Herring Island has local significance for fauna conservation.

The reason for this assessment is:

The Island supports a low fauna species diversity comprising (generally) widespread and common species. The island's habitat types are all in a condition ranging from moderate- poor. In addition to the major physical and rnicro-topographic disturbance caused by the history of silt dumping and mounding, chronic weed invasion has brought about major structural and microhabitat alteration. Some examples of altered riparian habitat consist entirely of introduced native and exotic species. Pest species dominate all fauna groups except the reptile fauna. Bird pests such as Mynas, Starlings and turtle-doves are abundant, foxes are present in high numbers, and introduced rats are present in higher numbers than at any other site surveyed by the author.

In summary, the remnant habitat of the island, and its fauna complement can generally be considered to be highly degraded and are not of high conservation value. Although Herring Island does have potential for rehabilitation with appropriate management, potential future values are not considered in an assessment of current values. Its contribution to wildlife conservation is its role as part of the Yarra corridor.