Showing papers by "University of Zimbabwe published in 1987"
TL;DR: Nine branching process models, which differ in assumptions regarding the regulation of transposition and the effect of copy number on fitness, have been evaluated and there is a highly significant positive association among the insertion sequences considered in the aggregate.
Abstract: A reference collection of 71 natural isolates of Escherichia coli (the ECOR collection) has been studied with respect to the distribution and abundance of transposable insertion sequences using DNA hybridization. The data include 1 173 occurrences of six unrelated insertion sequences (IS 1, IS2, IS3, IS4, IS5 and IS30). The number of insertion elements per strain, and the sizes of DNA restriction fragments containing them, is highly variable and can be used to discriminate even among closely related strains. The occurrence and abundance of pairs of unrelated insertion sequences are apparently statistically independent, but significant correlations result from stratifications in the reference collection. However, there is a highly significant positive association among the insertion sequences considered in the aggregate. Nine branching process models, which differ in assumptions regarding the regulation of transposition and the effect of copy number on fitness, have been evaluated with regard to their fit of the observed distributions. No single model fits all copy number distributions. The best models incorporate no regulation of transposition and a moderate to strong decrease in fitness with increasing copy number for IS1 and IS5, strong regulation of transposition and a negligible to weak decrease in fitness with increasing copy number for IS3, and less than strong regulation of transposition for IS2, IS4 and IS30. NSERTION sequences are a special class of transI posable elements found in prokaryotes that have been studied extensively in Escherichia coli K12 (CALOS and MILLER 1980). They usually range in size from 1 to 2 kilobasepairs (kb) and contain perfect or nearly perfect inverted terminal repeat sequences. The terminal sequences flank a unique central sequence with at least one long open reading frame coding, presumably, for the transposase protein. One evolutionary implication of insertion sequences derives from their mutagenic activity in causing insertion mutations. The ability of insertion sequences to inactivate genes
154 citations
TL;DR: Most peasant households in Zimbabwe use edible fruits of indigenous woody plants, and wild fruits, often the only source of fruit for households, are used mostly by children.
Abstract: Most peasant households in Zimbabwe use edible fruits of indigenous woody plants. Deforestation does not significantly affect availability of selected fruits, because people tend not to cut selected trees when clearing land for cultivation. A different range of species is used in the different natural regions of Zimbabwe. Fruit use mainly occurs in the periods of seasonal food stress, even though these seasons are not necessarily the periods of maximum fruit abundance. Wild fruits, often the only source of fruit for households, are used mostly by children. There is a significant trade in wild fruits.
140 citations
TL;DR: The first direct dating of the depositional age of a sedimentary carbonate rock using long-lived radioactive decay schemes was reported in this paper, which yields a Pb/Pb isochron age of 2,839±33 Myr.
Abstract: Here we report the first direct dating of the depositional age of a sedimentary carbonate rock using long-lived radioactive decay schemes. The Mushandike stromatolitic limestone, from the Masvingo (formerly Fort Victoria) greenstone belt of southern Zimbabwe1,2, yields a Pb/Pb isochron age of 2,839±33 Myr. Published claims3 for an age of ˜3.5 Gyr for the Mushandike limestone were based on its supposed intrusion by the Mushandike granite, for which a Rb–Sr whole-rock age of 3,445±260 Myr had been reported4. New Rb–Sr and Pb/Pb isotope data for the Mushandike granite indicate a probable emplacement age of ˜2,900 Myr, and new field evidence (J.L.O., P.T. & J.F.W., in preparation) suggests that the granite forms part of the basement on which the limestone was deposited. Thus the new dates do not support an age of ˜3.5 Gyr for the algal stromatolites at Mushandike. The Pb/Pb isochron method may have wide applicability to dating the time of deposition of Precambrian fossiliferous and unfossiliferous limestones, and thus to the problem of the antiquity of life.
138 citations
TL;DR: In this article, the authors modeled the topography and gravity anomalies in the area surrounding the East African Rift in Kenya can be modelled as the sum of the effects of surface and subsurface loading of an elastic plate.
