Just 300 lynx remain on the Iberian Peninsula in Spain. That makes the Iberian lynx (Lynx pardinus) Earth’s most threatened feline species, according to the WWF. To keep tabs on these cats, conservationists have found an unlikely ally in the bloodsucking assassin bug, Yao-Hua Law reports for Discover.
While 300 sounds low, it’s actually a significant increase from previous years. In 2004, only 64 cats remained in mountains of southern Spain. By 2012, conservation efforts helped to revive the population to 156 individuals. Though the growth is promising, the International Union for the Conservation of Nature still lists the species as endangered.
One conservation project, the Iberian Lynx Conservation Breeding Program, has raising wildcats in captivity and releasing them into their native habitats in Portugal and Spain since 2010. The goal is to bolster local populations and jump start growth, but newly breeding females can often lose their first litters, as Law notes.
To see if the program was actually working, they needed to give females a pregnancy test—no easy feat when in comes to a wild feline. Typically, researchers would trap cats, tranquilize them and draw blood for lab testing. That’s hard to manage and might unnecessarily stress the animals out. Another method can detect pregnancy hormones in poop and urine, but at the time, those weren’t really feasible for the Iberian lynx program.
Instead the conservation team turned to assassin bugs, or triatomines. These critters feed off animal blood, using a super thin proboscis organ to stick unsuspecting prey and suck their blood. The organ is thinner than a needle and collects more blood than your average syringe.
Researchers stuck assassin bugs in containers covered with mesh, so they were trapped inside but could still feed, explains Law. Then, they hid the containers in cork linings placed in lynx dens. The bugs feed on the cats, and researchers used syringes to extract blood from the bugs, and then tested that blood for the hormones the indicate pregnancy. And the cats are none the wiser.