Biomass in turtle populations: A neglected subject

Area of Science:

• Ecology
• Herpetology
• Vertebrate Biology

Background:

• Understanding vertebrate biomass is crucial for ecological assessments.
• Turtles represent a significant component of many ecosystems, yet their biomass is not well-characterized.
• Comparative biomass data across different vertebrate groups can reveal ecological patterns.

Purpose of the Study:

• To quantify and compare turtle biomass across various species and habitats.
• To investigate factors influencing turtle biomass, such as diet and habitat type.
• To compare turtle biomass and production with other vertebrate groups.

Main Methods:

• Field studies and literature reviews to gather biomass data for individual turtle species.
• Statistical analysis to compare biomass values across different dietary guilds (herbivorous, omnivorous, carnivorous) and habitat types (aquatic, semiaquatic, island, pond, spring).
• Estimation of annual production rates for selected turtle populations.

Main Results:

• Individual turtle species biomass can reach up to 586 kg/ha.
• Turtle biomass is generally an order of magnitude higher than endotherms but comparable to aquatic ectotherms.
• Herbivorous turtles showed a trend towards higher biomass, while semiaquatic species had the lowest.
• Islands, ponds, and springs supported the highest turtle biomass.
• Annual production estimates ranged from 1.4 to 14.9 kg/ha/yr, comparable to most vertebrates except fish.

Conclusions:

• Turtles can achieve substantial biomass, particularly in specific habitats and among herbivorous species.
• Habitat and diet are key factors influencing turtle biomass.
• Turtle biomass and production are significant ecological parameters, though generally lower than fish biomass.