Abstract: Summary
The topography and gravity anomalies in the area surrounding the East African Rift in Kenya can be modelled as the sum of the effects of surface and subsurface loading of an elastic plate. Assuming surface and subsurface loading are independent processes, the observed coherence between the 2-D Fourier transforms of Bouguer gravity and topography provides a constraint on the effective elastic thickness or flexural rigidity of the plate. Distinct linear segments of the log gravity power spectrum suggest that components of the gravity field with wavelengths of 250–1000 km are generated predominantly by a density contrast at a depth of about 32 km. Most shorter wavelength gravity anomalies are probably associated with source depths of less than 1 km and indicate variations in thickness of low density sedimentary or volcanic layers or lateral variations in density of the surface rocks. A simple density model based on these estimates and the geology of Kenya consists of a cover layer averaging 0.5 km thick with density 2300 kg m−3, a layer 32 km thick with density 2800 kg m−3, and an underlying half-space with density 3200 kg m−3. Using this density model and assuming loading due to relief on all three density interfaces, the elastic thickness that best predicts the observed coherence in the least squares sense is 25 km (Flexural rigidity of 1.4 × 1023Nm). Amplitudes of loads on the density interfaces can be calculated based on the model response. Topography with wavelength greater than 650 km is locally compensated making surface and subsurface loading indistinguishable. At shorter wavelengths, rift volcanics and volcanic cones including Mts Kenya, Elgon and Kilimanjaro can be identified as surface loads. The largest amplitude subsurface load is an upward directed, regionally supported load beneath the Kenya Dome that may correspond to a region of hot, low density mantle recognized by other geophysical studies. In creating the topography for which surface and sub-surface loading are distinguishable, surface loading is much more important than doming due to subsurface loading.
107 citations
TL;DR: A demographic study of the Nile crocodile Crocodylus niloticus at Lake Ngezi, Zimbabwe, revealed that females predominated in all size classes and among embryos.
Abstract: A demographic study of the Nile crocodile Crocodylus niloticus at Lake Ngezi, Zimbabwe, revealed that females predominated in all size classes and among embryos. The sex of C. niloticus was shown to be determined by the temperature of egg incubation in constant temperature laboratory experiments. At 31 °C and below only females were produced. The threshold temperature for maleness was between 31 ° and 34 °C, but appeared to vary between clutches. The duration of the incubation period varied with temperature and was 110 days at 28 °C, falling to 85 days at 34 °C. Incubation temperature affected hatchling length, but not mass. Hatchlings from incubation at 34 °C were shorter on average than those from incubation at 28 °C and 31 °C, but by three months had outgrown them. There was no sex-related difference in length in a random sample of 200 two-year-old C. niloticus on a crocodile farm. Mean temperatures in wild nests were consistently lower than 31 °C and therefore the male threshold as determined in the laboratory. Embryonic development was slow and hatching success poor. The shallowest eggs in a nest had higher mean temperatures and more advanced embryos than the deepest eggs. They also experienced daily temperature fluctuations of up to 10 °C during which the maximum occasionally rose to 35 °C. Constant temperature incubation was not a good model of field conditions, but the correlation between nest temperatures and embryonic sex is consistent with temperature-dependent sex determination in the wild.
105 citations
TL;DR: The development, validation and application of an enzcyme‐linked immunosorbent assay (ELISA) to the detection of AF in human breast milk will be useful in examining the importance of and interaction between exposure to AF and infection with hepatitis B virus (HBV) early in life.
Abstract: Several epidemiological studies have shown a positive association between dietary exposure to aflatoxin (AF) and an increased incidence of primary hepatocellular carcinoma (PHC). One area in which little information is available is the exposure of newborn children to AF in human breast milk. We report the development, validation and application of an enzyme-linked immunosorbent assay (ELISA) to the detection of AF in human breast milk. The assay allows the quantitation of 2 pg AFM1 per ml of milk using less than 10 ml of sample. A good correlation was observed between ELISA and an hplc-fluorescence technique using naturally contaminated milk at levels up to 40 pg AF per ml. Of 54 samples collected from women in rural villages in Zimbabwe, 6 were found to be positive (11%) in ELISA with levels up to 50 pg AF per ml. No positive samples were detected out of 42 milk samples obtained from women in France. This sensitive and rapid methodology will be useful in examining the importance of and interaction between exposure to AF and infection with hepatitis B virus (HBV) early in life.
98 citations
TL;DR: Lead isotope compositions of nine sulfide concentrates from ore samples from the Sar-Cheshmeh deposit are reported in this article, where the fluid responsible for the potassic alteration and the associated mineralization was essentially magmatic, whereas convecting meteoric water from the country rock acted as a mineralizing solution during phyllic alteration.
