Gut microbiome composition predicts summer core range size in two divergent ungulates

Area of Science:

• Ecology
• Microbiome Research
• Animal Movement Ecology

Background:

• Animal health is influenced by gut microbiome composition, which varies with diet, age, and habitat.
• Home range size in ungulates is linked to feeding strategies, fitness, and habitat use patterns.
• Ungulate species possess distinct gut microbiomes and spatial ecology.

Purpose of the Study:

• To investigate the relationship between gut microbiome composition and space use in a specialist (mountain goat) and a generalist (white-tailed deer) ungulate.
• To test the hypothesis that higher Firmicutes to Bacteroidetes ratios are associated with larger home ranges and that these relationships are more pronounced in habitat specialists.

Main Methods:

• GPS radiocollaring of 24 mountain goats and 34 white-tailed deer.
• Fecal sample collection for high-throughput 16S rRNA gene sequencing to analyze gut microbiome composition.
• Calculation of gut diversity metrics and bacterial ratios, including the Firmicutes to Bacteroidetes ratio.

Main Results:

• A positive correlation was found between the Firmicutes to Bacteroidetes ratio and core home range area in both mountain goats and white-tailed deer.
• Mountain goats displayed a negative relationship between gut microbial diversity and the use of forested areas and escape terrain.
• No significant relationships were detected between gut microbiome metrics and habitat use in white-tailed deer.

Conclusions:

• This study provides the first evidence linking home range size to the gut microbiome in wild ungulates.
• The findings suggest that gut microbiome composition plays a role in the spatial ecology of ungulates, particularly for habitat specialists.
• Non-invasive sampling methods, like fecal analysis, can yield valuable insights into the interplay between animal physiology and behavior.