Foraging is exploring for natural food resources to ensure their energy requirements during their development and adult-life. Several factors like Learning, Genetics, Presence of predators, Parasitism etc. Foraging can be categorized into solitary foraging and group foraging.  Generally, it involves actively searching for suitable patches, and once there, for prey or for hosts. In addition, they are greatly important as an ecosystem service for biodiversity conservation. The foraging animal may act as pest, predator and pollinator.

More than 30 genera of animals comprising of hundreds of species of floral foragers provide pollination services for over three-quarters of the staple crop plants that feed humankind and for 90% of all flowering plants around the world.

The foraging insects act as pest, predator, pollinator, and some have an insignificant role. The majority of species of flowering plants rely on pollination by insects and their foraging behaviour is flexible and complex because an efficient collection of nectar or pollen is no simple matter. Hundreds of foraging insect species are known to assist in the pollination of different plants. It is estimated that about 80% of the commercial crops are pollinated by foraging insects. The main groups of foraging insects are the bees, wasps, butterflies, moths, flies, beetles and cockroaches.

All the cultivated plants have floral nectarines with good pollen rewards and have colourful flowers to attract insects. That is why a large number of insects is attracted to rewards which are available after the dehiscence of flowers and anthesis. When the concentration of the flowering plants was high the presence of flower-visiting insects, particularly pollen and nectar collecting insects, were high as well. Plant-pollinator mutualism is a key interaction in a terrestrial ecosystem

In Bangladesh, Bhuiya & Miah (1990); Tadauchi & Alam (1993); Hannan (2003, 2007) and
Mazumdar et al. (2010, 2011) contributed to the knowledge of flower-visiting insects in agricultural crops. Mazumdar et al., (2014) listed a total of 103 species of foraging insects belonging to 62 genera of 22 families under 3 orders, viz. Hymenoptera, Diptera and Lepidoptera. Among hymenopteran visitors the genera Apis, LasioglossumTrigona and Xylocopa were found to be not only dominated in number but also had a rapid tendency of visiting flowers. The genera MuscaChrysomya, Allograpta, Eristalis, Helophilus and Eumerus belonging to order Diptera and Parnara, Pelopidus, Delias, Eurema of the order Lepidoptera are ranked second and third most important groups respectively. The social bees were hardly seen to forage flowers except for Apis ceranaTrigona fuscobaltiata and Xylocopa irridipennis.

Hymenopteran species were mostly attracted to cucurbit and Papilionaceae plants. The choice of plants might be due to nectar than pollen reward. Again if the pollen was the choice then the floral structure or colour might have played to attractant. Probably the important activity of bees, in terms of benefit to human, is their pollination of natural or wild vegetation. As observed, bees visited flowers for collecting pollen and nectar, whereas the purposes of wasps were mostly for preying. Dipterans are now widely acknowledged and are becoming an essential component of modern services for many commercial crops. After proper management, these crops are putting additional commercial value. Lepidopterans visit flowers for collecting nectars. They carry pollen from flowers to flowers as well.

Several species especially wild bees show a decline in abundance, but some generalists seem to thrive well. Human interference in the ecosystem for want of biological resources as well as lack of understanding of foragers’ true value accelerates the decline of pollinators. To assess the contribution on the conservation of both flowering and flower-visiting animals particularly insects, along with to get maximum benefits for human being further research in this respect are necessary for Bangladesh.

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