Abstract: Lead isotope compositions of nine sulfide concentrates from ore samples from the Sar-Cheshmeh deposit are reported. They range from virtually unaltered granodiorite through varying degrees of potassic alteration to ores showing strong phyllic alteration (sericite veins). The samples without strong phyllic alteration have fairly uniform lead isotope compositions around 206Pb/204Pb=18.6, 207Pb/204Pb=15.6, and 208Pb/204Pb=38.7. Two samples with sericite veins have markedly more radiogenic lead. It is concluded that the fluid responsible for the potassic alteration and the associated mineralization was essentially magmatic, whereas convecting meteoric water from the country rock acted as a mineralizing solution during phyllic alteration. In the context of the plumbotectonics model, the deposit has a typical orogen signature intermediate between primitive and mature island-arc settings.
94 citations
TL;DR: In this article, a sequence of period doubling bifurcations was observed as a parameter was varied, and beyond the accumulation point for the period doubling sequence there was a sequence with the same symbolic dynamics as the states of the U (universal) sequence of Metropolis, Stein, and Stein (1973).
Abstract: In experiments on the Belousov–Zhabotinskii reaction in a flow reactor we have observed dynamical behavior that is described well by one‐dimensional maps with a single maximum. A sequence of period doubling bifurcations was observed as a parameter was varied, and beyond the accumulation point for the period doubling sequence there was a sequence of periodic states that has the same symbolic dynamics as the states of the U (universal) sequence of Metropolis, Stein, and Stein (1973). However, in another experiment with malonic acid from a different vendor, we found that some states with particular symbol sequences occurred in three different parameter ranges rather than in one range as in the U sequence. Analysis of the effect of impurities in the reagents showed that some impurities (e.g., Fe3+ and esters of malonic acid) at concentrations of only a few ppm produced dramatic changes in the dynamics; such impurities are contained in commercially available malonic acid. Experiments with purified malonic acid...
62 citations
TL;DR: A 145 km N-S seismic traverse was deployed to determine the crustal structure of the Limpopo mobile belt in southern Zimbabwe and the nature of its northern boundary with the Zimbabwean craton.
57 citations
56 citations
TL;DR: In this paper, the authors examined the relative effect of legal and extralegal factors on the nolle prosequi decision for a sample of shoplifting cases and found that even among low-seriousness offenses, legal factors are the most important determinants of the decision-making process.
Abstract: A controversial aspect of the prosecutor's authority involves the decision to dismiss all criminal charges even though sufficient evidence exists to prosecute. In this regard, low-seriousness offenses are of particular interest because prior research indicates that extralegal factors are likely to play a role in the handling of these offenses. This study examines the relative effect of legal and extralegal factors on the nolle prosequi decision for a sample of shoplifting cases. Stepwise logistic regression analysis reveals that although race and gender are significant factors, the number of charged offenses and the prior arrest record are most predictive of decision outcomes. This finding suggests that even among low-seriousness offenses, legal factors are the most important determinants of the decision-making process. The analysis also reveals several interaction effects which raise the possibility that the use of social characteristics in criminal justice decisions may be related to perceptions of whic...
TL;DR: The war-cry of Reinhard Bonnke's Christ for All Nations (CfAN) crusade is "From the Cape to Cairo" as mentioned in this paper, with the intention of the CfAN team to take their revival right across the continent.
Abstract: "Africa shall be saved" is the war-cry of Reinhard Bonnke's Christ for All Nations (CfAN) crusade. Another war-cry is "from the Cape to Cairo". These slogans indicate the intention of the CfAN team to take their revival right across the continent. Bonnke predicts that their big tent will be erected in Cairo by the end of the century, by which time, he claims, Africa will be the most Christian continent on earth.
TL;DR: Limnothrissa appears to be stunted in the man-made lakes where it occurs where it grows at a faster rate but to a smaller size than it does in natural lakes (Kivu and Tanganyika).
