Nothing beats a dog’s nose for detecting explosives. Unfortunately, there aren’t enough dogs:

Last month, the US Government Accountability Office (GAO) released a nearly 100-page report about working dogs and the need for federal agencies to better safeguard their health and wellness. The GOA says that as of February the US federal government had approximately 5,100 working dogs, including detection dogs, across three federal agencies. Another 420 dogs “served the federal government in 24 contractor-managed programs within eight departments and two independent agencies,” the GAO report says.

The report also underscores the demands placed on detection dogs and the potential for overwork if there aren’t enough dogs available. “Working dogs might need the strength to suddenly run fast, or to leap over a tall barrier, as well as the physical stamina to stand or walk all day,” the report says. “They might need to search over rubble or in difficult environmental conditions, such as extreme heat or cold, often wearing heavy body armor. They also might spend the day detecting specific scents among thousands of others, requiring intense mental concentration. Each function requires dogs to undergo specialized training.”

A decade and a half ago I was optimistic about bomb-sniffing bees and wasps, but nothing seems to have come of that.