Ecological response syndromes in the flora of southwestern Western Australia: Fire resprouters versus reseeders

Two fire-response syndromes can be described for species of the vegetation of Mediterranean-climate, southwestern Western Australia. Resprouters survive fires as individuals. Reseeders are killed by fire and must reestablish through germination and establishment of seedlings. Of the Western Australian plant families analyzed for fire-response strategies, 50% of the Proteaceae, 50% of the Restionaceae, 45% of the Orchidaceae, and 25% of the Epacridaceae are resprouter species. Within genera of the Proteaceae, the proportions of resprouters includeAdenanthos (56%),Hakea (52%),Dryandra (35%), andGrevillea (31%). WithinBanksia, 49% are resprouters, and it appears that the reseeding syndrome is the derived character in this genus. The proportion of resprouters within southwestern Western Australian plant communities ranges from 66% to 80%. These percentages are generally higher than in more arid parts of Western Australia and in comparable plant communities from other Mediterranean-type climates of the world. The relatively high proportion of resprouters within plant families and within plant communities probably indicates that the Western Australian vegetation experiences a harsher fire stress regime than do other Mediterranean-type climate areas. Western Australian plant communities have their highest diversity in the early years after fire, when the vegetation contains a higher number of reseeding species and individuals. Seed banks are dominated by the seeds of reseeders.