Revealing the Intricate Interplay Between Mice and Century-Blooming Plants

A team from Nagoya University in Japan, including Hanami Suzuki and Professor Hisashi Kajimura, has made significant discoveries about the interactions between mast-seeding plants like sasa bamboo and field mice. This research demonstrates how variations in mice species, environmental conditions, and seasonal changes significantly influence seed dispersal, thereby impacting forest ecosystem dynamics. This contradicts previous assumptions about seed storage and consumption behaviors in mice. Credit goes to Reiko Matsushita for this finding.

Insights into the Dynamics Between Mast-Seeding Plants and Seed-Consuming Animals

Focusing on sasa bamboo, a plant that blooms once every hundred years in central Japan, Suzuki and Kajimura’s study examined how field mice interact with the plant’s seeds. They discovered that the feeding patterns of different mouse species (the large Japanese field mouse Apodemus speciosus and the small Japanese field mouse A. argenteus), coupled with the presence of understory vegetation and the type of forest trees (broadleaf or coniferous), varied across seasons (summer or fall). This study overturns previous beliefs about mice’s seed storage habits and emphasizes the need to consider both plant and animal requirements for maintaining healthy ecosystems.

Masting in Dwarf Bamboo

Dwarf bamboo, or Sasa borealis, displays masting behavior, which involves synchronized flowering and seeding at intervals that can reach up to 120 years. These rare masting events result in a sudden abundance of seeds, providing a rich food source for various animals, particularly rodents like field mice.

Field Mice Behavior During Masting Events: An Experimental Approach

To gain deeper insights into field mice behavior during these masting events, the researchers simulated mass flowering and seeding using shallow mesh baskets filled with seeds. They then employed automatic cameras to observe the mice’s foraging behavior across different forest environments and seasons.

‘Removal and Caching’ by Mice

Notably, some mice consumed the seeds on the spot, while others exhibited ‘dispersal behavior’ by transporting and burying seeds elsewhere, a process known as ‘removal and caching’. This behavior was credited to Hanami Suzuki and Hisashi Kajimura.

Distinct Behaviors and Environmental Impacts Among Mouse Species

The study observed distinct behaviors between the two mouse species. The larger species tended to consume seeds in safer, vegetated areas or transport them from more exposed locations. In contrast, the smaller species often moved seeds regardless of vegetation cover, possibly due to their size influencing vulnerability to other rodents.

Influences of Season and Tree Type on Seed Consumption

Seasonal changes and tree species in the forest also seemed to influence the mice’s immediate consumption of seeds. This behavior was more common in summer and in coniferous forests, likely due to the availability of other food sources, like acorns in broadleaf forests.

The Role of Mice in Seed Dispersal and Forest Health

The researchers emphasized the critical role of field mice in seed distribution and forest regeneration, particularly in broadleaf forests during autumn. Suzuki highlighted the necessity of re-evaluating the relationship between sasa bamboo’s seeding and field mice, considering their influence on forest renewal and vegetation succession.

Challenging Prevalent Theories

Suzuki and Kajimura’s research challenges established theories about seed consumption and storage in field mice. They found that even small seeds, like those of Sasa borealis, are stored by mice, contradicting the belief that only larger seeds like chestnuts and acorns are cached. This discovery suggests a need to revisit existing theories regarding seed dispersal and storage by mice.

Kajimura’s Concluding Remarks

Concluding their findings, Kajimura stated that field mice’s behavior, influenced by their environment, plays a significant role in tree regeneration and the complexity of forest ecosystems.

Reference: Suzuki and Kajimura’s study titled “Utilization of Sasa borealis seeds by Japanese field mouse: discovery of small-seed caching,” published on 10 August 2023 in Frontiers in Ecology and Evolution, offers a novel perspective on the relationship between mice and plant life. DOI: 10.3389/fevo.2023.1124393

Suzuki and Kajimura are affiliated with the Graduate School of Bioagricultural Sciences at Nagoya University, Japan.

Frequently Asked Questions (FAQs) about Field Mice Behavior

More about Field Mice Behavior

• Frontiers in Ecology and Evolution
• Nagoya University Research
• Masting in Sasa Bamboo
• Field Mice Behavior Studies
• Seed Dispersal and Forest Ecosystems
• Dwarf Bamboo Research