Preserve Predatory Pests

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Here’s a Good Cause: Preserve Predatory Insects

  Top: Adult damsel bugs wait for insects such as aphids to approach. Middle: Big-eyed bugs eat eggs, mites, aphids, and other small insects. Bottom: Lady beetle larvae are colored black to dark purple with spots of orange.

Predatory insects contribute to natural pest control by eating unwanted pests and helping to maintain pest populations at non-damaging levels. By conserving and encouraging predator populations, plants can be protected from excessive damage.

A common group of beneficial insects are the generalist predators that feed on a wide variety of insect prey. Generalist predators capture and kill their prey immediately and eat many prey individuals during their development. Some of the most abundant generalist predators include damsel bugs, big-eyed bugs, and lady beetles. Each of these predators is found in many different habitats, from backyard gardens to large agricultural operations. These predators overwinter as adults, becoming active and producing eggs in spring.


Damsel bugs are slender, soft-bodied insects with long antennae and legs. A key characteristic of these predators is their enlarged front legs modified for grasping their prey (also known as raptorial legs), similar to a praying mantis. Damsel bugs use a sit-and-wait hunting strategy, capturing prey that comes within reach. They kill by inserting their piercingsucking mouthparts into their prey and sucking up the body contents.

Big-eyed bugs also have piercing-sucking mouthparts and feed in a similar way. Big-eyed bugs have large bulging eyes and excellent vision. Although they are very small predators (3/16-inch or less), they are very fast, active hunters that eat large numbers of prey. Their diet consists of small prey, like insect eggs, mites, aphids, and young larvae and nymphs, but they also feed on plants to sustain their populations. (Feeding on plants does not result in noticeable plant damage.) The advantage is that big-eyed bugs can remain in an area and feed on plants when prey are not abundant.

Lady beetles are perhaps one of the most recognizable predators. However, their eggs and voracious larvae are often overlooked. Lady beetles typically deposit their clutches of bright yellow eggs on the undersides of leaves. Larvae are active hunters that seek out their prey and kill with their chewing mouthparts. The larvae have very large appetites and can attack large prey. Unlike lady beetle adults which can fly, the larvae are wingless and are more likely to stick around an area with insect prey to complete their development.

Beneficial insects can be conserved by reducing broadspectrum pesticide use and selecting pesticides that are “soft” or selective and specifically target the pest. Predatory insects can be encouraged by providing them with alternative food resources and shelter. In general, diverse cropping systems and flowering plants may be a way to enhance predator activity. When sampling and monitoring pests it is important to also monitor predator populations and incorporate them into an integrated pest management program.

Look for fact sheets highlighting these and other beneficial insects in the near future.


-Ricardo Ramirez, Extension Entomologist