Data Zone
The site was identified as internationally important for bird conservation in 2004 because it was regularly supporting significant populations of the species listed below, meeting IBA criteria.
Populations meeting IBA criteria ('key species') at the site:| Species | Red List | Season (year/s of estimate) | Size | IBA criteria |
|---|---|---|---|---|
| Slaty-backed Gull Larus schistisagus | LC | breeding (2003) | present | A4i |
Ideally the conservation status of the IBA will have been checked regularly since the site was first identified in 2004. The most recent assessment (2015) is shown below.
| IBA conservation status | |||
|---|---|---|---|
| Year of assessment | State | Pressure | Response |
| 2015 | unfavourable | high | low |
| Whole site assessed? | State assessed by | Accuracy of information | |
| yes | habitat | - | |
| State (condition of the key species' habitats) | |||
|---|---|---|---|
| Habitat | Quantity (% remaining) | Quality (% carrying capacity) | Result |
| Grassland | good (>90%) | poor (40–69%) | unfavourable |
| Pressure (threats to the key species and/or their habitats) | ||||
|---|---|---|---|---|
| Threat | Timing | Scope | Severity | Result |
| Invasive and other problematic species and genes | happening now | most of population/area (50–90%) | moderate deterioration (10–30% in 3 generations) | high |
| Pollution | likely in long term (beyond 4 years) | some of population/area (10–49%) | slow deterioration (1–10% over 3 generations) | medium |
| Response (conservation actions taken for the key species and/or their habitats) | |||
|---|---|---|---|
| Designation | Planning | Action | Result |
| Little/none of site covered (<10%) | No management plan exists, but the management planning process has begun | Some limited conservation initiatives are in place | low |
| Year | Protected Area | Designation (management category) | % coverage of IBA |
|---|---|---|---|
| 1976 | Nemuro hanto | 沿岸水産資源開発区域 (VI) | 11 |
| 2013 | Common fishery right area(Hokkaido) | 共同漁業権区域 (VI) | 22 |
| Habitat | % of IBA | Habitat detail |
|---|---|---|
| Grassland | - | |
| Marine Coastal/Supratidal | - |
Recommended citation
BirdLife International (2025) Important Bird Area factsheet: Tomoshiri and Chitomoshiri islets (Japan). Downloaded from
https://datazone.birdlife.org/site/factsheet/tomoshiri-and-chitomoshiri-islets-iba-japan on 16/01/2025.