food remains in the scats. Hair samples were examined under the compound microscope to identify which mammals were ingested. In the field, both arthropod and small mammal abundance were determined in order to evaluate whether yellow mongooses are opportunistic or specialist feeders. Furthermore, inter-annual (2006–2008) and inter-group/inter-site variations in the diet were assessed. Based on faecal analysis, arthropods were the principal prey, while small mammals acted as supplementary food item. Other food categories like vegetation, reptiles and birds were only ingested or preyed upon infrequently. Intermediate dietary diversity, and low standardised diet breadth indices were obtained for all seasons, as well as for the whole sampling period. The diet overlaps calculated for pairs of seasons were very high and did not differ substantially. However, the diet of the yellow mongoose varied seasonally, yearly and between groups (sites), mostly due to variations in arthropod and small mammal consumption. Food availability displayed an increase in biomass of both small mammals and arthropods in summer and autumn. Results obtained in this study could suggest that the yellow mongoose at the GFRR is insectivorous by preferring to feed on insects (and arthropods in general) when both insects and rodents are abundant. However the fact that its diet varies both seasonally, yearly and locally, as well as the presence of remains of other food categories in the scats, indicates that this species is rather an opportunistic, generalist feeder than an insect specialist.
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    Resting site ecology and microhabitat use of the Mozambique thicket rat (Grammomys cometes) in a riverine Combretum forest
    (University of Fort Hare, 2014) Gebe, Zimkhitha
    Very little is known about the resting and spatial ecology of the Mozambique thicket rat, Grammomys cometes, a rodent species distributed in two disjoint populations in South Africa and Mozambique. The present study focused on determining the characteristics and usage patterns of resting sites, as well as the microhabitat use and selection of this species during its activity period. Broadly, I predicted that resting ecology and space use would be affected by environmental, climatic, social and sexual factors. I also hypothesized that predatory risk could affect thicket rat behaviour. Field work took place in the Great Fish River Reserve complex (Eastern Cape Province, South Africa), in a stretch of riverine Combretum forest (length × breadth: ca. 500 × 100 m) located in the western section of the conservation area. Overall, 38 different rats (22 males and 16 females) were trapped and radio-tracked for varying periods between July 2011 and November 2012. Individual rats used a mean of 2.54 1.89 different resting sites (range: 1–9) during each tracking session and resting-site fidelity averaged 85 17%. Overall, 27% of the 131 resting sites identified were artificial wooden nestboxes, 45% were inside branches, 21% were inside trunks, 3% were located on the ground, 2% in bushes, 1% inside dead logs, with one uncertain location (1%). Cape bushwillows Combretum caffrum were the predominant trees (60.32%) used for the resting sites, probably due to their abundance in the forest, and their propension to rot from the inside and provide natural cavities. The mean height of resting sites used by thicket rats was 217 119 cm, and the mean circumference of branches and trunks was 79 35 cm, with no seasonal and sexual variation. In contrast, males exhibited an overall lower percentage usage of individual resting sites than females, probably due to their increased movements during the long mating season. Percentage usage was significantly higher during the cold season, likely for thermoregulatory seasons. Nearly 50% of the resting sites were shared with an average (SD) of 3.20 1.25 individuals (range: 2–6). However, simultaneous use of resting sites only took place in about 8% of locations. Sharing involved 2–3 males in 90% of the cases. It is suggested that females are solitary but not territorial, while at least some males are more social or tolerant towards each other, and have overlapping ‘home ranges’. These observations could be indicative of a promiscuous mating system. Microhabitat use and selection were determined by conducting a 5-day trapping session during each season between June 2011 and May 2012. A grid of 96 stations (16 rows 6 lines) was set at the study site, with pairs of traps per station placed at 10-m intervals, at different heights and on different types of vegetative stands. Several variables describing microhabitat structure were recorded seasonally at each station. Thicket rats (38 individuals captured 91 times) were captured mostly at night, with an overall trapping success of 2.16 0.27% over the year. The average height at which rats were trapped (140 65 cm) was significantly higher than the height of traps set in the field (99 ± 75 cm). A large proportion of traps (31.3%) where rats were caught were placed on Combretum caffrum trees, and majoritarily on trunks (46%), tree canopy (19%) and woody lace (19%). Bonferroni Z tests indicated that thicket rats actively avoided trap stations with less than 50% canopy cover as well as areas that had arboreal connections in less than 50% of the directions. Rats also significantly avoided traps that were set in bushes and on the ground, irrespective of whether these were situated in open terrain or surrounded by some vegetation. Generalized Linear Models confirmed that two main predictors (Cover >150 cm and height) had a significant positive effect on the use of traps and on the numbers of visits to, and different animals caught at, trapping stations. All other variables, including connectivity with the surrounding vegetation, tree species, vegetation type and position in which the traps were placed, and tree trunk/branch circumference at trap height, did not have any significant effects. This study confirms that thicket rats are essentially nocturnal, arboreal and prefer dense canopy cover, possibly because this decreases predation risk at the microhabitat level.
