Property Damage

According to the Wildlife Society, Nationwide deer-vehicle accidents cause about 29,000 human injuries, 200 human fatalities, and $1 billion in property damage annually. Maryland sits firmly in the top 15 states for deer-vehicle collisions. This ranking is likely to increase given the areas population growth coupled with the increase in urban deer populations.

Montgomery County Reported Deer Vehicle Collisions *

*County believes the actual numbers are possibly 2-3 times the numbers shown above.

From 2011 to 2013 in Prince George’s County, there were 2101 carcasses picked up by Animal Control, mostly from county roads. During this same time, the Maryland State Highway Administration reported 914 carcasses removed from state highways. The County believes the true number of deer-vehicle collisions to be much higher because this data does not include unreported carcasses or deer that survive a vehicle collision. Click here to see the PG County Deer Vehicle Collision Map 2011-2013

While vehicle accidents involving deer occur all year round, the greatest likelihood of such collisions is after dark during November. This coincides with the height of the deer mating season.

Here are some driving tips to help prevent striking a deer with your vehicle:

• DRIVE THE SPEED LIMIT. Slower driving speeds give you and the deer more time to react.
• Deer are more active from dusk to dawn. Be cautious when driving during these times.
• The fall breeding season (October-December) has the highest occurrence of deer-vehicle collisions. Deer activity increases during the breeding season as male deer seek females to mate.
• Look for the eye shine of deer when driving at night.
• Pay attention to stretches of roads with deer crossing signs.
• Deer tend to travel in groups. If one deer is observed crossing the road, drive slowly and look for more deer.

Ecological Damage

Our forests are threatened by a perfect storm of problems – suburban sprawl, the impact of marauding invasive plants and insects, climate change, acid rain, decreasing rainfall, and increasingly intense weather patterns. Deer are contributing to these problems by overbrowsing young trees which kills replacement saplings, depletes shade and promotes the growth of invasive plants that smother native species. With each deer consuming approximately 10 pounds of vegetation every day, our forests cannot regenerate vegetation fast enough to support 100+ deer per square mile. This rate of consumption, coupled with very high deer densities is directly responsible for a loss of biodiversity of both plants and animals and threatens the stability of our natural areas.

Healthy Understory

Deer Browsed Understory

The forests in Maryland are no longer healthy given the absence of the understory and groundcover which has been almost completely removed by deer browsing. The absence of the understory affects the forest in three ways.

1. Forest Lifecycle:

In a healthy forest, understory is partially comprised of young tree shoots. These are the trees which should eventually replace the senior members of the woodland. If a large storm or hurricane topples the mature trees in a balanced woodland, there are young members of each species poised to close the canopy. However, in our overbrowsed forests there are almost no saplings available to replace the dead or damaged trees.

2. Birds and Animals:

Forest understory supports several bird species by providing nesting and food resources. When the understory is gone, so are the bird species. It is estimated that 5-7 songbird species can no longer be found in suburban Maryland due to deer browse impacts.

3. Plant Biodiversity:

The selective nature of deer browsing reduces species diversity of forests. Deer have significantly diminished the population of native species, such as young oaks through the consumption of acorns and seedlings which could lead to the complete loss of many heavily-browsed native species. Excessive browsing on native shrubs, especially in winter, has also provided greater opportunities for monocultures of non-native invasive plants like garlic mustard and japanese stiltgrass to establish themselves. Native wildflowers too have all but vanished from our forests in areas heavily browsed by deer.

Read more about the serious threat of deer overpopulation: Nature Conservancy – Too Many Deer: A Bigger Threat to Eastern Forests than Climate Change?

Lyme Disease

Lyme disease has increased dramatically in Maryland. In fact, since 1993, Maryland’s cases of Lyme disease reported to the Centers for Disease Control and Prevention (CDC) have increased by more than 650 percent! Maryland has one of the highest rates of Lyme disease in the United States. But many health care professionals believe that the actual number of cases far exceeds the reported figures.

How Lyme disease is spread to humans

Lyme disease, so named because the first case was reported in Lyme, Connecticut, is caused by bacteria transmitted by the bite of an infected black-legged tick, often carried by the white tailed deer. The tick must be attached to the skin for at least 24 hours for transmission to occur. It’s important to note, however, that not every tick bite causes Lyme disease. There is no vaccine currently available to prevent Lyme disease, so early detection and treatment are important.

