attern of Large spiders suggests that the risk associated with relocation increases as spiders become larger and thus more reliant on effective camouflage. Such changes in foraging patterns with age due to changing costs were predicted by Janetos (1982b). This changing relationship between efficient foraging for growth and the need for camouflage can also be seen in the seasonal shift in moves in and out of web sites. For P. noblei a general strategy is to move in spring and summer when rapid growth is occurring, but by autumn many spiders are settling into sites where they will remain until spring (Tables 2a & 2b). Spring is a time of high mobility in all size classes. In fact, 100% of Small spiders end their residence during spring, even though only 60% begin a residence during this period. The 40% discrepancy in numbers will be largely due to the maturation of males. Other size classes also show a high percentage of spiders moving out of established web sites (i.e., ending a period of residency) in spring. This may be to seek a prey-rich web site after a long period of low prey availability over winter. Indeed the model of Leclerc (1991) based on observations of the linyphiid Tenuiphantes flavipes (Blackwall 1854) predicted differential optimal strategies with regard to staying or moving dependent upon the spiders' body fat reserves. So many spring movements could also indicate that staying too long carries risks that balance the dangers of moving. Predators may learn to associate a build up of silk lines with the likely presence of spider prey. For instance, it is often unclear what cue initiates the cryptic prey flushing behavior reported in Sceliphron laetum (F. Smith) (Coville 1987), a technique observed in the capture of Poltys spiders by this wasp (R. Raven pers. comm.).
The long-term figures for Poltys residence times are overestimates to some extent. In particular, many spiders may have been missed because they both arrived and left a web site between samples and this factor would make the long term average residence period more comparable with the figure from the short-term studies. Another factor that accounts for some of the difference between long-term and short-term average residence periods is the omission of spiders that were in aggregations from the former. Nevertheless, many of the studies listed in Table 1 also excluded moves caused by conspecific interactions, so this does not affect the within-table comparison. Finally, the life history of P. noblei, which often extends over more than one season, leads to the inclusion of winter records in the long term averages. Winter is a season of low general mobility and was not sampled in any other study listed in Table 1. Therefore, it can be seen that a realistic figure for the average residence period for P. noblei that is comparable to other studies lies somewhere between the short-term and long-term results reported here. Nevertheless, the long-term results provide information on maximum stays, the distribution of residence times, and some information on differences between spiders of different ages. In fact the single longest recorded stay of P. noblei, of approximately 263 days, seems remarkable for a silk recycling species. Unfortunately this cannot be compared to other species both due to the "snapshot" nature of most studies and due to the differing life-histories. All other species examined are essentially univoltine and this time period would have covered the entire life-cycle from emergence; for this P. noblei, however, this period accounted for approximately two-thirds of its growth, the record covering it from the small end of Medium, through to adult, probably around five instars.
An attraction for web sites with conspecific silk has been demonstrated in at least one orb web species (Schuck-Paim & Alonso 2001) which might indicate the further possibility of overestimation of the period of web site tenacity of Poltys if web site take-overs occurred frequently. This error is most likely to occur among records for smaller specimens that were not 