Over-Population of White-Tailed Deer Presents an Imminent Threat
to Block Island's Natural Resources
PROVIDENCE - The Department of Environmental Management today
filed emergency regulations establishing a non-recreational program to reduce
the over-population of Virginia white-tailed deer that currently presents an
imminent risk to the health, safety, and welfare of Block Island's natural
resources. DEM has determined that implementation of a
non-recreational deer reduction program is required in order to protect the
fragile habitats and unique natural communities found on Block Island.
The density of white-tailed deer on the 9.75 square mile Town of New Shoreham is estimated at 80-100 deer per square mile. This estimated population range was established by direct counts from an aerial sampling survey and is approximately eight to 10 times the desirable level for cultural tolerance and ecological health on Block Island. The Town of New Shoreham and its residents have raised concerns about crop and landscape damage caused by the excess deer population and impacts on the Island's ecosystem. Traditional management methods have been unsuccessful in reducing the Island's deer population.
Scientists at DEM's Division
of Fish and Wildlife and
The Nature Conservancy believe that the over-abundance of deer on Block Island
is also having long-term impacts on the Island's ecology. The Nature
Conservancy has documented negative effects of the white-tailed deer population
on the natural community types on Block Island. Block Island has a wealth of
unique species, including state and federally endangered/threatened species and
fragile habitats including globally-imperiled morainal grassland, that are at
risk from the over-abundance of deer.The density of white-tailed deer on the 9.75 square mile Town of New Shoreham is estimated at 80-100 deer per square mile. This estimated population range was established by direct counts from an aerial sampling survey and is approximately eight to 10 times the desirable level for cultural tolerance and ecological health on Block Island. The Town of New Shoreham and its residents have raised concerns about crop and landscape damage caused by the excess deer population and impacts on the Island's ecosystem. Traditional management methods have been unsuccessful in reducing the Island's deer population.
"The problems on Block Island are unique to the state," noted DEM Director Janet Coit. "The size of the deer population is substantially larger than that of any other community on the mainland, and is far beyond the capacity of the Island's ecosystem system to withstand the damaging effects. The excessive deer population has adversely impacted a number of threatened and endangered species and presents an imminent peril demanding the measures we are taking in this pilot program. These deer reduction techniques have been used effectively in other parts of the region and we look forward to obtaining similar results on Block Island."
One of the plants on the Island most affected is the state-endangered northern blazing star (found nowhere else in the state). Research conducted by The Nature Conservancy found that deer had grazed upon and consumed 97% of the Island's unfenced northern blazing star wildflowers, thereby preventing most of this species from going to seed and sustaining the population. In addition, the deer grazing on native plant species has caused a negative change in the habitat structure throughout Block Island. This has triggered a tremendous expansion of invasive plant species inedible to deer, such as mile-a-minute weed vine and black swallowwort. This fundamental change in the habitat structure - from a healthy shrub community to a tangle of vines has a potential negative effect on migratory birds, mammals, and butterflies.
DEM has worked closely with the RI Department of Health (HEALTH) to understand any public health issues the deer population may create. "There is some evidence that deer reduction will decrease the burden of tick-borne diseases," said Director of Health, Michael Fine, MD. "However, we don't expect to see that reduction until the deer population has been reduced by 80 or 90 percent. It is important for people to continue with personal protection measures to prevent tick bites." Prevention tips can be found on HEALTH's website atwww.health.ri.gov/diseases/lyme.
The regulations, which allow DEM to conduct a bait and shoot culling operation, take effect immediately. In the coming weeks DEM will be working with the Town to develop the process and the action plan for a multi-year deer reduction program that will likely begin early in 2014. The regulations are available on DEM's website at www.dem.ri.gov in the "Timely Topics" section on the right side of the homepage.