Environmental Assessment
Volume B-4.2
Mine
Fauna
Ambatovy Project
216
January 2006
Reclamation and Closure
•
Cessation of operations and revegetation with native species will
remove sensory disturbance and reduce edge effects.
Impact Analysis
Sensory Disturbance
Existing noise levels range from 20 to 42 dBA, depending on location and time
of day (Volume B, Section 3.5, Table 3.5-1). Impacts to habitats beyond the
mine footprint from project-generated noise are provided in Table 4.2-5. Primary
noise sources include the engine generator area, scrubber area, haul truck traffic,
process water pumps and the mine face pit (Volume B, Section 3.5). Overall,
azonal, transitional, zonal and ephemeral pond habitats will, proportionately, be
impacted the most by noise generated by mine activities. Azonal and transitional
habitats will be impacted the most (7.6 and 14.2% respectively) by noise levels
above 45 dBA given their proximity to the mine area. Marsh and marsh edge
habitats will only be affected by noise levels above baseline but not exceeding
45 dBA.
Species most likely to be affected by noise include species that use vocalization
for breeding (e.g., amphibians, birds, lemurs) and wary species in areas where
noise exceeds baseline levels, including in the on-site conservation areas. If
noise levels interfere with the ability of individuals to find mates, there could be
potential population effects locally over time. For rare species, these effects
could be regional or beyond regional.
Species most likely to be affected by light include species that are drawn to light
(e.g., moths and insectivorous species such as bats) and those species that are
light sensitive (e.g., Elouard et al. 2003). None of the moth species recorded
during the surveys was identified as rare. Light mitigation will help reduce
impacts and observing the species attracted to the lights will help determine
extent of the impacts and whether additional mitigation is required.
