Effects of bioturbation by crabs of the genus Uca (Ocypodidae)

• Grant number: 12/00210-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2012
• End date: February 28, 2014
• Field of knowledge: Biological Sciences - Ecology
• Principal Investigator: Tânia Marcia Costa
• Grantee: Luís Felipe Natálio
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental do Litoral Paulista. São Vicente , SP, Brazil

Abstract

Crabs of the genus Uca, also known as fiddler crabs, are organisms typical of estuarine systems. The bioturbating effect of the activity of these crabs on the sediment results in several benefits to other organisms. The present project aims to assess the amount of organic matter transported by these animals during excavation and feeding periods. Two experiments will be conducted: 1) Laboratory experiment: Use of 24 terrariums with 8 cm of sediment (first 4 cm of sediment with organic matter content less than 2%, and the lower 4 cm with approximately 20% of organic matter). Specimens of U. leptodactylous, with a density equal to that of the field, will be added to the system and after 72 hours, sediment samples will be collected from each replica and treatment (treatment 1: samples of the burrows; treatment 2: samples from the side of burrows; and control) to be analyzed as for its organic content (drying and burning of organic matter). 2) Field experiment: selection of an area with a predominance of U. lecptodactyla species, being collected twice a month - one in spring tide and one in quadrature tide - over four months, 5 samples of 20 grams of each type of pellet. Samples of local sediment will also be collected for characterization of the organic matter content. The data obtained will be assessed for normality and equality of variances. Different tests will be applied if data are normal and homoscedastic or abnormal and heteroscedastic. Thus, the efficiency of these animals as bioturbators will be assessed, highlighting their role in structuring the habitat. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

NATALIO, LUIS F.; PARDO, JUAN C. F.; MACHADO, GLAUCO B. O.; FORTUNA, MONIQUE D.; GALLO, DEBORAH G.; COSTA, TANIA M.. Potential effect of fiddler crabs on organic matter distribution: A combined laboratory and field experimental approach. ESTUARINE COASTAL AND SHELF SCIENCE, v. 184, p. 158-165, JAN 5 2017. (12/00210-2, 10/01252-5, 10/09763-9, 11/23611-0)