Native fish mortality - is it an inevitable consequence of construction works in watercourses?
Not if the fish are first moved out to alternative accommodation, according to Boffa Miskell freshwater ecologist, Eddie Sides.
“Many infrastructure and subdivision projects involve a myriad of development activities that affect waterways, such as installing new or temporary road culverts, constructing stormwater diversion weirs or reinforcing streambeds to protect subsurface tunnelling.
“Given that about two-thirds of native fish species are at-risk or threatened, moving fish out of harm’s way is an easy, lowcost and low-risk way to achieve a great outcome for both the project and the environment,” Eddie recommends. Recently, at Long Bay, where Todd Property Group is developing a new urban community, Boffa Miskell ecologists moved over 250 fish - bullies, inanga (whitebait) and longfin eel - from a 30-metre-long section of stream. The fish, which occurred at a density of over 10 fish per square metre and included two at-risk species, would not have survived the damming, dewatering and excavation of their home habitat when a temporary stream crossing was constructed.
As Eddie explains, “We were able to capture a high proportion of the fish quickly and efficiently and move them a short distance to a suitable release habitat within the same stream.”
3 April 2013