Demography of Hexarthra jenkinae (de Beauchamp) (Rotifera) from ephemeral and permanent habitats of the shallow waterbody Lake Texcoco (Mexico)

• Published in: Hydrobiologia 2022-10, Vol.849 (17-18), p.4073-4085
• Main Authors: Nandini, S., Carmona-Ruiz, José Alberto, Sarma, S. S. S.
• Format: Article
• Language: English
• Subjects: Algae; Biomedical and Life Sciences; Cohorts; Demography; Ecology; Ecology of Shallow Lakes; Experiments; Food; Food availability; Food supply; Freshwater & Marine Ecology; Growth rate; Habitats; Hexarthra jenkinae; Lakes; Life history; Life Sciences; Neonates; Pools; Population dynamics; Population growth; Population studies; Rotifera; Saline environments; Salt lakes; Sodium bicarbonate; Sodium chloride; Survival; Tables (data); Zoology
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1007/s10750-021-04784-7

Life history strategies of rotifers vary in relation to their habitats. We compared the demography of Hexarthra jenkinae (de Beauchamp, 1932) from ephemeral pools and the large, permanent Nabor Carrillo Lake, both parts of the saline Lake Texcoco in Mexico. Population growth tests were conducted at salinities of 10, 12.5 and 15 g l −1 (1:1 ratio of NaCl and NaHCO 3 ), at 22 ± 1 °C with two algal food concentrations (0.25 × 10 6 and 1.0 × 10 6 cells ml −1 of Nannochloropsis oculata ). The population growth experiments were initiated with ten individuals per jar, whereas for the cohort life table study we used ten neonates. Observations were taken once (population growth) or twice (life table) a day; experiments continued until the populations declined or the last individual of each cohort in the life table study died. Survivorship and growth rates increased with increasing food availability. From the population growth studies, we found that the clone established from the ephemeral pools had higher growth rates (0.23–0.55 day −1 ) than those from the permanent lake (0.12–0.34 day −1 ). Growth rates were lower in the lifetable experiments than in the population growth studies. Our results are discussed in relation to habitat and life history strategies exhibited by rotifers in shallow saline waterbodies.