Macronutrient profiles of wetland plants consumed by the Hawaiian Moorhen (Gallinula chloropus sandvicensis)

Abstract

Understanding the nutritional quality of wildlife foods is important for management and conservation efforts. We report the gross energy and macronutrient content of 10 plant species consumed by endangered Hawaiian Moorhens (Gallinula chloropus sandvicensis) along with gross energy and macronutrient content of three plant species not known to be consumed by moorhen. We also report the same information for Urochloa mutica that is consumed when it is , 10 cm tall, but not when it is taller. We also compared macronutrient composition of plant species collected from sites with different soil moisture levels. Energy density, fat, ash, nitrogen, protein, carbohydrates, and fiber of these wetland plants were similar across soil moisture categories, but differed among plant species. We tested for rank consistency of nutrient values across species to determine if some were consistently high across measures, and we tested whether there were differences in energy and protein content between natives and non- natives, and between species consumed versus not eaten. Rank values of macronutrients were inconsistent across species, and we found no differences in energy or protein across groups of species. Information on Hawaiian Moorhen nutritional requirements and the species' ability to metabolize these different plants will help inform wetland managers.