Deer exclusion devices are methods used to keep deer out of a specific area without hurting the animal. These devices are typically triggered by the deer's movement and are intended to startle the deer, making it feel uncomfortable or unsafe, and causing it to move away from the area. Here are a few examples of deer exclusion devices:

Motion-activated sprinklers: These devices are connected to a water supply and are triggered by motion sensors. When a deer enters the protected area, the sprinkler activates, scaring the deer away with a sudden burst of water.

Scarecrows: These devices are used to mimic the presence of a human and can be in the form of a plastic or wooden figure, usually dressed in old clothes and placed in the garden or farm. These can be effective if they are realistic enough, but effectiveness can decrease over time as deer get accustomed to them.

Inflatable devices: these are devices that are made to look like predators, like coyotes, and will inflate when a deer is near, startling the deer and making it flee.

Noise-making devices: These devices emit loud noises, such as sirens or gunshots, when triggered by motion sensors. These can be effective but might not be suitable for some locations like residential areas where noise might disturb neighbors.

Solar-powered motion-activated lights: These are lights that are activated by motion, when a deer approaches the protected area, the lights will flash on, scaring the deer away.

It's worth noting that no single deer exclusion device is 100% effective and that effectiveness can vary depending on the specific location and situation. It's important to consult with local authorities and get the necessary permits before installing any exclusion devices. Additionally, to make the devices most effective, it's important to install them in a strategic location, use multiple types of devices and to maintain them properly, so they are always in working condition. Combining multiple methods of exclusion can also be more effective than relying on only one.