Heloise Pavanato

Studying for Doctor of Philosophy

Area of study:
Quantitative ecology of marine mammals, distance sampling methods

Supervisor: Richard Barker—

Email: hpavanato@maths.otago.ac.nz  

Thesis

Title:

Development of integrated line transect models

Supervisor: Prof. Richard Barker and Dr. Matthew Schofield

Previous degrees: BSc in Oceanography (Universidade Federal do Rio Grande)

MSc in Biological Oceanography (Universidade Federal do Rio Grande)

Line transect surveys are widely used to estimate population size of cetaceans (whales and dolphins). The basic idea of the method is to measure perpendicular distances from the line transect to the animals to enable the fitting of a detection function that will then be used to estimate abundance. However, the method has some assumptions that are usually violated, such as animals are always available to be detected; animals are detected with probability = 1 in the transect line; transect lines are randomly placed in relation to animal's distribution. Although these issues were already dealt by some studies, there is a lack of integrated frameworks that allow the estimation of these components simultaneously. Thus, my PhD research consists of developing integrated models accounting for detection probability, availability bias, detection bias and non-random distributed individuals in a single framework. Our final goal is to assess trends of cetacean populations from parameters estimated by the integrated models.

Publication

• Heloise J. Pavanato, Gabriel Melo-Santos, Danielle S. Lima, Marcela Portocarrero-Aya, Mariana Paschoalini, Federico Mosquera, Fernando Trujillo, Rafael Meneses, Miriam Marmontel, Cláudio Maretti (2016). Risks of dam construction for South American river dolphins: a case study of the Tapajós River. Endangered Species Research, 31, 47-60.
• Pavanato, H., Silva, KG., Estima, SC., Monteiro, DS. and Kinas, PG. (2013). Occupancy dynamics of South American Sea-Lions in Brazilian Haul-outs. Brazilian Journal of Biology, 73:4, 855-862