GUIDELINES / 2.0 Biodiversity
2.7 Stepping Stones and Gaps
Small patches can serve as stepping stones, allowing for species movement between large patches and are important in fragmented landscapes. However, the loss of a stepping stone can often inhibit movement, increasing patch isolation.
At some point, the distance between stepping stones or a gap in a continuous corridor will exceed a threshold at which a particular species will be unwilling or incapable of crossing. These critical gaps should often be restored.
Key Considerations for Managing Gaps
- The greater the contrast between the gap and the corridor plant community, the narrower the gap must be in order not to be a barrier.
- Smaller species will generally have smaller gap thresholds.
- Species requiring specialized habitats will have smaller gap thresholds.
- For visually-orientated species, gap thresholds may be determined by the ability to see the next stepping stone or across the gap.
- In riparian corridors, restore gaps in higher order streams first to provide the greatest benefit for biodiversity.