Plant nutrient concentrations inform white-tailed deer diet limitations

Area of Science:

• Wildlife ecology
• Nutritional ecology
• Rangeland management

Background:

• Nutritional carrying capacity (NCC) models are crucial for wildlife management, but can be inaccurate if they focus on a single nutrient.
• Herbivores have complex dietary needs, often requiring multiple nutrients simultaneously.
• Understanding nutrient limitations is key to effective management of large herbivores like white-tailed deer.

Purpose of the Study:

• To evaluate crude protein and phosphorus concentrations in forages for lactating white-tailed deer.
• To assess the adequacy of plant species in meeting dual nutrient constraints.
• To inform the development of more accurate NCC models.

Main Methods:

• Analyzed crude protein and phosphorus in 131 plant species consumed by white-tailed deer.
• Compared nutrient levels against minimum requirements for lactating females (14% crude protein, 0.3% phosphorus).
• Developed NCC models using both crude protein and phosphorus to identify the most limiting nutrient.

Main Results:

• Only 43.9% of forages met crude protein needs, and 18.8% met phosphorus needs.
• Young forb tissue had the highest average concentrations of both nutrients.
• Phosphorus was frequently the more limiting nutrient, though this varied by site.

Conclusions:

• NCC models must consider multiple, potentially co-limiting nutrients for accuracy.
• Providing a diverse range of plants, especially forbs, is essential for meeting simultaneous nutritional demands.
• Management strategies should focus on plant diversity to support herbivore populations effectively.