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Body condition is used as an indicator of the degree of body fat in an animal but evidence of its actual relationship with health diagnostics (e.g., blood parameters) is usually lacking across species. In American alligators (Alligator mississippiensis), body condition has been used as a performance metric within the Greater Everglades ecosystem to provide insight on hydrological and landscape changes on alligator populations. However, there is no clear evidence that spatial body condition changes relate to different health conditions (low food intake vs sickness) and whether this link can be made when relating body condition values with blood parameters. We assessed the relationship between alligator body condition and 36 hematological and biochemistry (blood) parameters in four areas across two physiographic regions (Everglades and Big Cypress) of the Greater Everglades (sample size = 120). We found very strong to weak evidence of linearity between 7 (Big Cypress) and 19 (Everglades) blood parameters and relative condition factor index, from which cholesterol (38%) and uric acid (41%) for the former and phosphorus (up to 52%) and cholesterol (up to 45%) for the latter (mean absolute error MAE = 0.18 each) were the predictors that individually explain most of the body condition variation. The best combination of blood parameters for the Everglades were cholesterol, phosphorus, osmolality, total protein, albumin, alpha 2, beta, and gamma globulins, and corticosterone accounting for 40% (37 ± 21%, MAE = 0.16) of the variation found in alligator body condition for this region. We found better predictability power in models when analyzed at smaller rather than larger scales showing a potential habitat effect on the body condition—blood parameters relationship. Overall, Everglades alligators in poorer condition are likely dehydrated or have an inadequate diet and the spatial differences found between physiographic regions suggest that these areas differ in prey availability/quality. [ABSTRACT FROM AUTHOR]

Spectacled caimans (Caiman crocodilus Linnaeus, 1758) are established invaders in the United States, Cuba, and San Andres Island, Colombia. They have been established in South Florida since the 1970s and are found primarily within Comprehensive Everglades Restoration Plan (CERP) projects. These projects provide suitable habitat and may provide dispersal pathways via water management activities. Caiman presence in these areas directly conflicts with the CERP’s goals, and as a generalist species with a broad diet, they can impact biological resources. Past removal efforts failed to extirpate caimans, but their efficacy has not been well evaluated. We addressed caimans via removal surveys during 2012–2021 with the goal of evaluating extirpation or maximum species control within South Florida’s CERP projects. Documented opportunistic removals for this study began in December 2012, and systematic efforts have been ongoing since October 2017. We evaluated efficacy of caiman removals by analyzing 10 years of opportunistic and systematic survey data, plus associated removal data, along 11 survey routes during 2012–2021. We also conducted necropsies to collect biological information which could be used to improve removal efforts. We removed 251 caimans during 2012 to 2021, and the rate of caiman removals per year increased from 5 animals during 2012 to a peak of 47 animals during 2020. Necropsies revealed reproductive information (nesting/hatching timelines) that we applied to improve our removal rates. Caiman encounter rates declined from a peak of 1.55 ± 0.66 caiman/hr and 0.72 ± 0.38 caiman/km during 2013 to a low of 0.18 ± 0.09 caiman/hr and 0.03 ± 0.02 caiman/km during 2020 and slightly increased during 2020–2021, likely because of a change in search effort. We evaluated and discussed the potential for extirpating caiman from CERP projects and provide a data-driven prescription for removal efforts. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "How to estimate body condition in large lizards? Argentine black and white tegu (Salvator merianae, Duméril and Bibron, 1839) as a case study" published in the journal PLoS ONE. The correction addresses two errors in the article. The first error is in reference 50, which is corrected to McEachern et al. (2015). The second error is in Figure 2, where the symbol "<" should have been ">" in the third equation. The corrected equation is provided in the correction notice. The article was authored by Kelly R. McCaffrey, Sergio A. Balaguera-Reina, Bryan G. Falk, Emily V. Gati, Jenna M. Cole, and Frank J. Mazzotti. [Extracted from the article]