| Autor: |
Guarino FM; Department of Biology, University of Naples Federico II, Via Cinthia 26, I-80126 Naples, Italy., Andreone F; Museo Regionale di Scienze Naturali, Via G. Giolitti, 36, I-10123 Torino, Italy., Mezzasalma M; Department of Biology, Ecology and Earth Science (DiBEST)-University of Calabria, Via P. Bucci 4/B, I-87036 Rende, Italy., Licata F; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal.; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal.; Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal., Puoti S; Department of Biology, University of Naples Federico II, Via Cinthia 26, I-80126 Naples, Italy., Santos B; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal.; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal., Cocca W; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal.; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal.; Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal., Solofoniaina Fidy JF; Madagascar Fauna and Flora Group, BP 442, Toamasina 501, Madagascar., Ndriantsoa SH; Département de Biologie Animale, Université d'Antananarivo, BP 906, Antananarivo 101, Madagascar., Noel J; Madagascar Fauna and Flora Group, BP 442, Toamasina 501, Madagascar., Rakotonanahary TF; Turtle Survival Alliance, BP 8511, Antananarivo 101, Madagascar., Harison RF; Institut Supérieur de Science, Environnement et Développement Durable (ISSEDD), Université de Toamasina, Toamasina 501, Madagascar., Odierna G; Department of Biology, University of Naples Federico II, Via Cinthia 26, I-80126 Naples, Italy., Crottini A; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal.; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal.; Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal. |
| Abstrakt: |
We analyzed the body length, age structure, and age at sexual maturity of the invasive Asian common toad Duttaphrynus melanostictus from different sites in Toamasina, east Madagascar. We used skeletochronology as a proxy for age estimation, while gonads were histologically analyzed to determine the age of sexual maturity. The analysis of pooled age data from three sites investigated in 2016 showed that both sexes were larger, although not older, than those of native populations. For the individuals from Madagascar, the males were significantly smaller and younger (mean ± SD, SVL: 71.4 ± 1.6 mm; age: 1.8 ± 0.7 years) than the females (SVL: 78.42 ± 1.9 mm; age: 2.7 ± 1.3 years), when the data were pooled, but when the data were analyzed separately for each of the three sites, similar results were obtained only for one site. The oldest recorded male and female were 3 and 6 years old, respectively. Gonadal histology showed that the males and females reach sexual maturity after the first and second years of age, respectively. Further studies are needed to understand if the larger size and faster growth rates observed in the invasive population of D. melanostictus in Madagascar are a consequence of more favorable environmental conditions with respect to the native range (e.g., the availability of larger trophic niches, a lack of competitors, and lower predatory pressure), and we suggest to extend the monitoring of these life history traits to understand how they might influence the invasion. |
