Sandy Hook’s campground, located in New Jersey’s portion of the Gateway National Recreation Area in Monmouth County, is closed until further notice due to an infestation of pests, officials said Friday. Reservations to secure camping spots at the popular National Recreation Area campground were closed online due to sightings of invasive pests in the area. Gateway officials called the response an “emergency,” but did not disclose what type of invasive species led to the closure. “This emergency closure is related to sightings of invasive pests at the campground and out of an abundance of cautio…