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Promoting regeneration of native trees, likeQuercusspp., is a priority for land managers given the ecological and economic importance of oak woodlands. Although direct seeding may promote recruitment ofQuercusspp., the effectiveness of direct seeding may be greatly reduced in environments where the activity of granivorous rodents is high. Importantly, the activity of granivorous rodents may be highest in environments where oak restoration is most desired, such as habitats invaded by non‐native woody shrubs. Implementing chemical deterrents to granivory should promote direct seeding success; yet it is essential to understand if those deterrents are effective in challenging restoration situations (e.g. areas with dense invasive shrub cover). Moreover, it is important to determine whether chemicals that deter granivory have undesired effects on beneficial ecological interactions, such as animal‐mediated seed dispersal. We used multi‐field site experiments in shrub‐invaded and shrub‐cleared forest plots to compare the removal and dispersal ofQuercus rubraacorns with seed coats treated with a pepper‐based capsaicin extract versus acorns treated with control solutions (i.e. water and ethanol). Seed removal was quantified for 37 days, and seed survival and dispersal were quantified by relocating nail‐tagged acorns after 8 weeks. We found that capsaicin‐treated seeds had a significantly higher probability of survival compared to seeds treated with control solutions; the presence of the invasive shrubRhamnus catharticaincreased post‐dispersal seed consumption regardless of seed‐coat treatment; capsaicin did not affect acorn dispersal distance; and the concentration of capsaicin coatings on acorns declined over time in the field. 

The utility of seed addition to promote tree regeneration can be greatly limited by animals that consume seeds. Moreover, given that restoration often occurs in forests where invasive shrubs are abundant, and evidence that invasive shrubs can increase granivory, it is important to explore whether methods for reducing granivory work equally well in invaded and uninvaded habitats. We used a multi-site field experiment spanning 160 days to explore whether coating seeds of Prunus serotina with capsaicin extract leads to reduced granivory in habitats with or without invasive shrubs ( Rhamnus cathartica). Capsaicin-coated seeds were removed at a similar rate to uncoated seeds, but seeds in invaded plots had a 78.8% higher rate of removal compared to plots without invasive shrubs. Our findings suggest that managers seeking to encourage regeneration of native trees using direct seeding should consider invasive shrub removal as a top priority to limit the loss of seeds once sown. 

Native legumes are functionally important members of grasslands, but their reintroduction into degraded systems is limited by strong establishment filters. One of these establishment filters might be rhizobia limitation, where legume seedlings are unable to find suitable rhizobia symbionts in grasslands targeted for restoration. To test links between rhizobial inoculation and legume demographic parameters in a grassland restoration context, we evaluated how inoculation with rhizobia altered survival and seed production of a native annual legume (Chamaecrista fasciculata) inoculated with rhizobia and transplanted into a restored prairie. Small mammal herbivory was an important filter affecting survival ofC. fasciculatatransplants, with inoculated plants 81% more likely to be grazed than uninoculated plants. Despite this heavy grazing, plants inoculated with rhizobia survived transplantation 71% more often and, as a result, produced 82% more flowers, experienced 73% more visits by pollinators, and on average produced 220% more seeds. Our results indicate that although herbivory may also shape legume population establishment, at least in some years in some places, rhizobia could alterC. fasciculatainteractions with both herbivores and pollinators and improve population establishment. 

Abstract Sin Nombre virus (SNV) is a zoonotic virus that is highly pathogenic to humans. The deer mouse,Peromyscus maniculatus, is the primary host of SNV, and SNV prevalence inP. maniculatusis an important indicator of human disease risk. Because the California Channel Islands contain permanent human settlements, receive hundreds of thousands of visitors each year, and can have extremely high densities ofP. maniculatus, surveillance for SNV in islandP. maniculatusis important for understanding the human risk of zoonotic disease. Despite the importance of surveillance on these heavily utilized islands, SNV prevalence (i.e. the proportion ofP. maniculatusthat test positive to antibodies to SNV) has not been examined in the last 13–27 years. We present data on 1,610 mice sampled for four consecutive years (2014–2017) on five of the California Channel Islands: East Anacapa, Santa Barbara, Santa Catalina, San Nicolas, and San Clemente. Despite historical data indicating SNV‐positive mice on San Clemente and Santa Catalina, we detected no SNV‐positive mice on these islands, suggesting very low prevalence or possible loss of SNV. Islands historically free of SNV (East Anacapa, Santa Barbara, and San Nicolas) remained free of SNV, suggesting that rates of pathogen introduction from other islands and/or the mainland are low. Although continued surveillance is warranted to determine whether SNV establishes on these islands, our work helps inform current human disease risk in these locations and suggests that SNV prevalence on these islands is currently very low.