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[Vol. 94 
primarily Solenopsis (t s = 8.79, P < 0.001). Other ant species col- 
lected in pitfall traps were not observed on these prey placed on the 
surface, perhaps due to displacement by fire ants. Flies were more 
successful in utilizing prey in New Hampshire ( t s — 7.23, P< 0.001) 
perhaps also due to displacement by fire ants in Florida. 
At both sites, prey size affected its ultimate utilization. In New 
Hampshire, ants were significantly more successful at utilizing small 
prey (< 30 g, t s = 5.34, P< 0.001) and flies were significantly more 
successful utilizing large prey ( t s = 5.45, P < 0.001). In Florida, 
beetles were less successful in burying small prey (t s — 2.30, P < 
0.02) but ants were equally successful with large or small prey ( t s — 
0.96, P — 0.33; Table 1). 
Discussion 
The wide range of feeding habits of ants produce considerable 
dietary overlap with members of other, unrelated taxa utilizing the 
same resources (see for example Brown and Davidson 1976). 
Because many ant species are opportunistic and scavenge for a wide 
variety of sizes and types of animal prey, it is not unusual that 
carrion may be used as a food source when available. Such a large, 
concentrated resource will induce an extraordinary recruitment 
response from a colony, perhaps exhausting all foragers within the 
nest. Although the sensitive chemoreceptors of Nicrophorus permit 
them to locate carrion over long distances, the high density of forag- 
ers of ant species with well-developed trail communication and 
chemical or aggressive defense of resources may bring burying bee- 
tles and ants into competition for small vertebrate carcasses. Even if 
prey are first found by Nicrophorus, the time during which intra- 
sexual competition occurs and burial is completed could increase 
the time period in which the carcass might be located by ants and 
thus increase the probability that they would displace the beetles. In 
the present study the lack of success of Florida Nicrophorus on 
carcasses was apparently due to interference from fire ants rather 
than to a lack of beetles in the study area because 416 A. carolinus 
were collected from pitfall traps but only five prey (N = 48) were 
buried. The nocturnal activity of some Nicrophorus species might 
favor early detection of carcasses and successful utilization, but this 
advantage would depend upon the temporal pattern of vertebrate 
mortality. Carcasses could also be lost to ants following burial, as 