Abstract: The growth and mortality of the small clupeid fish Limnothrissa miodon were studied in Lake Kariba, a large, man-made lake in central Africa. Growth could be described by the von Bertalanffy equation lt= 74.2 (1—e−0.254(t+0.07)) where length (l) is expressed in millimetres and time (t) in months. The monthly rates of mortality were high and increasing under intensive fishing; in 1983 the total mortality rate Z=1.15 and natural mortality M=0.7. Limnothrissa appears to be stunted in the man-made lakes where it occurs (Kariba and Cahora Bassa) where it grows at a faster rate but to a smaller size than it does in natural lakes (Kivu and Tanganyika). Various hypotheses to account for this are discussed and it was concluded that this is an adaptation to the relatively unstable conditions found in the man-made lakes.
TL;DR: Coital rate was elevated during the ovulatory phase of the menstrual cycle and occurred on onset of LH surge day, and was significantly greater than the mean rate across the entire menstrual cycle.
TL;DR: Children in rural and urban areas near Harare were examined for Giardia lamblia cysts and younger children were more likely to be reinfected than older children, and continued excreting cysts for a longer period of time.
Abstract: .
Stool specimens from 3,038 children in rural and urban areas near Harare were examined for Giardia lamblia cysts. Preliminary studies, using specimens collected on three consecutive days from 157 known cyst passers, showed that over 89% of infections could be diagnosed on single stool specimens by examination of Gomori-stained smears. The overall prevalence of giardial infection was 19.4% with significantly more urban children (21.1%) passing cysts than rural children (16.7%). In urban areas the highest prevalence was in young (5-6 year) children, while in rural areas, the highest prevalence was in older (9-10 year) children. Of 132 children treated with Entamizole® a metronidazole-diloxanide combination, 127 (96.2%) had ceased excreting cysts by the fifth treatment day. Followup examination of these children showed a high rate of reinfection, with 29.6% excreting cysts during the year following treatment. During the same period 13.3% of previously uninfected children had started passing cysts, while over half of infected, but untreated, children had undergone apparent “self-cure.” Younger children were more likely to be reinfected than older children, and continued excreting cysts for a longer period of time.
Book•
01 Jan 1987TL;DR: An overview of the Zimbabwean urban planning experi- ence can be found in this article, where the main focus is on the administrative and statutory framework for planning, highlighting urban development and some approaches adopted for plan- ning.
Abstract: The full article can be accessed at the MSU Special Collections, Class No. HD300.692 WEK,This article provides an overview of the Zimbabwean urban planning experi- ence. It is historical in so far as it tries to examine the colonial and post- colonial experiences in urban planning. The main focus is on the administrative and statutory framework for planning, highlighting urban development and some approaches adopted for plan- ning. A major theme of this article is the continuity in the organizational framework, which has resulted in the relative ineffectiveness of some plan- ning approaches, given the dynamic nature of the urban challenge.
TL;DR: The prevalence of leptospiral titres at a serum dilution of 1:100 was 27%, the most common titres being to antigens from the Sejroe and Tarassovi serogroups.
Abstract: A total of 2,382 sera from 92 herds widely distributed throughout Zimbabwe were screened using the Microscopic Agglutination Test against representatives of 18 serogroups ofLeptospira interrogans and one representative ofLeptospira biflexa. The prevalence of leptospiral titres at a serum dilution of 1:100 was 27%, the most common titres being to antigens from the Sejroe and Tarassovi serogroups. Significantly different proportions of titres were shown among the three farming systems and among the eight provinces of Zimbabwe.
TL;DR: It was concluded that the microelisa was a useful aid to the diagnosis of bovine trypanosomiasis and that there is a need for accurate records of drug use and livestock movements to be kept.
Abstract: In a survey for bovine trypanosomiasis blood smears from 1,617 cattle at 72 sites were examined. Trypanosomes were found in 93 cattle, representing 16% of the cattle in herds in which trypanosomiasis was confirmed. Of the positive cattle 56% had infections withT. congolense, 17%T. vivax and 2.2%T. brucei. Five cattle had mixed infections and in 18 cattle the species was not identified. Sera from 1,352 cattle were tested using microelisa. Ten out of 16 sites, at which no trypanosomes were found in blood smears and at which trypanocides were in use, had over 15% seropositive cattle compared with five of 19 sites at which trypanocides were not in use. It was concluded that the microelisa was a useful aid to the diagnosis of bovine trypanosomiasis and that there is a need for accurate records of drug use and livestock movements to be kept. The serious risk of drug resistant strains of trypanosomes emerging due to the uncontrolled use of trypanocides is emphasised.
