The following is a recent report (-120511) from Christchurch City Council ranger/ornithologist- Andrew Crossland-
Bittern set to be the big winners from the CHCH earthquakes
3 bittern sightings in less than a week in the environs of Brooklands
Lagoon have made me take stock of what a major turn of fortune the CHCH
earthqukes have been for the local conservation of this species.
Elevated river levels (considered to be permanent) have flooded riparian
margins all the way along the Styx River and Kaputone Stream in NE
Christchurch, turning many, many hectares of willow/blackberry infested
riverbank and dry ex-river channels into well-watered riparian wetlands.
The 86 ha Styx Rivermouth wetlands which were essentially tidal
saltmarsh and rivermars prior to the quakes has now expanded by 10+ ha
with large springs flooding a large area of rank grass-covered wasteland
which since the Sept quake has rapidly begun to infill with raupo.
Bittterns have already discovered this habitat, which within 2-4 years
will hopefuly be a vast raupo swamp offering plenty of breeding habitat