Challenge: Granivores (seed eating animals) and herbivores can introduce challenges to restoration projects. Granivorous species (e.g. rodents, birds, insects) can be detrimental to seeding efforts by consuming large amounts of freshly applied seed. Harvester ants are particularly efficient at removing seed, and are often found in high numbers in arid and semi-arid environments ^[1]. Small mammals can also damage seedlings and saplings by direct herbivory and soil damage through burrowing.

Strategy: Seeds applied with binding or covering materials such as mulch or binders can limit access to seeds by seed eating animals. Installing chicken wire fencing or protecting saplings with plastic collard like Tubex Tree Shelters or biodegradable guards (e.g. rigid seedling protection tubes or Eco Gard) can limit access of herbivores restoration materials in the field. Installing (when appropriate) barn owl boxes or raptor perches in and around restoration sites (approximately 1 per acre) can reduce small mammal populations. Seeding less expensive but granivore-favored seed close to the target restoration seeding area has also shown utility in enhancing seedling establishment ^[2]. Seed traits (such as size and shape) should be considered when choosing plants for a restoration project. Seed structures (e.g. awns, pappus) and coatings can reduce seed predation by harvester ants, as they have been shown to prefer smaller seeds with no structure ^[3]. More labor intensive but perhaps more effective controls can include the use of zinc phosphide bait and mousetraps. Finally, in areas where herbivores are known to congregate, choose plants that are resistant to herbivory.

Resources

• Minimizing browsing damage by deer
• Deterring rodent seed-predation using seed-coating technologies
• Raptor perches for biological pest management
• Granivores and Restoration: Implications of Invasion and Considerations of Context-Dependent Seed Removal

References