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Sunday, July 28, 2019

Biology Essay Example | Topics and Well Written Essays - 1500 words - 1

Biology - Essay Example (Johansen CA and Mayer D.F, 1990) The importance of pollinators like bees is such that in an extensive report prepared by the Food and Agriculture Organisation (FAO) of the UN it has been found out that 90% of the food supplies that are used for feeding 146 countries, over 71% of the crops were cross pollinated by bees. Other insects included wasps, beetles and wasps. These insects can therefore be considered as critical agents in the food chain as it is responsible for the reproduction of flowers and food bearing crops. (Free J.B, 1993) Food production to a large extent will be compromised in the event of these natural pollinators fading away. A recent report from North America states that a disease called ‘Israeli acute paralysis’ viruses was responsible for the disappearance of a large percentage of honey bees in what was called ‘ Colony Collapse Disorder’ (CCD). The reasons were mainly attributed to the fact that the origins of the virus were contributed to by humans. (Kluser Stephane and Peduzzi Pascal, 2007) Decline of Pollinators Recent studies conducted in the UK and Netherlands as late as in 2006 suggests that there has been close to 70% reduction of insect pollination for a certain category of wild flowers. (Biesmeijer Jc et al, 2006) Part of the reason is that close to 3.4% of butterflies causing this pollination has become extinct with an equal decrease of 71% of butterfly species. (Warren M.S et al, 2001) Source: Free J.B, 1993, Effect of bees on food output. The other recorded significant event was that of the Colony Collapse Disorder in North America. In 2007 there was major decline of one third of the honey bee population which had a domino effect on the crop production. This is because a major portion of the food crops cultivated by farmers in North America relied on the pollination of bees, butterflies and flies. About 95 different types of food crops are being cross pollinated by these insects. (Morse R.A and Caldero ne N.W, 2000) Some of the factors that were attributed to this decline in North American bees included attack by parasites known as Varroa Destructor. Imports of African bees also lead to incompatibility issues. The unrestrained uses of pesticides in crops also lead to the death of these bees. (i) Symptom of CCD- Absence of adult bees in the hives was the primary symptom. The presence of a lot of immature bees along with abundance of food in the form of honey was also an indicator. The bee colonies started collapsing and sugar syrup that is fed as food was not being consumed. Further the task force was being limited to only young bees. (Kluser Stephane and Peduzzi Pascal, 2007) (ii) Causes of CCD (a) To overcome the attack from mites these beehives were being subjected to increased dosage of chemicals resulting in irreversible damage. (b) Pathogens like Paenibacillus Larvae and parasites had found their way into the bee ecosystem. (Kluser Stephane and Peduzzi Pascal, 2007) (c) The f itness levels of bees experienced major decline as was deduced by the release of stress proteins. (d) Use of Insecticides. (e) Theories have also suggested the radiations that were emitted by the towers engaged in mobile communication affect the bees in an adverse manner although this has not been substantiated

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