Research

Doctoral Research Summary

Background- Freshwater fishes are generally under-represented in science research, policy arenas, and within leading biodiversity prioritization schemes. An ideal example is the South American arapaima— a large and unique fish species that grows up to 3 m and 200 kg and breathes atmospheric air at regular intervals (Arantes et al., 2010). In spite of their endangered status (IUCN and CITIES), arapaima remain among the most sought-after food fishes in tropical South America.  Their populations have been depleted due to over-fishing and illegal harvesting.  Additionally, the floodplain forests where arapaima likely breed and reproduce during the flood season are increasingly degraded.  Fortunately, arapaima has become a target of management initiatives by fishermen’s groups, non-government organizations, and government sectors (Castello 2009).  However, a present-day lack of knowledge on their basic biology may compromise these efforts. 

Objective- My work aims to improve inland fish conservation and management by examining key aspects of arapaima migration, growth, reproduction, and diversity (both genetic and taxonomic).  The specific objectives of my work are to:
-Determine age structure, growth and mortality rates using size-frequency and scale-analysis data.
-Determine age-of-first-maturity by visual examination of gonad development state.
-Evaluate population genetic structure of arapaima using analyses of microsatellite markers and mitochondrial DNA. 
-Analyze arapaima taxonomy through simultaneous observations on molecular and morphological variation, and including study of archived museum specimens.
-Use telemetry studies to explore arapaima migration and evaluate protected area and management designs.
In the face of intense fishing pressures and habitat loss, I hope this work will contribute to the recovery and conservation of arapaima and forested floodplain habitat.