THE NORTH ETIWANDA PRESERVE IS NOT A PLACE FOR DOGS!!! Hikers sometimes like to be accompanied by their dog, as they provide companionship and a sense of safety when in the wild.  Unfortunately, the dog and pet owner can cause unintentional consequences while hiking together in highly sensitive or controlled habitat preservation areas.  The North Etiwanda Preserve’s NO DOGS POLICY is meant to protect the natural balance of life found within its plant and animal communities.  Dogs as well as other artificially introduced intruders can affect this unique balance of life.   The information below should help you understand why pets should be left at home when a trip to the Preserve is planned.

Threat of Predation
Dogs are born with an instinctual nature to hunt, occasionally resulting in the injury or killing wildlife as well as displacement of endangered animals causing them to abandone thier home or nest.  This poses a significant level of threat to the survival of endangered species needing new hatchlings or newborns to carry on thier lineage and avoid extinction.   In addition to predation, dogs have a direct impact on vegetation when they engage in chasing wildlife off of the trail.  They often trample and dig while in pursuit, which can cause a removal of vegetation and ultimately habitat lost over time.

Though dogs are often unsuccessful in catching their prey, there is an indirect threat of predation involved when animals must expend exuberant amounts of energy to escape.  Many species on the preserve are often competing for scarce resources, leaving them with little energy to waste.  This has been seen to be the case most often in newborns and pregnant animals in the wild that lack the energy reserves to repeatedly avoid predators.

The spread of viral infections can occur just as quickly in the wild as it does in the human population.  In many cases dogs may be carrying a disease or parasite without exhibitiing any outward signs.  As host carriers for these ailments; dogs can have devastating effects to native species that lack immunity and access to medical care.  Many of these pathogens are often transmitted through the presence of dog feces found along the trails. Here are a few examples of some of the common pathogens dogs spread to wildlife:

Introduction of Non-Native Species
Dogs have the ability to affect the growth of the vegetation in the Preserve in two main ways, through seed and nitrogen introduction.  Many of the seeds of non-native species that are introduced to the preserve are carried in by both humans and animals.  Dogs generally have a greater chance of doing so, given that they come in closer contact with exotic plant material found in yards and can easily carry seeds in their fur.  The other way dogs affect the growth of non-native species is through their excrements.  Both forms contain concentrated amounts of nitrogen, which can both encourage the growth of non-native plants more readily and potentially supress or injure a native plants growth. Non-native species introduction is one of the greatest threats to changing the overall dynamic of a habitat, as invasive non native plants are often able to out-compete native plants.  The loss of native plant material can also result in the lost of species diversity.

Natural Resource Competition
The North Etiwanda Preserve can be a place that has limited resources for wildlife during certain times of the year.  Available water is one of the most limited resources found here, which can often be problematic if dogs are leaving the trails and depleting sources depended upon by native inhabitants.  The hightened competition for any of the limited resources can result in further disturbance of the native populations.


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Miller, J.E. and B.D. Leopold. 1992. Population influences: predators. Pp 119–128. in Dickson, J.G., editor. ed. The Wild Turkey: Biology and Management. Stackpole Books. Mechanicsburg, Pa