Abstract
Cane toads (Rhinella marina) were introduced worldwide and have become invasive in multiple locations, representing a major driver of biodiversity loss through competition (food, shelter, territory), predation, and the poisoning of native species. These toads have been used in Australia as a model for studies concerning invasion biology and ecoimmunology, as longer-established (core) and invasion front (edge) populations show altered stress and immune response profiles. Although cane toads were also introduced into the United States in the 1950s, these patterns have yet to be evaluated for the populations spanning Florida. Toads introduced into Florida have dispersed primarily northward along a latitudinal gradient, where they encounter cooler temperatures that may further impact stress and immune differences between core and edge populations. In this study, we sampled cane toads from nine different locations spanning their invasion in Florida. Cane toads from southern populations showed higher plasma bacterial killing ability and natural antibody titers than the toads from the northern populations, indicating they have a better immune surveillance system. Also, southern toads were more responsive to a novel stressor (1 hr restraint), showing a higher increase in corticosterone levels. These results indicate that possible trade-offs have occurred between immune and stress responses as these toads have become established in northern cooler areas in Florida.
| Original language | English |
|---|---|
| Pages (from-to) | 779-791 |
| Number of pages | 13 |
| Journal | Journal of Experimental Zoology Part A: Ecological and Integrative Physiology |
| Volume | 333 |
| Issue number | 10 |
| DOIs | |
| State | Published - Dec 1 2020 |
| Externally published | Yes |
Funding
We would like to thank Dr. Braz Titon Jr. (USP/Brazil) for the assistance with stats, Dr. Stefanny C. M. Titon (USP/Brazil), for brainstorming. We are also grateful to the reviewers that contributed to an improved version of the manuscript, with a more detailed methodology section and clearer and concise discussion. Animal handling and protocols were performed under Auburn University IACUC PRN (2017‐3106). This study was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) through BEPE scholarship (2017/04802‐5) for VRA ( http://www.fapesp.br ) and the Cellular and Molecular (CMB) Peak of Excellence Graduate Research Fellowship at Auburn University for STG. The funders were not involved with the study design, collection of specimens or analysis of data, the writing of the manuscript, or the decision to submit for publication. We would like to thank Dr. Braz Titon Jr. (USP/Brazil) for the assistance with stats, Dr. Stefanny C. M. Titon (USP/Brazil), for brainstorming. We are also grateful to the reviewers that contributed to an improved version of the manuscript, with a more detailed methodology section and clearer and concise discussion. Animal handling and protocols were performed under Auburn University IACUC PRN (2017-3106). This study was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) through BEPE scholarship (2017/04802-5) for VRA (http://www.fapesp.br) and the Cellular and Molecular (CMB) Peak of Excellence Graduate Research Fellowship at Auburn University for STG. The funders were not involved with the study design, collection of specimens or analysis of data, the writing of the manuscript, or the decision to submit for publication.
Keywords
- amphibian
- antibody titers
- bacterial killing ability
- corticosterone
- ecoimmunology
- range expansion
- restraint