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Immediate and longer‐term effects of fire on seed predation by ants in sclerophyllous vegetation in south‐eastern Australia
Author(s) -
ANDERSEN ALAN N.
Publication year - 1988
Publication title -
australian journal of ecology
Language(s) - English
Resource type - Journals
eISSN - 1442-9993
pISSN - 0307-692X
DOI - 10.1111/j.1442-9993.1988.tb00976.x
Subject(s) - sclerophyll , biology , understory , predation , prescribed burn , abundance (ecology) , ecology , eucalyptus , fire regime , seed predation , botany , ecosystem , seed dispersal , canopy , mediterranean climate , biological dispersal , population , demography , sociology
Following a prescribed spring fire at a woodland site with heathy understorey in south‐eastern Australia, the following features changed markedly: the composition of the ant fauna taken in pitfall traps; the abundance of seed‐eating species; seedfall from woody‐fruited Eucalyptus obliqua and Casuarina pusilla ; and rates of seed predation by ants. Broadly adapted species of Monomorium and Rhytidoponera , uncommonly recorded before the fire, became the most abundant ants caught. Seed removal from baits dropped by almost half during the week after fire, despite an increased catch of seed‐eating Rhytidoponera tasmaniensis . This coincided with a massive fire‐induced release of seeds stored inside woody fruits, suggesting that predator satiation occurred. The fall of Casuarina seeds and Eucalyptus chaff returned to pre‐fire (low) levels 1 week after the fire, but a substantial proportion of Eucalyptus seeds fell after several weeks. By this time rates of seed removal were increasing rapidly as the abundance of seed‐eating R. tasmaniensis continued to increase. Weekly removal from baits reached 100% 7 weeks after the fire, which was much higher than any level recorded before it. Results from a nearby heathland site, burned by an earlier fire, indicated that unusually high rates of seed removal, paralleling increases in abundance of R. tasmaniensis , can persist for at least 2 years following fire. These results have potentially important implications for post‐fire recruitment.