Refuge or opportunity?  Mosquitoes in some forest remnants: Bushy Park (Wanganui) and  Keebles Bush, Himatangi Bush, Round Bush (Manawatu). 

Mary McIntyre *1

1 University of Otago Wellington

Lowland forest in the Whanganui-Manawatu area is largely reduced to small remnant patches on farmland.   A survey of mosquito species at the Bushy Park Sanctuary, was initially undertaken as part of a ‘BioBlitz’ in Feb & Mar 2016 then repeated in 2017.  Findings are compared with similar surveys using the same methods (overnight CO2-baited light trapping, ovipots) & seasonal time-frame (Feb-Mar) at three Manawatu remnant sites (Keebles Bush, Himatangi Bush, Round Bush) in 2010.   Trapping counts at Bushy Park were low (max/trap.night 7 c.f.  Manawatu sites 210)  in both years, despite mild humid conditions.   Two endemic species were dominant all sites and up to three others present  but there is evidence of decline or benefit from habitat fragmentation according to species.  Two widespread introduced species were also present, typically near the forest edge.  Notable at  all sites  was  occurrence of the Australian species, Aedes notoscriptus around  visitor entry  areas.  Exclusion of pest mammals by a perimeter fence at Bushy Park may also have some influence, since these night active hosts are not available inside the sanctuary.  Furthermore, the fence, as intended, has greatly enhanced forest bird populations of both local and translocated indigenous species.  The presence of both the bird-biting  introduced mosquito vector, Culex quinquefasciatus  & endemic co-vector Culex pervigilans  of the recently introduced avian malaria parasite and  avian pox virus  highlight a need for vigilance.  Apparent absence of the endemic swampland Coquilletidia spp from Bushy Park may relate to relatively recent restoration of the  wetland area from farmland.   A perspective on  fragmentation effects is provided by recent survey data from two large old growth forest sites (Totara Reserve - Manawatu, Wainuiomata Water Catchment - Rimutaka).   

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