Data/hora: 06/06/2024 16:55:45

Biblioteca(s): | Embrapa Pantanal.
Data corrente: | 17/07/2001
Data da última atualização: | 30/03/2017
Autoria: | PINHEIRO, M. S.; ANDREOTTI E SILVA, R.; SANTOS, S. A.
Afiliação: | EMBRAPA Clima Temperado (Pelotas, RS); EMBRAPA Gado de Corte (Campo Grande, MS); EMBRAPA Pantanal (Corumba, MS).
Título: | Observations on the thermal selection of the Pantanal caiman (Caiman crocodilus yacare) hatchlings (Crocodylia: Alligatoridae).
Ano de publicação: | 2001
Fonte/Imprenta: | Revista Brasileira de Biologia, v.61, n.2, p.323-327, 2001.
Idioma: | Inglês
Conteúdo: | Three options of water temperatures ina thermal gradient that changed from 22 to 35C were offered to Pantanal caiman (Caiman crocodylus yacare) hatchlings. Animals from two nests were submited to temperatures during 19 days (Nest 1 - 20 caimans caught in the nature hours after hatching), corresponding to 1 to 7 observations periods, and 13 days (Nest 2 - 20 animals obtained by artificial incubation) relative to observations period 8. Caiman remain fasting during experimental period. Hatchling were aloocated in a enclosure containing three styrofoam boxes (120 L) disposed side by side enclosed by wire netting and filled with water to the top. Thus, the animals were free to access the boxes, which temperatures were changed at the end of each observations period to avoid position effects. Air temperature was keep close to 22C by air conditioning and water temperature was controlled by thermostats. The trial was divided in three phases determined by elimination of the less frequented temperature and its substitution by another temperature. In a first phase of the experiment that contained 1, 2 and 3 observation periods, the thermostats were regulated to 22C (BoxD), 26C (BxC) and 32C (BxA). In phase 2 to 26C, 29.5C (BxB) and 32C, including 4,5 and periods. In the third phase that included 7 and 8 periods, the thermostats were adjusted to 29.5C, 32C and 35C (BxE). The number of caiman in each box was recoreded two to three times a day (8:00, 14:00 and 17:00) before pointed water temperature. Mean water temperatures (+- standard deviation) and respective caiman frequency means by box/temperature were: Phase 1 (BxD/22.3 +- 1.2C - 10.3%; BxC/27.0 +- 2.4C - 32.0% and BxA/31.2 +- 1.1C - 57.6%); Phase 2 (BxC/26.6 +- 2.8C - 13.3%; BxB/29.3 +- 2.2C - 27.7% and BxA/31.3 +- 1.2C - 59.0%) and Phase 3 (BxB/29.5 +- 3.6C - 23.7%; BxA/31.0 +- 2.2C - 31.9 and BxE/34.0 +- 2.2C - 44%). Observing that in the phases 1 and 2 the box with hottest water (CxA) was more frequented. In the phase 3, the difference between higher and smaller frequiency strained to 20.7% in relation to almost 46.5% in phases 1 and 2, indicating that water temperatures between 29.5 and 35C resulted in body temperatures more next to the comfort zone, in the experimental conditions.
Palavras-Chave: | Caiman crocodilus yacare; Hatchling; Preferencia termica; Recem-eclodido; Reptile; Temperatura da agua; Thermal selection.
Thesagro: | Jacaré; Réptil.
Thesaurus Nal: | Alligatoridae; Crocodylia; Pantanal; water temperature.
Categoria do assunto: | --
Registro original: | Embrapa Pantanal (CPAP)
Exemplares: | CPAP - (50233-1) - UPC - SP - PP - SP16265 -  - 16265 - DIS