The Department of Environment, Food and Agriculture says it hasn't had the resources to achieve a 2025 deadline in the Island's biodiversity strategy.
A Freedom of Information request asked if all the Island's critical biodiversity sites would be protected and managed by 2025 as set out in the Tynwald-backed plan.
But DEFA says with months left to go, it hasn't managed to achieve the goal.
In its response, the department says it hasn't had the resources needed and has also had other priorities.
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