The importance of bio-pests

Humans used to be hunters and gatherers for 2.5m years, they plucked wild fruits and hunted wild animals as they traveled. It all changed about 10,000 years ago, when they started to influence the lives of selected wild plant and animal species for their benefit. The transition from nomadic to agriculture proceeded in a stage which involved just a small change in daily life over a generation.

What changes?

Presently, agriculture is one of the main occupations in the course of human civilization, which is the origin of the first crop to the society known today. In the long run, people started living together for agriculture practices. Availability of enough food and protection in a society helps in further population growth within the community. Use of pesticides and chemical fertilizers lead to maximum crop production, which helped in reducing hunger but this manipulation altered the whole ecosystems, resulting in habitat destruction, decline in biodiversity, soil fertility and nutrient depletion.

As the human population is increasing, demand for food is also increasing and intensive methods of farming eventually are escalating. This results in decrease of useful crop pest predators and thus rise in pest outbreaks. These intensive modern agriculture practices lead to deterioration of the natural habitat and biodiversity of numerous plants and animals. The use of pesticides kills the keystone species, which agitate the ecosystem and risk millions of important species up the food chain.

Chemical pesticides have been used as a traditional method for pest and disease control. However, it impacts negatively on biodiversity, crop quality and human health. Alternatively, use of biological pest regulation instead of pesticides is the best solution in recent scenarios.

Biological pest regulation maintains its population under the limit over time. Until now, biological pest regulation mainly focuses on manipulating the behavior of pests and arthropods (natural predator). Approaches like using pheromones (chemical signals that insects release to communicate), disrupt their mating and changing foraging sites have shown success. However, arthropods as a predator, mobility is not so much, indicating this method is effective in specific areas only where these predators are present. While arthropods as predators are effective bioregulators, including specific species of reptiles and amphibians into this approach can improve the regulation of pest populations. Utilizing arthropods, along with reptiles and amphibians significantly helps in bioregulation of pests.

Amphibians and reptiles can survive in a disturbed habitat and use different resources. While hunting, predators consider the characteristics of the prey, such as what they eat, how they move and how they behave in their environment. These characteristics reflect how predators prefer to hunt. For example: some actively search while others wait and ambush their prey.

Reptiles and amphibians use their visual and olfaction (sense of smell) to track and identify prey. The characteristic hunting process directs the sensory faculty either visual or olfactory. For example, lizards and some of the amphibians that are active foragers use their smell sensory while ambush foragers like some species of iguanas depend on their visual. In specific cases like oriental garden lizards, they wait for prey to come close, wait for the movement of the prey to capture. They don’t react if the prey doesn’t show any movement or release any chemicals by the prey.

According to foraging theory, active foragers prefer stationary prey having relatively large size and are widely distributed over area whereas ambush foragers catch mobile prey and prefer small size prey found in grouped distribution. Ambush foragers have broader prey as a diet than active foragers because the chance of capturing prey is less and they cannot be selective as active foragers.

Another interesting behavior of reptiles and amphibians is that they use the surrounding environment as information about the prey and protection from their predators. They can create a cognitive map (mental representation of the environmental reminder), which helps to guide in their home range, locating their spread-out prey without searching randomly every time.       

Active foragers are good at spatial learning since they have larger home ranges and are always in mobility, which require these skills more than ambush predators. While ambush predators spend less energy in searching for prey, they eventually change spots with abundances of food.

This information can help in the agricultural field, to mobilize active or ambush predators according to the nature of the pest, and the size of the agriculture farm.

Conclusion

Agriculture fields with active foragers are beneficial as they are good at scanning their environment and forming memories about pest-infested crops/areas. For them, spatial clues like natural habitats, trees help in locating prey more successfully. Meanwhile, ambush foragers use local cues like distinct shapes or natural rocks to find and remember hunting spots. Keeping crop patches in the same locations helps both active and ambush foragers to create authentic memories of their surroundings, making them easier to hunt.

Protecting and maintaining their habitats for breeding and hibernation is also important. Amphibians prefer small water bodies with warm and sunny aspects while reptiles favor open areas for warmth and vegetated areas for dwelling. Their habitats should connect so that the population gets easy access to each other for biological activities.  Maintaining habitat with dense vegetation for shelter, creating edges with different vegetations to add up habitat diversity, and maintaining different height shrubs will provide camouflage during different activities.