Closely spaced stable traps were used to determine the preferences of mosquitoes for 6 vertebrates at Kowanyama, northern Queensland, on 4 occasions during the wet and dry seasons of 1974–75. A total of 44 626 mosquitoes from 35 taxa was collected and compared with 26 215 specimens of 15 taxa trapped at Charleville, south-west Queensland, in February 1976. Host preference was analysed in detail for 11 species; Anopheles bancroftii Giles, An. amictus Edw., An. annulipes Wlk., An. farauti Lav., An. meraukensis Venhuis, Aedes bancroftianus Edw., Ae. normanensis (Tayl.), Ae. vittiger (Skuse), Culex annidirostris Skuse, Cx. quinquefasciatus Say (=fatigans Wied.) and Mansonia uniformis (Theo.). All species in these experiments, including the important vector of arboviruses, Cx. annulirostris, preferred mammalian baits, especially calf, although An. bancroftii and Cx. quinquefasciatus preferred man. Blood-meals of 5802 engorged mosquitoes of 21 taxa collected from natural resting sites at Kowanyama village were analysed by the precipitin test. Mammals, particularly dogs, were the most important hosts. Cx. squamosus (Tayl.) and Cx. quinquefasciatus were the only species to feed extensively on birds (75–6 and 28–7%, respectively). Uranotaenia albescens Tayl. fed almost entirely on amphibia. No seasonal shifts in feeding of An. bancroftii, An. annulipes, Cx. annulirostris or Cx. quinquefasciatus were evident from either host-preference or host-feeding patterns, the latter being evaluated using a ‘ Feeding Index ’. These results are discussed in relation to the transmission of arboviruses, particularly Murray Valley encephalitis virus and pulmonary dirofilariasis of man and dogs in Australia.