Do ticks get their infections from deer?

Blacklegged (deer) ticks do not get infected with Lyme disease by feeding on deer. Instead, white-footed mice, other small rodents, and some birds carry the infections and pass them to ticks that feed on them. Deer are important, however. They are the main reproductive host for the adult stage of Blacklegged ticks. On average every deer, every year feeds enough adult deer ticks to allow those ticks to create an estimated 450,000 new, larval ticks.

Rule of thumb: no deer, likely no deer ticks. See deer, watch out, ticks may be present! Remember, deer typically are active at night, so even if you don’t see them on your property, they may still be visiting.

Methods to Manage the Herd

Due to the lack of natural predators and increase in favorable habitat for deer, their numbers must be reduced to bring the population in line with the ecological carrying capacity of the land:

Sharpshooting:

Often carried out by municipalities, sharpshooting is a generally effective method of population control. Government sanctioned sharpshooting can end up being expensive to taxpayers though – estimates range from $150-$500 per deer removed. Another major flaw is that sharpshooting can only be used in very limited circumstances because the high powered rifles favored by sharpshooters cannot be used in densely occupied areas.

Experimental sterilization and birth control:

Experimental sterilization and birth control programs are costly to taxpayers and have been shown to be ineffective. These methods have only shown to be effective on deer herds living in small fenced enclosures and the results could not be replicated in free ranging populations. Sterilization and birth control are also expensive (up to $2500 per animal), and require live capture which leads to a large percentage of deer being injured or killed.

Dosage control and ingestion of anti-fertility agents by non-target animals and humans as well as the potential negative impacts on deer genetics are also a concern. Recent reports have shown that some experimental drugs are resulting in high levels of ovarian tumors and other reproductive abnormalities and may these drugs may also be negatively affecting the animals group behavior.

To learn more click: Turning Deer Control Into a Science

Trap and Transfer:

Trap and transfer is not only labor intensive and expensive (costs average $250-550 per deer), but also has a high mortality rate after relocation – estimates range as high as 75-80%. There are also serious concerns that relocated deer may also spread disease.

Other control methods:

Other damage prevention alternatives for farmers and home owners include mechanical noise-producing devices, chemical repellents, and fencing.  The problem with each of these alternatives however is that do not fix the underlying problem – the overpopulation of the urban deer herd. Each of these options have pros and cons but most of these controls end up being ineffective in the long term.

Deer fencing can create a permanent barrier, but to be effective the fence must be at least 8ft tall and must be regularly inspected and repaired – deer are very adaptable and will use surprisingly small openings to enter a property in search of food. These deer fences are often cost prohibitive and many property owners find them aesthetically unacceptable.

Urban Bowhunting

While other population control options such as fencing, repellents, trap and transfer, fertility agents, sharp shooting, and controlled public shotgun hunts have been studied and restudied, bowhunting consistently proves to be the most cost efficient and effective option for deer management in suburban areas. Fencing is expensive; repellents require frequent applications and are less effective at high population densities. Trap and transfer is labor intensive and expensive, fertility agents are experimental, costly, impractical, and ineffective on the current population size. Sharpshooting programs are expensive and require larger contiguous tracts of land to ensure safety.

CAN MY LOCAL GOVERNMENT HELP?

The State of Maryland and local governments take the deer population problem very seriously, but due to the fact that much of the deer population is on private property, the expense of harvesting each deer, and because of safety concerns, they are limited in their ability to respond on a scale necessary to make a difference. The State and Montgomery County support using archery to remove deer from urban and suburban areas:

• • 2019 Montgomery County Deer Management Plan – Download the plan.
  • Maryland 2009-2018 Deer Management Plan – Download the plan.

• • Maryland Department of Natural Resources Lethal Deer Management Site – Read more.

• • Comprehensive Management Plan for White-tailed Deer in Montgomery County – Download the plan.

• • Due to the effectiveness of bowhunting in urban areas, Maryland recently amended the County safety laws to increase the areas that can be legally hunted in Montgomery County.  – Download the bill – HB 3-13.

• Montgomery County is piloting a program to allow private groups to intensely manage deer populations in county parks beyond the usual managed hunts – ACDMT is participating in this program