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    Regional differentiation of three goatfishes (parupeneus spp.) within the Western Indian Ocean
    (University of Fort Hare, 2015) Springbok–Njokweni, Nosiphiwo
    Goatfishes inhabit inshore reefs and corals and are commercially important across their distribution in the Western Indian Ocean (WIO). The biogeography of these species in the WIO has not been explored with regards to their levels of diversity and relationships among regions. The genetic connectivity and differentiation of three goatfishes of the genus Parupeneus (P. barberinus, P. macronemus and P. rubescens) was studied using two mitochondrial genes (ND2 and 16S rRNA) and one nuclear gene (RAG1) using specimens from East and southern Africa, islands around the Mascarene plateau, Oman, Maldives and the Red Sea. Haplotype diversities, networks and AMOVA were used to measure genetic variance among localities and defined regional groups. There were high haplotype (HD > 0.9) and low nucleotide diversities (< 0.006) among all species for all gene regions, suggesting high levels of genetic differentiation among different areas, except for the mtDNA 16S data for P. macronemus and P. rubescens. For all three species, the FST population pairwise values revealed significant differentiation in all datasets for most population pairwise comparisons with the Maldives and genetic connectivity with haplotypes being shared among other localities. The 16S and RAG1, AMOVA for P. barberinus revealed a significant (P < 0.05) strong genetic structure among groups, for example P = 0.00 was estimated in the 16S data for four groups (the Maldives, WIO islands, Kenya and eastern mainland). This study found evidence for regional differentiation within the WIO for these three species supporting the presence of genetic breaks among areas. This differentiation could be either due to the historical isolation among areas or due to geographic and oceanic barriers such as the Mascarene Plateau and the Agulhas Current eddies in the Mozambique Channel. The effects of oceanographic features and physical barriers in the species distribution range and the dispersal potential based on the life history features of the species can have an influence on the genetic structuring of a population. It is also important to note that the length of the pelagic larval phase is just one factor affecting dispersal in marine organisms that can also explain the difference in genetic population structure. Unfortunately there is no specific information on the larval dispersal of these three goatfish. Therefore, studies are needed to be conducted on the specific biology and life history strategies of each Parupeneus species. These results suggest the importance of other factors, such as currents, and larval retention that may cause strong differentiation. These factors should also be considered when observing larval dispersal and its effect on population genetic structure. This study support the hypotheses that physical factors, processes (geographic barriers and oceanographic characteristics) and life history parameters need to be studied to understand the genetic differentiation of these Parupeneus reef fishes.
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    Distribution, habitat structure and troop size in Eastern Cape samango monkeys Cercopithecus albogularis labiatus (Primates: Cercopithecoidea).
    (University of Fort Hare, 2016) Martins, Vusumzi; Masters, J; Génin , F.
    The samango monkey subspecies Cercopithecus albogularis labiatus is endemic to South Africa, and known to occur in Afromontane forests. There has been a major decline in this subspecies, exceeding 30% in some populations over the past 30 years, primarily as a result of the loss of suitable habitat. A second samango subspecies, C. a. erythrarchus, occurs near the northern border of South Africa, mainly in coastal lowland forest, and the distributions of the two subspecies do not overlap. C. a. labiatus was thought to be confined to Afromontane forests, but the study described here focused on C. a. labiatus populations that were recently identified in the Indian Ocean Belt forests near East London. I undertook to assess the distribution of C. a. labiatus in the Eastern Cape, to evaluate the habitat structures of the Afromontane and Indian Ocean coastal belt forests, and to understand the effect these habitats have on essential aspects of the socio-ecology of the C. a. labiatus populations. Distribution surveys were conducted in protected areas throughout the Eastern Cape, and samango monkeys were found to be present within forest patches in the Amatola Mountains, Eastern Cape dune forests and the Transkei coastal scarp forests. The sizes and composition of two troops were assessed: one troop in the Amatole forests and one in the Eastern Cape dune forests. The Amatola Mountain troop had a mean troop size of 28.8 ± 7. 8, while that the dune forest mean troop size was 29.1 ± 9.7. C. a. labiatus was found to be distributed in forest patches where the subspecies was previously thought to not be present. The structures of the different forests proved to have no significant effect on these fundamental aspects of socio-ecology within the subspecies
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    The effect of dietary microalgae on the fatty acid profile, fecundity and population growth of the calanoid copepod Pseudodiaptomus hessei (Mrázek 1884) (Copepoda: Calanoida).
    (University of Fort Hare, 2016) Siqwepu, Oyama;
    This study compares the efficiency of different dietary microalgae on the fatty acid profile, especially the essential fatty acids Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) of the calanoid copepod Pseudodiaptomus hessei (Mrázek 1884), a potential live food for finfish larvae in aquaculture. The effect of different dietary microalgae on fecundity and population growth was also investigated. Two mono-algal diets, the Tahitian strain of Isochrysis galbana (Parke) and Rhodomonas salina (Wislouch) and a 50:50 binary diet of the two were fed to copepods. Wild caught copepods were used as a baseline reference point. Copepods fed I. galbana had the highest DHA: EPA ratio and DHA content; although it was not significantly different from those fed the 50:50 binary diet, it significantly differed from those fed R. salina. The EPA content was similar for all three diets. Copepods were collected and preserved in 10 % buffered. The membrane sac was dissolved in a 5 % solution of sodium hypochlorite and gently agitated to dissolve the egg sac. Copepods fed R. salina produced the highest number of eggs per female (34.60 ± 5.97 eggs/female (mean ± standard error)), and were significantly different from those fed I. galbana (22.8 ± 5.44 eggs/female) and the 50:50 binary diet (23.30 ± 6.77 eggs/female). Copepods were counted under a microscope and each stage of development was identified. The highest population was obtained when the copepods were fed I. galbana (709 ± 92.23 individuals/treatment), and was significantly different from R. salina (433 ± 78.08 individuals/treatment) and the 50:50 binary diet (437 ± 40.02 individuals/treatment) populations. The results of this study show that the fatty acid composition of P. hessei can be altered by feeding a variety of dietary microalgae and that the copepod can accumulate fatty acids from their diet, especially DHA and EPA. It is also evident that diet has an effect on fecundity and population development. This makes P. hessei an ideal live food candidate for marine finfish larvae as its nutritional composition and productivity can be manipulated to suit the needs of marine finfish larvae. Based on this study, it is suggested that a 75: 25, I. galbana to R. salina treatment be tested in order to improve both fecundity and population gowth.