TL;DR: In this article, a number of measurements were taken of 104 crocodiles at Ngezi, Zimbabwe and the accuracy of a ratio of 1:7 between head length and total length, used mostly during night counts, was established.
Abstract: Summary
A number of measurements were taken of 104 crocodiles at Ngezi, Zimbabwe. These were used to define the relationship between total length and eight other parameters, particularly those that are associated with size estimation during population surveys. The commonly used ratio between hindfoot (HF) spoor and total length is adjusted to 1:14 where HF 150 mm. The accuracy of a ratio of 1:7 between head length and total length, used mostly during night counts, is established. Preliminary work suggests that these results are applicable to other populations.
RESUMEE
Un nombre de mensurations ont ete relevees sur 104 crocodiles a Ngezi (Zimbabwe). Celles-ci ont servi aetablir la relation existant entre la longueur totale et huit autres parametres, particulierement ceux qui sont lies a revolution de la taille durant les recensements de population. L'indice habituellement utilise entre l'empreinte de la patte arriere (HF) et la longueur totale ajustea 1: 14 quand HF < 150 mm et a 1: 13,5 quand HF < 150 mm. On etablit un indice de 1: 7 entre la longueur de la těte et la longueur totale, en usage lors des comptages nocturnes. Un travail preliminaire suggere que ces resultats sont aussi applicables a d'autres populations.
Journal Article•
TL;DR: Using the Harding Self Report Questionnaire, 448 patients attending a general medical out-patient department at a provincial hospital were screened for hidden psychiatric morbidity over a one- month period and 10,5 per cent of patients found to have underlying psychological problems although presenting somatically.
Abstract: Using the Harding Self Report Questionnaire, 448 patients attending a general medical out-patient department at a provincial hospital were screened for hidden psychiatric morbidity over a one- month period. There were 10,5 per cent of patients found to have underlying psychological problems although presenting somatically. Detection rate by workers was low (4,25%). Stemming from these findings a further study was undertaken at Karanda Mission Hospital using the Harding Self Report Questionnaire as a training instrument and implementing a brief training programme for workers. This second part of the project is reported separately.
TL;DR: Indole metabolites were separated by thin-layer chromatography following organ culture of rat pineal glands with tritiated tryptophan, indicating that in the pineal gland, it is probable that production of methoxyindoles is dependent on the concentration of the various hydroxyindoles and their relative affinities for Hydroxyindole-O-methyltransferase.
Abstract: Indole metabolites were separated by thin-layer chromatography following organ culture of rat pineal glands with tritiated tryptophan. Methoxyindole production was shown to differ substantially from results obtained when pineal glands were incubated with radiolabelled serotonin. The correlation between hydroxy- and corresponding methoxyindoles was, however, remarkably similar to previous results, and indicated that in the pineal gland, it is probable that production of methoxyindoles is dependent on the concentration of the various hydroxyindoles and their relative affinities for hydroxyindole-O-methyltransferase. It is also probable that although several forms of the enzyme may exist in the pineal gland, the catalytic sites are homogeneous in their activity.
TL;DR: The results may suggest that the pineal gland integrates environmental cues to act in concert with physiological thermostats in the fine tuning of thermoregulation.
Abstract: The various pineal gland tryptophan metabolites were administered to male rats intraperitoneally (100 micrograms/kg) and rectal temperatures were recorded. Of the compounds tested, hydroxytryptophan, N-acetylserotonin, hydroxytryptophol, and their corresponding methoxyindoles all caused a marked hypothermia, indicating that several indolic products may be involved in thermoregulation. Although the brain penetration of indoles is poor, a central site of action would be most likely, although peripheral actions cannot be excluded. The mechanism of induction of hypothermia may involve peptides, the pituitary-thyroid axis, the adrenal gland, or a combination of these. These results may suggest that the pineal gland integrates environmental cues to act in concert with physiological thermostats in the fine tuning of thermoregulation.
TL;DR: It was concluded that in Zimbabwe, appreciable grass-associated N 2 -fixation is likely to be restricted to vlei areas (low-lying, seasonally waterlogged areas).
