Distribution, habitat, and home range of São Paulo marsh antwren (Formicivora paludicola)

Author(s)

Glaucia Cristina Del Rio

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2014-05-05

Examining board members

Luis Fábio Silveira; Natália Mundim Tôrres; Leonardo Liberali Wedekin

• Advisor: Luis Fábio Silveira

Abstract

Wetlands in Upper Tietê and Upper Paraíba do Sul basins, in southeastern Atlantic Forest, Brazil, have been severely transformed by urbanization, agriculture and mining in the last 500 years. Endemic to these areas, the São Paulo Marsh Antwren (Formicivora paludicola) persisted through this period unknown to science until its discovery in 2005, when its threatened situation became worrying. This bird (Thamnophilidae) was discovered on the verge of extinction, and virtually nothing is known about its natural history, population structure and habitat selection, which made conservation perspectives pessimist and discredited. We investigated both the species distribution and the distribution of its suitable areas using ecological niche modeling, fieldwork surveys and occupancy models. Our results show that the species should be considered \"Critically Endangered\" according to IUCN criteria. Human occupation has resulted in a loss of more than 300 km2 of suitable habitat, so that it now occupies a total and severely fragmented area of only 1.42 km2. Additionally, F. paludicola has limited dispersal ability, narrow habitat specificity, and restricted habitat availability. Furthermore, we showed that marshes with lower cattail (Typha dominguensis) densities have higher probabilities of being occupied. Thus, these areas should be prioritized in future conservation efforts. Using Kernel home range estimations, we show that the species has a small home range of about 0.55 ha, and occurs in high densities in those areas where it is still present, with a total population size between 383 and 985 mature birds. Furthermore, using a novel tool for animal habitat selection studies, the Torus Shift, we showed that the alien invasive ginger lily (Hedychium coronarium) is avoided by the species, and that this invasion represents a serious threat to the remaining populations. The successful conservation of F. plaudicola rests on the creation of a series of interconnected protected areas, with natural and restored wetlands. Given the high density of their population structure, this species could thrive in a relatively small area of suitable wetlands protected from human occupation, water contamination and invasive plants. Such efforts would also greatly contribute to the general conservation and restoration of Atlantic Forest wetlands (AU)

• FAPESP's process: 11/16251-7 - Distribution, habitat and territory size of the sao-paulo-marsh-antwren (Formicivora sp. nov.)
• Grantee: Glaucia Cristina Del Rio
• Support Opportunities: Scholarships in Brazil - Master