Alligator Depredation

Currylow, Andrea F., Fitzgerald, Austin L., Goetz, Matthew T. H., Draxler, Jared L., Anderson, Gretchen E., McCollister, Matthew F., Romagosa, Christina M. & Yackel Adams, Amy A., 2023, Natives bite back: depredation and mortality of invasive juvenile Burmese pythons (Python bivittatus) in the Greater Everglades Ecosystem, Management of Biological Invasions 14 (1), pp. 107-122 : 111

Alligator Depredation (AD; n = 5)

Throughout the study, we confirmed five American alligator depredations on juvenile pythons. Depredation events were discovered on 10, 28, and 30 October 2021, 07 December 2021, and 11 February 2022. Each of the 5 juveniles were visually confirmed to be alive 4 to 16 days before we confirmed depredation. We tracked each telemetry signal to the location of each alligator across several consecutive visits and monitored the movements of transmitter signals with the alligators (occasionally using underwater photography; e.g., Figure 1 ). We estimated the sizes of four of these alligators to range 1.5–2 m, with one larger animal estimated to be 3 m in length. We continued to monitor the alligators following the depredation events, but none of the transmitters were ever detected expelled or recovered before expiration.

Figures

Figure 1. Photographic evidence and representation of some of the variety of confirmed and potential causes of mortality found for invasive Burmese pythons (Python bivittatus Kuhl, 1820) in the Greater Everglades Ecosystem in 2021 in Big Cypress National Preserve, Florida, USA. From left to right: American Alligator (Alligator mississippiensis Daudin, 1802) depredations, mesomammal depredations (felid prints in muddy substrate; e.g., bobcat, Lynx rufus Schreber, 1777), Florida cottonmouth (Agkistrodon conanti Gloyd, 1969) depredations, potential avian depredations, mishandling/misidentification of appropriate prey (e.g., large hispid cotton rat, Sigmodon hispidus Say and Ord, 1825). Images by U.S. Geological Survey.