Abstract: Many grass species were screened by the C 2 H 2 reduction assay for associated N 2 -fixation. Most showed positive activity, yet none proved particularly superior to the others. Concentrated study on a few species revealed that N 2 -fixation was greatly depressed as soil moisture decreased to even moderate levels. It was concluded that in Zimbabwe, appreciable grass-associated N 2 -fixation is likely to be restricted to vlei areas (low-lying, seasonally waterlogged areas). N 2 -fixation associated with Paspalum urvillei , a vlei species, was estimated to contribute up to 76 kg N ha −1 yr −1 and had nitrogenase activity of 39–48% of the pasture legume Silverleaf Desmodium.
TL;DR: Clinical and subclinical mastitis were rarely observed, and Staphylococcus aureus was the bacterium most frequently isolated, and there was no association between milking and the presence of mastitis pathogens in the udder.
Journal Article•
TL;DR: Reductions in cholinesterase activity did not correspond with reported symptoms, and levels of protective clothing, knowledge of correct practice of pesticide use and of associated hazards was found to be low in users.
Abstract: Despite rising use of pesticides in agriculture in Zimbabwe, poor monitoring and lack of community-based assessment implies that there is little documentation of the extent and nature of poisoning in the agricultural working class. The paper presents the results of a longitudinal study of exposure to organophosphates in twelve farms in Mashonaland Central during the 1985/6 spraying season. Significant reductions in cholinesterase activity were observed in the group of workers spraying pesticides during the spraying season compared to non-spraying controls in the same period. State farms had significantly lower levels of exposure than private farms. Reductions in cholinesterase activity did not correspond with reported symptoms, given the non-specific nature of these symptoms. Levels of protective clothing, of knowledge of correct practice of pesticide use and of associated hazards was found to be low in users. Regular monitoring of workers using toxic pesticides is recommended.
TL;DR: The rupture en 1921 entre la mission anglaise et les disciples de Simon Kimbangu is plutot due aux missionnaires as discussed by the authors, a.k. a.
Abstract: La naissance du mouvement de Simon Kimbangu dans le Bas-Zaire. L'A. montre qu'il n'est pas apparu en reaction contre l'Eglise missionnaire de la Baptist Missionary Society, mais en continuite consciente avec l'ecclesiologie et les structures de cette Eglise. La rupture en 1921 entre la mission anglaise et les disciples de Kimbangu est plutot due aux missionnaires
TL;DR: The duration of oviposition was shorter in infected females incubated at 25 degrees C or 35 degrees C and infected females laid fewer eggs than the controls and the mean survival period of infected larvae was significantly lower than those of controls.
TL;DR: The leaves of Aloe excelsa afforded, aloesin, anthraquinones and a new compound 2′-p-methoxycoumaroyl]-methylchromone, was established by spectral and chemical means.
TL;DR: No explanation for the arthritis was found and the clinical entity of tropical polyarthritis may not be due to a single aetiological agent.
Abstract: Fifteen consecutive patients with acute arthritis were studied. Careful culture and microscopy of swabs from mucosal sites were performed to examine the hypothesis that the acute tropical polyarthritis commonly seen in Zimbabwe is due to undiagnosed gonococcal infection. Rheumatic fever and Reiter's disease accounted for two cases each. Gram negative intracellular diplococci were found in three patients who would otherwise have been diagnosed as having tropical polyarthritis. Except for two of the remaining eight patients, who had raised anti-streptolysin O titres suggesting recent streptococcal infection, no explanation for the arthritis was found. The clinical entity of tropical polyarthritis may not be due to a single aetiological agent.
TL;DR: Junor et al. as mentioned in this paper conducted a five-year census of fish-eating birds on Lake Kyle, Zimbabwe, and found that eight species were present in significant numbers with the Reed Cormorant being the most abundant.
Abstract: Summary Junor, F. J. R. & Marshall, B. E. 1987. Factors influencing the abundance of piscivorous birds on Lake Kyle, Zimbabwe. Ostrich 58:168-175. A five-year census of fish-eating birds on Lake Kyle, Zimbabwe, revealed that eight species were present in significant numbers with the Reed Cormorant being the most abundant. Dabchicks moved away from the lake to suitable breeding areas during the rainy season. Other species were normally present in greatest numbers in the rainy season. This was determined by fish abundance and there was a correlation between bird biomass and fish abundance. During a drought year more birds remained on the lake in winter, presumably because other water-bodies dried up earlier than usual. There is no evidence that the birds pose a threat to human fishing activities on the lake.