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Abstract Small mammals such as mice and voles play a fundamental role in the ecosystem service of seed dispersal by caching seeds in small hoards that germinate under beneficial conditions. Pilferage is a critical step in this process in which animals steal seeds from other individuals' caches. Pilferers often recache stolen seeds, which are often pilfered by new individuals, who may recache again, and so on, potentially leading to compounded increased dispersal distance. However, little research has investigated intraspecific differences in pilfering frequency, despite its importance in better understanding the role of behavioural diversity in the valuable ecosystem service of seed dispersal.We conducted a field experiment in Maine (USA) investigating how intraspecific variation, including personality, influences pilferage effectiveness.Within the context of a long‐term capture‐mark‐recapture study, we measured the unique personality of 3311 individual small mammals of 10 species over a 7‐year period. For this experiment, we created artificial caches using eastern white pine (Pinus strobus) seeds monitored with trail cameras and buried antennas for individual identification.Of the 436 caches created, 83.5% were pilfered by 10 species, including deer mice ((Peromyscus maniculatus) and southern red‐backed voles (Myodes gapperi). We show how individuals differ in their ability to pilfer seeds and that these differences are driven by personality, body condition and sex. More exploratory deer mice and those with lower body condition were more likely to locate a cache, and female southern red‐backed voles were more likely than males to locate caches. Also, caches were more likely to be pilfered in areas of higher small mammal abundance.Because the risk of pilferage drives decisions concerning where an animal chooses to store seeds, pilferage pressure is thought to drive the evolution of food‐hoarding behaviour. Our study shows that pilferage ability varies between individuals, meaning that some individuals have a disproportionately strong influence on others' caching decisions and disproportionately contribute to compounded longer‐distance seed dispersal facilitated by pilferage. Our results add to a growing body of knowledge showing that the unique personalities of individual small mammals play a critical role in forest regeneration by impacting seed dispersal.
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Small mammal associations with habitat composition, configuration, and management in tallgrass prairies: a review
Abstract Tallgrass prairie is among the most threatened ecosystems but is often fragmented and surrounded by human‐modified landscapes. Small mammals are integral components of tallgrass prairies. However, little is known about how landscape composition, configuration, and management impact small mammals in tallgrass prairies.We conducted a systematic literature review to identify species‐specific and community associations with three broad topics: landscape composition, landscape configuration, and management practices.We identified 61 studies that assessed our variables of interest. We categorised the location, species assessed, variables monitored, and results by species and for the community.The majority of studies (64%) were conducted in two states, Illinois and Kansas. Deer mice (Peromyscus maniculatus), prairie voles (Microtus ochrogaster), and white‐footed mice (Peromyscus leucopus) showed specific associations with landscape variables, with deer mice preferring bare ground and recently burned plots, and prairie voles preferring thatch and negatively associated with prescribed fire. White‐footed mice were frequently associated with wooded areas.Small mammal biodiversity was positively associated with patchy habitats containing greater diversity in vegetative composition and management regime. Management and land composition were both relatively well studied for several species; habitat configuration was understudied.We identified significant gaps in our understanding of small mammal landscape ecology in tallgrass prairies. With tallgrass prairie restoration a growing trend in this region, a greater understanding of drivers of small mammal populations will be crucial to successful restoration efforts. Future research should focus on understudied areas and species, and examine how habitat heterogeneity impacts small mammal biodiversity.
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- Award ID(s):
- 2322603
- PAR ID:
- 10479794
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Mammal Review
- Volume:
- 54
- Issue:
- 2
- ISSN:
- 0305-1838
- Format(s):
- Medium: X Size: p. 178-192
- Size(s):
- p. 178-192
- Sponsoring Org:
- National Science Foundation
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