For every sighting of a Burmese python in Florida's Everglades, there could be up to 1,000 that we do not see, according to the top scientist at conservation group the Everglades Foundation.
The huge numbers underline the challenge facing conservation workers in controlling the fast-expanding population of the invasive species in the tropical wetlands of the Everglades, an ideal habitat for the snakes.
Steve Davis, the Everglades Foundation's chief science officer, told Newsweek that the Florida Python Challenge, an annual event that awards hunters with cash prizes for catching the most and the biggest pythons, is a good way to keep numbers down.
"The detection capacity for pythons is very low. I've seen estimates of 100 to 1,000 other pythons for every one python we see—1,000 being the extreme high end.
"That range may have changed as efforts like the python challenge help to improve our understanding of where they are and how to find them," Davis said.
Burmese pythons, which are native to southeast Asia, became an invasive species in the Everglades after being brought over as pets in the 1990s. Because they have no predators in the U.S. and can produce clutches of up to 100 eggs, python numbers have exploded across the Everglades. There are thought to be over 100,000 in the state of Florida.

In January 2012, the U.S. Fish and Wildlife Service banned the importation of four species of pythons, including the Burmese python. However officials admit that they should have acted much sooner.
"People might argue the ultimate boundaries, but there's no part of this state that you can point at and say that pythons couldn't live here," Frank Mazzotti, an associate professor of wildlife ecology in the University of Florida's Institute of Food and Agricultural Sciences, said in a 2012 news release. "They're capable of surviving anywhere in Florida, they're capable of incredible movement—and in a relatively short period."
This year's Florida Python Challenge, being held from August 5 to 14, was announced on June 16 by Governor Ron DeSantis, who said the pythons "wreak havoc on the ecosystem".
At a press conference about the 2022 hunt, he said: "We've worked hard on conserving Florida's natural resources and to make sure that we were taking a unique piece of property that God has given us and leaving it to the next generation better than we found it."
Burmese pythons outcompete native wildlife for food, which has led to enormous drops in the populations of native mammals, including raccoons and opossums.
The Florida Python Challenge is one attempt by the Florida government to eradicate at least some of the invasive populations. Burmese pythons, however, blend in extremely well with the marshy environment of the Everglades, meaning that they are difficult for hunters to detect.
The Florida Fish and Wildlife Conservation Commission (FWC) encourages people to kill Burmese pythons on private land, so long as it is done humanely. The FWC also runs a detector dog team, which goes out five days a week to hunt down pythons.
But these methods have done little to reduce the python population in Florida. In November last year, it was reported Burmese pythons had expanded their range north, with sightings in the Arthur R. Marshall Loxahatchee National Wildlife Refuge.
Burmese pythons use constriction to kill their prey, such as mice and birds, squeezing the animal until it suffocates. It is rare for a Burmese python to attack a human without being provoked, although there have been cases of captive Burmese pythons killing people in the U.S.
The Florida Python Challenge involves participants killing as many pythons as possible, with cash prizes for those who catch the most, and longest, snakes. The catcher of the most snakes wins $2,500, and the longest snake gets a $1,500 prize.
The Python Challenge suggests using captive bolt stunners or air guns to kill pythons. The use of firearms is prohibited during the 2022 competition.
The snakes must be killed humanely, or a participant will be disqualified. The FWC defines a humane killing as one resulting in the python losing consciousness immediately, followed by destroying its brain by 'pithing': inserting a metal rod into the brain and moving it around to completely destroy the tissue.
Attendees are taught how to correctly kill the pythons humanely as part of an online training course that is mandatory to enter the competition. Last year over 600 people registered to participate and 223 snakes were removed from the Everglades.