Pennsylvania and New Jersey, which share the Delaware River as a border, also share something far less beneficial: potentially destructive invasive species.
On Tuesday, Pennsylvania officials urged residents to protect their livestock and pets after an invasive tick from Asia, which found its first U.S. home in New Jersey, was confirmed to have spread to the commonwealth.
New Jersey drew national attention earlier this year when it announced that an exotic Asian tick, Haemaphysalis longicornis, also known as the longhorned tick, was present in Hunterdon County. Since then, authorities said it likely got started as far back as 2013 and was found in four counties: Hunterdon, Union, Middlesex, and Mercer.
In other countries, the longhorned tick has been a threat to animals and people. That has not been the case so far in New Jersey, but experts are watching.
Now, tests by the National Veterinary Services Laboratory in Ames, Iowa, have confirmed the tick was found on a wild deer in Centre County, Pa.
The invasive pest is known to swarm animals and can cause anemia in livestock. The Pennsylvania Department of Agriculture said that the tick is "known to carry several diseases that infect hogs and cattle in Asia" but that no infectious pathogens have been associated with it so far in the United States.
The department said the tiny tick is easily confused with other tick species, such as the rabbit tick. It is marked by a distinctive horn pattern on its back that might not be visible to the naked eye. The female longhorned tick can reproduce asexually, producing up to 2,000 eggs after feeding on a host such as cattle, pets and other small mammals, birds, and humans.
"Even experts have difficulty distinguishing among tick species, so it is important to take precautions to protect pets, livestock, and family members from becoming a host for ticks of any kind," David Wolfgang, Pennsylvania's state veterinarian, urged. "Scientists don't yet know how this species will adapt to the North American climate and animal hosts, but we know it survived New Jersey's winter and has infested sheep and cattle in this region."
"The discovery of the longhorn tick is another reminder of the importance of tick prevention for Pennsylvanians," said state physician general Rachel Levine. "Ticks can be found in your own backyard, so it is essential to wear long sleeves and pants, and use insect repellent containing DEET to help keep you safe from ticks and the diseases they carry. It is also important to check yourself and your pets for ticks, as pets can bring ticks indoors."
The tick has also been confirmed in Arkansas, New York, West Virginia, and Virginia.
Wolfgang recommended that residents check animals regularly.
The tick isn't the only invasive species crossing state lines.
Earlier in July, the spotted lanternfly, a crop-munching invasive pest first discovered on U.S. soil in Berks County, was confirmed in New Jersey in the northwest corner of the state bordering the Delaware River.
The spotted lanternfly is native to China, India, Vietnam, and East Asia, and is already present in 13 Pennsylvania counties.