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Resource supply
Mean breakdown rates used to estimate organic matter supply rates were 2.2 yr -1 (1.3-3
yr -1 ; 95% confidence interval) and 0.6 yr -1 (0.4-0.8 yr -1 ; 95% confidence interval; Table 1) for
leaf-litter and wood, respectively. Using leaf-litter breakdown rates, mean organic matter supply
rates were lowest in Hering (47 g AFDM m -2 yr -1 ) and highest in Tony Sinks (284 g AFDM m -2
yr -1 ; Fig. 2A; Table 5). Using the wood breakdown rates, mean organic matter supply rates were
lowest in Hering (13 g AFDM m -2 yr -1 ) and highest in Tony Sinks (80 g AFDM m -2 yr -1 ; Fig. 2A;
Table 5). Using a P:B ratio of 5, mean macroinvertebrate production was lowest in Hering (0.13
g AFDM m -2 yr -1 ) and highest in Tony Sinks (1.61 g AFDM m -2 yr -1 ; Fig. 2B; Table 5). The large
amount of variability in resource standing stocks translated into wide confidence intervals in the
resource supply rates (Fig. 2A, B).
Trophic basis of production
Mean net production efficiency used to estimate energetic demands for O. australis was
0.46 (0.38-0.54; 95% confidence interval; Table 2). Assuming a diet composed only of organic
matter, demand by O. australis was lowest in Limrock (0.47 g AFDM m -2 yr -1 ) and highest in
Tony Sinks (7.4 g AFDM m -2 yr -1 ; Fig. 2A; Table 5). Crayfish demand was significantly lower
than wood and leaf supply rates in all caves (Fig. 2A,C). Assuming O. australis consumed only
macroinvertebrates, mean demand was lowest in Limrock (0.06 g AFDM m -2 yr -1 ) and highest in
Tony Sinks (0.9 g AFDM m -2 yr -1 ; Fig. 2B, Table 5). Crayfish demand was similar to prey supply
in Hering and Tony Sinks and was significantly lower than prey supply in Limrock (Fig. 2B, D).
The inclusion of zero in the 95% confidence intervals for the macroinvertebrate surpluses in
Hering and Tony Sinks suggests that the demand by O. australis is not significantly different
from supply and does not verify the presence of a resource deficit (Fig. 2D).
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