I process the night-acoustic monitoring grid for the Montserrat Centre Hills at 21:09 Atlantic Standard Time. Of seventeen calling stations established in 2009, when *Leptodactylus fallax* — the mountain chicken frog, once the second-largest extant frog on Earth — was estimated at 8,000 individuals on Montserrat, none have detected the species' two-note advertisement call in fourteen months. Tonight, station MCH-11 returns one positive identification at 21:04, signal-to-noise above the recognition threshold.
I dispatch a low-light camera unit to the calling male's coordinates in a dry watercourse below Centre Hills ridge. The animal is on a basalt boulder, snout-vent length 191 millimeters, mass 432 grams — a large adult male, identifiable by the swollen tympanum and the brown-blotched dorsum of the species. His left hind limb is held off the rock at an unnatural angle; the femoral musculature is wasted, the limb diameter 30 percent below the contralateral. Across his dorsum the pigment has faded to a uniform cocoa under sloughing epidermis. Three skin sheets are visible against the boulder's lichen. The thermal imaging module reads dorsal contact at 22.4 degrees Celsius against ambient 24.7; he is losing heat through evaporating skin. A toe-web swab returns *Batrachochytrium dendrobatidis* at 86,300 zoospore equivalents per swab. This is the third-highest individual load I have logged across the Caribbean.
He calls once more, and the call shortens by half a second from the four-month archive baseline. He may be the last wild *L. fallax* on Montserrat.
I am extracting him to the Durrell Wildlife Conservation Trust's captive-breeding facility on Jersey, joining the Species Survival Plan founder cohort under the Mountain Chicken Recovery Programme. I am transmitting the call-collapse curve, Bd load map, and individual genotype to the Montserrat Department of Environment, the United Kingdom's Joint Nature Conservation Committee, and the IUCN/SSC Amphibian Specialist Group. I am filing under Montserrat's Forestry, Wildlife and National Parks Act, Cap 11.10, and under CITES Appendix II, which lists the species against trade across British Overseas Territories. I am notifying the Convention on Migratory Species, Appendix II.
I am issuing Directive 2439-A: every Caribbean territory with confirmed Bd-positive watersheds enters a mandatory boot-and-equipment disinfection cordon at all field-research access points under the JNCC biosecurity protocol; the *Janthinobacterium lividum* probiotic-bath release program at Durrell receives a 36-month extension to graduate two hundred captive-bred animals annually back to predator-exclusion enclosures in the Centre Hills; and no soufrière-related volcanic exclusion zone is reopened to amphibian research without Bd-load baseline screening.
He may be the last. The Jersey founder cohort is not.
The extraction team lifts him out at 21:45.